...Differences Between a Watch and Warning...
written by NWS Amarillo


A SEVERE THUNDERSTORM WATCH OR A TORNADO WATCH IS ISSUED WHEN 
ATMOSPHERIC CONDITIONS ARE FAVORABLE FOR THE DEVELOPMENT OF SEVERE 
WEATHER. 

SPECIFICALLY...

A SEVERE THUNDERSTORM WATCH IS ISSUED WHEN THE PRIMARY CONCERN IS FOR 
LARGE HAIL AND/OR DAMAGING THUNDERSTORM WINDS. PENNY SIZE OR LARGER 
HAIL IS CONSIDERED SEVERE AS IS THUNDERSTORM WIND GUSTS OF 58 MPH OR 
STRONGER. 

A TORNADO WATCH IS ISSUED WHEN SEVERE WEATHER IS EXPECTED WHICH ALSO 
INCLUDES THE LIKELIHOOD OF LARGE OR MULTIPLE TORNADOES. 

AFTER COORDINATING WITH AFFECTED NATIONAL WEATHER SERVICE FORECAST 
OFFICES...THE WATCH IS ISSUED BY THE STORM PREDICTION CENTER IN NORMAN 
OKLAHOMA. THE TYPICAL SIZE OF A WATCH AREA IS 25000 SQUARE MILES AND 
USUALLY TAKES THE SHAPE OF A 4 SIDED POLYGON. THE WATCH TYPICALLY 
LASTS FOR THREE TO SIX HOURS. WHEN A WATCH IS ISSUED... RESIDENTS AND 
OTHERS SHOULD BE ON THE ALERT FOR THREATENING WEATHER AND BE PREPARED 
TO MOVE QUICKLY TO SAFETY WHEN SEVERE WEATHER DEVELOPS. 

SEVERE THUNDERSTORM OR TORNADO WARNINGS ARE ISSUED BY LOCAL NATIONAL 
WEATHER SERVICE FORECAST OFFICES WHEN SEVERE THUNDERSTORMS OR 
TORNADOES ARE IMMINENT...EITHER AS INDICATED BY DOPPLER RADAR OR 
WHEN REPORTED BY RELIABLE SOURCES SUCH AS SKYWARN SPOTTERS. A WARNING 
USUALLY COVERS ONE COUNTY OR A PORTION OF A COUNTY AND NORMALLY LASTS 
FOR AN HOUR OR LESS. RESIDENTS AND OTHERS ARE URGED TO LISTEN CLOSELY 
TO THE INFORMATION CONTAINED IN THE WARNING AND SHOULD TAKE IMMEDIATE 
ACTION TO PROTECT THEMSELVES. DETAILS SUCH AS WHAT LOCATIONS ARE AT 
RISK AND PROTECTIVE MEASURES TO TAKE ARE ALWAYS MENTIONED IN THE 
WARNING.

REMEMBER...

IN A WATCH...WATCH THE SKY. IN A WARNING...TAKE ACTION.

FOR MORE INFORMATION ON SEVERE WEATHER TERMINOLOGY...CALL YOUR LOCAL 
NATIONAL WEATHER SERVICE OFFICE...OR VISIT THEM ON THE INTERNET AT 
http://www.srh.noaa.gov/.

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