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National Weather Service

National Weather Service. SKYWARN 2010! Concepts of Spotting and Reporting Severe Storms. National Weather Service Amarillo Forecast Office “Serving the Texas & Oklahoma Panhandles”. Mission of the NWS.

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National Weather Service

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  1. National Weather Service SKYWARN 2010! Concepts of Spotting and Reporting Severe Storms National Weather Service Amarillo Forecast Office “Serving the Texas & Oklahoma Panhandles”

  2. Mission of the NWS " The National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the protection of life and property and the enhancement of the national economy.”

  3. NWS Offices • Issue all Local Forecasts and Warnings • Build and Maintain RelationshipsWith Local and State Governments • Provide Expert Advice to EmergencyManagers and Emergency Operations Centers • Solicit Customer Feedback on Products and Services • Conduct Community Awareness and Education Programs • Train Volunteer Observers and Storm Spotters

  4. Amarillo County Warning Area

  5. Skywarn SpottersWhy are they so critical? Question: If you are a fire fighter, when would you want to be notified about an ongoing fire?

  6. History • WWII – spotter networks to protect weapon depots from lightning and severe weather • Tinker AFB Tornado in 1949 – spotter reports lead to first Tornado Warning, allowed aircraft to be moved to safer location • 1955 – Udall, KS tornado killed 80 people and injured 273, The Weather Bureau began to formally utilize severe weather spotters • First spotter class: March 8, 1959 in Wellington, KS, 225 attendees • NWS formalizes Skywarn in1965 after the Palm Sunday outbreak as a part of the Natural Disaster Warning System (NADWARN)

  7. The Goal of the Spotter Program • To equip you (the spotter) with the tools necessary to accurately observe the weather • Spotters play an important role in warning operations • Hail reports • Wind reports • Damage reports • Tornado reports • Winter weather too • This information helps the NWS provide the MOST accurate warnings/watches, advisories and statements

  8. Diversity of Skywarn • Program Management • Managed by NWS • Most offices have good EM participation • Some offices have little or no EM participation • Managed by EM • EM deploys spotters • EM takes their reports & relays them to NWS

  9. The Role of the SKYWARN Spotter Net Control Operators Skywarn Spotters Radar BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE AMARILLO TX 746 PM CST SUN FEB 8 2009 THE NATIONAL WEATHER SERVICE IN AMARILLO HAS ISSUED A SEVERE THUNDERSTORM WARNING FOR... Skywarn Observations Satellite NWS Forecasters

  10. To Give You an Idea of What a Spotter Might Spot… • In an “average” year across the Texas and Oklahoma Panhandles • We Issue 33 Tornado Warnings • 20-21 tornados actually occur • Issue 219 Severe Thunderstorm Warnings • Issue 20 Flash Flood Warnings

  11. The Role of the SKYWARN Spotter SKYWARN Spotters Identify and Report: Tornadoes, Wall Clouds, and Funnel Clouds Hail – Any size Winds – 50 mph or stronger Flash Flooding Significant Thunderstorm Features Other Significant Weather – Winter Weather!!

  12. The Role of the SKYWARN Spotter Reports should include the following information: WHO is calling… WHEREthe storm is located… WHAT severe weather is occurring… WHEN the severe weather occurred… HOW long did the severe weather last…

  13. What Do We Expect FromA Spotter? • Stay Safe! • Report what YOU see and only what YOU see • Stay out of disaster areasunless part of an emergencyresponse team

  14. Why Are Spotters So Important? • Because Radar only gives us a piece of the puzzle • Looks high in the storm • Does not “see” tornados • Indicates hail, but NOTthe exact size • Sometimes only showsrotation AFTER a tornado has formed • In other words:

  15. What the Radar "Sees" VS. What the Spotter "Sees" Radar 0.5° Radar Beam Spotter

  16. Near Petrolia TX 4/30/04 Gene Moore The Bottom Line The ONLY way we know there is a tornado is IF a human tells us!!

  17. In Summary – We Would Like You To Report… • A Tornado(s) • Funnel Clouds • Hail of ANY Size (even peas) • Strong winds, especially if you receive any wind damage • Heavy rain that causes any flooding • Water on roads, bar ditches filling up • And winter weather too (more on that later)

  18. Spotter Safety

  19. Tim Mrshall Mobile Spotter Safety TipsBeing on the road… • Best to spot with a partner. • Know where the storm is and how its moving. • Watch for water on the road. • Obey traffic laws. • Watch out for the other guy. • Always start with a full tank of gas. • Keep a well-maintained vehicle.

  20. Now for some Definitions • A Severe Thunderstorm MUST produce at least one of the following: • Hail one inch in diameter (quarter size) or larger • Wind gusts of 58 mph or greater • A Tornado

  21. More Definitions… • DOWNBURST- An intense downdraft from a thunderstorm that produces damaging wind gusts of 58 mph or greater. • Microburst– small scale (<2.5 miles), short-lived (<5 mins) downburst • Macroburst– large scale (>2.5 miles), long-lived (>5 mins) downburst • Derecho – Large scale, long-lived family of downbursts, sometimes persisting hundreds of miles. • FUNNEL CLOUD - A rotating, funnel-shaped cloud extending from a thunderstorm or towering cumulus. Spotters should report a ‘tornado’ if the funnel is in contact with the ground. • TORNADO - A violently rotating column of air extending from a thunderstorm, in contact with the ground.

  22. Still More Definitions… • FLASH FLOOD WARNING - Short-term flood (typically within 6 hours of the cause) which poses a threat to life and property. Flash flooding includes major small stream or urban flooding, rapidly flowing water, and dam/levee failure. • SMALL STREAM/URBAN FLOOD ADVISORY - Flooding that does not meet the flash flood criteria and should not pose a significant threat to life or property. Examples would include minor urban or small stream flooding, and standing water in low spots during or after heavy rain.

  23. Tornado Definitions Landspout: A type of tornado which is not associated with a thunderstorms mesocyclone (they form when ground based rotation is pulled into the updraft base of a thunderstorm). Tornado: Is a violent, dangerous, rotating column of air which is in contact with both the surface of the earth and the base of a thunderstorm.

  24. Near Tornadoes Dust Devil: Form as a swirling updraft under sunny conditions during fair weather, rarely coming close to the intensity of a tornado. Gustnado: Form due to non-tornadic cyclonic features in the downdraft from the gust (outflow) front of a strong thunderstorm, especially one which has become outflow dominated.

  25. Spotter Hazard:Lightning • Threat with ALL storms!! • First strike may be the one that gets you • Stay inside your vehicle or indoors

  26. Mobile Spotter Safety TipsLightning • Be cautious open areas – avoid being the tallest object • Be careful parking on a hill or high spots • Don’t park too close to metal fences/power lines

  27. Spotter Hazard:Damaging Winds • Non Tornadic Winds (straight line winds) • Various threat areas around a storm • Damage same/worse than a tornado

  28. What Is A Severe Wind? • Officially – 58 MPH or greater • How can you tell the wind speed if you do not have an anemometer? • Damage!

  29. Estimating wind speed • 40 to 55 mph - Non severe...Trees swaying, rain coming down horizontally, twigs and small limbs break, loose lightweight objects (trash cans, lawn chairs) blown around.

  30. Estimating wind speed • 60 to 80 mph...medium to large tree limbs downed, sheds, barns and weak structures damaged, truck pushed off the highway.

  31. Estimating wind speed • 80 to 100 mph+...numerous large tree limbs downed, shallow rooted trees pushed over, buildings partially unroofed, farm buildings, weak structures severely damaged.

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