Improving Weather Forecast Office Performance in the Polygon Warning Era Ken Cook – SOO ICT NOAA/National Weather Service Office 2142 South Tyler Road Wichita, KS Phone: (316) Fax: (316)

Ken Cook – SOO NWS Wichita, KS (ICT) Outline Polygon (Storm Based) Warnings FY08 Identify Challenges Ahead Demonstrate Training and Review Program (TARP) at WFO Wichita Software/Other Deficiencies Mitigations Developed from the TARP Results Recommendations/Conclusions Ken Cook – SOO NWS Wichita, KS (ICT)

Polygon-Based Tornado Warnings Improve Service Area Warned is Appropriately Reduced Four Counties Warned Polygon-Based Warning Area Area Removed From Warning In the current system, four full counties are warned. Polygon- Based Tornado Warnings provide much improved service. Source – Eli Jacks, National Program Management Committee

Ken Cook – SOO NWS Wichita, KS (ICT) Challenges Probability of Detection (POD) for Tornadoes percentage points less Nationwide (Polygons vs. Counties) Local POD of Severe Weather Events (1” Hail) about 15% points less No Comprehensive Training Plan available yet for implementation

Ken Cook – SOO NWS Wichita, KS (ICT) Challenges Lead Time Will Be Lost –Old: 3 separate warnings –New: One warning

Ken Cook – SOO NWS Wichita, KS (ICT) 24 April 2006

Ken Cook – SOO NWS Wichita, KS (ICT) 24 April ” Hail City of Wichita

Ken Cook – SOO NWS Wichita, KS (ICT) 24 April Million Dollars in Damage In Sedgwick County County-Based Paradigm, Warnings Verified Polygon-Based Paradigm, Largest Hail Not Warned (Bulk of the Damage Area)

Ken Cook – SOO NWS Wichita, KS (ICT) Challenges Local (ICT) POD of Severe Weather Events (1” Hail) –January through April: 15 % Points Less –May through August: Nearly Equal What changed?

Ken Cook – SOO NWS Wichita, KS (ICT) Training and Review Program A Training and Review Program Created –Identified shortfalls –Developed methods of improvement –Software Used: ArcGIS 9 Paint Shop Pro 9 Microsoft Access Presentation Software –Datasets Used: Storm Reports - Storm Prediction Center’s (SPC) web site Warning Polygon Shapefiles - Iowa State Mesonet web site

Ken Cook – SOO NWS Wichita, KS (ICT) Training and Review Program Findings –Reports that fell outside the warning polygon were the result of Boxology of warning (>90%) –Majority were gaps between warning polygons Software limitations Let’s Look at a Sample Review

Ken Cook – SOO NWS Wichita, KS (ICT)

Software Limitations LSR Program –Resolution not high enough WarnGen –Cannot incorporate detail of CWA boundaries Suggest working out a local agreement with local media and adjacent WFOs –Right clicking county to include in warning results in portions being excluded!! –Rounding of Warning Lat/Lon –Outdated/Poor Shapefile Resolution/Mapping EAS/NWR/etc… –Not using GPS

Ken Cook – SOO NWS Wichita, KS (ICT) Software Limitations LSR Program –Distance and direction resolution was too coarse –Result – wind report fell out of the polygon –Persons should examine these and make corrections as needed

Ken Cook – SOO NWS Wichita, KS (ICT) Software Limitations Poor Shapefile Resolution; Lat/Lon Rounding –WarnGen polygon coordinates when applied to the map background will appear slightly different

Ken Cook – SOO NWS Wichita, KS (ICT) Software Limitations EAS/NWR –Is this area warned or not? –Polygon - Yes –County - No –Even though we are shifting paradigms, public safety must be highest priority –Re-issue warning

Ken Cook – SOO NWS Wichita, KS (ICT) Mitigations Always be thinking ahead to the next box (1 st box very critical). Don't be too cute, leave yourself plenty of room. Avoid right clicking to include an entire county. Zoom and edit vertices appropriately. Zoom to examine new warnings in relation to the ones currently in effect to avoid gaps (it is a must to have local warnings overlay loaded w/ warngen). Slightly overlap polygons. This will eliminate gaps and any problems associated with mapping and lat/lon rounding. For Bow echoes, polygons that replicate the outline of the linear convection are best, as is “carpet bombing” for the large area of convection. When writing SVSs, in regards to readjusting a polygon for an SVS: Only readjust the polygon when a polygon includes more than one county and you wish to cancel one or more counties in the warned polygon.

Ken Cook – SOO NWS Wichita, KS (ICT) Mitigations Always be thinking ahead to the next box (1 st box very critical). Leave yourself plenty of room. Avoid right clicking to include an entire county. Zoom and edit vertices appropriately. Avoid gaps between polygons: Zoom!!! It is a must to have local warnings overlay loaded w/ warngen).

Ken Cook – SOO NWS Wichita, KS (ICT) Mitigations Slightly overlap polygons. For Bow echoes, replicate linear convection. Only adjust SVS Polygon when canceling portion of county.

Ken Cook – SOO NWS Wichita, KS (ICT) Results Polygonology has seen remarkable improvement at WFO ICT POD between the 2 paradigms within a few points FAR remains ~10 percentage points lower for Polygons

Ken Cook – SOO NWS Wichita, KS (ICT) Recommendations/Conclusions Developing a local training and review program will improve: –Transition to Polygon Warnings –Warning Meteorology and Service –Metrics (GPRA Goals) Utilize Mitigations Instructions for the ICT TARP are available upon request or on WFO ICT’s Science and Training Page at: Change is certain, be prepared!!!

Ken Cook – SOO NWS Wichita, KS (ICT) Recommendations/Conclusions Developing a local training and review program will improve: –Transition to Polygon Warnings –Warning Meteorology and Service –Metrics (GPRA Goals) Utilize Mitigations to improve polygon warnings Instructions for the ICT TARP are available upon request or on WFO ICT’s Science and Training Page at: Change is certain, be prepared!!! Thank you – Questions?

Ken Cook – SOO NWS Wichita, KS (ICT) Resources Cook, Kenneth (SOO – ICT), 2006: WFO Wichita Science and Training Intranet Page ( –Training Materials Also Available Herzmann, Daryl, 2006: Iowa State University ( National Program Management Committee SPC Storm Reports ( PANDA (