LOADING...
Text Size
Julio (Eastern Pacific)
August 15, 2014

[image-398]NASA Sees No Punch Left in Tropical Storm Julio

Tropical Storm Julio doesn't have any strong thunderstorms or strong convection left in it according to infrared satellite imagery from NASA.

When NASA's Aqua satellite passed over Tropical Storm Julio on August 14 at 12:23 UTC (8:23 a.m. EDT), the Atmospheric Infrared Sounder known as AIRS analyzed the clouds and temperatures of the storm. The AIRS data showed that cloud tops had warmed and dropped lower in the atmosphere. That indicates that the strength behind rising air had weakened and was not forming strong, high thunderstorms with cold cloud tops.

There was a small area of cold cloud tops just southeast of the center of circulation where temperatures were near 230 kelvin (-43.1C/ -45.6F). That indicated the strongest storms in the tropical cyclone. Cloud top temperatures throughout the rest of the storm were warmer and weaker.

NOAA's Central Pacific Hurricane Center (CPHC) noted that the system remained devoid of strong convection (rising air that forms thunderstorms that make up a tropical cyclone) on August 15. That's because there was moderate vertical wind shear battering the storm, and Julio was continuing movement over increasingly cooler sea surface temperatures. Sea surface temperatures of at least 80F (26C) are needed to maintain the strength and Julio is moving north into temperatures below that threshold, which will continue to weaken it. CPHC noted that with no deep convection near the center to fuel the system, Julio is expected to continue weakening and lose its tropical characteristics.

Julio is so far from Hawaii and any land areas that there are no coastal watches or warnings in effect.

On August 15 at 0900 UTC (5 a.m. EDT) the center of Tropical Storm Julio was located near latitude 32.4 north and longitude 157.3 west, about 765 miles (1,235 km) north of Honolulu, Hawaii. Maximum sustained winds were near 45 mph (75 kph) but weakening. Julio is moving toward the north-northeast near 5 mph (7 kph). Julio is expected to turn toward the north, then toward the northeast over the next two days.

Julio is forecast to weaken to a tropical depression later on August 15, and a remnant low pressure areas before the day's end.  

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


Aug. 14, 2014 - NASA Sees Tropical Storm Julio Now Far From Hawaii[image-253]

Hurricane Julio moved past the Hawaiian Islands like a car on a highway in the distance, and NASA's Terra satellite captured an image of the storm, now downgraded to a tropical storm located more than 700 miles away. Julio is far enough away from Hawaii so that there are no coastal watches or warnings in effect.

On August 13 at 21:10 UTC (5:10 p.m. EDT), the Moderate Resolution Imaging Spectroradiometer of MODIS instrument aboard NASA's Terra satellite captured a visible image of Hurricane Julio moving through the Central Pacific Ocean. The visible image shows that powerful thunderstorms still circled the center of the storm, and that Julio still had an eye, although somewhat obscured by clouds. Bands of thunderstorms continued to wrap into the center of circulation from the eastern side of the storm.

On August 14 at 5 a.m. HST (11 a.m. EDT/1500 UTC) the center of Tropical Storm Julio was located near latitude 31.6 north, longitude 158.5 west. That puts the center about 710 miles (1,145 km) north of Honolulu Hawaii. Maximum sustained winds are near 65 mph (100 kph) and weakening is forecast through Saturday morning, August 16.  Julio was moving toward the northeast near 5 mph (7 kph) and is expected to turn north by August 15, according to NOAA's Central Pacific Hurricane Center (CPHC). 

Today, August 14, satellite data showed that wind shear had begun taking its toll on Julio. The CPHC noted "deep convection (rising air that forms thunderstorms that make up the tropical storm) associated with Julio has been pushed away more than 60 nautical miles to the south of the low-level center."

CPHC expects Julio to weaken to a post-tropical depression over the weekend of August 16 and 17.

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


Hurricane Julio and Two Tropical Lows "Bookend" Hawaii[image-237]

Infrared satellite imagery from NOAA's GOES-West satellite shows three tropical systems in the Central Pacific Ocean that appears like bookends with Hawaii in-between.

