December 4, 2009
Ida's Effects Still Visible in Coastal Maryland and on Mid-Atlantic Beaches
Hurricane Season 2009: Hurricane Ida (Atlantic Ocean)
Residents in coastal areas from North Carolina all the way up to New England were hit hard from "Ida the Coastal Low" when it dumped extreme amounts of rainfall on its track up the eastern seaboard of the U.S. during the first and second weeks in November. Some of those effects are still visible, like the beach erosion it left behind.
In Maryland's Calvert County, the Neelds Estate neighborhood lost a lot of beach area and even now, almost a month after the storm, there are sandbags still helping to protect homes.
Karl Hille, who works at NASA Goddard Space Flight Center in Greenbelt, Md. has relatives who live there. Karl said, "The beach cottages of the Neelds Estate neighborhood were some of the worst hit in Calvert County by Hurricane Ida’s storm surge. Water swirling off of the Breezy Point jetty gouged away up to 50 feet of beach, digging down two feet and leaving some homes’ foundations exposed. A half mile down-stream, the storm deposited much of the sand, doubling the beach area there."
Flooding was reported in several areas of Calvert County during the storm, including the areas of Broomes Island, Neeld Estates, Long Beach and Cove Point. During November 12 and 13, as many as 3,300 residents were without power. The county also reported that as a result of the extreme rainfall, about 230,000 gallons of untreated wastewater poured into the Patuxent River.
Rainfall and power outages were much more extreme in coastal Virginia, the rainfall totals were the highest. Here are some towns and their rainfall in inches: Chesapeake – 11.92; Hampton – 11.86; Suffolk – 10.58; Langley Air Force Base – 10.58; Oceana – 10.29; Newport News – 9.76; Portsmouth – 8.66; Norfolk – 8.47.
In Norfolk, the high tide came in with gusty northeasterly winds and created a 7.74 foot storm surge there on Thursday, November 12. That surge almost matched Hurricane Isabel's surge of 7.9 feet in 2003.
Damages were so severe in eastern Virginia that the U.S. Small Business Administration sent representatives to the cities of Norfolk and Hampton at the end of November to help people with federal loan assistance who suffered property damage. Homeowners were eligible for loans up to $200,000 to repair or replace damaged real estate.
It hasn't yet been one month since "Ida the coastal low" battered the Mid-Atlantic coast, but people will remember it for a long time to come.
Rob Gutro, NASA/Goddard Space Flight Center
November 18, 2009
Ida's Damages in Virginia Being Assessed, NASA Wallops Walloped with Rain
Residents in eastern Virginia and northeastern North Carolina were hit especially hard by the heavy rains from last week's coastal low pressure area, formerly known as hurricane Ida. Employees at NASA's Wallops Island facility in Wallops Island, Virginia had a first-hand experience with "Ida the coastal low."
Rebecca Powell, a Public Affairs Officer at NASA Wallops said, "As a coastal area, Wallops Flight Facility takes all storms seriously. We were able to prepare for the storm ahead of time, which was very helpful. Throughout the event, we had 5.43 inches of rain and a high wind gust of 59 mph. Our tides ran approximately 3-4 feet higher than a normal high tide, so we did have some minor flooding. Compared to other local areas, though, we fared well."
The Federal Emergency Management Agency's damage assessment teams were touring Hampton Roads, Virginia this week and documenting damages. The assessment will help determine if the state of Virginia is eligible for federal disaster assistance.
During the storm as many as 270,000 people lost power in the eastern Virginia region. One visible sign remaining from Coastal Low Ida is a beached barge in the Sandbridge area of Virginia Beach, which suffered the most damages from the storm.
In coastal Virginia, the rainfall totals were the highest. Here are some towns and their rainfall in inches: Chesapeake – 11.92; Hampton – 11.86; Suffolk – 10.58; Langley Air Force Base – 10.58; Oceana – 10.29; Newport News – 9.76; Portsmouth – 8.66; Norfolk – 8.47.
On November 16, the Virginia Pilot on-line reported that cities are still assessing damage costs from the coastal low. The city of Norfolk estimated that more than $25 million of damage was done, most of it from flooding. The city of Portsmouth placed damages over $450,000 and authorities in Virginia Beach estimated about $3.4 million worth of damage to private property. The beach itself was hit hard with an estimate of about $10 million of sand erosion.
The National Park Service reported that the Virginia side of Assateague Island was closed due to parking lots covered in sand, downed trees and many tires that washed up on the beaches. The tires were part of an artificial reef on the ocean's bottom. The coastal low dumped a lot of rain and a strong storm surge that went over portions of the barrier island, but the famous wild ponies had found high ground and were reported safe. The Assateague Island visitor center for the wildlife refuge will likely re-open today, Wednesday, November 18.
In Hampton Roads, Virginia, the U.S. Army Corps of Engineers has to start all over again with replenishing Cape Henry beaches. The coastal low eroded most of the sand and swept it back into the ocean.
After receiving almost a foot of water in various areas, clean up efforts will continue for some time to come. "The basement of my home did experience some flooding," Powell said. "Although frustrating, I know it can be cleaned up and repaired, however others weren't as lucky, so I won't complain."
Rob Gutro, NASA/Goddard Space Flight Center
November 16, 2009
NASA's MISR Instrument Gets Cross-Track Winds for Hurricane Ida
On Sunday, Nov. 8, 2009 at 16:34 UTC (10:34 a.m. CST) the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA’s Terra satellite passed over Hurricane Ida while it was situated between western Cuba and the Yucatan Peninsula. MISR captured the height and cross-track (east-west) motion of Ida's clouds.
According to the National Hurricane Center, at 15:00 UTC, the hurricane had an estimated minimum central pressure of 983 millibars, with maximum sustained winds of 148 kilometers per hour/41 meters per second (92 miles per hour – corresponding to a Category 1 storm on the Saffir-Simpson scale. Three hours later, at 18:00 UTC, the minimum central pressure had decreased to 978 millibars, and the maximum sustained winds increased to 157 kilometers per hour/44 meters per second (98 miles per hour) – corresponding to a Category 2 storm.
At 21:00 UTC, the storm reached it maximum intensity, with a minimum central pressure of 976 millibars, with sustained winds near 167 kilometers per hour/46 meters per second (104 miles per hour). Ida eventually made landfall in the United States as a tropical storm with maximum sustained winds of 72 kilometers per hour/20 meters per second (45 miles per hour) at Dauphin Island, Ala., on Tuesday, November 10.
