A Twelve Year Climatological Analysis of Severe Local Storms Observed by the Oklahoma Mesonet

Since 1994 the Oklahoma Mesonet has continuously measured surface conditions across the state with more than 100 remote, automated stations. Due to the relatively high frequency of severe weather in the state, the Mesonet has captured surface conditions associated with more than 300 significant severe weather events. In addition, the events observed consisted of various modes (i.e., supercells, squall lines, etc.) and types of severe weather (high winds, large hail, and tornadoes). The goal of this study is to understand the timing and duration of these past events and associated meteorological surface conditions prior to and during storm occurrence.

For this study, significant severe weather events were defined as any single convective day (1200 UTC – 1159 UTC) when (a) the total combined severe storm reports (hail and wind) was greater than or equal to 20 or (b) any tornado was reported in Oklahoma. The criteria were selected such that the full spectrum of storm modes was collected for the study period. As such, the main objectives of this study include: 1) quantify the occurrence of severe weather in Oklahoma from 1994-2005 using the Storm Prediction Center (SPC) storm report database, 2) identify storm mode, track, initiation points, and termination points using WSR-88D level II and III as well as Oklahoma Mesonet data, and 3) analyze critical surface features and conditions both prior to and during the occurrence of severe local storms using the Oklahoma Mesonet. Initial analyses and results will be presented.