In an infrared image from the GOES-West satellite taken August 13 at 1200 UTC (8 a.m. EDT/2 a.m. HST), Hurricane Julio lies to the north of Hawaii, while two low pressure areas lie to the southeast of the island state. The image was created by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

On August 13 at 0900 UTC (5 a.m. EDT/11 p.m. HST on Aug.12) the center of Hurricane Julio was located near latitude 30.0 north, longitude 158.4 west. That's about 600 miles (970 km) north of Honolulu, Hawaii. Julio was moving toward the north-northwest near 7 mph (11 kph). NOAA's Central Pacific Hurricane Center (CPHC) expects Julio to gradually turn toward the north, then to the northeast. Maximum sustained winds were near 75 mph (120 kph). The estimated minimum central pressure is 988 millibars. There are no watches or warnings in effect for Hawaii.

The Central Pacific Hurricane Center noted that vertical wind shear should begin to affect the hurricane by Thursday, August 15 as Julio tracks into cooler waters. The combination of those two factors is expected to weaken Julio to tropical storm status as it turns to the northeast over open waters in the Central Pacific Ocean.

Far to the southeast of Julio and southeast of the Hawaiian Islands are two slowly developing areas of tropical low pressure.

The first area is a disorganized area of showers and thunderstorms, and is located along a trough (elongated area) of low pressure about 950 miles southeast of Hilo, Hawaii. This system is expected to develop slowly, or not at all, as it moves west-northwest at 10 to 15 mph. The CPHC gives it just a 10 percent chance of becoming a tropical depression in the next two days. 

The second area is an elongated area of low pressure, generating showers and thunderstorms. That low is centered about 1380 miles east-southeast of Hilo, Hawaii and is in the westernmost fringe of the Eastern Pacific Ocean. CPHC said that this system may develop slowly as it moves west-northwest at 10 to 15 mph. If it does develop, this system may enter the central Pacific basin as early as tonight, August 13. CPHC gives the second low a 20 percent chance of formation over the next two days.

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


Aug. 12, 2014 - NASA Sees a Weaker Tropical Storm Julio Far North of Hawaii[image-221]

Tropical Storm Julio continues to weaken as it moves through cooler waters of the Central Pacific Ocean. NASA's Terra satellite passed over Julio and saw that the bulk of the clouds and precipitation were being pushed to the34 north of the center as the storm tracked far north of the Hawaiian Islands.

NASA's Terra satellite passed over Julio on August 11 at 21:25 UTC (5:25 p.m. EDT) and the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard took a visible picture of the storm. The MODIS image revealed a circular center, but most of the clouds and showers associated with the storm were pushed north of the center. Drier air, located over the southern quadrant of the storm is sapping the development of thunderstorms.

Julio tracked far enough away from the Hawaiian Islands so that no watches or warnings were generated for the storm.

At 5 a.m. HST local time (1500 UTC/11 a.m. EDT) on August 12, the center of Tropical Storm Julio was located near latitude 28.6 north, longitude 157.1 west, about 505 miles (815 km) north of Honolulu Hawaii. Julio was moving toward the northwest near 6 mph (9 kph) and NOAA's Central Pacific Hurricane Center (CPHC) expects that motion to continue over the next day before the storm gradually turns north.  Maximum sustained winds were near 65 mph (100 kph) and a slow weakening is forecast over the next two days.

The CPHC expects that cooler waters and increasing wind shear will weaken Julio into a depression by August 14.

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


Aug. 11, 2014 - Julio Embarking on Weakening Trend[image-205]

The Central Pacific Hurricane Center has issued its 30th warning on Julio today at 1500 GMT.  Julio's position at this point is 395 miles northeast of Honolulu, Hawaii moving northwest at 8 knots per hour.  Julio is moving toward the northwest near 9 mph, 15 km/h. Maximum sustained winds are near 75 mph, 120 km/h, with higher gusts. Julio is expected to weaken slightly over the next 48 hours, down to tropical storm strength by tonight.

At present, hurricane force winds extend outward up to 25 miles, 35 km, from the center, and tropical storm force winds extend outward up to 155 miles, 250 km.

Julio is moving northwest and has embarked on a weakening trend. The storm is anticipated to pass to the north of the Hawaiian islands.  Julio is expected to continue moving northwest through Wednesday, then gradually turn north into the open Pacific.  Large swell will produce dangerous surf conditions on east coasts of most Hawaiian islands.