The first pair of images MISR captured included a visible image from MISR’s nadir viewing camera, and a prototype retrieval of high-resolution (1.1 kilometers, or 0.7 miles) cross-track cloud motion heights and winds superimposed on the second image. The eye of Hurricane Ida is on the far right of the images and black regions in the images indicate the extent of the MISR 380-kilometer-wide (236-mile-wide) image swath. The low clouds in the second image showed the characteristic counterclockwise flow (from east to west for clouds north of the hurricane eye and the opposite to the south of the eye) associated with strong low pressure in the Northern Hemisphere.
MISR uses a stereophotogrammetric technique to simultaneously retrieve the height and cross-track (east-west) motion of clouds. This technique relies on MISR's nine cameras that provide 275-meter (902-foot) resolution views of a single scene from different angles over a period of approximately seven minutes. An automatic pattern matching algorithm finds cloud top features that are common among the MISR camera images and determines the displacement of these features over time. Because the retrieval is purely geometric, the height assignment is very robust.
For Hurricane Ida, the highest clouds are found at an altitude above 15 kilometers (9.3 miles) – higher than a typical passenger aircraft flies. The prototype cross-track wind retrieval uses the time difference between different camera views to infer the motion of features orthogonal to the (north to south) motion of the satellite. The retrieval of both height and wind is done at a spatial resolution of 1.1 kilometers (0.7 miles). Observations of this type are extremely difficult to acquire from ground-based or airborne platforms.
The second set of MISR images showed the detail of the clouds near the hurricane eye. At the time of the satellite overpass, Ida’s eye was "closed," meaning that it was covered by clouds, so the typical dark eye caused by descending air in the center of the hurricane vortex is not visible. In this case, however, strong thunderstorms nearly reaching the stratosphere were visible as "bubbles." Upon reaching the stratosphere, the tops of thunderstorms rapidly spread out. The clouds to the west of the strongest storms are moving toward the west, while the clouds to the east are moving east. The speed this motion retrieved by MISR ranges from 10 to 30 meters per second (36 to 108 kilometers, or 22 to 67 miles, per hour).
The bubbling cloud tops observed by MISR are a relatively common feature of intensifying tropical storms, such as Hurricane Ida. They are associated with what are known as "vortical hot towers," which have been observed by other NASA satellite instruments, such as the Tropical Rainfall Measuring Mission (TRMM) that carries a precipitation radar that can look below the hurricane cloud tops.
By rapidly bringing energy from the ocean surface up through the atmosphere, hot towers play an important, but not completely understood, role in storm intensification. The animation shows the development and spreading out of the clouds at the top of the hurricane over the seven-minute time period of the MISR instrument overpass. The spatial resolution of the images is 275 meters (902 feet) and the images are registered to the top of the hurricane to highlight the rapid development of the cloud features associated with the hot towers.
Michael J. Garay/Raytheon Corporation and Alan Buis/NASA Jet Propulsion Laboratory
NASA's TRMM Satellite Mapped "Ida the Low's" Rainfall From Space
The Tropical Rainfall Measuring Mission satellite known as "TRMM" has the ability to measure rainfall from space, and assessed the heavy rainfall from last week's coastal low pressure area, formerly known as "Ida" that drenched the U.S. east coast.
Tropical storm Ida came ashore early on November 10, 2009, quickly weakened to a tropical depression and then became extratropical. A strong pressure gradient then developed between the remnants of Ida (a "coastal low pressure area") and an area of high pressure that had moved over New England. This resulted in strong winds blowing toward east coast shorelines that resulted in coastal flooding. Flooding tides in Virginia were near the values set by hurricane Isabel in 2003. The remnants of Ida also dropped heavy rainfall from the Gulf Coast to New Jersey resulting in flash floods.
Hal Pierce a meteorologist who works on the TRMM science team at NASA's Goddard Space Flight Center in Greenbelt, Md. created a rainfall analysis that merged rainfall Data (3B42) from TRMM, other NASA satellites, U.S. Department of Defense satellites, National Oceanic and Atmospheric Administration polar-orbit satellites, and geostationary satellites. The analysis shows Ida's remnants resulted in large areas of very heavy rainfall with maximums in Alabama, North Carolina and Virginia. The analysis shows a maximum value over land of over 240 mm (~9.4 inches).
Heavy rain amounts (from satellites) and flood potential calculations (from a hydrological model) are updated every three hours globally with the results shown on the "Global Flood and Landslide Monitoring" TRMM web site pages.
To see an animation of calculated flood potential as Ida moved from Nicaragua to the the United States, go to: http://trmm.gsfc.nasa.gov/trmm_rain/Events/ida_flood_potential_6-13nov09.mpg
TRMM is a joint mission between NASA and the Japanese space agency JAXA.
Hal Pierce, SSAI/ NASA Goddard Space Flight Center
November 13, 2009
Satellite Imagery Confirms Ida's Low is Finally Moving Away from the East Coast
Satellite imagery and weather ground station readings today along the Mid-Atlantic indicate "Ida the coastal low pressure area" is finally moving away from the U.S. east coast.
The Geostationary Operational Environmental Satellite, GOES-12 captured a visible image of "Ida the Coastal Low" this morning, Friday, November 13 at 10:31 a.m. ET. The image revealed the low pressure system as large area of clouds stretching from the Canadian Maritimes down to South Carolina. GOES is operated by the National Oceanic and Atmospheric Administration, and NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. creates some of the GOES satellite images.
NASA's Aqua satellite captured an infrared image that more clearly showed the higher clouds and heavier rains moving away. The Atmospheric Infrared Sounder (AIRS) instrument that flies on the Aqua satellite captured the coastal low's western edge of high clouds over the easternmost part of the U.S. east coast at 2:17 a.m. ET today.
At 10 a.m. ET, the National Oceanic and Atmospheric Administration's Hydrometeorological Prediction Center in Camp Springs, Md. reported that the center of Ida's remnants were now 90 miles south-southeast of Hatteras, North Carolina and 110 miles east-southeast of Morehead City, North Carolina. That puts the center near 34.0 North latitude and 74.7 west longitude.
The coastal low has moved in a southeasterly direction from its location yesterday, November 12, and will continue to track southeastward, away from the Carolina coast. The low's circulation has continued to gain strength at sea and now has maximum sustained winds near 65 mph. The low's minimum central pressure is 995 millibars.
Although the low is pulling away, and its rains are easing along the Mid-Atlantic U.S. coast today, it is leaving behind a great deal of flooding, particularly in eastern Virginia and northeast North Carolina. Flood warnings and advisories remain in effect for portions of the central Gulf coast, the southeastern U.S. and the Mid-Atlantic States. High wind, gale and storm warnings are also in effect along coastal regions of the Mid-Atlantic States.
