[image-220][image-236]NASA Sees Hurricane Cristobal Racing Through North Atlantic
Satellite imagery shows Hurricane Cristobal racing through the North Atlantic on Friday, August 29 while losing its tropical characteristics. An image from NOAA's GOES-East satellite showed Cristobal headed south of Greenland. The previous day, NASA's TRMM satellite saw heavy rainfall occurring in the hurricane.
In a visible image from NOAA's GOES-East satellite on August 29 at 7:45 a.m. EDT, Hurricane Cristobal was moving through the North Atlantic about 500 miles southwest of Greenland. The image was created by the NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
At 5 a.m. EDT (0900 UTC) on August 29, Cristobal's maximum sustained winds were near 80 mph (130 kph). The National Hurricane Center forecast noted that Cristobal is forecast to lose its tropical characteristics later today, but it should remain a powerful extra0tropical cyclone over the North Atlantic through Sunday, August 31.
The center of Hurricane Cristobal was located near latitude 42.1 north and longitude 51.7 west. Cristobal was moving toward the northeast near 49 mph (80 kph) and is expected to continue in that direction while slowing down. The estimated minimum central pressure is 973 millibars.
The TRMM Satellite Sees Heavy Rainfall in Cristobal
On the previous day, NASA and the Japan Aerospace Exploration Agency's Tropical Rainfall Measuring Mission (TRMM) satellite had a very good view of Cristobal on August 28 at 12:58 UTC (8:58 a.m. EDT) as the hurricane passed well to the northwest of Bermuda.
At NASA Goddard, rainfall data derived from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data was overlaid on a visible/infrared image from NOAA's GOES-East satellite taken August 28 at 1300 UTC (9 a.m. EDT). TRMM PR found some intense thunderstorms producing rain at a rate of almost 78 mm (about 3.1 inches) per hour in a band of precipitation feeding into Cristobal's southeastern side.
The TRMM satellite was close to reaching its northern most coverage when the satellite flew over on August 28, 2014. TRMM covers the tropics, and Cristobal was moving out of range when TRMM captured data on it. The GPM satellite launched by NASA and JAXA on Feb. 27, 2014 will continue viewing hurricane Cristobal as the tropical cyclone moves farther north over the open waters of Atlantic Ocean.
Headed to the United Kingdom
The U.K. Meteorological Service (UKMS) forecast for Cristobal calls for the storm to move northeast across the Atlantic toward Iceland, staying well away from the U.K. The UKMS noted that Cristobal could bring stronger winds across northwestern parts of Scotland and rain across the United Kingdom on Sunday, August 31 and Monday, September 1.
Text credit: Rob Gutro
NASA's Goddard Space Flight Center
[image-174][image-190][image-206]Aug. 27, 2014 - NASA's TRMM Analyzes Hurricane Cristobal
NASA's Tropical Rainfall Measuring Mission or TRMM Satellite provided a look under the hood of Hurricane Cristobal as it continues moving north and paralleling the U.S. East Coast. NASA's HS3 hurricane mission also investigated the storm. Cristobal is now close enough to the coast to trigger high surf advisories.
On August 28, the National Weather Service issued an advisory for high surf of 6 to 12 feet and rip currents on the southern coasts of Rhode Island and Massachusetts, including Cape Cod and the nearby islands of Martha’s Vineyard and Nantucket.
Cristobal, still a minimal Category 1 hurricane on the U.S. Saffir-Simpson scale, has been slowly making its way northward up from the southeastern Bahamas on a track generally parallel to the eastern seaboard. The storm now appears poised to recurve away from the U.S. East Coast and head for the central Atlantic as it begins to feel the effects of an approaching shortwave trough (elongated area of low pressure) embedded in the westerlies (winds) that are moving eastward out of the Great Lakes Region.
NASA's airborne Hurricane and Severe Storm Sentinel, or HS3, mission kicked off on August 27 when one of the remotely piloted Global Hawk aircraft flew a "lawnmower" or back and forth pattern over Hurricane Cristobal while gathering data using dropsondes and two other instruments. The Global Hawk dropped 81 dropsondes over Cristobal. A dropsonde is a device that measures winds, temperature, pressure and humidity as it falls from the aircraft to the surface.
