Julio (Eastern Pacific) August 9, 2014


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.






























Aug. 08, 2014 - TRMM Satellite Views Hurricane Julio

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.













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.

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.

The TRMM Satellite captured both Hurricane Iselle and Julio in one image on August 7.









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.









Hurricane Julio was captured by the Terra satellite on August 8 at 20:10 UTC.











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


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.
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.

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.
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