NWC REU 2002
May 12 - July 20



A Composite Study of Warm-Season Severe-Weather Episodes in the Florida Peninsula

Michael Hardiman, Pete Banacos, David Manning



Archived Storm Prediction Center (SPC) Outlooks and National Lightning Data Network (NLDN) cloud-to-ground lightning strike data over the Florida Peninsula for the warm season (April-September) 1994-2000 are examined to create a limited-scope climatological perspective of the nature of Florida Peninsula convection and SPC outlook skill during the warm season. Upper-air rawinsonde data is used to create composite soundings in numerous stratifications based on the nature of the daily surface features, deep-layer shear values, and months of the year in an attempt to find a thermodynamic or kinematic signal that delineates days with non-severe and severe convection.


Results show that SPC skill decreases during the months of June and July, as scattered thunderstorms in a weak shear environment develop on a near-daily basis over the Florida Peninsula.


Results of the composite rawinsondes indicate a distinct reoccurrence of a midlevel dry air layer on most large severe weather days in the peninsula. Other factors such as an increasingly steep 850-500 mb and 700-500 Mb lapse rate are also apparent on days exhibiting severe thunderstorms.


Case studies demonstrate the appearance of the aforementioned mid-level dry layer on many severe weather days, with a few outliers possibly indicating the existence of more than one typical profile for severe weather in the Florida Panhandle.

Paper available upon request.