The TRMM satellite passed over Hurricane Cristobal on August 27 at 12:16 UTC (8:16 a.m. EDT). TRMM is a joint mission between NASA and the Japanese space agency JAXA.
At the time TRMM flew overhead, Cristobal's center was located about 330 miles (531 km) southeast of Cape Hatteras, North Carolina and approximately 420 miles (675.9 km) west-southwest of Bermuda. At this time, an eye was still apparent in TRMM's infrared imagery, but the rain intensities from TRMM showed that there is only a partial eyewall, which is indicated by the band of moderate intensity rain along the northern edge of the storm's center. Several long rainbands of mostly light to moderate rain wrapped mainly around the eastern side of the storm and are evidence of the storm's large cyclonic circulation.
Those rainbands are very well defined in a 3-D image of Cristobal (taken at the same time) that was created at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The 3-D image showed the height of precipitation echoes within the storm courtesy of the TRMM Precipitation Radar instrument. Cristobal didn't appear round and symmetric in either clouds or rainfall which suggests that the hurricane is being battered by southwesterly wind shear ahead of the approaching shortwave trough (elongated area) of low pressure. The National Hurricane Center (NHC) expects that the trough should begin to steer the storm in a more northeasterly direction. At the time of this image, Cristobal's sustained winds were reported at 70 knots (80.5 mph/129.6 kph) and the storm was still moving north at 12 mph (19.3 kph).
By August 28 at 8 a.m. EDT (1200 UTC) the center of Hurricane Cristobal was located near latitude 36.3 north and longitude 67.0 west. Maximum sustained winds remain near 75 mph (120 kph) and no significant change in strength is forecast during the next two days.
Cristobal was moving toward the northeast near 26 mph (43 kph) and that general motion with an increase in forward speed is expected over the next 48 hours. On the forecast track, the NHC noted that the center of Cristobal will rapidly move toward the North Atlantic well northwest of Bermuda and pass well south of Nova Scotia later in the day today, August 28.
With the system now devoid of heavy rain and approaching cooler waters, Cristobal should start to lose its tropical characteristics and transition into an extra-tropical storm over the next few days. The NHC expects Cristobal to become a powerful extra-tropical cyclone over the North Atlantic by Friday night, August 29.
Text credit: Stephen Lang
SSAI/NASA Goddard Space Flight Center
Aug. 28, 2014 - Update #1 - NASA's TRMM Satellite Adds Up Cristobal's Heavy Rainfall in the Caribbean[image-79]
The Caribbean Islands of Turks and Caicos were drenched from Tropical Storm Cristobal before the storm moved north and intensified into a hurricane. NASA's TRMM satellite added up the rainfall and revealed the soaking those islands received.
The Tropical Rainfall Measuring Mission or TRMM satellite is like a flying rain gauge in space. It can estimate rainfall throughout storms on Earth from its orbit around the planet. TRMM is managed by both NASA and the Japan Aerospace Exploration Agency known as JAXA and has been in orbit since 1997 covering the tropics.
At NASA's Goddard Space Flight Center in Greenbelt, Maryland the data from TRMM was to create a TRMM-based, near-real time Multi-satellite Precipitation data (TMPA) Analysis. That analysis basically added up the rainfall associated with Tropical Storm Cristobal during the period from August 18-25, 2014. The TMPA showed flooding rainfall over the islands of the Caribbean and the Turks and Caicos Islands.
The TMPA showed heavy rainfall over the Dominican Republic and Puerto Rico that exceeded 275 mm (10.9 inches). The greatest rainfall totals during that period was found along Cristobal's track near the Turks and Caicos Islands where rainfall was over 350mm (13.8 inches).
After drenching the eastern Caribbean, Cristobal moved north and intensified into a hurricane where it passed to the west of Bermuda.
Text credit: Hal Pierce/Rob Gutro
NASA's Goddard Space Flight Center
[image-128][image-144]Aug. 27, 2014 - NASA's TRMM Satellite Sees Powerful Towering Storms in Cristobal
NASA's TRMM satellite identified areas of heavy rainfall occurring in Hurricane Cristobal as it continued strengthening on approach to Bermuda.