Eastern Virginia and northeastern North Carolina reported extreme rainfall amounts as of 7 a.m. ET today, November 13. The following are towns in North Carolina and their rainfall in inches: Swansboro – 9.51; Sneads Ferry – 8.76; Newport – 8.45; James City; 7.77; Surf City – 7.55.
In coastal Virginia, the rainfall totals were the highest. Here are some towns and their rainfall in inches: Chesapeake – 11.92; Hampton – 11.86; Suffolk – 10.58; Langley Air Force Base – 10.58; Oceana – 10.29; Newport News – 9.76; Portsmouth – 8.66; Norfolk – 8.47
Rainfall was much less the farther inland. The Nation's Capital reported 1.54 inches of rainfall at Reagan International Airport.
Additional rainfall amounts of an inch or less are expected across the coast of the northern Mid-Atlantic States and southern New England.
Rob Gutro, NASA/Goddard Space Flight Center
November 12, 2009
Former Ida a Huge Rainmaker, Causing Flooding in the Mid-Atlantic
The coastal low, formerly known as Ida, is currently quasi-stationary off the North Carolina coast, adding more rain on top of what it has already brought. The low is creating serious flooding from northeast North Carolina to coastal Virginia.
A retired employee of NASA's Wallops Flight Facility provided photographs of flooded roadways in Accomack County, Virginia, and reported trees down and other damages this afternoon.
What's interesting is that Ida is a stronger system now as a coastal low pressure system than when it made landfall in Dauphin Island, Alabama as a tropical storm. At that time, its minimum central pressure was 999 millibars. Today, its minimum central pressure is 992 millibars.
At 4 p.m. ET the center of remnants of Ida was located near latitude 35.2 north and longitude 75.8 west, that's 15 miles west of Hatteras, North Carolina and 65 miles south-southeast of Elizabeth City, North Carolina. The low has maximum sustained winds near 45 mph with higher gusts. Some of those higher gusts have been reported in Hampton, Virginia, and in Accomack County, Virgina.
The low is expected to sit where it is off the North Carolina coast through early Friday before slowly moving eastward. The Geostationary Operational Environmental Satellite GOES-12 noticed that the former Ida hasn’t moved much since this morning.
GOES-12 is operated by the National Oceanic and Atmospheric Administration. NASA's GOES Project that creates GOES imagery is located at NASA's Goddard Space Flight Center, Greenbelt, Md.
NOAA's Hydrometeorological Prediction Center said this afternoon that "additional heavy rains of 2 to 4 inches are expected through eastern Virginia...eastern and southern Maryland...Delaware...and New Jersey through Friday morning. Isolated totals around 6 inches are possible."
Rob Gutro, NASA/Goddard Space Flight Center
|WARRIOR LOCK AND DAM|| 6.15|
|SMITHS 5NW|| 5.55|
|DEMOPOLIS LOCK & DAM||5.46|
|GEORGETOWN/SUSSEX CO. ARPT||1.70|
|PENSACOLA RGNL ARPT||4.08|
|DE FUNIAK SPRINGS 12WNW||4.02|
|COLUMBUS 15NW (GA POWER CO)||7.25|
|ATLANTA 4N-PEACHTREE CREEK||5.72|
|MONTICELLO (WATER PLANT)||5.70|
|MORGAN FALLS DAM||5.65|
|COLUMBUS METRO ARPT||5.60|
|FORT BENNING (COLUMBUS)||5.34|
|ATLANTA TENNIS COURT||5.20|
|PEACHTREE CITY/ATLANTA WFO||5.03|
|PATUXENT RIVER NAS||2.85|
|ST INIGOES/WEBSTER FIELD||2.50|
|OCEAN CITY MUNI ARPT||1.68|
|OXON HILL 1SE||1.46|
|ANDREWS AFB/CAMP SPRINGS||1.45|
|SALISBURY RGNL ARPT||1.22|
|ANNAPOLIS - US NAVAL ACADEMY||1.13|
|NEW AUGUSTA 1N||3.28|
|SWANSBORO 3.3 NW||9.26|
|NATL WEATHER SVC NEWPORT||8.15|
|NEW RIVER MCAS||6.44|
|NEW BERN/CRAVEN CO. ARPT||6.13|
|GREENVILLE - TAR RIVER||6.00 |
|ELIZABETHTOWN (LOCK 2)||5.87 |
|FAYETTEVILLE 11WNW||5.39 |
|HENDERSONVILLE 6SW (IFLOWS)||5.31|
|CONCORD 6SW||5.30 |
|CLAYTON 3W||5.20 |
|ESTELL MANOR||1.13 |
|CLARKS HILL 2W||6.18|
|TABLE ROCK DAM||5.03|
|GALIVANTS FERRY||5.01 |
|MULLINS 4W||4.90 |
|NORTH MYRTLE BEACH||4.89 |
|ANTREVILLE 2N||4.78 |
|ST MATTHEWS 12NW||4.70 |
|ALLENDALE 2NW||4.70 |
|LITTLE MOUNTAIN||4.68 |
|AIKEN 18SE||4.67 |
|WEST PELZER||4.58 |
|CALHOUN FALLS||4.55 |
|GREENVILLE/SPARTANBURG AP||4.52 |
|WALHALLA 5NW||4.43 |
|CHAPPELLS 2NNW||4.42 |
|SALUDA FILTER PLANT||4.36 |
|CHAPPELLS 2W||4.36 |
|JOHNSTON 4SW||4.25 |
|TRAVELERS REST 1S||4.21 |
|S. RABON CREEK||4.19 |
|CHESNEE 7WSW||4.17 |
|JOCASSEE 2ESE||4.15 |
|GREENVILLE DOWNTOWN ARPT||4.14 |
|CLEARWATER 2SSW||4.10 |
|CLEMSON/OCONEE CO. RGNL ARPT||4.05 |
|MOUNT LECONTE||4.11 |
|NEWPORT - FRENCH BROAD RVR (TVA)||3.62 |
|COPPERHILL (TVA)||3.62 |
|SEVIERVILLE/LITTLE PIGEON RIVER||3.35 |
|GATLINBURG 2SW/PARK HQ (IFLOWS)||3.34 |
|DOUGLAS DAM (TVA)||3.31 |
|GATLINBURG (TVA)||3.17 |
|TELLICO PLAINS (TVA)||3.10 |
|WILDWOOD (TVA)||3.06 |
|OAK GROVE (TVA)||3.02 |
|JONES CREEK IFLOWS||9.12 |
|POOR MTN. IFLOWS||8.88 |
|MARROWBONE RES. IFLOW||8.08 |
|SLOAN BRANCH IFLOWS||6.80 |
|FERRUM IFLOWS||6.80 |
|EDEN COOP||6.17 |
|COPPER HILL IFLOWS||6.04 |
|NICHOLLS KNOB (IFLOWS)||5.84 |
|WAYNESBORO 13SSW||5.32 |
|BACK BAY 1NE||5.10 |
|NEWPORT NEWS/WILLIAMSBURG INL AP||4.93 |
|GLADE CK (IFLOWS)||4.76 |
|ROANOKE MUNI ARPT||4.71 |
|HUDDLESTON 4SW||4.71 |
|STUART 1SSE||4.60 |
|TROUTVILLE (IFLOWS)||4.56 |
|LYNCHBURG RGNL ARPT||4.56 |
|BLACK ROCK MTN (IFLOWS)||4.56 |
|SUFFOLK 8S||4.49 |
|BLACKSBURG 11E||4.49 |
|LANGLEY AFB/HAMPTON||4.44 |
|PHILPOTT 2W||4.35 |
|LITHIA (IFLOWS)||4.28 |
|NORFOLK NAS||4.27 |
|WAYNESBORO 12SSW||4.16 |
|OCEANA NAS/SOUCEK||4.15 |
|TINKER CREEK (IFLOWS)||4.12 |
