463
FXUS65 KCYS 151140
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
540 AM MDT FRI AUG 15 2025
KEY MESSAGES
- ISOLATED TO WIDELY SCATTERED PM SHOWERS AND THUNDERSTORMS WILL
CONTINUE TODAY AND THROUGH THE WEEKEND WITH SLIGHTLY COOLER
TEMPERATURES THIS WEEKEND.
- HOT AND DRY CONDITIONS RETURN FOR THE UPCOMING WORK WEEK WITH
ONLY MINIMAL PRECIPITATION CHANCES.
SHORT TERM /THROUGH SATURDAY NIGHT/
ISSUED AT 245 AM MDT FRI AUG 15 2025
QUIET WEATHER EARLY THIS MORNING WITH SCATTERED CLOUDS AND LIGHT
WINDS OVER SOUTHEAST WYOMING AND WESTERN NEBRASKA. TEMPERATURES
HAVE STAYED RELATIVELY MILD WITH MOSTLY CLOUDY SKIES FOR MUCH OF
LAST NIGHT, WITH TEMPERATURES IN THE 60S AND 70S. AS THESE
CLOUDS DISSIPATE, EXPECT LOWS TO BOTTOM OUT IN THE UPPER 50S TO
MID 60S. FOR THE REST OF TODAY, ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS EXPECTED AS THE MID TO UPPER LEVEL FLOW BACKS INTO
THE SOUTH AHEAD OF A QUICK MOVING PACIFIC UPPER LEVEL TROUGH.
SURFACE WINDS ARE EXPECTED TO SHIFT INTO THE EAST OR SOUTHEAST
WITH DECENT LOW LEVEL MOISTURE ADVECTION. KEPT POP BETWEEN 30 TO
50 PERCENT ACROSS A GOOD PORTION OF SOUTHEAST WYOMING AS THE
UPPER LEVEL TROUGH SLIDES NORTHEAST ACROSS THE AREA TODAY.
CONVECTIVE PARAMETERS AREN'T VERY IMPRESSIVE AND SIMILAR TO
YESTERDAY. STILL, WEAK THUNDERSTORMS AND SHOWERS PRODUCED
SEVERAL WIND GUSTS OVER 50 MPH, SO EXPECT SIMILAR CONDITIONS
THIS AFTERNOON. THERE IS A BETTER CHANCE FOR HAIL, BUT
PERSISTENT 0-6 KM SHEAR IS LACKING ACROSS THE AREA AND DEWPOINTS
WILL ONLY PEAK AROUND 40 TO 45 DEGREES ACROSS MOST OF SOUTHEAST
WYOMING, WITH MID 50 DEGREE DEWPOINTS OVER WESTERN NEBRASKA.
THIS SHOULD BE ENOUGH TO JUSTIFY THE MARGINAL RISK FOR SEVERE
THUNDERSTORMS OVER THE HIGH PLAINS THIS AFTERNOON AND THIS
EVENING. NOT QUITE AS HOT TODAY WITH HIGHS IN THE 80S TO LOW 90S
ALONG AND WEST OF THE INTERSTATE 25 CORRIDOR, AND LOW TO MID 90S
FOR FAR EASTERN WYOMING INTO WESTERN NEBRASKA. THIS SLOW COOLING
TREND IS FORECAST TO CONTINUE INTO THIS WEEKEND.
SATURDAY WILL LIKELY BE THE COOLEST FOR THE NEXT 7 DAYS WITH
HIGHS IN THE 80S FOR MOST OF THE REGION, WITH LOW 90S BELOW 4500
FEET. ANOTHER UPPER LEVEL DISTURBANCE WILL PUSH NORTHEAST ACROSS
THE AREA...AROUND THE UPPER LEVEL HIGH PRESSURE TO OUR
SOUTHEAST. MODELS SHOW SOME DECENT JET ENERGY WITH THIS
DISTURBANCE AS IT LIFTS NORTHEAST AND THEN EAST ACROSS THE HIGH
PLAINS. MODELS ARE NOT IN GOOD AGREEMENT WITH THE TIMING AND
PLACEMENT OF THE DISTURBANCE THOUGH, WITH THE ECMWF SHOWING IT
MORE PROGRESSIVE AND ALREADY MOVING INTO THE DAKOTAS BY THE
AFTERNOON HOURS...WHICH WILL RESULT IN LESS COVERAGE OF SHOWERS
AND THUNDERSTORMS FOR OUR AREA. LOWERED POP A BIT COMPARED TO
NBM AND KEPT THEM CLOSER TO THE GRAND ENSEMBLE MEANS. AGAIN,
CONVECTIVE PARAMETERS AREN'T TOO IMPRESSIVE WITH 0-6KM SHEAR
AROUND 20 TO 25 KNOTS FOR MUCH OF THE AREA.
