1 / 6

Tornado Warning Verification and its Relationship to Storm Type

Tornado Warning Verification and its Relationship to Storm Type. Eric Guillot July 12, 2007 REU Interim Presentation Mentors: Travis Smith Valliappa “Lak” Lakshmanan Greg Stumpf Don Burgess. Manual Storm Classification.

fhong
Télécharger la présentation

Tornado Warning Verification and its Relationship to Storm Type

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tornado Warning Verification and its Relationship to Storm Type Eric Guillot July 12, 2007 REU Interim Presentation Mentors: Travis Smith Valliappa “Lak” Lakshmanan Greg Stumpf Don Burgess

  2. Manual Storm Classification • Manually classified over 1,000 storms over three days worth of data (March 28th, May 5th, and May 28th of 2007). • Turned polygons into grids, overlaid with clustering program to decide which level of clustering performed the best

  3. Cluster Identification Using Kmeans • Radar base reflectivity analyzed by computer program to identify areas of concentrated reflectivity (clusters) • Lakshmanan, V., R. Rabin, and V. DeBrunner, 2003: Multiscale storm identification and forecast. J. Atm. Res., 67, 367-380 • Kmeans yields 3 different scales of clustering…we chose either C or D to train the decision tree • Mostly, cluster attributes at 420 km^2 (scale D) used for our study

  4. Decision Tree Training • Trained decision tree using manually classified storms in order to develop a logical process for automatically classifying them • Tested this decision tree on three additional cases (April 21st of 2007, and May 10th and 14th of 2006) • TSS=0.58; good enough for our study to continue

  5. Tornado Warning Verification • Tornado warnings from 45 different WFO’s overlaid with LSRs from SPC, coupled with closest storm at time of warning • Considered “hit” if warning matches up spatially and temporally with tornado report • Considered “miss” if no warning issued, but tornado reported • Considered “false alarm” if warning issued, but no tornado reported

  6. Preliminary Results • Breaking down forecast skill parameters by storm type yields insightful results • Seems to be most skill among forecasters for torndos spawned by isolated supercells • Forecasters seem to have most difficult time forecasting “landspouts” spawned in pulse storms and non-severe storms • Statistically prove that different storms spawn tornados that are easier/more difficult to forecast for

More Related