|ROCKY MOUNT||4.10 |
|DALEVILLE (IFLOWS)||4.08 |
|NORTH FORK (IFLOWS)||4.04 |
|WHITE SULPHUR SPRINGS||2.66 |
|UNION 3SSE||2.54 |
Ida Now a Coastal Low Assaulting the Mid-Atlantic
Ida is one stubborn girl. Her remnants have moved out to sea and reformed as a powerful coastal low pressure system that's been raining on the mid-Atlantic since Tuesday night, November 10. The Geostationary Operational Environmental Satellite, GOES-12 captures images of the low's cloud cover several times every hour, and shows its cloud cover stretching from North Carolina up to Maine. Rains are currently confined to the Mid-Atlantic from North Carolina to New Jersey, but will creep north with the progression of the low.
Forecasts indicate that she'll continue to rain on the Mid-Atlantic until late Friday and bringing high water, gusty winds, coastal erosion, tidal flooding along coastal areas, and inland flooding.
The GOES-12 satellite will continue to track the low's progress and provide satellite imagery for forecasters to pinpoint its position as it moves north. GOES is operated by the National Oceanic and Atmospheric Administration, and NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. creates some of the GOES satellite images.
Northeastern North Carolina, coastal Virginia, southern coastal Maryland, and Delaware will receive the brunt of the low pressure system today and tomorrow. The low's center is going to move over northeastern North Carolina today on its slow creep north.
Nags Head, North Carolina will face rain, heavy at times and possibly a thunderstorm. The winds won't be tropical storm force, but they'll be sustained from the northeast between 25 and 30 mph. Like the rest of northeast North Carolina, they're facing a High Wind Warning; Coastal Flood Warning and a Flood Advisory.
The Atmospheric Infrared Sounder (AIRS) instrument that flies onboard NASA's Aqua satellite captured an infrared image of the low's cloud top temperatures. The colder the temperature, the higher the thunderstorms, and the stronger they are (with heavier rainfall). Infrared imagery on November 11 at 1:30 p.m. ET noticed that the low didn't have thunderstorms near the top of the troposphere (which would indicate the strongest storms having cloud tops colder that -63 Fahrenheit). Instead, the low did have cloud tops that were about 240 Kelvin, or minus 27F, indicating thunderstorms that are not as powerful as you'd see in a powerful hurricane, but still with the ability to produce a good amount of rainfall.
Significant flooding has been reported in Norfolk, Virginia this morning. Many roads were reported closed during the early morning hours today, November 12. The Chesapeake Bay Tunnel was reported open at 7:42 a.m. ET today, but could close because of the rain.
NASA's Wallops Island facility in Wallops Island, Virginia, Norfolk, Virginia Beach and all of coastal Virginia areas are facing tropical-storm like conditions today. The National Weather Service has posted a High Wind Warning, Coastal Flood Warning, High Surf Advisory and a Flood Watch. The forecast in those areas today calls for rain, heavy at times. Just like a tropical storm, the coastal low pressure area is kicking up strong winds. Northeast winds along those coastal Virginia areas will be blowing between 33 and 37 mph, with gusts as high as 55 mph.
Even as far inland and Baltimore and Washington, DC, a Flood Watch is in effect for today and Friday, and 1-2" of rain are expected today, with an additional 1-2" of rain overnight and another 1-2" of rain on Friday! So, the Nation's Capital could see up to 6 more inches of rain by Friday evening. Gusty winds between 25-35 mph are also expected.
Between 6-12" of rain are expected in areas from northeast North Carolina to eastern Virginia and southern Maryland and Delaware over the next two days, so residents in those areas could see significant flooding along the coasts and inland.
To see National Weather Service live radar along the Mid-Atlantic and U.S. Northeast, go to: http://radar.weather.gov/Conus/northeast_lite_loop.php
Tomorrow New Jersey and Long Island, New York will receive the brunt of the low and those residents should be clearing their street drains of fallen leaves now, to prevent additional ponding of water and street flooding.
Rob Gutro, NASA/Goddard Space Flight Center
November 10, 2009
GOES Satellite Movie Captures Extra-tropical Storm Ida Raining on U.S. Southeast
Ida is now an extra-tropical storm over the western Florida Panhandle and is moving east.
In GOES-12 satellite imagery from this afternoon, Ida appeared to be at the southern end of a cold front that stretches from the U.S. southeast to New England.
This afternoon, most of Ida's rains extend to the north and east of her center, over Alabama, Georgia, South and North Carolina.
The Geostationary Operational Environmental Satellite, GOES-12 has been providing meteorologists with satellite imagery of Ida's progression, and the NASA GOES Project created an animation showing Ida's progress.
The GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. uses the data from the National Oceanic and Atmospheric Administration's Geostationary Operational Environmental (GOES) satellites to create images and movies. In this case, GOES-12 provided the data to make a movie of Ida's movements from November 8 to 10 at 19:45 UTC (2:45 p.m. ET).
