AZ SKYWARN^TM STORM SPOTTER PROGRAM

( PHOTOS  /  CRITERIA   /  SKYWARN^TM TRAINING )

When significant, or severe weather occurs anywhere within the Phoenix County Warning Area, the Weather Service turns to the Skywarn^TM 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 (HAM Radio, Citizens' Band Radio, etc), 3) Individual Citizens, 4) Cooperative Observers.

Be sure to check out the National Skywarn^TM Homepage to get the national perspective.

The Arizona Skywarn^TM Net (ASN) welcomes trained spotters to check into our weekly nets on these repeaters:

• 146.740 mhz  --  each Tuesday at 8 pm

• 442.800 mhz  --  each Wednesday at 8 pm

Storm spotters are specially trained by NWS personnel to be able to recognize and report severe and unusual weather occurrences. When this occurs, they phone their reports into the NWS office having warning responsibility for their county. Spotters in Southern Gila, La Paz, Maricopa, Northwest Pinal, Yuma, Imperial CA and Eastern Riverside CA counties should contact the Phoenix forecast office. Spotters in Apache, Coconino, Navajo, Northern Gila and Yavapai counties should call the Flagstaff office. Spotters located in Southeast Pinal, Pima, Santa Cruz, Cochise, Graham and Greenlee counties should contact the Tucson office. Finally, spotters in Mohave county should call the Las Vegas Weather Service Office.

Spotters should tell personnel at the responsible office briefly WHAT they saw or are seeing, WHERE they are or where they were when it was going on, WHEN it was occurring and WHAT is/was it doing. They should also include their name, location and their assigned spotter ID number.

SEVERE WEATHER SPOTTING - DESERT SOUTHWEST STYLE

The following are examples of weather phenomena that commonly lead to or depict severe weather. In most cases, what is seen below occurs during the Monsoon, or the summer thunderstorm season which typically runs from July 4 through September 15.

	Downburst Hazards.   Downburst winds can exceed 100 mph and are capable of doing the same damage as a weak to strong tornado. Rapidly shifting wind direction and changes in visibility pose problems to mobile spotters. (Photo by Alan Moller)
	Overshooting Top.   An overshooting top, an indicator of a potential severe thunderstorm, is evident as the "bubble" of cloud material rising above the rest of the storm. The area underneath the overshooting top is the area of strongest updraft, and is the preferred area for severe weather formation. (Photo courtesy of Bill Martin)
	Haboob.  A haboob is a violent dust or sandstorm occurring on the southwest deserts of Arizona. It depicts the leading edge, or gust front, of an approaching storm, and wind speeds can exceed 60 mph!

Although tornadoes are rare during the Monsoon, they can and do occur. There is a misconception that highway underpasses are a safe shelter for those caught in the path of a tornado. This is not the case! The following presentation "Highway Underpasses as Tornado Shelters" explains why this is so - this is an excellent presentation. Check it out!

CRITERIA

The following criteria are what spotters should look for when phoning in their reports. They should always call the responsible Weather Service Office when any of the below are noted:

1. TORNADO (on the ground) or FUNNEL CLOUD (tail not touching the ground)

2. ROTATING WALL CLOUD

3. WIND (estimated or measured at 40 mph or more)

4. MICROBURST (visually identified)

5. RAINFALL (1/2 inch (.50) or more in 30 minutes)

6. FLOODING (of any kind)

7. DAMAGE and/or DEATHS and/or INJURIES due to the weather event

8. HAIL (1/2 inch (.50) diameter, or greater)

9. VISIBILITY (less than 1/4 mile due to fog, dust, blowing snow or ash)

10. SNOWFALL (accumulating at a rate of 1 inch or more per hour.

SPOTTERS SHOULD NOT CALL NWS PERSONNEL WITH ROUTINE WEATHER OR FOR FORECASTS!!

TRAINING

Adult SKYWARN^TM volunteers are community spirited individuals, who understand that they play an essential role in providing storm information to the National Weather Service. Spotters are also hikers, sports and outdoor enthusiasts, and those who routinely work outdoors. Many volunteer spotters are amateur radio operators and participate in a special amateur radio network during severe weather.

If you have any questions, please contact either Steve Sipple or Ken Waters at 602.275.0073 at the NWS Phoenix Forecast Office. Please call during business hours only - 7 am to 330 pm M-F. They will be happy to answer them for you!

** We especially need new spotters in the remote areas of our County Warning Area (CWA), which includes Maricopa, northwest Pinal, and southern Gila counties!