Text credit: Lynn Jenner
NASA's Goddard Space Flight Center


Aug. 10, 2014 - Julio Slowing Down As It Moves North of Hawaii[image-173]

At 1100 pm HST, 0900 UTC, the center of hurricane Julio was located near latitude 22.8 north, longitude 151.3 west. Julio is moving toward the northwest near 16 mph, 26 km/h. This general northwestward motion is expected to continue through Monday evening. However, Julio is forecast to begin moving at a slower forward speed starting Sunday or Sunday night. Along this forecast track, Julio will be northeast and then north of the main Hawaiian islands during the next two days.  Estimates have Julio being downgraded to a strong tropical storm by Monday night.

Recent satellite data imagery shows Julio's ragged eye which is intermittently cloud filled.  Most often a result of hostile conditions within the hurricane due to vertical wind shear.

[image-189]Maximum sustained winds are near 90 mph, 150 km/h, with higher gusts. Some gradual weakening is forecast during the next couple of days, but Julio is expected to remain a hurricane through early Monday. Julio may weaken to a strong tropical storm by late Monday.

Hurricane force winds extend outward up to 35 miles, 55 km, from the center, and tropical storm force winds extend outward up to 160 miles, 260 km.  Swells generated by hurricane Julio will produce large surf along most north and east facing shores of the main Hawaiian islands through Monday.

Text credit:  Lynn Jenner
NASA's Goddard Space Flight Center


Aug. 09, 2014 - NASA's Aqua Satellite Captures Julio's Final Approach [image-157]

After Iselle's direct hit on the islands, weather conditions will gradually improve on Saturday, then Julio will approach the islands from the east Sunday.  Julio may approach the island chain late Saturday into Sunday as the storm keeps moving west northwest at 16 mph across the central Pacific. The latest National Hurricane Center bulletin on Julio locates the hurricane about 680 miles E of Hilo.

Maximum sustained winds are near 100 mph, 155 km/h, with higher gusts. Some weakening is forecast during the next couple of days, but Julio is forecast to remain a hurricane into Sunday night.  Hurricane force winds extend outward up to 35 miles, 55 km, from the center, and tropical storm force winds extend outward up to 175 miles, 280 km.

The forecast shows Julio passing a couple of hundred miles NE of the Big Island on Sunday. However, with any tropical storm, tracks can change and continued monitoring of the storm is advised.

Text credit:  Lynn Jenner
NASA's Goddard Space Flight Center


Aug. 08, 2014 (#2) - TRMM Satellite Views Hurricane Julio

[image-204][image-141]The TRMM satellite had a good view earlier of hurricane Julio on August 8, 2014 at 0017 UTC. Julio was still a very powerful intensifying hurricane with winds of over 90 kts (about 104 mph). Rainfall derived from TRMM's TMI and PR are shown overlaid on a GOES-WEST 0030 UTC Visible/Infrared image. Julio's nearly clear circular eye was evidence of the powerful winds within the category 2 hurricane.

TRMM's Precipitation Radar (PR) instrument measured rain falling at a rate of almost 89 mm (about 3.5 inches) per hour in powerful storms south of Julio's center. A 3-D view using data from TRMM PR shows that Julio was apparently undergoing an eye wall replacement at the time of this view. A moat like gap is shown separating an inner eye wall from the replacement outer eye wall. A hurricane usually weakens when this is happening but when the outer eye wall replaces the inner one the storm can intensify again.

Hurricane Julio is predicted to weaken to a tropical storm when passing to the north of the Hawaiian islands in about three days.

Text credit: Hal Pierce
NASA's Goddard Space Flight Center

 

 

 


[image-238][image-254][image-270]Aug. 08, 2014 (#1) - TRMM and GOES Satellites See Hurricanes Iselle and Julio Menacing Hawaii

The Tropical Rainfall Measuring Mission or TRMM satellite and NOAA's GOES-West satellite saw both weakening Hurricane Iselle and category two hurricane Julio at the same time on August 7 from its orbit in space because both storms are so close to each other in the Central Pacific Ocean.