At 2:30 p.m. ET today, November 10, the low pressure center of Extra-tropical Storm Ida is currently over the western tip of the Florida panhandle and is beginning to move east. The Hydrometeorological Prediction Center issued a graphic indicating extreme rainfall on their website that indicates the area where North Carolina and South Carolina meet the northeast corner of Georgia and extreme southeast corner of Tennessee.
At 10 a.m., Ida's center was near 30.6 North and 87.6 West or 30 miles east-southeast of Mobile, Alabama and 25 miles west-northwest of Pensacola, Florida. At that time, Ida had sustained winds near 35 mph, and the storm was weakening. Ida was moving northeast near 9 mph and had a minimum central pressure near 1000 millibars.
At 10 a.m. ET, Ida became extra-tropical. A conversion to "extra-tropical" status means that the area of low pressure, in this case Ida, eventually loses its warm core and becomes a cold-core system. During the time it is becoming extra-tropical the cyclone's primary energy source changes from the release of latent heat from condensation (from thunderstorms near the storm's center) to baroclinic (temperature and air pressure) processes. When a cyclone becomes extra-tropical it will usually connect with nearby fronts and or troughs (extended areas of low pressure) consistent with a baroclinic (pressure) system. When that happens it appears the system grows larger while the core weakens.
The National Hurricane Center (NHC) used satellite and surface observations to confirm Ida's transition to extra-tropical status. This morning's NHC discussion noted "the latest satellite imagery shows a comma-like appearance and temperature data from Dauphin Island showed a 5F temperature decrease after the center passed this morning."
Ida is expected to produce total rain accumulations of 3 to 6 inches...with isolated maximum storm totals of 8 inches...through Wednesday evening from the eastern Gulf coast across the southeastern U.S. into the southern mid-Atlantic states.
Rob Gutro, NASA/Goddard Space Flight Center
New NASA 3-D Video Shows Thunderstorms in Tropical Storm Ida
NASA's Tropical Rainfall Measuring Mission, or TRMM satellite has the ability to provide data that can be made into three-dimensional images. Visualizers at NASA's Goddard Space Flight Center in Greenbelt, Md. used TRMM data to create a 3-D movie to better see the thunderstorms in Ida.
NASA's TRMM spacecraft observed Tropical Storm Ida on November 9, 2009 at 1218 UTC (7:18 a.m. ET) just before Ida made landfall. Ida made landfall at 6:40 a.m. ET on November 10.
In the animation, scattered convective thunderstorms are shown producing moderate to heavy rainfall of over 50 millimeters per hour (~2 inches) north of Ida's center of circulation and in a strong band on the eastern side. At the time, Ida had winds estimated at 70 knots (~80.5 mph). The rain structure in the animation was taken by TRMM's Tropical Microwave Imager (TMI) and TRMM's Precipitation Radar (PR) instruments. TRMM looks underneath of the storm's clouds to reveal the underlying rain structure. The colored isosurface under the clouds show the rain seen by the PR instrument.
In the animation, light rain (0.25 inches) is depicted in blue, heavier rain (25 mm or 1 inch per hour) in yellow and extremely heavy rain in red (50 mm or 2 inches per hour).
TRMM is a joint mission between NASA and the Japanese Space Agency, JAXA. For more information, visit NASA's TRMM Web site: http://trmm.gsfc.nasa.gov/
Lori Perkins and Rob Gutro, NASA/Goddard Space Flight Center
GOES Satellite Sees Bulk of Ida's Clouds and Rain Inland While Center Making Landfall
Tropical Storm Ida made landfall around 6:40 a.m. ET this morning on Dauphin Island, along the Alabama coastline. NASA's GOES Project created the latest image from Geostationary Operational Environmental Satellite (GOES-12) data showed that the bulk of Ida's clouds and rain are now inland, even though Ida's center was just near the Alabama coast.
Ida has the potential to produce rainfall measuring 3 to 6 inches an hour from areas that include the western panhandle of Florida, north and central Georgia, eastern Tennessee, South Carolina and North Carolina. Some isolated areas may even receive as much as 8 inches of rainfall. The largest swaths of rain expected today will stretch from east of Panama City to Tallahassee, Florida and Birmingham, Alabama east to Atlanta, Georgia.
This morning, November 10 at 7 a.m. ET, Ida was still a tropical storm with maximum sustained winds near 45 mph. Tropical storm force winds extend outward up to 175 miles from the center.
The Geostationary Operational Environmental Satellite, GOES-12 captured a visible image of Ida's landfall on November 10 in Alabama. GOES is operated by the National Oceanic and Atmospheric Administration, and NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. creates some of the GOES satellite images.
Ida is expected to continue weakening and will transition into an extra-tropical storm later today. Ida's center was about 25 miles south of Mobile, Alabama, near 30.3 North latitude and 88.0 West longitude. Ida is moving northeast near 9 mph and will continue in that direction before turning eastward. The estimated minimum central pressure is 999 millibars.
Last night, sixteen-foot waves were reported from an oil rig located 20 miles off the coast of Pensacola, Florida. Ida forced cruise ships heading out of Florida and Texas to change course yesterday, too. Last night, winds were gusting to 50 mph at Pass Christian, Mississippi. Pascagoula, Mississippi reported flooding and tree damage.
At 7:40 a.m. ET today, Orange Beach, Alabama was no longer getting rainfall, but was experiencing gusty winds, and a hint of sunshine was reported through the cloud cover. The National Weather Service has issued a flash flood watch for the north and central areas of Georgia as Ida's remnants move through the southeastern U.S.
To see the rainfall in motion throughout the southeast, visit the National Weather Service Web site: http://radar.weather.gov/Conus/southeast_lite_loop.php
Tomorrow and Thursday Ida's energy will merge with an approaching cold front from the west and will bring heavy rainfall on the eastern part of the Carolinas as the remnants move north-northeast and out into the Atlantic Ocean. Once in the Atlantic, Ida's remnants are expected to run north along the coast as a Low pressure system bringing rains to the mid-Atlantic states.
Rob Gutro, NASA's Goddard Space Flight Center
November 09, 2009
NASA Satellites See Ida Spreading Out Before Landfall
NASA's Aqua and Terra satellites are keeping a close eye on Tropical Storm Ida, and both have instruments aboard that show her clouds and rains are already widespread inland over the U.S. Gulf coast states. Infrared NASA satellite imagery revealed that Ida lost the "signature shape" of a tropical cyclone, and that the storm's clouds have already spread far to the north (over land) of its center of circulation.
