MODIS 6.7 µm water vapor image + GOES-13 6.5 µm water vapor image

AWIPS images of the 1-km resolution MODIS 6.7 µm water vapor channel and the 4-km resolution GOES-13 water vapor channel data on 09 September 2010 (above) is another great example that demonstrates how an improvement in spatial resolution leads to a dramatic improvement in the ability to detect the total areal coverage of mountain wave signatures on water vapor imagery.

Overlays of RUC model wind speeds (below) indicated that a 105-knot upper level jet was located over the region — these strong winds were interacting with the complex terrain of the Rocky Mountains to produce the widespread mountain waves.

MODIS water vapor image + RUC model wind speeds

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MODIS fog/stratus product + GOES-11 fog/stratus product

AWIPS images of the 1-km resolution MODIS fog/stratus product and the 4-km resolution GOES-11 fog/stratus product (above) revealed the presence of fog and stratus clouds that extended fairly far inland across much of southern California around 06 UTC on 08 September 2010 (11 pm local time on 07 September). The improvement in spatial resolution on the MODIS image allowed a more accurate assessment of the location of the stratus cloud edges, as well as the location of the cloud holes immediately offshore.

McIDAS images of the GOES-15 0.63 µm visible channel data (below) showed how persistent this deck of stratus clouds was during the daytime hours. In fact, these clouds held down temperatures such that the daily high temperature was only 68º F at Burbank (station identifier KBUR, located near the center of the images) — their normal high temperature for the date is 88º F, and they had a high temperature of 102º F just 4 days earlier.

GOES-15 0.63 µm visible channel images

10-km resolution GOES-11 sounder Cloud Top Height product images (below) showed that there was a high amount of variability in the heights of these stratus cloud tops (which was also evident in the appearance of the stratus cloud deck on the GOES-15 visible imagery above).

GOES-11 sounder Cloud Top Height product

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Tropical Storm Igor has formed in the far eastern Atlantic, just south of the Cape Verde Islands. GOES-12 imagery from today (above) shows a sheared system with persistent and abundant convection southwest of a low-level swirl of clouds. (That low-level swirl is most evident in the 1145 UTC image). Igor formed just north of a region of significant shear (shown here) and the shear may slow intensification of the storm.

Other environmental factors favor strengthening. For example, MIMIC total precipitable water (from this website) shows abundant moisture surrounding the developing storm. An analysis of the Saharan Air Layer shows little signal in the region of the storm. Igor’s forecast path is over warm water. Forecasts from the National Hurricane Center suggest slow strengthening as the system moves westward across the tropical Atlantic.

For more information on Igor, visit the CIMSS Tropical Weather Website and the National Hurricane Center Website.

(Added: Click here for views centered on Igor from GOES-12, GOES-13 and GOES-15, satellites over the Equator at 60 W, 75 W and 89 W, respectively)

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GOES-13 0.63 µm visible images

GOES-13 0.63 µm visible images (above) showed the large circulation of Tropical Storm Hermine as it moved inland across Texas during the day on 07 September 2010.

GOES-13 0.63 µm visible images

A closer view of the well-defined circulation of Hermine was available using GOES-13 0.63 µm visible images (above) and GOES-13 10.7 µm IR images (below) from the CIMSS Tropical Cyclones site.

GOES-13 10.7 µm IR images

AWIPS images of the 1-km resolution MODIS 0.65 µm visible channel and the MODIS 11.0 µm IR channel data (below) showed Tropical Storm Hermine at 17:16 UTC (12:16 pm local time). The IR image depicted widespread areas with cloud top brightness temperatures of -75 º C to -85º C (purple color enhancement) around both the center of the storm and also the intense convective rain bands to the east. Very heavy rainfall amounts of 10-13 inches resulted from in inland passage of Hermine.

MODIS 0.65 µm visible and 11.0 µm IR images

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