427
FXUS65 KCYS 132336
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
536 PM MDT SAT JUN 13 2026
KEY MESSAGES
- A REINFORCING COLD FRONT WILL MOVE ACROSS THE FORECAST AREA
SATURDAY, LEADING TO BELOW AVERAGE TEMPERATURES THROUGH THE
WEEKEND WITH SLIGHT CHANCES FOR PRECIPITATION.
- FIRE WEATHER CONCERNS INCREASE SIGNIFICANTLY MONDAY THROUGH AT
LEAST FRIDAY, WITH DRY, BREEZY CONDITIONS AND VERY WARM
TEMPERATURES. MINIMAL PRECIPITATION EXPECTED AT THIS TIME.
SHORT TERM /THROUGH SUNDAY NIGHT/
ISSUED AT 136 PM MDT SAT JUN 13 2026
VISIBLE SATELLITE IMAGERY CURRENTLY SHOWS THE LOCATION OF A
REINFORCING COLD FRONT DROPPING DOWN FROM NORTHERN WYOMING AND SOUTH
DAKOTA. A STRATUS DECK SLOWLY MAKING ITS WAY SOUTH CAN BE SEEN FROM
SATELLITE WITH OBSERVATIONS SHOWING NORTH WINDS UNDER THIS
CLOUD DECK. OBSERVATIONS FROM THE NORTHERN ZONES BEHIND THE
FRONT ALSO SHOWED A DROP IN TEMPERATURE WITH THE FRONTAL
PASSAGE. TEMPERATURES BEHIND THE FRONT ARE SITTING IN THE 40S
AND 50S AND WILL ONLY WARM ABOUT 5 TO 10 DEGREES THROUGH THE
REMAINDER OF THE AFTERNOON. AS THE FRONT CONTINUES SOUTH, OTHER
LOCATIONS WILL BE AFFECTED BY THE NOTICEABLY COOLER
TEMPERATURES. HIGHS THIS AFTERNOON WILL RANGE FROM THE UPPER 50S
TO 60S FOR THE NORTHERN HALF OF THE CWA AND 60S TO MID 70S FOR
THE SOUTHERN HALF. THESE TEMPERATURES ARE ACTUALLY ABOUT 5 TO 10
DEGREES COOLER THAN AVERAGE. THE UPPER-LEVEL SHORTWAVE
ASSOCIATED WITH THE COLD FRONT WILL ALSO HAVE SOME MID-LEVEL
MOISTURE WITH IT. WITH UPPER-LEVEL DYNAMIC SUPPORT FROM
VORTICITY MAXES, CANNOT RULE OUT A FEW LIGHT SHOWERS DEVELOPING
IN AND AROUND THE PINE RIDGE AREA THIS AFTERNOON. HI-RES
GUIDANCE HAS ANY SHOWER ACTIVITY ENDING AND OUT OF THE AREA BY
THIS EVENING.
OVERNIGHT, WINDS BEHIND THE FRONT WILL WEAKEN AND TURN MORE
EASTERLY, ESPECIALLY IN THE VICINITY OF THE CHEYENNE RIDGE
AREA. THE WEAK EASTERLY FLOW WILL PUT MUCH OF THE INTERSTATE 25
CORRIDOR AND SOUTHERN NEBRASKA PANHANDLE IN AN UPSLOPE REGIME,
LEADING TO LOW STRATUS ACROSS MUCH OF THIS AREA. CANNOT RULE OUT
SOME PATCHY FOG DEVELOPING SUNDAY MORNING IN THE SAME AREA,
HOWEVER MODEL SOUNDINGS FROM THE GFS STILL SHOW A RELATIVELY DRY
SURFACE, WITH HREF FOG PROBABILITIES ALSO LOW AT THIS TIME.
WITH STRATUS EXPECTED TO LINGER THROUGH MUCH OF THE DAY,
TEMPERATURES WILL ONCE AGAIN BE ON THE COOLER SIDE, WITH HIGHS
MAINLY IN THE 60S ACROSS THE CWA. HI-RES GUIDANCE ONCE AGAIN
HINTS AT THE POTENTIAL FOR SOME LIGHT SHOWERS/SPRINKLES DURING
THE DAY SUNDAY, HOWEVER, THE SATURATED LAYER IS QUITE SHALLOW,
SO ANY SHOWERS THAT DO DEVELOP WILL LIKELY HAVE LITTLE
PRECIPITATION WITH THEM. AS THE DAY PROGRESS, CLOUDS WILL
GRADUALLY LIFT AND CLEAR OUT, WITH PARTLY TO MOSTLY CLEAR SKIES
BY THE EVENING.
