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Storm-Based Warnings Training


NOAA’s National Weather Service (NWS) implemented Storm-Based Warnings (SBWs) on October 1, 2007. SBWs (also known as threat-based or polygon warnings) were designed to depict the specific meteorological or hydrometeorological threat areas for severe weather warnings. This includes all tornado, severe, flash flooding, and marine warnings. By focusing on the true threat area(s) and not being restricted to counties, SBWs improve NOAA’s NWS warning accuracy and quality by reducing areas in counties that are not directly impacted by the severe weather threat. Moreover, SBWs promote improved graphical warning displays, and in partnership with the private sector, support a wider warning distribution through digital dissemination devices such as laptop computers, cell phones, Personal Data Assistants (PDAs), and other digital devices. 

The SBW Training Team has designed a SBW Training Course that provides specific guidance on how to issue warnings in the SBW era. The course, which is composed of a series of nine asynchronous (i.e., recorded web modules) lessons using Articulate Presenter and Weather Event Simulator (WES) exercises, is targeted to warning staff at NWS Forecast Offices. This course should have been completed prior to SBW implementation on October 1, 2007. However, NWS warning forecasters who were hired after this date may want to complete the course, or other forecasters may want to retake some of the training as a refresher. The course covers most types of severe storms over land or adjacent coastal waters and focuses on recognizing threat areas, polygon creation strategies using WarnGen (i.e., the NWS warning generation and dissemination application), and communication of threat areas to users.

NOTE: Besides the learning objectives for this training, which are evaluated by taking the Final Course Test in the NWS Learning Center Learning Management System (LMS), there are also several performance objectives for this training that are available in PDF format (120 KB).

Note to NWS Staff:

To receive credit for completing the Storm-Based Warning Training, you must complete the course requirements through the NWS Learning Center! The links below are for reference only.

Course Completion Steps

  1. Students must complete ALL SBW Course lessons in the LMS.
  2. Students must pass the Final Course Test in the LMS
  3. Students must complete ANY 4 out of 7 WES SBW exercises (at least 2 Cases).
  4. Notify WDTD via E-mail address for Storm-Based Warning Helpwhen coursework is complete (certificate will be mailed)

Contents of Storm-Based Warning Course

The table below describes the contents of the SBW Course. It is recommended that students complete Lesson 1 first. Then, complete Lesson 2, before working through the WES exercises. There is another important element of the SBW training which involves WarnGen OB 8.1 changes (37.4 MB ZIP file). This training, provided by Shannon White of the Forecast Decision Training Branch, includes basic functionality for how to use WarnGen OB 8.1 for creating storm-based warnings.

Lesson Title



 Lesson 1:

6.27 MB ZIP File

  • Goals, rationale of Storm-Based Warnings
  • Benefits and limitations
  • Verification changes
  • Implementation

30 min

Lesson 2,
Objective P1:
Low Shear Pulse Storm Severe Warning

14.1 MB ZIP File

  • Anticipating pulse storm movement after initiation
  • Storm interrogation
  • Shaping the polygon

5 min

Lesson 2,
Objective S1: Squall Line Severe Thunderstorm

1.80 MB ZIP File

  • Threat assessment
  • Radar evolution
  • Drawing line polygons to convey damaging wind threat

4 min

Lesson 2,
Objective FF-1: Basin-based Flash Flood Warnings

6.19 MB ZIP File

  • Flash flood threat assessment
  • Warning duration
  • Map backgrounds
  • FFMP analysis
  • 2 ways to draw polygons based on basin configuration
  • Flash flood warning issues

18 min

Lesson 2,
Objective T1: Tornadic Supercells

2.89 MB ZIP File

  • Six examples of drawing warning polygons from various types of potentially tornadic supercells

10 min

Lesson 2,
Objective T2:
2 Tornado Warnings in Close Proximity

8.27 MB ZIP File

  • Near storm environment
  • Radar summary
  • Drawing the polygons

5 min

Lesson 2,
Objective T3: Squall Line Tornado Warning

1.69 MB ZIP File

  • Threat Assessment
  • Drawing the Polygons
  • What Happened

3 min

Lesson 2,
Objective T4: Warning Issuance with Merging Storms

1.99 MB ZIP File

  • When storms collide
  • Drawing the initial polygons
  • Drawing the merged storms’ polygons

4 min

Lesson 2,
Objective T5:
Warning Issuance with Training Storms

1.84 MB ZIP File

  • Multiple storms moving over the same area
  • Combining warnings with single threat area
  • Overlapping polygons

4 min


WDTD would like to thank the following people who provided assistance in developing the SBW training course:

  • Shannon White (Forecast Decision Training Branch)
  • John Ferree (NWS Severe Weather Program Leader)
  • Ken Cook (NWS Wichita)
  • Todd Lericos (WFO Caribou)
  • Joseph Rogash (WFO El Paso)
  • Gary Woodall (WFO Ft. Worth)
  • Richard Okulski (WFO Memphis)
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Warning Decision Training Division
120 David L. Boren Blvd.
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Page Author: WDTD Webmaster
Page last modified: April 3, 2015 10:05

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