316  
FXUS65 KCYS 210925  
AFDCYS  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHEYENNE WY  
325 AM MDT SAT JUN 21 2025  
   
KEY MESSAGES
 
 
- HOT TEMPERATURES WILL CONTINUE SATURDAY. NEAR RECORD HIGH  
TEMPERATURES ARE POSSIBLE.  
 
- COOLER TEMPERATURES EXPECTED FOR MOST OF NEXT WEEK AS A  
PACIFIC COLD FRONT MOVES ACROSS THE AREA LATE SUNDAY.  
 
- SHOWERS AND THUNDERSTORMS WILL RETURN TO THE AREA AS EARLY AS  
SUNDAY AFTERNOON, WITH MOST OF THE ACTIVITY EXPECTED LATE  
MONDAY THROUGH THURSDAY.  
 

 
   
SHORT TERM /THROUGH MONDAY/
 
 
ISSUED AT 310 AM MDT SAT JUN 21 2025  
 
CURRENT SURFACE OBSERVATIONS ACROSS THE AREA EARLY THIS MORNING  
SHOWS MILD TEMPERATURES AND GUSTY WINDS CONTINUING AS THE 500MB  
TO 700MB THERMAL RIDGE AXIS LIFTS NORTHEAST ACROSS THE PLAINS.  
TEMPERATURES AT 2 AM HAVE BEEN ON THE WARM SIDE, WITH READINGS  
IN THE 70S AND EVEN LOW 80S ACROSS SOUTHEAST WYOMING. CHEYENNE  
RECORDED A TEMPERATURES OF 80 AN HOUR AGO WITH GUSTY SOUTHWEST  
WINDS. THIS IS PRETTY ATYPICAL AROUND HERE LATE AT NIGHT, EVEN  
IN THE SUMMER. LIGHT WINDS FURTHER EAST HAVE RESULTED IN GOOD  
RADIATIONAL COOLING WITH READINGS AROUND 60 FOR THE WESTERN  
NEBRASKA PANHANDLE AND FAR EASTERN WYOMING. CANCELLED THE HIGH  
WIND WARNING FOR MOST OF SOUTHERN AND CENTRAL CARBON COUNTY WITH  
WINDS IN THESE AREAS GENERALLY UNDER 25 MPH. HOWEVER, KEPT THE  
HIGH WIND WARNING GOING FOR THE ARLINGTON/ELK MOUNTAIN AREA AND  
THE LARAMIE VALLEY SINCE GUSTS ARE STILL PEAKING AROUND 50 MPH  
LATE LAST NIGHT/EARLY THIS MORNING. WITH GOOD MIXING EXPECTED  
AROUND SUNRISE, DECIDED TO KEEP THIS WARNING GOING UNTIL 9 AM  
SINCE MODELS CONTINUE TO SHOW AN AREA OF 55 KNOT WINDS AT 700MB  
UNTIL NOON. OTHERWISE, REMAINING VERY DRY AND MOSTLY SUNNY TODAY  
WITH HOT TEMPERATURES IN THE UPPER 80S TO UPPER 90S ACROSS MOST  
OF THE AREA. A FEW LOCATIONS MAY END UP BEING A LITTLE WARMER  
COMPARED TO YESTERDAY WITH SOME ADDITIONAL RECORD HIGHS  
POSSIBLE, BUT WITH SURFACE WINDS SHIFTING INTO THE SOUTH,  
DECIDED TO KEEP HIGH TEMPERATURES NEAR OR SLIGHTLY ABOVE  
GUIDANCE THIS AFTERNOON. GUSTY WINDS THIS MORNING SHOULD  
GRADUALLY DIMINISH BY MID TO LATE AFTERNOON.  
 
