MODIS 0.65 µm visible, 3.7 µm shortwave IR, and 11.0 µm IR images

Winds gusting in excess of 50 mph across parts of eastern Idaho on 05 September 2010 created a plume of blowing dust which could be seen on AWIPS images of the MODIS 0.65 µm visible channel, the MODIS 3.7 µm shortwave IR channel, and the MODIS 11.0 µm IR channel data (above). The blowing dust plume appeared as a slightly brighter, hazy-looking feature on the MODIS visible image, but showed up as a darker feature on the MODIS shortwave IR image due to solar reflection off the small dust particles. There were also no extremely hot pixels (yellow to orange color enhancement) seen at the point source of the plume, ruling out the likelihood that this was smoke from a fire. On the IR image, the dust plume was about 10-15º C colder (lighter gray enhancement) than the surrounding warm land surfaces.

The blowing dust plume was even more apparent on 250-meter resolution Terra and Aqua MODIS true color Red/Green/Blue (RGB) images from the SSEC MODIS Today site (above), displayed using Google Earth. The tan color of the dust plume made it easy to distinguish from the brighter white meteorological clouds in the area. This blowing dust restricted visibility to less than 1/3 of a mile along Interstate 15 near Hamer, Idaho (Local Storm Report).

Terra and Aqua MODIS true color RGB images (displayed using Google Earth)

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GOES-13 6.5 µm water vapor images (with surface fronts analyses)

AWIPS images of the GOES-13 6.5 µm water vapor channel data (above) showed Hurricane / Tropical Storm Earl as it moved inland across the Canadian Maritime provinces on 04 September – 05 September 2010. However, at the same time a large mid-latitude cyclone was intensifying over far western Quebec — and the water vapor imagery began to display what appeared to be a warm conveyor belt signature (below) that stretched northwestward across Quebec and over Hudson Bay. It was somewhat surprising to see such a warm conveyor belt signature develop so close to the proximity of the back edge of the cloud shield of Earl.

GOES-13 water vapor image (with surface front analysis)

The GFS40 model winds within the 315-325 K isentropic layer (below) indicated that there was a strong 60-knot jet moving across the region where the warm conveyor belt signature formed on the water vapor imagery.

GOES-13 water vapor image + GFS 315-325 K layer winds

A pair of 1-km resolution MODIS 6.7 µm water vapor images (below) showed greater detail of the structure of the warm conveyor belt signature as it was forming.

MODIS 6.7 µm water vapor images

A sequence of four 1-km resolution POES AVHRR 10.8 µm IR images (below) showed the banding structure that was forming within the conveyor belt feature.

AVHRR 10.8 µm IR images

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MODIS Sea Surface Temperature product + RTG_SST Hi-Res model analysis

The image comparison above shows “before” and “after” views of the axis of the Gulf Stream off the southeast coast of the US. The “before” view is the Sea Surface Temperatue (SST) analysis from the RTG_SST High Resolution model at 00:00 UTC on 02 September 2010 (before Hurricane Earl arrived) — the axis of the Gulf Stream can be taken to be the wide  ribbon of SST values of 84º F and warmer.

The “after” view is an AWIPS image of the 1-km resolution MODIS Sea Surface Temperature product at 16:03 UTC on 03 September 2010 (after Hurricane Earl had passed). One can see the effect that Hurricane Earl had on the axis of the Gulf Stream, with warm and cold eddies of water — the red colors on the MODIS image are SST values in the middle 80s F, while the blue colors are SST values in the upper 70s F.

Terra and Aqua MODIS true color Red/Green/Blue (RGB) images from the SSEC MODIS Today site (below) showed Hurricane Earl moving along the East Coast of the US on 03 September. Note the increased amount of sediment flowing off the coast of North Carolina and South Carolina, due to heavy rainfall and strong offshore winds.

Terra and Aqua MODIS true color RGB images (displayed using Google Earth)

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GOES-13 0.63 µm visible images

McIDAS images of GOES-13 0.63 µm visible channel data (above, also available as a QuickTime movie) showed some interesting details associated with Tropical Storm Fiona in the central Atlantic Ocean on 02 September 2010: a series of intense convective bursts just south of a partially-exposed low-level circulation center, and a large northward-moving “outflow boundary” arc cloud. The GOES-13 satellite had been placed into Rapid Scan Operations (RSO) model, allowing images as frequently as every 5-10 minutes.

AWIPS images of the MIMIC Total Precipitable Water (TPW) product (below) revealed that a significant plume of TPW was being drawn northward from Tropical Storm Fiona into the circulation of Hurricane Earl. Note to National Weather Service forecast offices: see this site for details on how the CIMSS MIMIC TPW product can be added to your local AWIPS workstations, via Unidata LDM subscription.

MIMIC Total Precipitable Water product

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