Sep. 07, 2018 – Tropical Depression Gordon Still Lingering Over Arkansas
Tropical Depression Gordon just doesn’t want to give up. Gordon is meandering in the southern U.S. and satellites pinpointed its center over Arkansas on Friday, Sept. 7. Gordon continues to soak the southern U.S. and NASA’s Aqua satellite located the strongest storms associated with the depression.
NASA’s Aqua satellite provided an infrared look at clouds associated with Gordon and found its center over Arkansas. At 4:35 a.m. EDT (0835 UTC) on Sept. 7, the MODIS or Moderate Resolution Imaging Spectroradiometer instrument aboard NASA’s Aqua satellite looked at Tropical Depression Gordon in infrared light. AIRS found coldest cloud tops had temperatures near minus 63 degrees Fahrenheit (minus 53 degrees Celsius) around the center over southern Arkansas. NASA research has shown that storms with cloud tops that cold are high in the troposphere and can produce heavy rainfall.
On Sept. 7, the National Weather Service Weather Prediction Center noted that at 5 a.m. EDT (0900 UTC), Tropical Depression Gordon was located just 30 miles (45 km) south of Little Rock, Arkansas near latitude 34.5 degrees north and longitude 92.2 degrees west. The depression was moving toward the north near 5 mph (7 kph) and this motion is expected to continue today with a turn to the northeast Saturday, Sept. 8.
Maximum sustained winds are near 10 mph (20 kph) with higher gusts. A gradual increase in winds is expected as the low becomes extra-tropical over the weekend
The estimated minimum central pressure is 1013 millibars.
As with any tropical system over land, heavy rain and flooding is a main concern. Gordon is expected to produce total rain accumulations of 3 to 6 inches over Missouri into the Midwest, with possible isolated maximum amounts of 10 inches through Saturday night. This rainfall will likely cause local flooding and flash flooding.
For more information on rainfall totals please see the Storm Summary available at www.wpc.ncep.noaa.gov/discussions/nfdscc2.html
For updates on Gordon, visit: https://www.wpc.ncep.noaa.gov/tropical/tropstorms.shtml
By Rob Gutro
NASA’s Goddard Space Flight Center
Sep. 06, 2018 – Satellites Tracking the Rainfall from Tropical Depression Gordon
Gordon is still considered a tropical depression as it makes its way into the south central U.S. NOAA’s GOES-East satellite provided an infrared look at clouds associated with Gordon and found its center over Mississippi.
On Sept. 6, the National Weather Service noted that Flash Flood Watches are in effect over portions of Mississippi and Arkansas. The National Weather Service said that the threat of heavy rains and flooding will continue for several days.
At 5 a.m. EDT (0900 UTC), Tropical Depression Gordon was located near latitude 33.7 degrees north and longitude 91.3 degrees west. The center was located about 115 miles (185 km) north-northwest of Jackson, Mississippi.
The depression is moving toward the west-northwest near 8 mph (13 kph) and this motion is expected to continue today. Maximum sustained winds are near 25 mph (35 kph) with higher gusts. Little change in strength is forecast during the next 48 hours. The estimated minimum central pressure is 1015 millibars.
NOAA’s GOES-East satellite captured an infrared image of Gordon on Sept. 6 at 8 a.m. EDT (1200 UTC) as it continued to move toward Arkansas. The image showed clouds in an egg-shape near the center of circulation.
Gordon is expected to produce total rain accumulations of 3 to 7 inches over northwest Mississippi and much of Arkansas, up into the Midwest, with possible isolated maximum amounts of 10 inches through Saturday night. This rainfall will likely cause local flooding and flash flooding.
For more information on rainfall totals please see the Storm Summary available at www.wpc.ncep.noaa.gov/discussions/nfdscc2.html
For updates on Gordon, visit: www.nhc.noaa.gov
By Rob Gutro / Hal Pierce
NASA’s Goddard Space Flight Center
Sep. 05, 2018 – NASA Finds Strong Rain Potential in Tropical Storm Gordon
NASA’s Aqua satellite passed over the Gulf of Mexico and collected temperature information on Tropical Storm Gordon’s clouds as it moved toward landfall and after landfall. Those cloud top temperatures indicated that Gordon has the potential to generate heavy rainfall as it moves inland over the next several days.
The Atmospheric Infrared Sounder or AIRS instrument aboard NASA’s Aqua satellite passed over Tropical Storm Gordon on Sept. 4 at 3:05 p.m. EDT (19:05 UTC) and analyzed the storm in infrared light. Infrared light provides temperature data and that’s important when trying to understand how strong storms can be. The higher the cloud tops, the colder and the stronger they are.
When Aqua passed over Gordon, the AIRS instrument found coldest cloud top temperatures in thunderstorms. Those temperatures were as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius). Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.
Soon after the AIRS image, the National Hurricane Center or NHC noted “Gordon has been undergoing another convective bursting phase during the past few hours, with a sharp increase in Doppler velocity values noted between 9,000-12,000 feet (meaning cloud tops were reaching that altitude).”
At 11 a.m. EDT on Sept. 4, the NHC said that aircraft and radar imagery showed that the center of Gordon was making landfall just west of the Alabama-Mississippi border.
On Sept. 5 at 3:10 a.m. EDT (0710 UTC) Aqua passed over the Gulf coast again, and the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard measured infrared temperatures. That data showed the cloud top temperatures were as cold as they were when AIRS passed over 12 hours before. However, they were not in as wide an area. The coldest cloud tops and heavy rainmaking storms were around the low-level center and in a large band east of the center.
At 8 a.m. EDT (1200 UTC) on Sept. 5, the National Hurricane Center (NHC) noted the center of Tropical Depression Gordon was located near latitude 32.0 degrees north and longitude 89.9 degrees west. The center of circulations is about 25 miles (40 km) south-southeast of Jackson, Mississippi.