At 4 p.m. EDT on November 9, Tropical Storm Ida's maximum sustained winds were near 70 mph. Tropical storm force winds extend outward up to 200 miles from the center. Ida was located near 28.4 North and 88.5 West. That's about 60 miles south-southeast of the mouth of the Mississippi River and about 165 miles south-southwest of Pensacola, Florida. Ida is moving north near 18 mph, and is expected to turn to the east after landfall. Minimum central pressure is 991 millibars. Tropical storm force winds extend outward up to 200 miles from the center.
The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite captured cold thunderstorm cloud tops of Ida in an infrared image at 1:47 p.m. EDT on November 9. The image showed Ida's clouds and rains have spread over Louisiana, Mississippi, Alabama, Tennessee, Georgia and Florida as its center approaches the coast.
The infrared imagery revealed that the cloud tops are not as cold as they were (colder than -63 Fahrenheit) when Ida was a hurricane, indicating Ida has weakened.
In addition to satellite imagery showing that Ida's center is shifting, the National Hurricane Center's last hurricane hunter aircraft fix showed the 700 millibar and surface centers of Ida coming apart, or "decoupling." If you think of a tropical storm link the children's spring toy, "Slinky," the top part of the spring would be leaning over the bottom.
The Moderate Imaging Spectroradiometer instrument on NASA's Terra satellite also provided a visible image of Tropical Storm Ida's cloud cover as she was approaching the U.S. Gulf coast at 12:15 p.m. ET today, and showed the cloud cover spreading out.
Tropical storm warnings are still in effect from Grand Isle, Lousiana to Aucilla River, Florida, including New Orleans and Lake Pontchartrain. Rainfall is still expected between 3 to 6 inches, with up to 8 inches in areas from the Gulf Coast northward into the eastern Tennessee Valley and the southern Appalachians.
Live radar from the National Weather Service from Mobile, Alabama: http://radar.weather.gov/radar.php?rid=MOB&product=NCR&overlay=11101111&loop=yes
; Fort Rucker, Alabama radar: http://radar.weather.gov/radar.php?product=NCR&rid=eox&loop=yes
; and northwest Florida radar: http://radar.weather.gov/radar.php?product=NCR&rid=evx&loop=yes
Ida's center of circulation is expected to make its official landfall during the early morning hours on Tuesday, November 10, and large and dangerous surf and a storm surge of 3 to 5 feet are forecast to accompany Ida's center.
Rob Gutro, NASA's Goddard Space Flight Center
NASA Satellites Make a Movie and Get Rainfall, Wind Info on Ida
NASA satellites are amazing examples of technology. The TRMM satellite peers into tropical cyclones and can tell how much rain is falling per hour and where. QuikScat uses microwave technology to measure Ida's surface wind speed. The GOES-12 satellite, operated by NOAA, produces stunning visuals that are now made into movies by NASA. Both of these satellites have provided the latest views of Tropical Storm Ida today.
Since this morning Ida weakened to tropical storm strength as a result of wind shear (winds blowing at different levels of that atmosphere that can tear a storm apart) and cooler waters. Tropical cyclones need sea surface temperatures of 80 degrees Fahrenheit or warmer to maintain strength.
NASA satellites have helped forecasters see that much of the rainfall and cloud cover are north of the storm's center.
The Tropical Rainfall Measuring Mission (TRMM) satellite flew over Ida earlier today November 9, at 1217 UTC (7:17 AM EST) just before she dropped down from hurricane status. TRMM data showed Scattered convective thunderstorms are shown producing moderate to heavy rainfall of over 50 millimeters per hour (~2 inches) north of the storm and in a strong band on the eastern side. At that time Ida had winds estimated at 70 knots (~80.5 mph), they've since dropped.
This morning's TRMM overpass showed that most of the deep convection (rising air and developing thunderstorms) has been sheared off by wind shear, and pushed northeast of the center of circulation. TRMM showed only a small area of convection around the center.
At 1 p.m. ET, Tropical Storm Ida still had maximum sustained winds near 70 mph, and it was moving north-northwest near 18 mph. Ida is going to turn north, then north-northeast over the next 24 hours. That means, that Ida's center is expected to make landfall along the northern Gulf coast Tuesday morning. The latest minimum central pressure reported by an air force reconnaissance aircraft was 992 millibars.
NASA's Quick Scatterometer satellite (QuikScat) observed Ida's winds by using microwaves to peer into the clouds. QuikScat can determine the speed of the rotating winds within the storm at the surface of the ocean. From a pass this morning at 6:23 a.m. ET, QuikScat confirmed that tropical storm force winds extend outward up to 200 miles from Ida's center. The National Hurricane Center's discussion noted that "A QuikScat pass around 12 UTC (7 a.m. ET) showed winds of 50-55 knots in the core...and assuming that the instrument did not quite resolve the maximum wind speed...the advisory intensity will be set to 60 knots."
The third satellite keeping an eye on Tropical Storm Ida, is the Geostationary Operational Environmental Satellite, GOES-12. GOES-12 captured Ida's movement over the last couple of days and the GOES Project at NASA created a movie of her tracks.
The GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. uses the data from the National Oceanic and Atmospheric Administration's Geostationary Operational Environmental (GOES) satellites to create images and movies. In this case, GOES-12 provided the data to make a movie of Ida's' movements from November 7-9, 2009.
While NASA satellites continue to watch from space, local hurricane statements (mostly tropical storm warnings) are in effect on the ground for residents of the Gulf coast from the Florida panhandle west to New Orleans and Baton Rouge, Louisiana. Those areas and northward into the eastern Tennessee Valley and southern Appalachians can expect 3 to 5 inches of rainfall, with isolated totals of 8 inches.
Tonight, however, residents along the immediate Gulf coast need to be done with preparations for storm surge. The National Hurricane Center noted that "Large and destructive waves will accompany a storm surge of 3 to 5 feet near the point of landfall."
Ida is predicted by the National Hurricane Center in Miami, Florida to hit the Gulf coast near Pensacola, Florida on Tuesday morning. Ida is expected to start its transition to non-tropical status after making landfall, and will then turn east.
For higher resolution movies from the GOES satellites, go to http://gsfc.nasa.gov/
Rob Gutro, NASA's Goddard Space Flight Center
NASA's TRMM Satellite Sees Most of Ida's Heaviest Rain Stayed off Coasts
NASA and the Japanese Space Agency's Tropical Rainfall Measuring Mission (TRMM) satellite flew over Ida and captured her rainfall when she passed by Nicaragua, Honduras and Belize this weekend. TRMM data revealed that most of the heaviest rainfall totals, as much as 11 inches, were just off the coasts of those countries, even though all of those areas dealt with flooding rains.