NASA's Tropical Rainfall Measuring Mission or TRMM satellite flew above Hurricane Cristobal on August 26 at 11:35 UTC (7:35 a.m. EDT) gathering rainfall data. A rainfall analysis derived from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) data instruments were overlaid on visible/infrared image from NOAA's GOES-East satellite to create a total picture of the storm. The image was made at NASA's Goddard Space Flight Center in Greenbelt, Maryland. NASA and the Japan Aerospace Exploration Agency manage TRMM.
When TRMM captured that rainfall data, Cristobal was a category one hurricane with sustained winds estimated to be slightly above 65 knots (about 75 mph). Cristobal didn't have a clearly defined eye because vertical wind shear was still affecting the tropical cyclone's appearance and pushing clouds and storms away from the center. TRMM PR and TMI rainfall data found heavy rain to the northeast of Cristobal's center and in intense convective storms within a feeder band streaming in from the southwest. Some of the powerful storms in the feeder band were found by TRMM PR to be dropping rain at a rate of 133.8 mm (5.2 inches) per hour.
TRMM's Precipitation Radar (PR) reflectivity data were used to create a 3-D view of precipitation within the feeder band (band of thunderstorms wrapping into the center) south of Cristobal's center. Those data showed that some energetic storms in this band were reaching heights of over 15km (about 9.3 miles) and were generating heavy rain.
Satellite imagery on August 27 showed some strong thunderstorms had redeveloped near the center of Cristobal mainly in the western semicircle. Satellite imagery also showed that dry air was wrapping south and east of the center.
At 11 a.m. EDT on Wednesday, August 27, Cristobal's maximum sustained winds were near 80 mph (130 kph) and some strengthening is possible. It was centered near latitude 31.8 north and longitude 72.2 west. That puts the center of Cristobal about 435 miles (700 km) west of Bermuda and even closer to Cape Hatteras, North Carolina at 300 miles (485 km) to the Cape's southeast.
Cristobal has a large wind field where hurricane force winds extend outward from the center up to 60 miles (95 km) and tropical storm force winds extend outward up to 205 miles (335 km). The estimated minimum central pressure is 983 millibars.
Cristobal is moving toward the north near 12 mph (19 kph) and the National Hurricane Center (NHC) expects a turn to the northeast. NHC noted that the center of Cristobal will pass well northwest of Bermuda late on August 27 and stay away from the U.S. and Canadian mainland on its track to the North Atlantic Ocean.
Cristobal is expected to become a powerful extra-tropical cyclone over the north Atlantic by Friday, August 29.
Text credit: Hal Pierce/Rob Gutro
SSAI/NASA's Goddard Space Flight Center
[image-63][image-96][image-112]Aug. 26, 2014 - NASA's TRMM and Aqua Satellites Gaze into Hurricane Cristobal
NASA's TRMM and Aqua satellites have been providing views of the outside and inside of Hurricane Cristobal as it heads for Bermuda. The National Hurricane Center posted a Tropical Storm Watch for Bermuda as Cristobal heads in that direction.
Strong winds and flooding associated with Tropical Storm Cristobal caused deaths in the Dominican Republic, Haiti, and Jamaica. The Tropical Rainfall Measuring Mission or TRMM satellite captured rainfall data from Cristobal on August 24, 2014 at 1150Z (7:50 a.m. EDT). Light to moderate rainfall was occurring throughout much of the depression, with the exception of an area of heavy rainfall in the southeastern Bahamas where rain rates exceeded 2 inches/50 mm per hour. At that time Cristobal was a tropical depression, and shortly after TRMM passed overhead, Tropical Depression Four was upgraded to tropical storm status.
The next day, on August 25, 2014 at 1230 UTC (8:30 a.m. EDT). Cristobal encountered strong wind shear and the center appeared rain-free on TRMM satellite imagery. TRMM found that most of the intense rain was falling at a rate of over 159.3 mm (about 6.3 inches) per hour in a line of storms that was located well to the northeast of Cristobal's center.
On Aug. 25 at 18:10 UTC (2:10 p.m. EDT) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite captured a visible image of Tropical Storm Cristobal over the Bahamas. In the image, it is clear that strong wind shear had pushed thunderstorms northeast of Cristobal's center. Despite the wind shear, Cristobal maintained hurricane force.