LONG TERM /SUNDAY THROUGH THURSDAY/
ISSUED AT 227 PM MDT THU AUG 14 2025
ANOTHER WEEK OF HOT AND MOSTLY DRY WEATHER EXPECTED FOR THE REGION
AS AN UPPER-LEVEL RIDGE REMAINS LARGELY PARKED OVERHEAD. GENERALLY
SOUTHWESTERLY FLOW WILL BE PRESENT OVERHEAD LATE SATURDAY
THROUGH MONDAY, WHICH WILL ENABLE DAILY AFTERNOON SHOWER AND
STORM CHANCES ACROSS THE REGION AS THE HIGHER TERRAIN ACTS TO
INITIATE STORMS. THESE SHOWERS AND STORMS WILL NOT BE WIDESPREAD
AND WILL LIKELY PRODUCED LIMITED PRECIPITATION TOTALS DUE TO
THE DRY CONDITIONS ONGOING ACROSS THE REGION. TUESDAY AND
WEDNESDAY WILL BE TRANSITIONS DAYS AS AN UPPER-LEVEL HIGH PUSHES
INTO THE FOUR CORNERS REGION AND FLOW OVER THE CWA TURNS MORE
WESTERLY TUESDAY AND THEN NORTHWESTERLY FOR WEDNESDAY. AS A
RESULT, PRECIPITATION CHANCES WILL BE EVEN MORE LIMITED TUESDAY
AND ESPECIALLY WEDNESDAY AS THAT HIGH MOVES CLOSER TO THE CWA
AND BECOMES MORE DOMINANT. THIS DOMINANT HIGH WILL REMAIN
OVERHEAD FOR THE REMAINDER OF THE WEEK, LEADING TO VERY DRY AND
WARM CONDITIONS THURSDAY ONWARDS. THE WARMEST DAY IN THE LONG
TERM LOOKS TO BE MONDAY AT THIS TIME, THOUGH THURSDAY AND FRIDAY
LOOK TO INCH CLOSER TO THE 100F MARK ACROSS THE PANHANDLE. WITH
MINIMAL PRECIPITATION AND WARM AND DRY CONDITIONS, FIRE WEATHER
CONDITIONS WILL LIKELY RETURN TO THE ELEVATED LEVEL.
THANKFULLY, WINDS LOOK TO BE FAIRLY CALM DURING THE WEEK, SO RED
FLAG CONDITIONS MAY NOT BE MET. EITHER WAY, WITH HOT AND DRY
CONDITIONS, FIRES WILL BE MORE LIKELY TO START AND SPREAD MORE
EASILY, SO USE CAUTION IF BURNING OUTDOORS OR CAMPING.
AVIATION /12Z TAFS THROUGH 12Z SATURDAY/
ISSUED AT 540 AM MDT FRI AUG 15 2025
UPPER LEVEL RIDGE WILL REMAIN OVER THE CENTRAL PLAINS WHILE A RIDGE
AXIS EXTENDING NORTHWEST INTO WYOMING AND COLORADO. AN UPPER LEVEL
DISTURBANCE WILL PUSH NORTH OUT OF COLORADO TODAY, RESULTING IN
ANOTHER ROUND OF SHOWERS AND WIDELY SCATTERED THUNDERSTORMS.
HAZARDS/WEATHER TRENDS: VFR CONDITIONS EXPECTED EARLY THIS MORNING
THROUGH THE AFTERNOON HOURS. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS ARE FORECAST TO DEVELOP AROUND 18Z TO 20Z ACROSS THE
MOUNTAINS, AND MAINLY IMPACT KCYS AND KLAR THROUGH THE LATE
AFTERNOON. THESE THUNDERSTORMS WILL EVENTUALLY MOVE INTO WESTERN
NEBRASKA BETWEEN 23Z TODAY AND 04Z SATURDAY. BRIEF MVFR VIS AND
GUSTY WINDS UP TO 40 KNOTS POSSIBLE WITH THIS ACTIVITY. ADDED PROB30
FOR TS AND -TSRA FOR MOST TERMINALS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...TJT
LONG TERM...AM/TJT
AVIATION...TJT
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