On November 6, 2009 at 1147 UTC (7:47 a.m. ET) TRMM revealed Ida had weakened to a tropical depression after coming ashore in eastern Nicaragua on November 5. TRMM identified the location of Ida's center of circulation and noted that much of the very heavy rainfall that occurred earlier had tapered off except for a few intense thunderstorms off the northeastern Honduras coast.
The National Hurricane Center in Miami, Florida predicted that Ida would blossom again into a tropical storm after moving into the Caribbean Sea off the coast of Honduras. Ida did enter Gulf of Mexico as a tropical storm, strengthened to a Category One Hurricane on the Saffir-Simpson Scale, and as of 10 a.m. ET on Monday, November 9, Ida had weakened to a Tropical Storm.
Ida's maximum sustained winds as of 10 a.m. ET on November 9 are now near 70 mph. Her center was located near 26.5N and 88.3W, and was moving north-northwest near 17 mph. Minimum central pressure is estimated near 996 millibars.
TRMM can be used to calibrate rainfall estimates from other satellites. The TRMM-based Multi-satellite Precipitation Analysis (TMPA) at the NASA Goddard Space Flight Center in Greenbelt, Md. monitors rainfall over the global Tropics. The TMPA rainfall analysis above shows that Ida produced heavy rainfall over large areas of eastern Nicaragua and Honduras. The highest rainfall totals of over 275 mm (~11 inches) were along the eastern Nicaragua coast as hurricane Ida came ashore.
Heavy rain amounts (from satellites) and flood potential calculations (from a hydrological model) are updated every three hours globally with the results shown on the "Global Flood and Landslide
Monitoring" TRMM web site pages at http://trmm.gsfc.nasa.gov
Hal Pierce, SSAI/Goddard Space Flight Center
The GOES-12 Satellite Sees Large Hurricane Ida Nearing Landfall
Residents of the U.S. Gulf coast thought they were getting a break this hurricane season until Ida showed up. Today, November 9, Ida is a hurricane and is headed for a landfall in the western Florida Panhandle after midnight. The Geostationary Operational Environmental Satellite, GOES-12 captured a look at Ida's extensive clouds this morning, and they stretch from Florida's west coast to eastern Texas. At 8:30 a.m. ET (7:30 CT), showers and thunderstorms had already spread into eastern Texas, Louisiana, southern Mississippi and Alabama and the Florida Panhandle.
Ida's cloud cover stretches a great distance and her winds also reach out far. Hurricane force winds extend outward up to 35 miles from the center and tropical storm force winds extend outward up to 200 miles from the center. That means that tropical storm-force winds cover an area of 400 miles from one end of the storm to the other. That's the distance from Boston, Massachusetts to Baltimore, Maryland!
The GOES-12 satellite provides many updates throughout the day, and is helping forecasters identify the extent and location of Ida on its track. GOES-12 is operated by the National Oceanic and Atmospheric Administration. NASA's GOES Project that creates GOES imagery is located at NASA's Goddard Space Flight Center, Greenbelt, Md.
The National Hurricane Center has already posted warnings and watches for Gulf coast residents. A hurricane warning remains in effect for the northern gulf coast from Pascagoula, Mississippi eastward to Indian Pass, Florida. A tropical storm warning and a hurricane watch remain in effect for the northern gulf coast from Grand Isle, Louisiana eastward to west of Pascagoula, Mississippi including New Orleans and Lake Pontchartrain. A tropical storm warning remains in effect for the northern gulf coast from east of Indian Pass, Florida to Aucilla River, Florida. Hurricane Warnings mean that hurricane conditions are expected within 24 hours in the warning area.
This morning at 7 a.m. ET (6 a.m. CT), Ida's maximum sustained winds were near 80 mph, making her a Category One hurricane on the Saffir-Simpson scale. She may hang on to hurricane strength when she makes landfall tonight after midnight. Although her center was 235 miles south-southeast of the mouth of the Mississippi River, near 25.8 North and 88.2 West, her cloud cover stretches over about one-third of the Gulf of Mexico! Ida's center is also about 330 miles south-southwest of Pensacola, Florida. Ida is moving north-northwest near 16 mph, and is expected to turn north, then northeast. Her minimum central pressure was 993 millibars this morning.
NASA's Aqua satellite's Atmospheric Infrared Sounder (AIRS) instrument captured an infrared image of Ida's extensive cloud cover and took the temperature of Ida's thunderstorm tops on November 8. Ida showed strong convective activity and high cold thunderstorms (in purple) that were as cold as -63F. Those high thunderstorms are indicative of heavy rainfall, and rainfall is going to be a major issue with Ida, and storm surge is expected between 4 and 6 feet above ground level along the coast. Large and destructive waves will accompany the storm surge.
The rainfall is expected between 3 and 6 inches with isolated amounts to 8 inches through Tuesday. Like Ida's winds, that rainfall forecast covers a large area from the Central and eastern Gulf Coast northward into the eastern portions of the Tennessee Valley and the southern Appalachian Mountains. As Ida moves inland and toward the northeast, heavy rainfall is forecast to move into Georgia, too. The National Weather Service already issued a flash flood watch for November 10 and 11 for north and central Georgia. Meteorologists are expecting 2-4 inches of rain there.
Texas, Louisiana, Mississippi, Alabama and western Florida are feeling the effects of Ida now. The National Weather Service in Pensacola, Florida has posted a Hurricane Wind Warning, Hurricane Warning, Flash Flood Watch and Coastal Flood Watch. Live National Weather Service Radar from Pensacola, Fla. can be found at: http://radar.weather.gov/radar.php?rid=MOB&product=NCR&overlay=11101111&loop=yes
Rob Gutro, NASA's Goddard Space Flight Center
November 06, 2009
Ida Eyeing the Yucatan This Weekend, Gulf Next Week
On Friday, November 6, Tropical Depression Ida was raining over eastern Honduras. The National Hurricane Center's forecast track brings Ida out into the western Caribbean and then near Mexico's Yucatan Peninsula over the weekend before taking it into the Gulf of Mexico.
By mid-week next week, Ida is expected to transform into an extra-tropical storm. Right now, the forecast track brings Ida in the direction of Florida's west coast, so residents there should be on guard.
At 10 a.m. ET on Friday, November 6, the airport at Puerto Lempira, Honduras reported rain with calm winds. Roatan also reported calm winds, but no rain and just overcast skies. A number of other cities and towns were also just reporting overcast skies, such as Amapala, Catacamas, Nueva Ocotepeque, Tela and Yoro.
