119  
ACUS11 KWNS 060045  
SWOMCD  
SPC MCD 060044  
NEZ000-COZ000-060245-  
 
MESOSCALE DISCUSSION 2247  
NWS STORM PREDICTION CENTER NORMAN OK  
0744 PM CDT SAT SEP 05 2026  
 
AREAS AFFECTED...PARTS OF WESTERN NEBRASKA INTO NORTHEASTERN  
COLORADO  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 659...  
 
VALID 060044Z - 060245Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 659  
CONTINUES.  
 
SUMMARY...THE RISK FOR LARGE HAIL MAY WANE OVER THE NEXT COUPLE OF  
HOURS, BUT STORMS MAY PERSIST AND EVOLVE INTO A SOUTHEASTWARD MOVING  
CLUSTER WITH POTENTIAL TO PRODUCE STRONG TO SEVERE WIND GUSTS WHILE  
APPROACHING THE NORTH PLATTE VICINITY THROUGH 8-10 PM MDT.  
 
DISCUSSION...STRONGEST CONVECTIVE DEVELOPMENT REMAINS FOCUSED  
NEAR/NORTH OF THE CHEYENNE RIDGE VICINITY OF THE NEBRASKA PANHANDLE.  
THIS IS OCCURRING BENEATH A FOCUSED DIFLUENT MID/UPPER FLOW REGIME,  
DOWNSTREAM OF LARGE-SCALE TROUGHING CENTERED NEAR THE PACIFIC COAST,  
AND JUST TO THE WEST OF THE AMPLIFIED GREAT PLAINS RIDGING.  
SOUTHEASTERLY LOW-LEVEL FLOW INTO THIS REGION HAS BEEN ENHANCING  
SHEAR (DUE TO PRONOUNCED VEERING WITH HEIGHT) ENOUGH TO SUPPORT A  
FEW EVOLVING SUPERCELL STRUCTURES OVER THE PAST SEVERAL HOURS.  
HOWEVER, SOUTHWESTERLY AMBIENT DEEP-LAYER MEAN FLOW IS QUITE WEAK,  
WITH SLOW STORM MOTIONS AND LITTLE MOVEMENT TO THE GENERAL AREA OF  
CONVECTIVE DEVELOPMENT.  
 
SURFACE OUTFLOW HAS BEGUN TO CONSOLIDATE INTO A STRENGTHENING  
SURFACE COLD POOL, WITH 2-4+ MB 2-HOURLY SURFACE PRESSURE RISES  
SAMPLED IN 00Z SURFACE OBSERVATIONS ACROSS THE SCOTTSBLUFF, ALLIANCE  
AND SIDNEY NE VICINITY. AS THIS ADVANCES SOUTHEASTWARD/SOUTHWARD,  
COINCIDENT WITH MODEST STRENGTHENING OF A SOUTHERLY LOW-LEVEL JET  
ACROSS THE HIGH PLAINS, IT IS POSSIBLE THAT LIFT ALONG/ABOVE THE  
OUTFLOW MAY SUPPORT AN UPSCALE GROWING CLUSTER OF STORMS THROUGH  
02-04Z. STRONGER CONVECTIVE DEVELOPMENT SEEMS MORE LIKELY TO  
PROPAGATE SOUTHEASTWARD TOWARD THE NORTH PLATTE VICINITY, THAN AREAS  
TO THE SOUTH, AIDED BY INFLOW OF MORE MOIST, POTENTIALLY UNSTABLE  
AIR.  
 
..KERR.. 09/06/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...LBF...BOU...CYS...  
 
LAT...LON 42120270 41950179 41440085 40690213 40740327 41390359  
41490350 42120270  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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