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NWS Phoenix SKYWARN/Storm Spotter Program

South-Central & Southwest Arizona and far Southeast California (Map)

When significant, or severe weather occurs anywhere within the Phoenix County Warning Area, the Weather Service turns to the SkywarnTM Spotter Network to obtain timely and accurate reports. This network is comprised of individuals or groups, generally associated with the following: 1) Emergency Service Organizations (Fire, Police, etc), 2) Volunteer Organizations and 3) Weather enthusiasts.  Spotters should be at least 18 years of age though exceptions can be made on a case by case basis with pre-approval needed.   

Even with sophisticated technology like radar and satellites, there are a variety of atmospheric phenomena that require the human eye to detect and/or confirm.  This information is called "ground truth" and is provided by trained weather spotters throughout the year.  When hazardous weather occurs, Spotters provide detailed eye witness descriptions of the conditions to the local National Weather Service office by means of the Web, email, phone, or amateur radio.  Spotters in Southern Gila, La Paz, Maricopa, Northwest Pinal, Yuma, Imperial (CA), and Eastern Riverside (CA) counties should report to the Phoenix forecast office.  Click here for a map.

Spotters should provide the following information:

  • WHO they are (Spotter ID)
  • WHAT they saw or are seeing,
  • WHERE they are or where they were when it was going on.
  • WHEN the reportable conditions were first observed.

Reporting Criteria

The following criteria are what spotters should report to the National Weather Service - Phoenix. 

  • Tornado (on the ground)
  • Funnel Cloud (tail NOT touching the ground)        
  • Storm Damage (deaths, injuries, broken tree limbs, shingles off roofs, etc.)
  • Flooding (streets, running washes, etc.)
  • Low Visibility (less than 1 mile due to dust, sand, fog, etc. - except rain)
  • Rotating Wall Cloud
  • Heavy Rainfall (measured ½ inch or more accumulation in 30 minutes or less)
  • Hail  (diameter of largest stone - any size)
  • Structure fire caused by lightning (not tree fires).
  • Snow (accumulating or not)

Reporting Methods

Trained Spotters should utilize the methods outlined in the class (webpage, email, phone, radio).  For those who are not trained Spotters, you can send us a Tweet or post to our Facebook page. 




To become a Skywarn Spotter for the NWS Phoenix office requires full attendance of a free one hour webinar (and successfully completing a quick post-webinar quiz) or attending an in-person training class. Typically, the training sessions occur during the April through June time frame.  Refresher training is required once every two years (i.e. every other year).

The classes teach people how to properly identify and report significant weather phenomena and thereby contribute to public safety.  You will learn about how thunderstorms work, how to identify cloud features associated with microbursts and tornadoes, and how your reports tie in to warnings and advisories issued by the National Weather Service (NWS).  In addition, you will learn about all of the services available from the NWS.  The training is intended for residents of our forecast area (County Warning Area - CWA).  If you live outside of the area, you can use this map to locate the office that serves your location. 

Adult SKYWARNTM volunteers are community minded individuals who understand that they play a role in public safety by providing storm information to the National Weather Service.

If you have any questions, please contact Austin Jamison at 602-275-7418 at the NWS Phoenix Forecast Office. 

*** We especially need new spotters in more rural areas of our forecast area (County Warning Area - CWA)***


Training Class Schedule 


Open to residents of our forecast area (Map)


Date Time Location Registration Notes

April 17th


City of Maricopa

Standard class (in-person)

May 6th

6pm - 7pm


Standard class (Webinar)

May 20th

6pm - 7pm


Standard class (Webinar)

May 29th

6pm - 7pm

City of Avondale

Standard class (in-person)

June 5th

6pm - 7pm


Standard class (Webinar)

June 13th

6pm - 7pm

City of Yuma

Standard class (in-person)















Amateur Radio ("HAM" radio)

When a Skywarn Net has been activated for public safety purposes, trained Spotters who are amateur radio operators may submit storm reports by radio. There are also weekly routine Nets utilizing the same frequencies (see below).  These routine Nets are a good way to test how readily you can connect to those repeaters as well as practice interacting with a Net Controller.  


Maricopa and Pinal Counties - Sector 2 :

  • 443.050 MHz (PL Tone 100.0)  --  The first Wednesday of the month at 8 pm

Southern Gila County - Sector 6 (can be reached in portions of East Valley)

  • 147.200 MHz  (PL Tone 162.2)  --  Tuesdays at 8 pm

Yuma County - Sector 7:

  • 146.780 MHz (PL Tone 103.5)  -- Tuesdays at 7 pm

Imperial County - Sector 8 ***NEW***

  • 146.670 MHz (PL Tone 103.5) -- Tuesdays at 7pm

La Paz County and Blythe - Sector 9 

  • 145.310 (PL 107.2) and 147.06 (PL 203.5) - Wednesdays 7pm


Educational Resources


June 2024 Storm Spotter Newsletter (pdf 5.9 Mb)


February 2024 Storm Spotter Newsletter (pdf 9.0Mb)


September 2023 Storm Spotter Newsletter (pdf 5.4 Mb)


April/May 2023 Storm Spotter Newsletter (pdf 3.2 Mb)


January-February Storm Spotter Newsletter (pdf 4.0 Mb)


Study Guide for Standard Class (pdf 336KB)


PDF Version of Standard Class presentation (pdf 9.4 Mb)


***New*** Video Recording of the Advanced Storm Spotter webinar


PDF Version of Advanced Class presentation (pdf 17 Mb)


Spotter's Guide (pdf 27.2 MB):


JetStream - an Online School for Weather


Severe Weather 101 (educational content from NSSL)


MetEd (hundreds of online tutorials for the GeoScience community)


Radar Basics (pdf 7MB)


Radar Tutorials from NWS

  • Introduction to the WSR-88D system
  • Principles of Radar
  • Velocity Interpretation
  • Base and Derived Products
  • Convective Storm Structure and Evolution
  • Flash Floods
  • Winter Applications


NWS Norman Spotter Resources (emphasis on Great Plains severe weather)

  • Training Videos (informational - not a substitute for NWS Phoenix classes)


Severe Thunderstorm Forecasting (video lecture series by SPC forecasters)


NSSL’s HotSeat Warning Simulator





Additional Useful Links


CoCoRaHS - Citizen Scientists Reporting Daily Precipitation 


Rainfall Data Sources


NWS Publications and Brochures 


Climate Sites


Drought Sites