Severe Storm Hazards And Reporting
NOAA National Weather Service Green Bay www.weather.gov/grb NWSGreenBay NWSGreenBay Braydon Morisseau Building a Weather-Ready Wisconsin 1 Who IS the National Weather Service? The National Weather Service
The NWS is responsible for issuing forecasts and warnings for the protection of life and property We Need YOUR Help!
Locations of Automated Weather Instrumentation The NWS Depends on Weather Spotters to Fill in the Gaps It’s Technology and People Working Together to Save Lives Your TIMELY Reports are Essential! Why First Responders are Essential Weather Spotters
Are usually mobile Know areas and terrain well (can be precise with their location) Are trained in safety procedures Are always on duty and on watch
YOU can be a vital piece in the weather warning process!
• Hail over 1 inch AND/OR • Winds over 58 MPH AND/OR • Possible tornadoes AND/OR • If a tornado is spotted or rotation is seen on RADAR, a tornado warning is issued • A tornado warning may mean other severe thunderstorm hazards are present! • Heavy rain and possible flooding Watches vs. Warnings The NWS issues watches and warnings to allow you to take appropriate action to stay safe, but what does that mean?
: When to Report What to Report
The National Weather Service wants YOUR severe weather reports:
Tornado/waterspout Hail, ½” or larger Funnel cloud Any storm damage Rotating wall cloud Lightning that causes Flash flooding injury or damage Winds > 50 mph Tell us if measured or estimated Wind Damage Ways to Contact the NWS
Law enforcement or fire departments can make reports directly to NWS or through the county dispatch center (who then forward the report to the NWS) Thunderstorm “Straight-Line” Winds How to Report: Thunderstorm Wind Speeds
. People tend to over estimate wind speeds, so consider this if you are estimated winds . Avoid “heavy” or “strong” when describing wind . Measured wind speeds are a bonus!
30 - 40 mph Whole trees in motion
Twigs or small branches 40 - 50 mph breaking Slight structural damage; 50 - 60 mph Branches breaking Down or snapped trees; 60 - 70 mph Structural damage How to Report: Thunderstorm Wind Damage
What was damaged Character of the damage Extent of the damage Hail
Large hail is a result of strong or severe thunderstorms. About 35% of Wisconsin’s severe storms produce large hail. How to Report: Hail
Measure the hailstones at the = 4 inch hail longest width
Otherwise, use coins or other known objects to describe the size Avoid using “marble size” to describe hail
Report the size of LARGEST hailstone
Was there any damage? Tornadoes
A tornado is a rapidly rotating column of air in contact with the ground. Sometimes the visible funnel cloud does not reach the ground.
Nighttime Tornadoes
• Lightning can help • Transformers and power lines that are hit will flash • A roaring sound may be an indication of a tornado or high wind. How to Report: Tornadoes
– Wide? – Lifting or skipping? – Debris cloud? – Obscured by heavy rain? Tornado Look-Alikes: Things Might Not Be As They Seem A
LOOK FOR ROTATION! Tornado Look-Alikes
Rain Shafts and Hail Cores
Rain Shaft Hail Core
Look for rotation—if not rotating, then it’s not a tornado! Tornado Look-Alikes
Look for rotation—if not rotating, then it’s not a tornado! Flooding
ALL TYPES OF FLOODING POSE A THREAT! How to Report: Flooding How to Report: Other Thunderstorm Features
– Is it rotating? – How long has it existed
– Is it lowering? – Is it persistent? How to Report: Other Weather Types
Visibility ¼ mile or less
– Slick roadways – Any occurrence of freezing rain, ice accumulation and/or damage – Significant snowfall amounts – Blizzard conditions: winds 35 mph or more AND visibility ¼ mile or less When Reporting, Tell Us...
Who you are (Sheriff/Police/Fire…) Who the source of the report is Where it occurred (city/town and county) Please be as precise as possible with location What occurred When did it occur
Ways to Contact the NWS
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Law enforcement or fire departments can make reports directly to NWS or through the county dispatch center (who then forward the report to the NWS) THANK YOU!
We understand your dispatch and communications office is often busy during high-impact weather events.
Reports you forward to us are greatly appreciated and immediately used. Help Spread the Word!
Your organization can become a Weather-Ready Nation Ambassador
Promote WRN messages and themes Engage with NOAA on collaboration opportunities Share success stories of preparedness Serve as an example by educating employees on workplace preparedness
For more information: www.weather.gov/grb/weather-ready
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