LONG TERM /MONDAY THROUGH SATURDAY/
ISSUED AT 136 PM MDT SAT JUN 13 2026
MONDAY MORNING, ANOTHER WEAK SHORTWAVE LOOKS TO PUSH
THROUGH THE INTERMOUNTAIN WEST AHEAD OF THE RIDGE PUSHING EASTWARD
OFF THE WEST COAST. HOWEVER, AS THIS RIDGE PUSHES EASTWARD, THE
RIDGE BEGINS TO FLATTEN DUE TO ANOTHER LOW PRESSURE SYSTEM PUSHES
INTO BRITISH COLUMBIA AND TRAVELS ALONG THE CANADIAN PROVIDENCES
UNTIL DROPPING INTO THE NORTHERN PLAINS AROUND WEDNESDAY EVENING.
THIS WILL CHANGE THE FLOW DIRECTION FROM NORTHWEST ON MONDAY AND
TRANSITION TO A WESTERLY DOWNSLOPE BY TUESDAY EVENING. THIS CHANGE
OF FLOW WILL RESULT IN SURFACE TEMPERATURES INCREASING FROM THE 70'S
ON MONDAY TO THE 80'S AND 90'S TUESDAY THROUGH POSSIBLY FRIDAY WITH
BREEZY TO RATHER GUSTY WINDS WHILE IN THE DOWNSLOPING FLOW TO
DEVELOP ANOTHER FEW DAYS OF RED FLAG CONDITIONS. BORDERLINE HIGH
WINDS FOR THE PANHANDLE AND I-80 CORRIDOR MAY DEVELOP AS A BRIEF
700MB JET IS CREATED FROM THE TROUGH PASSING THROUGH THE HIGH PLAINS
AS PROGGED SPEEDS REACH 50-55KTS. BEHIND THE TROUGH WINDS LOOK TO
RESUME THEIR NORTHWEST FLOW ON THURSDAY BEFORE A SHORTWAVE CAUSES
THE WINDS TO BECOME GUSTY AND VARIABLE ON FRIDAY.
AVIATION /00Z TAFS THROUGH 00Z MONDAY/
ISSUED AT 532 PM MDT SAT JUN 13 2026
A COLD FRONT IS PUSHING UP AGAINST THE HIGHER TERRAIN THIS
EVENING, WHICH WILL LEAD TO NORTH TO NORTHEAST WINDS OVER THE
PLAINS AND AT RWL. EAST WINDS AT LAR WILL TURN SE SUNDAY
MORNING. OVER THE PLAINS, EXPECT A FEW MORE HOURS WITH GUSTS OF
20 TO 30 KNOTS POSSIBLE, AND THEN WINDS WILL WEAKEN LATE THIS
EVENING. RWL AND LAR WILL HAVE THE POTENTIAL TO SEE GUSTY WINDS
IN THE 20 TO 30 KNOT RANGE THROUGH SUNDAY MORNING.
CLOUD COVER WILL ALSO INCREASE OVERNIGHT. THE HIGHEST CONFIDENCE
IN MVFR IS AT LAR AND CYS, WHILE OTHER TERMINALS SHOULD REMAIN
IN THE 3K TO 5K FT RANGE. WHILE MVFR IS CURRENTLY FAVORED, THERE
IS ABOUT A 40% CHANCE FOR IFR CIGS SUNDAY MORNING AT CYS. A FEW
LIGHT SHOWERS WILL ALSO DEVELOP AFTER MIDNIGHT AND CONTINUE
THROUGH ABOUT NOON SUNDAY. PRECIPITATION RATES WILL BE FAR TOO
LIGHT TO CAUSE VIS DISRUPTIONS, BUT WE MAY SEE SOME
DRIZZLE/SPRINKLES. VCSH WAS ADDED TO MENTION THIS POSSIBILITY.
LOOK FOR GRADUALLY CLEARING SKIES SUNDAY WITH LARGELY LIGHT AND
OCCASIONALLY VARIABLE WINDS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...SF
LONG TERM...MM
AVIATION...MN
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