Satellite imagery shows why those locations aren't reporting any rain. A visible satellite image from the Geostationary Operational Environmental Satellite, GOES-11 at 10 a.m. ET showed most of the clouds and rainfall associated with Ida are located to the northwest, north and northeast of the center of Ida's circulation. At 10 a.m. ET, the government of Honduras discontinued the tropical storm watch for the coast of Honduras from the Nicaragua/Honduras border to Limon.
At 10 a.m. ET, Tropical Depression Ida's maximum sustained winds remain near 35 mph, and some re-strengthening is expected after the center moves back over water. Ida's center was located near latitude 15.0 north...longitude 84.0 west or about 55 miles west of Cabo Gracias a Dios on the Nicaragua/Honduras border. Ida is moving north near 7 mph.
Ida is expected to turn north-northwest on Saturday, November 7 (because of a ridge of high pressure building in over the central Caribbean Sea) as it emerges in the northwestern Caribbean Sea. It is then forecast to brush past the Yucatan Peninsula bringing gusty winds and rains there on Sunday as it continues to move north.
Over the weekend, U.S. residents along the Gulf of Mexico should keep updated on the whereabouts and intensity of Ida as she makes her way north. Storm updates over the weekend can be found at the National Hurricane Center's Web site: http://www.nhc.noaa.gov
Rob Gutro, NASA's Goddard Space Flight Center
November 05, 2009
Ida Now a Hurricane and Moving to a Landfall in Nicaragua
Ida developed quickly yesterday from a tropical depression to a Category one hurricane. NASA satellite data yesterday revealed some powerful thunderstorms around the center of circulation, which gave forecasters clues that Ida was powering up.
At 7 a.m. EST on November 5, Ida had maximum sustained winds near 75 mph. Hurricane Ida's center was near latitude 12.8 north and longitude 83.4 west or about 60 miles north-northeast of bluefields Nicaragua and about 85 miles south of Puerto Cabezas, Nicaragua. Ida is moving toward the northwest near 7 mph and a gradual turn to the north-northwest with a slight decrease inforward speed is expected during the next day or two.
According to the National Hurricane Center, "On the forecast track, Ida will make landfall along the eastern coast of Nicaragua this morning and move across portions of eastern Nicaragua and eastern Honduras during the next couple of days.
Hurricane warnings are in effect in Nicaragua from Bluefields north to Puerto Cabezas. A Hurricane watch is in effect from Puerto Cabezas, Nicaragua north to the Honduras border. There are also tropical storm warnings for the Costa Rica / Nicaragua border to Bluefields, and from Puerto Cabezas north to the border with Honduras.
Rainfall is expected to be heavy, with totals at San Andres Island from 5 to 7 inches, with a maximum up to 12 inches. Eastern Nicaragua and eastern Honduras will get the brunt of the heavy rain, as 15 to 20 inches are expected with a maximum up to 25 inches! These rains are likely to cause life-threatening flashfloods and mudslides.
The coast isn't exempt either, as the 3-foot storm surge from Ida will bring large and battering waves.
The Geostationary Operational Environmental Satellite (GOES), GOES-11 captured a visible image of Hurricane Ida near the Nicaraguan coast today November 5. GOES is operated by the National Oceanic and Atmospheric Administration, and NASA's GOES Project, located at NASA's Goddard Space Flight Center, Greenbelt, Md. creates some of the GOES satellite images.
Once Ida makes landfall and starts moving over Nicaragua and Honduras, it could dissipate, however, some forecast models project that it will survive and move back into the Gulf of Mexico.
Rob Gutro, NASA's Goddard Space Flight Center
November 04, 2009
NASA Satellites See Tropical Depression 11 Form in Western Caribbean
The eleventh tropical depression formed this morning in the far western Caribbean, and it is already forecast to make a landfall. NASA's TRMM and Aqua satellites already noticed that there are some strong thunderstorms and heavy rainfall within Tropical Depression 11, and residents of eastern Nicaragua and eastern Honduras can expect those conditions.
At 1 p.m. EST the center of tropical depression eleven (TD11) was located near latitude 11.8 north...longitude 82.3 west or about 65 miles southwest of San Andres island and about 100 miles east of Bluefields, Nicaragua. The depression has maximum sustained winds near 35 mph, and may strengthen to a tropical storm later today. TD11 is moving west-northwest near 7 mph, however it is expected to slow down and move toward the northwest bringing its center near the east coast of Nicaragua this evening. The estimated minimum central pressure is 1006 millibars.
A tropical storm warning remains in effect for the entire eastern coast of Nicaragua and for the islands of San Andres and Providencia. A tropical storm warning means that tropical storm conditions are expected somewhere within the warning area within 24 hours.
Data from the Tropical Rainfall Measuring Mission (TRMM) satellite during the early morning hours of November 4 were used in making the rainfall analysis at NASA's Goddard Space Flight Center in Greenbelt Md. The rainfall analysis showed strong thunderstorms with heavy rainfall, especially around the center of circulation. Looking at TRMM data, the forecasters at the National Hurricane Center noted that "The depression is expected to produce total rainfall accumulations of 5 to 7 inches over San Andres Island with maximum amounts of 12 inches possible. Rainfall accumulations of 15 to 20 inches are expected over eastern Nicaragua and eastern Honduras with maximum amounts of 25 inches possible. These rains could produce life-threatening flash flood and mud slides."
NASA's Aqua satellite captured TD11 on November 4 at 2:35 a.m. ET from the Atmospheric Infrared Sounder (AIRS) instrument. AIRS measures cloud temperature using infrared light. In NASA's infrared imagery, the false-colored purple clouds are as cold as or colder than 220 Kelvin or minus 63 degrees Fahrenheit (F). The blue colored clouds are about 240 Kelvin, or minus 27F. The colder the clouds are, the higher they are, and the more powerful the thunderstorms are that make up the cyclone and Tropical Depression 11 has some high thunderstorms with temperatures as cold as minus 63 degrees Fahrenheit (F), especially near its center. That's one indication that the storm may indeed already have strengthened to tropical storm status. Hurricane hunter aircraft from the National Oceanic and Atmospheric Administration will be flying over the storm today to confirm its strength.
The depression is currently in an environment with light wind shear and warm waters, which are helping to power it. In the meantime, residents of eastern Nicaragua and eastern Honduras need to prepare for flooding rains.
Rob Gutro, NASA's Goddard Space Flight Center