A FEW NOTABLE CHANGES ON SUNDAY WITH MODELS TRENDING SLOWER WITH  
THE SURFACE COLD FRONT. WITH ALL MODELS DELAYING THE COLD FRONT  
UNTIL LATE SUNDAY EVENING (WEST OF I-25) AND LATE SUNDAY FOR  
AREAS EAST OF I-25, INCREASED HIGH TEMPERATURES INTO THE 80S AND  
LOW 90S AHEAD OF THE FRONT...MAINLY SOUTHEAST OF A LARAMIE TO  
LUSK LINE. FURTHER WEST ACROSS CARBON AND CONVERSE COUNTIES,  
EXPECT AFTERNOON TEMPERATURES TO GRADUALLY LOWER INTO THE 60S  
AND 70S AS THE FRONT NUDGES INTO THE AREA. WITH THIS DELAY,  
THERE HAS BEEN A NOTICEABLE INCREASE IN INSTABILITY AND MOISTURE  
ADVECTION AHEAD OF THE FRONT ACROSS EAST CENTRAL WYOMING AND  
THE NORTHERN NEBRASKA PANHANDLE. AGREE WITH SPC'S MARGINAL RISK  
FOR SEVERE THUNDERSTORMS IN THIS REGION WITH HIGH RES CAMS  
SHOWING ACTIVITY DEVELOPING BETWEEN 2 PM TO 6 PM SUNDAY  
AFTERNOON AND LINGERING THROUGH THE EVENING HOURS. INCREASED POP  
AND ADDED A CHANCE OF THUNDERSTORMS EAST OF THE I-25 CORRIDOR.  
AGAIN, SOME STRONG TO MARGINALLY SEVERE STORMS ARE POSSIBLE.  
 
MUCH COOLER AIR SPREADS ACROSS THE AREA SUNDAY NIGHT. IN FACT,  
MODEL GUIDANCE IS HINTING AT LOW TEMPERATURES A FEW DEGREES  
ABOVE FREEZING FOR THE HIGH VALLEYS...INCLUDING RAWLINS,  
SARATOGA, AND LARAMIE. WILL HAVE TO KEEP AN EYE ON THESE TRENDS  
OVER THE NEXT FEW DAYS FOR FROST OR FREEZE ADVISORIES. AT THIS  
TIME, KEPT LOWS TEMPERATURES AROUND 37 TO 39 DEGREES IN THESE  
LOCATIONS WITH MID 40S TO LOW 50S FURTHER EAST.  
 
FOR MONDAY, MODELS CONTINUE TO TREND A BIT WARMER DURING THE DAY  
WITH THE LACK OF A STRATUS DECK DEVELOPING DURING THE DAY, BUT  
STILL EXPECTED MONDAY NIGHT. MOISTURE ADVECTION SEEMS TO BE  
DELAYED UNTIL THE AFTERNOON HOURS...PROBABLY DUE TO LESS  
PROGRESSIVE NATURE OF THE FRONT ON SUNDAY. INCREASED HIGH  
TEMPERATURES A FEW MORE DEGREES WITH HIGHS IN THE LOW TO MID  
70S. STILL EXPECT A STRONG TEMPERATURE INVERSION AROUND 700MB,  
SO THERE SHOULD BE PLENTY OF CIN THROUGH THE MIDDLE OF THE  
AFTERNOON. HOWEVER, SHOWERS AND THUNDERSTORMS ARE POSSIBLE LATER  
IN THE DAY WITH INCREASING ELEVATED CAPE AND A WEAK DISTURBANCE  
ALOFT LIFTING NORTHEAST ACROSS THE FRONT RANGE. INCREASED POP  
UP TO 40 PERCENT FOR THUNDERSTORMS MONDAY EVENING.  
 

 
   
