1. Weather Briefing May 21, 2013 National Weather Service Detroit/Pontiac, MI http://www.weather.gov/dtx Email: w-dtx.webmaster@noaa.gov w-dtx.webmaster@noaa.gov

2. weather.gov/detroit Hazard Summary Slight Risk This Afternoon Through Tonight Severe Weather Outlook This Morning through Tonight Storms early this morning Additional rounds expected this afternoon and early this evening Damaging Wind Potential Is The Greatest Threat

3. weather.gov/detroit Severe Weather Threats Today 60 mph Or Greater Bowing Line Segments Expected Around 1” In Diameter Isolated Tornado Threat This Afternoon And Tonight Damaging Winds Large Hail Tornado

4. weather.gov/detroit Severe Weather Outlook Slight Risk Tomorrow – Far Southeast Categorical Severe Weather Outlook Wednesday, May 22 Severe Weather Probabilities

5. Weather Map For Today Highlights Event Summary Slight Chance Of Severe Weather This Morning Through Tonight Warm/Moist Unstable Air And Close Proximity To Frontal Boundary Will Trigger Storms Across Southeast Michigan

6. Highlights Slight Chance Of Severe Weather Late This Afternoon Through Tonight Warm/Moist Unstable Air And Close Proximity To Frontal Boundary Will Trigger Storms Across Southeast Michigan

7. Decision Support Briefing Highlights Event Summary Forecast for Today (12 hrs) Threat of Severe Weather Friday and into Saturday All of Southeast Michigan

8. Weather Map Tuesday Evening Highlights Better Chance of Severe Weather Due To Closer Position Of Frontal Boundary

9. Weather Map Wednesday Highlights Lingering Chance of Severe Weather across the southeast as Low exits the region

10. Storm System Has History Producing Severe Weather

11. Severe Weather Details This Afternoon Through Tuesday Night weather.gov/detroit What Thunderstorms over Northern Wisconsin and Upper Michigan this morning could impact north of I-96 this afternoon. Little Severe Threat through 4pm Additional storms developing north and moving south after 4pm. Greatest Threat: Damaging Winds Lesser Threat: Large Hail, Tornadoes Localized Flooding Also Possible When Severe Weather is Possible 12pm Wednesday through 8 am Thursday Threat Greatest between 4pm Wednesday and 1am Thursday Where All of Lower Michigan North of Interstate 96 has Best Chance for Severe Weather North of a line from Pentwater to St. John’s - Most Favorable for Isolated Tornado and Heavy Rainfall Forecast Confidence Storms may develop sooner in the afternoon Strongest storms may miss us all together to the south

12. Forecast Challenges And Text too www.weather.gov/detroit Insert image for water vapor, other satellite, Instability Questions, etc. as needed for each event.

13. weather.gov/detroit Hazards Summary Review This Afternoon Through Wednesday Multiple Rounds Of Showers And Thunderstorms Through Wednesday, Creating Forecast Timing Difficulties. Multiple Rounds Of Showers And Thunderstorms Through Wednesday, Creating Forecast Timing Difficulties. Isolated Tornado Threat, Damaging Winds And Large Hail Possible This Afternoon Through This Evening Isolated Tornado Threat, Damaging Winds And Large Hail Possible This Afternoon Through This Evening Storms this morning may have gusty winds, however severe threat will be minimal Storms this morning may have gusty winds, however severe threat will be minimal Additional Thunderstorms are expected on Wednesday, with the best threat for severe weather across the far southeast in the warm sector Additional Thunderstorms are expected on Wednesday, with the best threat for severe weather across the far southeast in the warm sector Thunderstorms Will Produce Locally Heavy Rainfall – But Preceding Dry Stretch Of Weather Will Help Mitigate Significant Flood Threat. Thunderstorms Will Produce Locally Heavy Rainfall – But Preceding Dry Stretch Of Weather Will Help Mitigate Significant Flood Threat.

15. Additional Information NWS Detroit/Pontiac, MI http://www.weather.gov/dtx Email: w-dtx.webmaster@noaa.gov w-dtx.webmaster@noaa.gov Local Hazards Page http://www.weather.gov/detroit/svr.php Storm Prediction Center http://www.spc.noaa.gov