407
FXUS65 KCYS 060825
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
225 AM MDT MON JUL 6 2026
KEY MESSAGES
- REMAINING HOT ON MONDAY AS THE UPPER LEVEL RIDGE AXIS SHIFTS
EAST INTO THE PLAINS, EXPECT HIGHS TO TOP OUT IN THE UPPER 80S
TO UPPER 90S. A FEW LOCATIONS MAY REACH THE CENTURY MARK
ACROSS WESTERN NEBRASKA.
- CONDITIONAL THUNDERSTORM CHANCES RETURN MONDAY IN RESPONSE TO
INCREASING MOISTURE.
- STRONG TO MARGINALLY SEVERE THUNDERSTORMS POSSIBLE TUESDAY
THROUGH THURSDAY.
- A RIDGE BUILDS LATE IN THE LONG TERM, DRYING US OUT AND
PERHAPS BREAKING HEAT RECORDS.
SHORT TERM /THROUGH TUESDAY NIGHT/
ISSUED AT 225 AM MDT MON JUL 6 2026
MODELS CONTINUE TO BE IN GOOD AGREEMENT EARLY THIS WEEK WITH
VERY WARM/HOT CONDITIONS REMAINING OVER THE AREA FOR AT LEAST
ANOTHER DAY OR TWO. BREEZY EARLY THIS MORNING AS THE LOW LEVEL
JET REMAINS OVER THE HIGH PLAINS, WITH GUSTS AROUND 40 MPH
REPORTED AT CHADRON, AND GUSTS OF 20 TO 25 MPH ELSEWHERE ACROSS
WESTERN NEBRASKA AND EVEN FAR EASTERN WYOMING. THIS JET IS
IMPORTANT BECAUSE LOW LEVEL MOISTURE ADVECTION HAS BROUGHT
DEWPOINTS INTO THE 50S ACROSS THE EASTERN PLAINS, AND MID 40S
INTO ALBANY COUNTY. ALTHOUGH DAYTIME MIXING WILL BRING THESE
SURFACE DEWPOINTS DOWN A BIT, BOUNDARY LAYER MOISTURE SHOULD BE
SUFFICIENT TO START SEEING AN UPTICK OF THUNDERSTORM ACTIVITY
TODAY AND CONTINUING FOR MOST OF THE WEEK.
THE UPPER LEVEL RIDGE AXIS TODAY WON'T BE QUITE AS STRONG AS
SUNDAY AS THE RIDGE AXIS SHIFTS EASTWARD AND WEAKENS A BIT ONCE
A SUBTLE SHORTWAVE CLIPS THE NORTHERN ZONES LATE MONDAY
AFTERNOON. SOME MIDLEVEL COOLER AIR WILL ENTER THE AREA WHICH
SHOULD BE JUST ENOUGH TO INITIATE SOME SCATTERED RAIN SHOWERS
AND ISOLATED THUNDER ALONG AND EAST OF THE LARAMIE RANGE. KEPT
POP AROUND 15 TO 30 PERCENT THROUGH LATE MONDAY EVENING, HIGHEST
WHERE A LINE OF MULTICELL THUNDERSTORMS ATTEMPTS TO DEVELOP JUST
AHEAD OF THE SHORTWAVE DISTURBANCE. THIS LINE WILL STRUGGLE TO
GROW UPSCALE DUE TO LIMITED SHEAR, BUT WE CAN'T TOTALLY RULE IT
OUT EITHER. LARAMIE VALLEY MAY GET SOME OF THIS ACTIVITY EARLY
IN THE AFTERNOON, BUT BOUNDARY LAYER MOISTURE WILL BE LIMITED.
THUNDERSTORMS LOOK SUB-SEVERE AT THIS TIME WITH ONLY ABOUT 15
TO 20 KNOTS OF SHEAR AND MLCAPE BETWEEN 400 TO 800 J/KG,
HIGHEST OVER THE SOUTHERN NEBRASKA PANHANDLE. GUSTY
OUTFLOW/MICROBURST WINDS APPEAR TO BE THE MAIN THREAT FROM ANY
THUNDERSTORM ACTIVITY THIS AFTERNOON. OTHERWISE, HIGH
TEMPERATURES WILL BE SIMILAR TO SUNDAY WITH HIGHS IN THE UPPER
80S TO UPPER 90S. MAY SEE A FEW LOCATIONS REACH THE CENTURY MARK
ACROSS WESTERN NEBRASKA.
