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Dangerous Heat in the Western U.S.; Flash Flooding Possible Across Portions of the South

High temperatures in the 90s to 100s and warm overnight temperatures will continue across parts of the Interior Northwest, central California, and the Great Basin. Thunderstorms and heavy rain may produce scattered flash flooding across much of the Southern Rockies into the Southwest, particularly over sensitive burn scars in New Mexico, and across the Southeast into the Carolinas. Read More >

About Skywarn

SKYWARN, founded in the early 1970's is made up of a group of trained, dedicated amateur weather enthusiast who work in conjunction with the National Weather Service by observing and reporting adverse weather conditions to promote public safety and minimize property damage. In the advent of Doppler Radar, and other technologies, the art and science of weather forecasting has made great strides, but even with all the technology, the National Weather Service still is in need of 'ground truth' observers. It is through training that the NWS teaches interested volunteers to be safe, effective and accurate weather spotters who provide them with the needed ground truths.

SKYWARN, generally speaking, is placed on stand-by when a severe weather watch is posted by the National Weather Service. Once that watch is upgraded to a warning, SKYWARN becomes activated and spotters are asked to make severe weather observations. After making an observation that is reportable, there are several ways to relay the information to the National Weather Forecast Office which include: telephone, amateur radio, and an online storm report form. Some of the reports are used to send out statements, warnings and short-term forecasts to the public via the media. The reports also go into "Storm Data", which is a publication that documents severe weather across the country and can be used to create a severe weather climatology database of a specific county, city or region of the country.

Mammatus Snow

Reporting Severe Weather

Reporting severe weather is essential! Regardless of the reporting method, each report must include the time & location of the event (and direction looking if applicable). Pictures tell a thousand words, but not when and where the weather occurred! If you do send photos, please let us know if you grant permission for us to use them in future spotter talks and outreach presentations.

How to Report:

Email: - A great way to include pictures & video.

Online: -Able to use on a mobile device or home computer.

Telephone: NWS Missoula Severe Weather 800 Number - Must have been through severe weather spotter training and belong to a spotter network to use this line! Refer to materials received during spotter training.

Or call 406-329-4840

Facebook: Visit our Facebook page and post a severe weather report to our wall.

Twitter: Tweet us your reports by including the #idwx or #mtwx hashtag or send them directly to @NWSMissoula.

mPing: Send reports from your location via a smartphone app

Amateur Radio: The National Weather Service group amateur radio call-sign is WX7MSO.

What to Report:

With any report, please include your location (city or distance from city, street intersection, lat./lon.), the time of the event, and who you are (public, spotter #, law enforcement, etc.)



  • Distance & direction from your location
  • Movement (tornado direction & speed)
  • Impacts: Damage, injuries, or deaths
  • Tornado Behavior: Growing larger? Roping out?

Wall Clouds & Funnel Clouds

  • Wall cloud: Rotating? Persistent?
  • Funnel Cloud: How far to the ground
  • Visible rotation with the funnel?
  • Dust or debris below the funnel?
    (if so, you have a tornado!)


  • Diameter of the largest hailstone (estimated or measured)
  • DO NOT report marble-sized hail!! Marbles vary widely in size
  • Damage to windows, cars, crops, etc.
Hail Size Inches
 Pea 1/4
 Dime 1/2
 Penny 3/4
 Nickel 7/8
 Quarter 1
 Half Dollar 1 1/4
 Ping Pong Ball 1 1/2
 Golf Ball 1 3/4
 Hen Egg 2
 Tennis Ball 2 1/2
 Baseball 2 3/4
 Softball 4
 Grapefruit 4 1/2

Damaging Winds

  • Wind speed (estimated or measured)
  • Damage to trees, power lines, and structures
  • Trees: Diameter of limbs snapped off and health of tree (old or rotten?)
Designation Description
<1 Calm Smoke rises vertically
1-3 Light air Smoke drift indicates wind direction
4-7 Light breeze Weather vane moves, leaves rustle
8-12 Light breeze Leaves and twigs in constant motion
13-18 Mod breeze Dust raised, small branches move
19-24 Fresh breeze Small trees sway
25-31 Strong breeze Large branches move
32-38 Moderate gale Whole trees move, walking affected
39-46 Fresh gale Twigs break off trees, walking difficult
47-54 Strong gale Minor structural damage
55-63 Whole gale Large tree branches break
64-74 Storm  Widespread damage

Flash Flooding & Heavy Rain

  • Flood Impacts: Roads, houses, etc.
  • Depth of the water (estimated--use references such as cars or buildings)
  • Is the water moving swiftly or slowly?
  • Damage: Roads washed out, etc.
  • Rainfall amounts & how quickly it fell

Snow & Ice

  • Amount: (measured or estimated) Take multiple measurements and average them if possible.
  • Damage or impacts such as downed power lines, snapped tree limbs, cars off the road, etc.



Spotter Resources


The National Weather Service (NWS) hosts a combination of in-person and webinar-based spotter training classes across the Northern Rockies every year. For more information on these classes, please see the Spotter Training tab above.

In addition to live National Weather Service spotter training presentations, there are several online training opportunities available.

Online Resources

  • 2017 NWS Missoula Spotter Training Presentation (7 mb .pdf) - Note: Videos and animations will not play in this version of the talk.
  • Spotter's Field Guide (.pdf)
  • Spotter Card (.pdf)
  • COMET Skywarn Spotter TrainingThis course was developed by COMET, a program that supports, enhances, and stimulates learning about atmospheric and related sciences.

    The goal of the course is to provide baseline training for all spotters through multiple modules covering the procedures for spotting (including communication and spotter report criteria) and safety considerations for all hazards. There are two modules available including the Role of the SKYWARN Spotter and SKYWARN Spotter Convective Basics.  Students must register on the MetEd website to take the course.

    The following is in addition to registering as a SKYWARN Spotter at the end of the online course.

    To register as a spotter with the NWS in Missoula, please fill out this form: SPOTTER INFORMATION FORM
    Email to:
    Mail to: 6633 Aviation Way, Missoula, MT 59808

Other Training Resources

Public Reports Series

Why We Need Spotters


Winter Safety Tips

Lightning Safety


Compressed Spotter Training

2020 Spotter Training



Spotter Newsletter


Spring 2016 Fall 2016 Spring 2017 Fall 2017


Questions Call 406-329-4840