EPZ Meso Update 2050Z

Forecaster comments from EWP blog...

CI products were able to correctly depict a small hail producing t-storm about 1.5 hours ahead of time.  In the first image below, the UAH CI showed a 53 index (upper left) indicating significant cloud growth at 1732Z.

The next image below shows CIMSS CI of -7 to -8 K/15 min at 1745Z (lower left) which is typical of weak storms based on recent studies.

 

The next image below at 1901Z depicts the same storm, 1.5 hrs later when it first reaches 60 dbz in KEPZ comp reflectivity (upper right) and 77-80 DVIL (lower right).  At this point the storm is likely producing small hail.

 

Another point to take away from this case is that for this environment, it takes about an index of 50 to 60 UAH CI to produce strong storms.