LONG TERM /MONDAY NIGHT THROUGH FRIDAY NIGHT/
 
 
ISSUED AT 320 AM MDT SAT JUN 21 2025  
 
NO MAJOR CHANGES TO THE LONG TERM PORTION OF THE FORECAST WITH  
ALL MODELS IN REASONABLE AGREEMENT. COOLER TEMPERATURES ARE  
EXPECTED WITH THE RETURN OF SHOWERS AND THUNDERSTORMS THE  
FOR MOST OF NEXT WEEK AS A SLOW MOVING PACIFIC UPPER LEVEL  
TROUGH MOVES EASTWARD ACROSS THE GREAT BASIN AND INTO THE  
ROCKYS. MODELS ARE TRENDING A LITTLE BIT WARMER EARLY TO MID  
NEXT WEEK COMPARED TO THE LAST SEVERAL MODEL RUNS, BUT STILL  
EXPECT BELOW AVERAGE TEMPERATURES IN THE UPPER 60S TO MID 70S  
THROUGH WEDNESDAY. SURFACE WINDS WILL SHIFT INTO THE EAST OR  
SOUTHEAST WITH EXCELLENT MOISTURE ADVECTION NEAR THE SURFACE.  
THIS WILL LIKELY RESULT IN SOME LOW STRATUS ACROSS THE EASTERN  
HIGH PLAINS AND CLOUDY SKIES FOR MONDAY NIGHT THROUGH TUESDAY  
NIGHT. HOWEVER, THIS MAY ALSO LIMIT DAYTIME AND EVENING  
CONVECTION. CAN'T RULE OUT THE POTENTIAL FOR STRONG OR SEVERE  
THUNDERSTORMS, ESPECIALLY TUESDAY AND WEDNESDAY AS THE PACIFIC  
TROUGH SLIDES EASTWARD INTO THE CONTINENTAL DIVIDE WITH DECENT  
SHEAR AND SBCAPE OF 1000 TO 1500 J/KG ACROSS A GOOD PORTION OF  
THE EASTERN PLAINS. HOWEVER, COVERAGE AND CONFIDENCE ARE PRETTY  
LOW AT THIS TIME WITH MARGINAL CONVECTIVE PARAMETERS AND 0-6KM  
SHEAR TRENDING LOWER AS WE HEAD INTO MID TO LATE WEEK. EXPECT  
ANOTHER SLOW WARMING TREND LATE NEXT WEEK BEHIND THE PACIFIC  
SYSTEM WITH HIGHS RETURNING TO THE 80S TO AROUND 90 ACROSS THE  
LOWER ELEVATIONS OF WESTERN NEBRASKA AND FAR EASTERN WYOMING.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
 
 
ISSUED AT 1150 PM MDT FRI JUN 20 2025  
 
UPPER LEVEL RIDGE AXIS WILL PUSH NORTHEAST ACROSS THE GREAT  
PLAINS AND GREAT LAKES REGION OVER THE NEXT 24 HOURS AS A PACIFIC  
COLD FRONT SLOWLY MOVES EASTWARD INTO CENTRAL WYOMING. THIS FRONT IS  
NOT EXPECTED TO PUSH INTO EASTERN WYOMING UNTIL SUNDAY MORNING.  
 
HAZARDS/WEATHER TRENDS: VFR CONDITIONS EXPECTED OVER THE NEXT 24  
HOURS UNDER MOSTLY CLEAR SKIES. BREEZY CONDITIONS ARE EXPECTED  
TONIGHT FOR KLAR AND KRWL WITH SOUTHWEST WINDS OCCASIONALLY GUSTING  
UP TO 25 TO 30 KNOTS AT TIMES. DO NOT EXPECT IT TO BE BREEZY ALL  
NIGHT WITH PERIODS OF LIGHTER WINDS EXPECTED. OTHERWISE, ANOTHER  
ROUND OF WINDY CONDITIONS AFTER 15Z SATURDAY FOR ALL SOUTHEAST  
WYOMING TERMINALS WITH SOUTH TO SOUTHWEST WINDS GUSTING UP TO 45  
KNOTS, AND UP TO 25 KNOTS FOR THE WESTERN NEBRASKA TERMINALS. WINDS  
ARE FORECAST TO EASE MID TO LATE AFTERNOON AFTER 21Z.  
 

 
   
CYS WATCHES/WARNINGS/ADVISORIES
 
 
WY...RED FLAG WARNING UNTIL 6 PM MDT THIS EVENING FOR WYZ421>423-  
425-427.  
HIGH WIND WARNING UNTIL 9 AM MDT THIS MORNING FOR WYZ110-115.  
 
NE...NONE.  
 

 
 

 
 
SHORT TERM...TJT  
LONG TERM...TJT/WFO CYS  
AVIATION...TJT  
 
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