Both Iselle and Julio were moving toward the Hawaiian Islands on August 7, 2014 at 0922 UTC (5:22 a.m. EDT) when TRMM passed overhead. TRMM's Microwave Imager (TMI) instrument collected data as it passed overhead. Microwave brightness temperatures at 85.5 GHZ and at 37.0 GHZ were combined in the red, green and blue components to construct the image. Brightness temperature is a measurement of the radiance of the microwave radiation traveling upward from the top of the atmosphere to the satellite. The brighter the temperature, the more energy is being generated.

NOAA's GOES-West satellite captured an image of both storms on August 7 at 1800 UTC (2 p.m. EDT) as Iselle was approaching Hawaii and Hurricane Julio followed behind to the east. In the image, Julio appeared to have a better, more organized circulation.

At 500 am HST, 1500 UTC, the center of hurricane Julio was located near latitude 18.2 north, longitude 141.9 west. Julio is moving toward the west-northwest near 16 mph, 26 km/h, and a general westward to west-northwestward motion is expected to continue through Sunday morning.

Maximum sustained winds are near 105 mph, 165 km/h, with higher gusts. Gradual weakening is expected through Sunday morning.

Hurricane force winds extend outward up to 35 miles, 55 km, from the center, and tropical storm force winds extend outward up to 115 miles, 185 km.

The estimated minimum central pressure is 966 mb, 28.53 inches.

For updated forecasts on Iselle, please visit NOAA's Central Pacific Hurricane Center website at: http://www.prh.noaa.gov/cphc/tcpages/ISELLE.php. For updated forecasts on Hurricane Julio, please visit NOAA's National Hurricane Center website: www.nhc.noaa.gov.

Text credit:  Hal Pierce / Lynn Jenner
NASA's Goddard Space Flight Center

 

 

 

 

 

 

 


Aug. 7, 2014 - NASA Sees Hurricane Julio Organize and Emit a Gamma-Ray Flash  

[image-109]NASA's Fermi and Aqua satellites captured two different views of bursts of strength show by Hurricane Julio as it intensified. NASA's Fermi satellite saw a gamma-ray flash from Julio, while NASA's Aqua satellite saw Julio become more structurally organized as a hurricane.

Fermi Spots Julio's Gamma-Ray Flash

Shortly after 4:19 a.m. EDT on Monday, Aug. 4, NASA's Fermi Gamma-ray Space Telescope showed that Julio packs a wallop of a very different kind when its Gamma-ray Burst Monitor (GBM) detected a quick flash of high-energy light.

[image-125]This type of outburst is known as a terrestrial gamma-ray flash (TGF). Produced by the powerful electric fields in thunderstorms, TGFs last only a few thousandths of a second but emit gamma rays that make up the highest-energy naturally-occurring light on Earth. Scientists estimate that, on average, about 1,100 TGFs occur each day.

Fermi's GBM instrument can detect TGFs within about 500 miles (800 km) of the spacecraft, which is too imprecise to definitively associate these flashes with specific storms. In 2012, however, Fermi scientists used lightning location data to show that TGFs also emit strong radio bursts, signals that can pinpoint the flashes with much greater precision.

Lightning emits a broad range of very low frequency (VLF) radio waves, often heard as pop-and-crackle static on AM radio broadcasts. The World Wide Lightning Location Network (WWLLN), a research collaboration operated by the University of Washington in Seattle, uses these radio signals to pinpoint lightning discharges anywhere on the globe to within about 6 miles (10 km).

According to WWLLN data, a lightning-like radio burst occurred near Fermi just 1.89 milliseconds after the spacecraft captured the gamma-ray flash above Julio, then a tropical storm. The timing is so close that the two signals must be related. "As far as I know, a TGF from a tropical storm has never been reported before," said Michael Briggs, a member of the GBM team at the University of Alabama in Huntsville.

Aqua Spots a More Organized Storm 

Two days after Julio emitted a gamma-ray flash, NASA's Aqua satellite passed overhead and captured a visible image of the storm that showed it had become more structurally organized.

On August 6 at 22:30 UTC (6:30 p.m. EDT) NASA's Aqua satellite passed over Hurricanes Iselle and Julio approaching Hawaii. The visible image was captured from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument. The hurricane appeared more compact and symmetric. By August 7, the National Hurricane Center noted that Julio's eye had cleared of clouds.

