Storm Prediction Center Severe Thunderstorm Watch 239

Note: 
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for Watch Status Reports.

   SEL9

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 239
   NWS Storm Prediction Center Norman OK
   255 PM MDT Thu May 21 2026

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Northeast Colorado
     Nebraska Panhandle

   * Effective this Thursday afternoon and evening from 255 PM until
     1000 PM MDT.

   * Primary threats include...
     Scattered large hail and isolated very large hail events to 2
       inches in diameter possible
     Isolated damaging wind gusts to 70 mph possible
     A tornado or two possible

   SUMMARY...Thunderstorms will develop this afternoon and spread
   eastward across the watch area.  A few supercells are possible,
   posing a risk of large hail.  A tornado or two is possible by early
   evening as storms track into the eastern half of the watch.

   The severe thunderstorm watch area is approximately along and 50
   statute miles east and west of a line from 55 miles north northwest
   of Sidney NE to 50 miles southwest of Burlington CO. For a complete
   depiction of the watch see the associated watch outline update
   (WOUS64 KWNS WOU9).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 238...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 500. Mean storm motion vector
   28030.

   ...Hart

   SEL9

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 239
   NWS Storm Prediction Center Norman OK
   255 PM MDT Thu May 21 2026

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Northeast Colorado
     Nebraska Panhandle

   * Effective this Thursday afternoon and evening from 255 PM until
     1000 PM MDT.

   * Primary threats include...
     Scattered large hail and isolated very large hail events to 2
       inches in diameter possible
     Isolated damaging wind gusts to 70 mph possible
     A tornado or two possible

   SUMMARY...Thunderstorms will develop this afternoon and spread
   eastward across the watch area.  A few supercells are possible,
   posing a risk of large hail.  A tornado or two is possible by early
   evening as storms track into the eastern half of the watch.

   The severe thunderstorm watch area is approximately along and 50
   statute miles east and west of a line from 55 miles north northwest
   of Sidney NE to 50 miles southwest of Burlington CO. For a complete
   depiction of the watch see the associated watch outline update
   (WOUS64 KWNS WOU9).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 238...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 500. Mean storm motion vector
   28030.

   ...Hart

Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.

   SAW9 
   WW 239 SEVERE TSTM CO NE 212055Z - 220400Z
   AXIS..50 STATUTE MILES EAST AND WEST OF LINE..
   55NNW SNY/SIDNEY NE/ - 50SW ITR/BURLINGTON CO/
   ..AVIATION COORDS.. 45NM E/W /5SE BFF - 34NNW LAA/
   HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
   MAX TOPS TO 500. MEAN STORM MOTION VECTOR 28030.

   LAT...LON 41830242 38720201 38720386 41830436

   THIS IS AN APPROXIMATION TO THE WATCH AREA.  FOR A
   COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
   FOR WOU9.

Watch 239 Status Report Messages:

STATUS REPORT #2 ON WW 239

VALID 220030Z - 220140Z

SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 ESE CYS
TO 35 E SNY.

..KERR..05/22/26

ATTN...WFO...GLD...BOU...CYS...

&&

STATUS REPORT FOR WS 239 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

COC017-039-063-073-075-087-121-125-220140-

CO 
.    COLORADO COUNTIES INCLUDED ARE

CHEYENNE     ELBERT KIT CARSON     
LINCOLN      LOGAN MORGAN      
WASHINGTON     YUMA 
$$


THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY.  PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$

STATUS REPORT #1 ON WW 239

VALID 212325Z - 220040Z

THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.

..KERR..05/21/26

ATTN...WFO...GLD...BOU...CYS...

&&

STATUS REPORT FOR WS 239 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

COC017-039-063-073-075-087-121-125-220040-

CO 
.    COLORADO COUNTIES INCLUDED ARE

CHEYENNE     ELBERT KIT CARSON     
LINCOLN      LOGAN MORGAN      
WASHINGTON     YUMA 
$$


NEC007-033-105-123-220040-

NE 
.    NEBRASKA COUNTIES INCLUDED ARE

BANNER     CHEYENNE KIMBALL     
MORRILL      
$$


THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY.  PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$

Note:
 Click for Complete Product Text.

Tornadoes

Wind

Hail

Combined Severe Hail/Wind

For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The “Low” category contains probability values ranging from less than 2%
to 20% (EF2-EF5 tornadoes), less than 5% to 20% (all other probabilities),
“Moderate” from 30% to 60%, and “High” from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.