National Weather Service United States Department of Commerce

Back-to-Back Pacific Storms to Impact the West Coast; Heavy Snow in the Central Appalachians

Back-to-back powerful Pacific storm systems to impact the Pacific Northwest and northern California through the end of this week with heavy rain, flooding, strong winds, and higher elevation mountain snow. A strong, long-duration atmospheric river will accompany the Pacific storms, bringing excessive rainfall and flash flooding to southwest Oregon and northwest California through the week. Read More >

First CG Lightning Convective Environment Browser


This study focused on the NWS Tampa Bay County Warning Area.

NOAA RAP model analysis data was used to partition events into nine NWS Tampa Bay flow regimes (below left) based on 1200 UTC mean vector wind in the red box on the below right image. These regimes were the same ones used to create the Florida Summer Thunderstorm Climatology web pages.

First Cloud-to-Ground (CG) and non-CG (null) events were identified for May-September (2012-2021) using USPLN lightning data between 1200 and 2359Z.

Composite soundings display the mean and 25th/75th percentile vertical temperature and dewpoint profiles and composite mean convective parameters for first CG events in each regime one hour before a first CG event and at 1800 UTC for non-CG (null) events.

Environmental parameter distributions use box-and-whisker plot approach for first CG events at -1 h and non-CG events at 1200 and 1800 UTC
 
Flow Regimes
Flow Regimes
Analysis Box
Regime Analysis Box

All images on this page can be magnified by clicking, and resized back to original size with a second click.