GOES-12 fog/stratus and low cloud base products + MODIS fog/stratus product

AWIPS images of the 4-km resolution GOES-12 fog/stratus and Low Cloud Base products and the 1-km resolution MODIS fog/stratus product (above) showed fingers of river valley fog that had formed over parts of southern Missouri and northern Arkansas at around 08 UTC (3am local time) on 17 September 2008. The soil was moist across that particular region due to heavy rainfall associated with the passage of the remnants of Hurricane Ike 3 days earlier, creating an environment favorable for the formation of radiation fog. Many of the fingers of river valley fog had formed in areas located between the METAR surface reporting stations, so there were not a lot of reports of fog across the region at that time.

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GOES-13 visible images

Blog reader Michael Lawson wrote:

Hi, I am a meteorologist working with Meridian Environmental Technology in Grand Forks, ND. A co-worker noticed a gravity wave feature in the visible over northern Indiana/northwest Ohio during the afternoon of September 15, 2008. Clouds moving into the feature would dissipate then reform once they propagated through the other side. Thought it would make an interesting topic!

Thanks for the tip, Michael. GOES-13 visible imagery (above) did indeed show the wave as it propagated northwestward (against the ambient flow) across northern Indiana/Ohio into southern Lower Michigan on 15 September 2008.

The dissipation of the stratocumulus cloud field with the passage of the wave might be explained by examining the rawinsonde data from Wilmington, Ohio (below) — note the presence of very dry air aloft, which could have been briefly mixed downward as the wave moved through (similar to what was seen with an apparent hydraulic jump over lower Michigan and southern Ontario on 08 May 2008).

Wilmington OH rawinsonde data

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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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