Department of Commerce ● National Oceanic & Atmospheric Administration ● National Weather Service NATIONAL WEATHER SERVICE INSTRUCTION 10-511 APRIL 15, 2020 Operations and Services Public Weather Services, NWSPD 10-5 WFO SEVERE WEATHER PRODUCTS SPECIFICATION NOTICE: This publication is available at: http://www.nws.noaa.gov/directives/. OPR: W/AFS21 (G. Schoor) Certified by: W/AFS21 (M. Hawkins) Type of Issuance: Emergency SUMMARY OF REVISIONS: This directive supersedes NWSI 10-511, dated August 20, 2018. The following changes were made to this instruction: 1) Reverted language about the “LAT…LON” section (4.3.5) parameters in the Severe Weather Statement (SVS) to previous version. 2) Additional guidance in Section 2.2.2 for Severe Thunderstorm Warning (SVR) issuance in situations where there are convective storms with little or no lightning. 3) Added “Broadcast Media” to the default list included in the IBW “Source” bullet for SVR (Section 2.3.5), TOR (3.3.5), and SVS (4.3.5). 4) Additional guidance on the inclusion of qualifying severe reports into warning product messages for SVR (Section 2.3.5), TOR (3.3.5), and SVS (4.3.5) and an example in the Appendix (4c). Digitally signed by STERN.ANDRE STERN.ANDREW.D.13829 W.D.138292034 20348 Date: 2020.04.16 08:23:26 8 -04'00' 04/15/2020 Andrew D. Stern Date Director, Analyze, Forecast, and Support Office NWSI 10-511 APRIL 15, 2020 WFO Severe Weather Products Specification Table of Contents: Page 1. Introduction ............................................................................................................................... 4 2. Severe Thunderstorm Warning (SVR) ...................................................................................... 4 2.1 Mission Connection .......................................................................................................... 4 2.2 Issuance Guidelines .......................................................................................................... 4 2.2.1 Creation Software .................................................................................................. 4 2.2.2 Issuance Criteria .................................................................................................... 4 2.2.3 Issuance Time ........................................................................................................ 4 2.2.4 Valid Time ............................................................................................................. 4 2.2.5 Product Expiration Time ........................................................................................ 4 2.3 Technical Description ....................................................................................................... 4 2.3.1 UGC Type .............................................................................................................. 4 2.3.2 MND Broadcast Line ............................................................................................. 4 2.3.3 MND Header ......................................................................................................... 4 2.3.4 Content ................................................................................................................... 5 2.3.5 Format .................................................................................................................... 6 2.4 Updates, Amendments and Corrections ......................................................................... 10 3. Tornado Warning (TOR) ........................................................................................................ 11 3.1 Mission Connection ........................................................................................................ 11 3.2 Issuance Guidelines ........................................................................................................ 11 3.2.1 Creation Software ................................................................................................ 11 3.2.2 Issuance Criteria .................................................................................................. 11 3.2.3 Issuance Time ...................................................................................................... 11 3.2.4 Valid Time ........................................................................................................... 11 3.2.5 Product Expiration Time ...................................................................................... 11 3.3 Technical Description ..................................................................................................... 11 3.3.1 UGC Type ............................................................................................................ 11 3.3.2 MND Broadcast Line ........................................................................................... 11 3.3.3 MND Header ....................................................................................................... 11 3.3.4 Content ................................................................................................................. 11 3.3.4.1 Tornado Emergency ..................................................................................... 12 3.3.5 Format .................................................................................................................. 13 3.4 Updates, Amendments and Corrections ......................................................................... 16 4. Severe Weather Statement (SVS) ........................................................................................... 18 4.1 Mission Connection ........................................................................................................ 18 4.2 Issuance Guidelines ........................................................................................................ 18 4.2.1 Creation Software ................................................................................................ 18 4.2.2 Issuance Criteria .................................................................................................. 18 2 NWSI 10-511 APRIL 15, 2020 4.2.3 Issuance Time ...................................................................................................... 18 4.2.4 Valid Time ........................................................................................................... 18 4.2.5 Product Expiration Time ...................................................................................... 18 4.3 Technical Description ..................................................................................................... 18 4.3.1 UGC Type ............................................................................................................ 18 4.3.2 MND Broadcast Line ........................................................................................... 19 4.3.3 MND Header ....................................................................................................... 19 4.3.4 Content ................................................................................................................. 19 4.3.4.1 Tornado Emergency ..................................................................................... 20 4.3.5 Format .................................................................................................................. 20 4.3.5.1 Event Tracking Number ............................................................................... 22 4.4 Updates, Amendments and Corrections ......................................................................... 22 5. Watch County Notification Message (WCN) ......................................................................... 23 5.1 Mission Connection ........................................................................................................ 23 5.2 Issuance Guidelines ........................................................................................................ 23 5.2.1 Creation Software ................................................................................................ 23 5.2.2 Issuance Criteria .................................................................................................. 23 5.2.3 Issuance Time ...................................................................................................... 23 5.2.4 Valid Time ........................................................................................................... 23 5.2.5 Product Expiration Time ...................................................................................... 23 5.3 Technical Description ..................................................................................................... 23 5.3.1 MND Broadcast Line ........................................................................................... 23 5.3.2 MND Header ....................................................................................................... 23 5.3.3 Content ................................................................................................................. 23 5.3.4 Format .................................................................................................................. 25 5.3.4.1 Event Tracking Number ................................................................................ 26 5.4 Updates, Amendments and Corrections ......................................................................... 26 APPENDIX A Examples A-1 3 NWSI 10-511