At 5 a.m. EDT (0900 UTC) on August 7, the National Hurricane Center (NHC) noted that Julio's maximum sustained winds had increased to near 100 mph (155 kph). The
NHC noted that some additional strengthening is possible before the storm begins gradually weakening at night and over the weekend of August 9 and 10.

The eye of Hurricane Julio was located near latitude 16.8 north and longitude 134.9 west, about 1,340 miles (2,155 km east of Hilo, Hawaii. Julio is moving toward the west-northwest near 17 mph (28 kph) and this general motion is expected to continue for the next 48 hours. The estimated minimum central pressure is 976 millibars.

The NHC intensity forecast calls for Julio to remain at hurricane strength for the next 2-3 days (through August 9 or 10). Only gradual weakening is anticipated at the end of the forecast period since Julio will be moving over increasingly warmer waters to the north and west of Hawaii.

Related Links:

Fermi Improves its Vision for Thunderstorm Gamma-Ray Flashes (12.06.2012) - http://www.nasa.gov/mission_pages/GLAST/news/vision-improve.html
NASA's Fermi Catches Thunderstorms Hurling Antimatter into Space (01.10.2011) - http://www.nasa.gov/mission_pages/GLAST/news/fermi-thunderstorms.html

Text credit:  Francis Reddy / Rob Gutro
NASA's Goddard Space Flight Center


Satellite Movie Shows Hurricane Iselle and Julio Moving Toward Hawaii [image-95]


[image-79]Aug.06, 2014 - NASA Satellite Paints a Triple Hurricane Pacific Panorama

In three passes over the Central and Eastern Pacific Ocean, NASA's Terra satellite took pictures of the three current tropical cyclones, painting a Pacific Tropical Panorama. Terra observed Hurricane Genevieve, Hurricane Iselle and Hurricane Julio in order from west to east. Iselle has now triggered a tropical storm watch in Hawaii.

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument is a key instrument aboard NASA's Terra and Aqua satellites. Between the two satellites, MODIS instruments view the entire surface of the Earth every one to two days. When NASA's Terra passed over the Central and Eastern Pacific in three swaths (or orbits), it captured images of each storm.

On Aug. 5, at 22:05 UTC (6:55 p.m. EDT) NASA's Terra satellite passed over Hurricane Genevieve and Hurricane Iselle in the Central Pacific Ocean, and Hurricane Julio in the  Eastern Pacific Ocean.

Genevieve Revived and Strengthens into a Hurricane

Satellite data shows that the structure of Genevieve has improved rapidly into a hurricane. At 1500 UTC (11 a.m. EDT), the center of Tropical Storm Genevieve was located near latitude 12.8 north and longitude 176.8 west. That puts the center of Genevieve about 1,065 miles (1,710 km) south of Midway Island and about 555 miles (895 km) west-southwest of Johnston Island. NOAA's Central Pacific Hurricane Center (CPHC) noted that Genevieve is moving toward the west-northwest near 17 mph (28 kph) and this motion is expected to continue through Thursday. Maximum sustained winds are near 75 mph (120 kph) and Genevieve is expected to become a typhoon in the west Pacific in the next day or two.

There are no coastal watches or warnings in effect.

Hurricane Iselle Triggers Watches in Hawaii

NOAA's CPHC issued a Tropical Storm Watch on August 6 at 1200 UTC (8 a.m. EDT) for Hawaii and Maui Counties in Hawaii. A tropical storm watch means that tropical storm conditions are possible within the watch area within 48 hours.

At 8 a.m. EDT on August 6, Hurricane Iselle was centered near latitude 16.9 north and longitude 144.1 west, about 745 miles (1,200 km) east of Hilo, Hawaii. NHC forecasters noted that maximum sustained winds are near 90 mph (145 kph) and gradual weakening is forecast during the next day or two. Iselle is moving toward the west near 13 mph (20 kph) and is expected to continue in that general direction for the next day. The estimated minimum central pressure is 989 millibars.

CPHC expects the outer winds of Iselle may reach the easternmost Hawaiian Islands early Thursday afternoon. Heavy rains may bring flash floods and mudslides as Iselle approaches. CPHC noted that large and dangerous swells from Iselle are expected to reach the main Hawaiian Islands today, while winds of tropical storm strength are possible on the Big Island Thursday, August 7.

