The Joint Typhoon Warning Center (JTWC) website has for more than a day been tracking invest number 91W, shown above. The feature is circled in yellow, meaning development is unlikely in the next 24 hours. What satellite data might be used to make that determination?MIMIC Total Precipitable water fields, for the 24 hours ending... Read More

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) include an overlay of GLM Flash Extent Density — and showed the distinct circulation of a middle-tropospheric closed low (400 hPa analysis) as it moved northeastward across Illinois and Indiana into southern Lower Michigan on 25 March 2023. Isolated clusters of brief lightning activity were... Read More

Tutuila, the large island of American Samoa, experienced very heavy rain early in the morning of 21 March 2023, especially over the western parts of the Island. (However, the raingauge at the Pago Pago airport, in central Tutuila, received only 0.15″ of rain!) The animation above shows the development of... Read More

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) revealed an increasing amount of ice coverage within the nearshore waters of southern Lake Michigan on 07 February 2021 — this was due to a recent influx of arctic air across the Upper Midwest and western Great Lakes.A sequence of VIIRS True Color RGB and... Read More