May 25 - July 30
Measured Severe Convective Wind Gust Climatology of Thunderstorms for the Contiguous United States, 2003-2009
Andrew Winters, Bryan Smith, and Corey Mead
What is already known:
- There are many inconsistencies and limitations to the SPC wind database.
- Many studies thus far have focused largely upon convective modes responsible for generating severe convective wind gusts or environmental characteristics in which these events occur.
- Public observers tend to grossly overestimate encountered wind speeds.
What this study adds:
- A measured severe convective wind gust database and climatology for the contiguous U.S. from 2003-2009.
- Through the consideration of solely measured wind gusts, this study is afforded the consistency of an automated sensor.
- Evidences shows clear benefits of a dense observing network, such as the Oklahoma Mesonet, in observing and documenting severe weather events.
Abstract:
A severe convective wind gust climatology spanning 2003-2009 for the contiguous United States is developed using measured Automated Surface Observing System (ASOS), Automated Weather Observing System (AWOS), and Oklahoma Mesonet wind observations. National Lightning Detection Network and Radar Mosaic/Level II data are used amongst other quality control checks to identify and remove erroneous observational data. The filtered observations are then time matched with a number of diagnostic mesoanalysis fields from the Storm Prediction Center (SPC) for assessment of the severe convective wind gust environments. These data are then binned based on season and geographic region in order to identify atmospheric regimes characteristic to different parts of the country. The filtered observations are compared to storm reports archived by the SPC. Finally, a relatively denser surface observing network in Oklahoma is utilized to determine how consistently severe convective wind gusts are recorded by differing networks (i.e. ASOS/AWOS and Oklahoma Mesonet).
This study characterizes and contextualizes observations associated with southeast weak shear environments and contiguous U.S. strong deep layer shear, higher CAPE atmospheric regimes. Additionally, results exemplify the usefulness and necessity of a dense observing system network and demonstrate that the highest frequency of measured wind gusts occur throughout the southern and central High Plains and in a corridor from South Dakota across the southern Great Lakes region.