[image-112]Julio Now a Hurricane

At 5 a.m. EDT on August 6, Tropical Storm Julio strengthened into the fifth hurricane of the Eastern Pacific Ocean hurricane season. By 11 a.m. EDT it was centered near latitude 15.2 north and longitude 130.5 west, about 1,650 miles (2,655 km) east of Hilo, Hawaii. NHC forecasters noted that maximum sustained winds were near 75 mph (120 kph) and some strengthening is forecast during the next day or two. Julio is moving toward the west-northwest near 17 mph (28 kph) and is expected to continue in that general direction for the next two days. The estimated minimum central pressure is 989 millibars.

Infrared data from instruments such as the Atmospheric Infrared Sounder on NASA's Aqua satellite revealed a small burst of strong thunderstorms developed with cloud tops of -75C to -80C over Julio's the low-level center of circulation during the morning (of August 6). The created a central dense overcast in the center. In addition, passive microwave satellite imagery has been indicating a closed low-to mid-level eye feature, which indicates that the storm has strengthened.

A Very Slowly Developing System Behind Julio

Trailing to the southeast of Julio is another developing tropical low pressure area called System 98E.  System 98E is actually a trough (elongated area) of low pressure located several hundred miles south-southwest of Acapulco, Mexico. The low is producing disorganized shower and thunderstorms. System 98E is expected to move to the west then west-northwest over the next couple of days and the National Hurricane Center gives it a very low (10 percent) chance of developing into a tropical depression over that time.

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


[image-63]Aug. 05, 2014 - NASA Sees Tropical Storm Julio as Part of a Heated Eastern Pacific

The Eastern Pacific Ocean has been warm this springtime, and those warmer waters have contributed to the development of storms like Tropical Storm Julio and Hurricane Iselle.

"Ocean temperatures in the Eastern Tropical Pacific were heated up because of the strong Kelvin wave activity this spring. Although the initial excitement of an impending El Nino has quieted down, these warmer waters have caused an early and active hurricane season," said Bill Patzert, Climatologist at NASA's Jet Propulsion Laboratory in Pasadena, California.

"Kelvin waves" are massive ripples in sea level that travel across the Pacific from Australia to South America.  Forecasters are paying close attention because these waves could be a herald of El Niño.

"Today, two strong cyclonic systems, Iselle (a major category 4 hurricane) and weaker Julio have their sights set on the Hawaiian Islands," Patzert said. "Hawaii is on high alert. Hurricane impacts in the Hawaiian Islands are quite unusual. Since 1950, only five hurricanes have made land-fall in the Islands. The good news is that both Iselle and Julio should weaken as they enter cooler ocean waters."

On August 5, NOAA's GOES-West satellite captured an image of Tropical Storm Julio and developing System 98E located near southern Mexico's coast.

On August 5 at 11 a.m. EDT (1500 UTC) Tropical Storm Julio had maximum sustained winds near 60 mph (95 kph). The National Hurricane Center (NHC) expects Julio to become a hurricane tomorrow, Wednesday, August 6.

Julio was centered about 1,145 miles (1,845 km) west-southwest of the southern tip of Baja California, near latitude 14.0 north and longitude 124.7 west. Julio is moving toward the west near 13 mph (20 kph). NHC expects a general westward to west-northwestward motion to continue through Thursday.

To the east of Tropical Storm Julio is yet another developing area of low pressure. That area, designated as System 98E is located near 10.3 north latitude and 98.1 west longitude several hundred miles south of Acapulco, Mexico. It has a medium chance of developing into a tropical depression in the next two days.

For more information about Kelvin Waves and a developing El Nino, visit: http://science.nasa.gov/science-news/science-at-nasa/2014/19may_elnino/

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center


[image-51]Aug. 04, 2014 - Satellite View of a Hyperactive Eastern and Central Pacific Ocean

NASA and NOAA satellites have been supplying forecasters with data developing tropical cyclones in the Eastern and Central Pacific Ocean and over the last several days. There have been as many as five tropical systems at the same time. On Monday, August 4, there were three tropical systems stretching from west to east: Tropical Depression Genevieve in the Central Pacific, Hurricane Iselle and Tropical Storm Julio in the Eastern Pacific.