Gordon is moving toward the northwest near 14 mph (22 kph). A northwestward motion with some decrease in forward speed is expected over the next couple of days. A turn toward the north-northwest and north is forecast to occur on Friday. Maximum sustained winds have decreased to near 35 mph (55 kph) with higher gusts in a few squalls near the center. Additional weakening is expected as Gordon moves farther inland.
The NHC’s key messages are that heavy rainfall from Gordon will affect the western Florida Panhandle, southwest Alabama, southern and central Mississippi, northeastern Louisiana, Arkansas, Missouri, southern Iowa and Illinois, with isolated maximum amounts of 12 inches through early Saturday. This rainfall will cause flash flooding across portions of these areas.
On the forecast track, the center of Gordon will move across the lower Mississippi Valley today.
For updated forecasts on Gordon and local effects including storm surge, rainfall, wind and tornadoes, visit: www.nhc.noaa.gov.
By Rob Gutro
NASA’s Goddard Space Flight Center
Sep. 04, 2018 – NASA Finds Tropical Storm Gordon’s Strength East of Its Center
After drenching south Florida, Tropical Storm Gordon moved into the eastern Gulf of Mexico and is headed to the northwest. NASA’s Aqua satellite found three areas of the strongest storms east of Gordon’s center when it passed overhead on Sept. 4 .
Infrared satellite data on Tuesday, Sept. 4 at 4:05 a.m. EDT (0805 UTC) from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite revealed several strongest areas in Gordon where cloud top temperatures were indicative of strong storms and heavy rainmakers. In those areas, MODIS found coldest cloud tops had temperatures near minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius). NASA research has found that cloud top temperatures that cold have the capability to generate heavy rainfall.
At 5 a.m. EDT (0900 UTC), the National Hurricane Center or NHC noted “The storm has a small CDO [central dense overcast] with convective banding features primarily over the eastern semicircle of the circulation.” It is in the eastern semicircle where Aqua found the strongest storms.
There are numerous watches and warnings in effect as Gordon is forecast to track through the Gulf of Mexico and make landfall along the northern Gulf coast. NHC said A Storm Surge Warning is in effect for Shell Beach to Dauphin Island, Alabama. A Storm Surge Watch is in effect from west of Shell Beach to the Mouth of the Mississippi River and east of Dauphin Island to Navarre, Florida. A Hurricane Warning is in effect for. The mouth of the Pearl River to the Alabama-Florida Border. A Tropical Storm Warning is in effect for west of the mouth of the Pearl River to east of Morgan City, Louisiana, including Lake Pontchartrain and Lake Maurepas and from the Alabama-Florida Border to Okaloosa-Walton County Line, Florida..
At 8 a.m. EDT (1200 UTC), the center of Tropical Storm Gordon was located near latitude 28.1 degrees north and longitude 86.2 degrees west. That’s about 190 miles (305 km) east-southeast of the mouth of the Mississippi River. Gordon is moving toward the west-northwest near 15 mph (25 kph). A west-northwestward to northwestward motion with some decrease in forward speed is expected over the next few days.
NHC said that maximum sustained winds are near 65 mph (100 kph) with higher gusts. Some strengthening is expected today, and Gordon is forecast to be a hurricane when it makes landfall along the north-central Gulf Coast. Rapid weakening is expected after Gordon moves inland.
On the forecast track, the center of Gordon will move across the eastern Gulf of Mexico today, and will approach the north-central Gulf Coast within the warning area late this afternoon or evening, and move inland over the lower Mississippi Valley tonight or early Wednesday, Sept. 5.
For updates on Gordon, visit: www.nhc.noaa.gov
By Rob Gutro
NASA’s Goddard Space Flight Center
Sep. 03, 2018 – NASA Observes Formation of Tropical Storm Gordon in Upper Florida Keys
Infrared data from NASA’s Aqua satellite showed Tropical Storm Gordon formed over the Upper Florida Keys on Sept. 3.
At 3:20 a.m. EDT (0720 UTC) on Sept. 3, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite looked at newly formed Tropical Storm Gordon in infrared light. MODIS found coldest cloud tops had temperatures near minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius) south of the Florida Peninsula. Storms with cloud top temperatures that cold have the capability to produce heavy rainfall. Fragmented bands of thunderstorms extended over south Florida and into the Bahamas.
At 5 a.m. EDT, the National Hurricane Center noted Storm Surge Watch is in effect for the Mississippi-Alabama border westward to the Mouth of the Mississippi River. A Tropical Storm Warning is in effect for Golden Beach to Bonita Beach, Florida; from Craig Key to Ocean Reef, including Florida Bay, and for the Alabama-Florida border westward to east of Morgan City, Louisiana, including Lake Pontchartrain and Lake Maurepas. Heavy rainfall, storm surge and tropical-storm force winds are expected in the warning areas. For details: https://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/031227.shtml?
The National Hurricane Center noted at 8: 30 a.m. EDT (1230 UTC), the center of Tropical Storm Gordon was located by NOAA Doppler weather radar and surface observations near latitude 25.1 degrees north and longitude 80.7 degrees west.
Gordon is moving toward the west-northwest near 17 mph (28 kph) and a west-northwestward to northwestward motion is expected over the next 72 hours. On the forecast track, the center of Gordon will pass over the southern tip of the Florida peninsula this morning, move over the southeastern Gulf of Mexico this afternoon and evening, and reach the warning area along the central Gulf Coast by late Tuesday or Tuesday night.
Surface observations and radar data indicate that maximum sustained winds have increased to near 45 mph (75 kph) with higher gusts. Additional strengthening is forecast during the next 48 hours.
For updates on Gordon, visit: www.nhc.noaa.gov