FOR TUESDAY, SLIGHTLY BETTER CONVECTIVE PARAMETERS AND SHEAR
COMPARED TO MONDAY WITH 0-6KM SHEAR NUDGING TOWARDS 25 TO 30
KNOTS BY THE END OF THE DAY. MODELS SHOW A BETTER DEFINED
SHORTWAVE LIFTING NORTHEAST OUT OF UTAH AND INTO EASTERN WYOMING
BY LATE TUESDAY AFTERNOON. WITH MOISTURE ADVECTION CONTINUING
OVER THE AREA, NAEFS SHOWS EAST CENTRAL WYOMING AND MOST OF THE
NEBRASKA PANHANDLE ABOVE THE 90TH PERCENTILE FOR PWAT AND
DEWPOINTS NEAR 60 DEGREES. HIGH RES CAMS SHOW A NOTICEABLE
UPTICK IN THUNDERSTORM COVERAGE WITH SOME ORGANIZED CELLS
SHOWING UP EAST OF I-25 DURING THE AFTERNOON. EXPECT SOME STRONG
TO MARGINALLY SEVERE THUNDERSTORMS TUESDAY AFTERNOON AND EVENING
WITH ISOLATED LARGE HAIL AND STRONG GUSTY WINDS. MODELS NOT IN
GOOD AGREEMENT WITH BOUNDARY LAYER MOISTURE ABOVE THE SURFACE
AND CAPE WITH THE GFS AS LOW AS 500 TO 1000 J/KG OF MLCAPE EAST
OF I-25, BUT THE NAM AS HIGH AS 2500 J/KG. WILL KEEP SEVERE
WORDING OUT OF THE FORECAST FOR NOW DUE TO THIS DISCREPANCY. A
SLIGHTLY COOLING TREND IS EXPECTED TO BEGIN ON TUESDAY WITH HIGH
TEMPERATURES STILL VERY WARM IN THE MID 80S TO MID 90S.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
ISSUED AT 131 PM MDT SUN JUL 5 2026
THE LONG TERM FEATURES SOME STORM CHANCES TO START OFF THE PERIOD
AND A SLIGHT COOLING TREND AS MONSOONAL MOISTURE ADVECTS IN FROM THE
WEST. BY NEXT WEEKEND THE RIDGE OVER THE FOUR CORNERS REGION MAY
STRENGTHEN PUSHING TEMPERATURES TOWARDS ALL TIME RECORD HIGHS.
WEDNESDAY AND THURSDAY FEATURE MUCH THE SAME WEATHER AS TUESDAY. THE
MOISTURE DOES POTENTIALLY INCREASE SOME ALLOWING MORE WIDESPREAD
PRECIPITATION CHANCES. WIND SHEAR DOES INCREASE, SO WE MAY SEE A FEW
MORE ORGANIZED STORMS WITH HAIL AND WIND THREATS. THE INCREASED
CLOUD COVERAGE AND STORMS MAY KEEP MOST OF THE REGION UNDER 90
DEGREES. THIS WILL BE POSSIBLY THE LAST GOOD CHANCE WE GET FOR
RAINFALL FOR SOME TIME AS THE RIDGE BUILDS OVER THE AREA. ENSEMBLE
MEMBERS HAVE THIS RIDGE REACHING SOME 8 TO 10 DECAMETERS ABOVE
CLIMATOLOGICAL AVERAGE. DETERMINISTIC MODELS HAVE UP TO 15 TO 18
DECAMETERS ABOVE AVERAGE. SUCH A STRONG RIDGE WILL CREATE
SIGNIFICANT SUBSIDENCE IN THE LOWER LEVELS, WARMING AND DRYING US
OUT. RELATIVE HUMIDITY VALUES IN THE SINGLE DIGITS AND TEMPERATURES
OVER 100 ARE CERTAINLY POSSIBLE OVER THE WEEKEND EAST OF I-25.
CRITICAL FIRE WEATHER WOULD ARISE FROM THESE CONDITIONS AND
RECEPTIVE FUELS. WHILE A WAYS OUT, THERE IS A POSSIBILITY THAT ALL
TIME RECORD HIGHS ARE BROKEN SUNDAY OR MONDAY AT A FEW LOCATIONS. IF
THE RIDGE CENTER SHIFTS TO OUR EAST WE ALSO HAVE A DOWNSLOPING
EFFECT THAT WOULD NUDGE TEMPERATURES UP A FEW DEGREES. HOPEFULLY THE
RIDGE ENDS UP NOT AS INTENSE AS MODELS ARE SUGGESTING.
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 1103 PM MDT SUN JUL 5 2026
VFR CONDITIONS ANTICIPATED FOR THE 06Z TAF PERIOD WITH GUSTY
WINDS SLOWLY DECREASING OVERNIGHT. KCDR WILL REMAIN QUITE GUSTY
OVERNIGHT WITH CONTINUING GUSTS BETWEEN 25 AND 30KTS. WINDS WILL
INCREASE AFTER AROUND 15Z FOR MOST TERMINALS. ISOLATED TO
SCATTERED SHOWERS AND STORMS MAY IMPACT TERMINALS IN THE
AFTERNOON. GUSTY AND ERRATIC WINDS ARE EXPECTED IN AND AROUND
ANY SHOWER OR STORM THE DEVELOPS IN THE AFTERNOON.
CYS WATCHES/WARNINGS/ADVISORIES
WY...NONE.
NE...NONE.
SHORT TERM...TJT
LONG TERM...RV
AVIATION...AM
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