Tropical Depression Genevieve May Strengthen

On August 4, Tropical Depression Genevieve was located about 930 miles (1,495 km) southwest of Honolulu, Hawaii. Maximum sustained winds were still near 35 mph (55 kph). Genevieve was moving westward at about 16 mph (26 kph). NOAA's Central Pacific Hurricane Center forecasts gradual strengthening late on August 4 and 5, so Genevieve could once again reach tropical storm status.

To the east of Genevieve lies low pressure area known as System 93C. It is producing disorganized showers and thunderstorms. System 93C is located about 500 miles south of Hilo, Hawaii. This low pressure area is moving to the west at 15 mph and currently has a near zero percent chance of becoming a tropical depression over the next couple of days.

[image-36]Hawaii on Guard for Hurricane Iselle

Behind System 93C to the east, lies Hurricane Iselle, the current powerhouse of the Eastern Pacific.

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite captured a clear visible image of Hurricane Iselle in the eastern Pacific Ocean on August 3 at 6:05 p.m. EDT. The image revealed Iselle's somewhat cloud-covered eye with bands of thunderstorms wrapping into the center from the eastern quadrant. The image was created by The MODIS Rapid Response Team at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

On August 4 at 1500 UTC (11 a.m. EDT) Hurricane Iselle's maximum sustained winds had increased to near 140 mph (220 kph) Iselle is a category four hurricane on the Saffir-Simpson hurricane wind scale. The eye of Hurricane Iselle was located near latitude 16.2 north and longitude 136.5 west.  Iselle was moving toward the west near 10 mph (17 kph). The National Hurricane Center noted that gradual weakening is forecast during the next couple of days. The estimated minimum central pressure is 947 millibars.

The current forecast track from the National Hurricane Center takes a weaker Iselle through the entire chain of Hawaiian Islands from August 7 through August 9.

Newborn Tropical Storm Julio Chasing Iselle

Tropical Storm Julio was born around 11 p.m. EDT on Sunday, August 3, about 795 miles (1,280 km) southwest of the southern tip of Baja California, Mexico.

On August 4 at 1500 UTC (11 a.m. EDT), Julio's maximum sustained winds were near 45 mph (75 kph). The center of Tropical Storm Julio was near latitude 13.5 north and longitude 119.4 west. Julio is moving toward the west near 13 mph (20 kph) and is expected to continue in a west to west-northwestward direction over the next couple of days. The estimated minimum central pressure is 1004 millibars.

Strong northeasterly vertical wind shear is pushing the strongest thunderstorms in Julio to the western side of the storm. The National Hurricane Center noted that the wind shear is expected to continue to August 5 or 6, which will limit any intensification. NHC expects Julio to become a hurricane later this week.

Satellites from NASA and NOAA continue to provide visible, infrared, microwave data to forecasters. Beginning in August, NASA's Hurricane Severe Storms Sentinel or HS3 mission takes to the Atlantic using two unmanned Global Hawk aircraft to study the storms. For more information about NASA's HS3 mission, visit: www.nasa.gov/HS3.

