AWIPS images of the GOES-12 visible channel + surface reports

The remnants of Hurricane Ike moved rapidly northeastward across the Ohio River Valley region on 14 September 2008. AWIPS images of the GOES-12 visible channel (above) with an overlay of METAR surface reports showed that a large number of locations reported very strong wind gusts just to the south of the cluster of convection that marked the core of Ike’s remnants. Winds gusted to 43 knots (49 mph) at Pahucah, Kentucky (KPAH) at 14 UTC, 49 knots (56 mph) at Evansville, Indiana (KEVV) at 16 UTC, 65 knots (75 mph) at Lousiville, Kentucky (KSDF) at 18 UTC, 64 knots (74 mph) at Cincinnati, Ohio (KCVG) at 20 UTC, and 57 knots (66 mph) at Port Columbus, Ohio (KCMH) at 21 UTC. The highest unofficial wind gust reported was 73 knots (84 mph) at West Chester, Ohio (NWS WIlmington, Ohio summary).

An animation of a mosaic of US radar reflectivity (105-MB QuickTime movie, courtesy of the UW-Madison Department of Atmospheric and Oceanic Sciences) allows one to follow the progression of the remnants of Ike after the hurricane made landfall along the Texas coast. A large swath of heavy rain resulted, with a maximum amount of 11.02 inches reported in La Porte County, Indiana. In addition, an unusual tropical-type tornado outbreak occurred on 13 September in southern Michigan — a total of 5 tornado touchdowns occurred, producing significant damage in Paw Paw and Plymouth.

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GOES-12 and GOES-13 10.7 µm IR images

Hurricane Ike (satellite montage) made landfall as a Category 2 storm during the early hours of 13 September 2008. The comparison of GOES-12 and GOES-13 10.7 µm IR images (above) is a good demonstration of the value of the larger batteries on-board the GOES-13 (and newer) satellites — these larger batteries allow the satellites to operate through the Spring and Fall season “eclipse” periods (when the satellite is in the Earth’s shadow, and the solar panels cannot generate the power necessary to operate the GOES imager and GOES sounder instrument packages). Note that a strong spiral band was in the process of intensifying and moving inland along the far northeastern Texas and far southwestern Louisiana coastlines  during the GOES-12 eclipse period — the evolution of this feature was easily followed using the GOES-13 imagery.

AWIPS images of the MODIS 11.0 µm IR channel

A sequence of AWIPS images of the 1-km resolution MODIS 11.0 µm IR channel data (above) showed better details of the cloud features than could be seen using the 4-km resolution GOES IR imagery above.

A closer view using an AWIPS image of the MODIS 3.7 µm shortwave IR channel (below) uses a color enhancement designed to highlight some of the warmer features in the eye region –  some eyewall mesovortex structure was indicated on radar reflectivity data around the time that the eye was approaching the coast.

AWIPS image of the MODIS 3.7 µm IR channel + surface reports

Interestingly, the landfall of Hurricane Ike marked the first time on record that 6 consecutively-named tropical cyclones (Dolly, Edouard, Fay, Gustav, Hanna, Ike) have made landfall in the US.

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GOES-11 SRSO visible images

GOES-11 continued in Super Rapid Scan Operations (SRSO) mode on 11 September 2008, with visible imagery (above) showing additional convective bursts around the eye of the storm.

GOES-12 water vapor channel imagery (below) revealed an interesting series of middle- to upper-tropospheric “gravity waves” propagating radially outward away from Ike, moving inland over the Gulf Coast states.

GOES-12 water vapor images

A comparison of AWIPS MODIS images on 12 September 2008 (below) displayed Category 2 Hurricane Ike as the large storm approached the Texas coast. MODIS IR cloud top brightness temperatures at 16:58 UTC were as cold as -84º C (purple enhancement).

AWIPS images of the MODIS visible, IR, cirrus, and water vapor channels

An oblique view of a MODIS true color image using Google Earth (below; courtesy of Liam Gumley, CIMSS) shows that the clouds associated with Hurricane Ike covered a good deal of the Gulf of Mexico on 12 September.

MODIS true color image (viewed using Google Earth)

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GOES-11 SRSO visible images

The GOES-11 (GOES-West) satellite was placed into Super Rapid Scan Operations (SRSO) mode on 10 September 2008, allowing imagery at 1-minute intervals to monitor Hurricane Ike in the Gulf of Mexico. Using the visible channel imagery (above; QuickTime animation), the large satellite viewing angle from GOES-West positioned over the Pacific Ocean (the satellite zenith angle is approximately 66 degrees for features over the Gulf of Mexico) allowed for an interesting “oblique view” of convective bursts developing around the core of Hurricane Ike.

GOES-11 10.7 µm IR imagery (below; QuickTime animation) revealed a band of very cold cloud top temperatures — colder than -80º C (purple colors) — in the northeastern quadrant of Hurricane Ike early in the day. The minimum cloud top brightness temperature value of -83º C was seen at 12:49 and 13:19 UTC. During the course of the day, Hurricane Ike re-intensified into a Category 2 storm as it moved over a high Ocean Heat Content area in the eastern Gulf of Mexico.

GOES-11 SRSO IR images

A plot of NOAA aircraft reconnaissance data from the CIMSS Tropical Cyclones site (below) showed that Ike was a rather large hurricane, with tropical storm force winds extending  a significant distance away from the eye. TRMM/TMI (Tropical Rainfall Measuring Mission Microwave Imager) data indicated that Ike possessed a double eyewall structure, with a small inner eye within a very large outer eyewall.

GOES-12 IR image + NOAA aircraft reconnaissance data

A sequence of AWIPS images of the 1-km resolution MODIS 11.0 µm IR channel data (below) showed that Hurricane Ike remained very well organized even after its encounter with the island of Cuba.

AWIPS images of the MODIS 11.0 µm IR channel

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