482  
ACUS11 KWNS 202242  
SWOMCD  
SPC MCD 202242  
KSZ000-NEZ000-COZ000-210045-  
 
MESOSCALE DISCUSSION 1214  
NWS STORM PREDICTION CENTER NORMAN OK  
0542 PM CDT SAT JUN 20 2026  
 
AREAS AFFECTED...PORTIONS OF FAR EASTERN COLORADO...EXTREME  
SOUTHWESTERN NEBRASKA...AND WESTERN KANSAS  
 
CONCERNING...TORNADO AND SEVERE THUNDERSTORM WATCHES 357...358...  
 
VALID 202242Z - 210045Z  
 
THE SEVERE WEATHER THREAT FOR TORNADO AND SEVERE THUNDERSTORM  
WATCHES 357, 358 CONTINUES.  
 
SUMMARY...ALL SEVERE HAZARDS ARE POSSIBLE OVER THE NEXT COUPLE OF  
HOURS. HOWEVER, ONGOING STORMS SHOULD MERGE INTO AN MCS AND SUPPORT  
A POTENTIAL SEVERE WIND SWATH BETWEEN 00-04Z. A FEW GUSTS MAY REACH  
85-100 MPH.  
 
DISCUSSION...MULTIPLE HP SUPERCELLS, WITH A HISTORY OF HAIL 1-3  
INCHES IN DIAMETER, AND MEASURED GUSTS UP TO 90 MPH (89 MPH MEASURED  
BY NSSL MOBILE UNIT), ARE IN THE PROCESS OF GRADUALLY MERGING ALONG  
THE KS/NE BORDER, WITH A CONVECTIVE OUTFLOW BOUNDARY NOTED ACROSS  
CHEYENNE INTO RAWLINS COUNTIES. OVER THE NEXT COUPLE OF HOURS, THE  
MORE INTENSE AND DISCRETE UPDRAFTS WILL PERSIST WITH A SEVERE HAIL  
THREAT, WITH A FEW STONES EXCEEDING 2 INCHES IN DIAMETER. WHILE  
STORMS MAY BECOME OUTFLOW DOMINANT, AN ADDITIONAL TORNADO OR TWO MAY  
STILL OCCUR GIVEN THE AMOUNT OF LOW-LEVEL SHEAR CONCENTRATED ALONG  
THE WARM FRONT.  
 
OVER THE NEXT FEW HOURS, THE SUPERCELLS ARE EXPECTED TO MERGE INTO A  
COLD-POOL-DRIVEN MCS, WHICH WILL SURGE SOUTHWARD THIS EVENING. GIVEN  
PRECEDING 8-8.5 C/KM MID-LEVEL LAPSE RATES, AND A CORRIDOR OF 50-60  
KT BULK SHEAR VECTORS ORIENTED ROUGHLY NORMAL TO THE EXPECTED MCS  
LEADING-LINE ORIENTATION, THE MCS COULD BECOME HIGHLY ORGANIZED AND  
PRODUCE A SEVERE WIND SWATH. THIS SWATH WILL MOST LIKELY OCCUR  
SOMEWHERE IN THE 00-04Z PERIOD, CONTAINING ABUNDANT GUSTS IN THE  
60-70 MPH RANGE, WITH THE STRONGEST GUSTS POSSIBLY REACHING 85-100  
MPH, AS SUGGESTED BY SOME OF THE LATEST HRRR AND WOFS RUNS.  
 
..SQUITIERI.. 06/20/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...ICT...GID...DDC...GLD...PUB...BOU...  
 
LAT...LON 37100100 37220202 37360271 37460296 37660304 38750300  
39130299 39800287 40200216 40310147 40280061 40059973  
39779902 39229880 38349877 37749879 37329960 37150024  
37100100  
 
MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH  
MOST PROBABLE PEAK WIND GUST...85-100 MPH  
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN  
 
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