Text credit:  Rob Gutro
NASA's Goddard Space Flight Center

GOES-West satellite captured this image of a very active Eastern and Central Pacific
NOAA's GOES-West satellite captured this image of a very active Eastern and Central Pacific, hosting three tropical cyclones (from left to right) Genevieve, Iselle and Julio.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-36]
GOES-West satellite captured an image of the Eastern Pacific's Tropical Storm Julio and developing System 98E.
On August 5, NOAA's GOES-West satellite captured an image of the Eastern Pacific's Tropical Storm Julio and developing System 98E.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-63]
Terra image of Hurricanes Genevieve, Iselle, and Julio
On Aug. 5, at 22:05 UTC (6:55 p.m. EDT) NASA's Terra satellite passed over Hurricane Genevieve (left), Hurricane Iselle (center), and Hurricane Julio (right) in the Central and Eastern Pacific Oceans.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-79]
Youtube Override: 
3cEVueQ45-U
This animation of NOAA's GOES-East satellite imagery from August 2 through 7 shows the movement of Hurricanes Iselle (left) and Julio (right) toward the Hawaiian Islands.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-95]
MODIS image of Iselle and Julio
On August 6 at 22:30 UTC (6:30 p.m. EDT) NASA's Aqua satellite passed over Hurricanes Iselle (right) and Julio (left) approaching Hawaii. This image was created using three satellite passes.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-109]
A red cross marks Fermi's position at the time it detected a TGF above Tropical Storm Julio on Aug. 4.
A red cross marks Fermi's position at the time it detected a TGF above Tropical Storm Julio on Aug. 4. Green dots show lightning locations from WWLLN data 10 minutes before and after the TGF (magenta). Background: A GOES 15 image of Julio taken 19 minutes before the flash.
Image Credit: 
Michael Briggs/UAH and WWLLN; image: NASA/NOAA GOES Project
Image Token: 
[image-125]
view of Julio with TRMM data
Image Credit: 
NASA/Hal Pierce, SSAI
Image Token: 
[image-1400]
Julio's approach to Hawaii
On August 8, 2014 at 22:20 UTC, NASA's Aqua satellite captured Julio's approach to the Hawaiian Islands.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-157]
MODIS image of Julio
NASA's Aqua satellite captured this image of Julio on August 9, 2014 at 23:05 UT.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-173]
GOES-West image of the storm trio
On August 10 at 13:30 UTC the GOES-West satellite captured this image of three storms. Iselle's remnants are seen having past Hawaii and Julio is seen above the islands to the northeast. In the far west, Halong can be seen as it threatens Japan.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-189]
Julio north of the Hawaiian Islands
This Terra satellite image shows Hurricane Julio just north of the Hawaiian Islands on August 10, 2014 at 20:40 UTC.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-205]
NASA's Terra satellite captured this visible image of Tropical Storm Julio far north of Hawaii.
NASA's Terra satellite captured this visible image of Tropical Storm Julio far north of Hawaii on August 11 at 21:25 UTC.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-221]
Tropical Storm Julio far north of Hawaii, while two developing tropical lows are southeast of the islands.
This GOES-West satellite image from August 13 at 1200 UTC (8 a.m. EDT) shows Tropical Storm Julio far north of Hawaii, while two developing tropical lows are southeast of the islands.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-237]
MODIS image of Julio
On August 13 at 21:10 UTC (5:10 p.m. EDT), the MODIS instrument aboard NASA's Terra satellite captured this visible image of Hurricane Julio moving through the Central Pacific Ocean.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-253]
Tropical Storm Julio
NOAA's GOES-West satellite captured this image of Julio as it trailed along behind the other systems.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-51]
NASA's Terra satellite passed over Hurricane Julio in the Central Pacific Ocean.
NASA's Terra satellite passed over Hurricane Julio in the Central Pacific Ocean.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-112]
Animated GIF Override: 
Animated view of Julio with TRMM data
Image Credit: 
NASA/Hal Pierce, SSAI
Image Token: 
[image-141]
view of Julio with TRMM data
Image Credit: 
NASA/Hal Pierce, SSAI
Image Token: 
[image-204]
view of Julio with TRMM data
Image Credit: 
NASA/Hal Pierce, SSAI
Image Token: 
[image-220]
The TRMM Satellite captured both Hurricane Iselle and Julio in one image on August 7.
The TRMM Satellite captured both Hurricane Iselle and Julio in one image on August 7.
Image Credit: 
NASA/SSAI, Hal Pierce
Image Token: 
[image-238]
This GOES-West satellite image from August 7 at 1800 UTC (2 p.m. EDT) shows Hurricane Iselle approaching Hawaii and Hurricane Julio behind to the east.
This GOES-West satellite image from August 7 at 1800 UTC (2 p.m. EDT) shows Hurricane Iselle approaching Hawaii and Hurricane Julio behind to the east.
Image Credit: 
NASA/NOAA GOES Project
Image Token: 
[image-254]
MODIS image of Julio
Hurricane Julio was captured by the Terra satellite on August 8 at 20:10 UTC.
Image Credit: 
NASA Goddard MODIS Rapid Response Team
Image Token: 
[image-270]
AIRS image of Julio
When NASA's Aqua satellite passed over Tropical Storm Julio on August 14 at 8:23 a.m. EDT, AIRS infrared data showed that cloud tops had warmed except for a small area of strong thunderstorms (blue).
Image Credit: 
NASA JPL, Ed Olsen
Image Token: 
[image-398]
Image Token: 
[image-339]
Page Last Updated: August 15th, 2014
Page Editor: Lynn Jenner