102  
ACUS11 KWNS 131804  
SWOMCD  
SPC MCD 131804  
COZ000-NMZ000-UTZ000-AZZ000-132000-  
 
MESOSCALE DISCUSSION 2070  
NWS STORM PREDICTION CENTER NORMAN OK  
0104 PM CDT SAT SEP 13 2025  
 
AREAS AFFECTED...EASTERN UTAH...WESTERN COLORADO...EXTREME NORTHEAST  
ARIZONA...AND FAR NORTHWEST NEW MEXICO  
 
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY  
 
VALID 131804Z - 132000Z  
 
PROBABILITY OF WATCH ISSUANCE...20 PERCENT  
 
SUMMARY...THUNDERSTORMS WILL CONTINUE TO INCREASE IN COVERAGE AND  
INTENSITY THROUGH THE AFTERNOON. THE STRONGEST STORMS WILL BE  
CAPABLE OF PRODUCING SMALL HAIL AND GUSTY THUNDERSTORM OUTFLOWS. A  
WATCH IS CURRENTLY NOT EXPECTED.  
 
DISCUSSION...THUNDERSTORMS WILL CONTINUE TO DEVELOP THROUGH THE  
AFTERNOON ACROSS THE REGION IN RESPONSE TO LARGE-SCALE ASCENT  
ASSOCIATED WITH A SEASONALLY STRONG TROUGH MOVING ACROSS THE  
INTERMOUNTAIN WEST. MODEST DIURNAL HEATING WILL CONTRIBUTE TO  
TEMPERATURES WARMING INTO THE LOW 70FS ACROSS THE REGION BENEATH  
COOL MID-LEVELS. THE RESULT WILL BE LOW-TO-MID-LEVEL LAPSE RATES ON  
THE ORDER OF 7-8.5 C/KM. THESE LAPSE RATES AND THE PRESENCE OF UPPER  
40FS TO LOW 50FS DEWPOINTS ACROSS THE AREA, WILL YIELD MOST UNSTABLE  
CAPE VALUES ON THE ORDER OF 1000, TO PERHAPS 1500, J/KG.  
 
EFFECTIVE-LAYER SHEAR INCREASES FROM NORTH TO SOUTH AS YOU GET  
CLOSER TO THE EMBEDDED SPEED MAX NEAR THE BASAL REGION OF THE  
TROUGH. HOWEVER, THE COLDER MID-LEVEL TEMPERATURES WILL BE DISPLACED  
A BIT FARTHER NORTH. DESPITE THE BEST OF BOTH BEING A BIT OFFSET,  
SUFFICIENT OVERLAP WILL GIVE RISE TO AT LEAST A MARGINAL SEVERE HAIL  
AND WIND THREAT WITH THE STRONGEST STORMS.  
 
A WATCH IS CURRENTLY NOT EXPECTED, BUT TRENDS WILL CONTINUE TO BE  
MONITORED.  
 
..MARSH/GUYER.. 09/13/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...PUB...ABQ...GJT...FGZ...SLC...  
 
LAT...LON 36990948 37551001 39351080 39911048 40300920 40270673  
38770679 37310691 36630782 36230890 36990948  
 
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
 
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