On August 26 at 11 a.m. EDT as Cristobal continued moving north, NOAA buoy 41047 which is located just north of the storm's center at time, reported a sustained wind of 45 mph (72 kph) and a wind gust of 51 mph (83 kph).
At 11 a.m. EDT on August 26, Cristobal's maximum sustained winds were near 75 mph (120 kph) and the National Hurricane Center expects some strengthening. The center was located near latitude 27.2 north and longitude 71.7 west. That's about 545 miles (875 km) southwest of Bermuda. Cristobal is moving toward the north near 12 mph (19 kph) and a northward to north-northeastward is expected to continue through tonight, followed by turn to the northeast on Wednesday, August 27.
On the forecast track, the National Hurricane Center expects that the center of Cristobal will pass northwest of Bermuda on Wednesday.
Text credit: Rob Gutro/Hal Pierce
SSAI/NASA Goddard Space Flight Center
Aug. 25, 2014 - Satellites Capture the Birth and Movement of Tropical Storm Cristobal[image-36]
The third tropical storm of the Atlantic hurricane season formed near the southeastern Bahamas on Sunday, August 24. NASA's Aqua satellite and NOAA's GOES-East satellites provided imagery of the storm's birth and movement.
System 96L lingered in the eastern Caribbean over the last couple of days and on Saturday, August 23, became a tropical depression. That depression strengthened into a tropical storm during the morning of August 24. A GOES-East satellite image was taken at 9:30 a.m. EDT on August 24 showed Cristobal as a rounded area of clouds north of Hispaniola (Haiti and the Dominican Republic) moving into the southeastern Bahamas. The GOES image was created at NASA's GOES Project office in NASA's Goddard Space Flight Center in Greenbelt, Maryland.
Upon its birth Cristobal had sparked Tropical Storm Warnings for Southeastern Bahamas, Including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, the Ragged Islands, as well as the Turks and Caicos Islands, Central Bahamas, Including Cat Island, The Exumas, Long Island, Rum Cay, and San Salvador.
[image-51]At 8 a.m. EDT on August 24, Cristobal's maximum sustained winds were near 45 mph (75 kph). The center of Tropical Storm Cristobal was located near latitude 23.0 north and longitude 73.0 west. That put the center just 40 miles (60 km) north of Mayaguana Island. A day later, Monday, August 24, Cristobal was still dropping heavy rainfall over the Turks and Caicos Islands as it moved slowly and erratically to the north-northeast.
Heavy rainfall is a problem for the islands because Cristobal is moving so slowly. The National Hurricane Center noted that the tropical storm is expected to produce rainfall totals of 4 to 8 inches over the Turks and Caicos as well as portions of the southeastern and central Bahamas through Tuesday, with isolated amounts around 12 inches possible. Minor flooding was already reported during the morning of August 25 near Pirates Cove on Mayaguana Island.
On August 24 at 15:55 UTC (11:55 a.m. EDT) Cristobal's center appeared near Turks and Caicos Islands in this visible image from the Moderate Imaging Resolution Spectroradiometer (MODIS) instrument aboard NASA's Terra satellite. In the MODIS image, it appeared that northerly wind shear was affecting the storm, blowing most of the strongest clouds and thunderstorms south of the center.
By August 25, the wind shear had not let up. The National Hurricane Center described the storm as remaining sheared with the low-level center fully exposed on the north side of the "deep convective cloud mass (the area of the strongest thunderstorms)."
At 11 a.m. EDT (1500 UTC) Cristobal was centered about 120 miles (195 km) east-northeast of San Salvador Island, Bahamas, and 715 miles (1,150 km) southwest of Bermuda. That puts the center of Tropical Storm Cristobel near latitude 24.6 north and longitude 72.7 west. Cristobal's maximum sustained winds were near 60 mph (95 kph) and some strengthening is expected over the next two days. Cristobal is moving toward the north-northeast near 2 mph (4 kph) and is expected to turn northeast and speed up on Tuesday.
The government of Bahamas has discontinued the tropical storm warning for the central Bahamas.
The National Hurricane Center noted that a strong, elongated area of low pressure (a trough) just of the U.S. east coast is forecast to capture Cristobal and gradually lift out the cyclone to the northeast.
Text credit: Rob Gutro
NASA's Goddard Space Flight Center