912
FXUS65 KCYS 111131
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
531 AM MDT SAT JUL 11 2026
KEY MESSAGES
- STRONG RIDGING ALOFT WILL PRODUCE A DRY AND HOT PERIOD FOR
SUNDAY THROUGH TUESDAY, WITH THE PRIMARY CHALLENGES BEING THE
ABOVE NORMAL HEAT AND FIRE WEATHER CONDITIONS. ISOLATED HIGH
BASED THUNDERSTORMS WILL BE POSSIBLE ON WEDNESDAY OVER AND
NEAR THE MOUNTAINS, WITH COVERAGE SLOWLY INCREASING THURSDAY
AND FRIDAY, ALONG WITH AN ATTENDANT SLOW COOLING OF DAYTIME
MAXIMUM TEMPERATURES.
SHORT TERM /THROUGH SUNDAY NIGHT/
ISSUED AT 220 AM MDT SAT JUL 11 2026
THE UPPER LEVEL RIDGE BECOMES A LITTLE MORE STOUT AS IT BUILDS OVER
US. THE SUBSIDENT FLOW FROM THE UPPER LEVEL RIDGE WILL START TO MIX
IN DRY AIR FROM THE UPPER LEVELS OF THE ATMOSPHERE AND BRING IT DOWN
TO THE SURFACE. THIS WILL ALSO REDUCE THE NUMBER OF CLOUDS IN THE
SKY RAISING THE SURFACE HEATING EFFICIENCY IN OUR REGION. EVEN IN
SOUTHERLY FLOW THIS MAY HELP OVER PERFORM WHAT THE MODELS THINK THE
HIGH TEMPERATURE FOR THE DAY IS SUPPOSED TO BE. SO TODAY WILL BE
FAIRLY SUNNY WITH TEMPERATURES IN THE 90'S WITH SOME OF OUR NORTHERN
COUNTIES POSSIBLY REACHING 100 TODAY. HUMIDITY LEVELS WILL ALSO DROP
IN THE AFTERNOON TO AROUND 15 PERCENT OR LOWER IN SOUTHEAST WYOMING
AND AROUND 20-25 PERCENT FOR THE NEBRASKA PANHANDLE. WITH THE WINDS
EXPECTED TO BE LIGHT AND NO SHOWERS FORECASTED, THE ENVIRONMENT IS
IN AN ELEVATED FIRE STATE FOR TODAY. HOWEVER, IT IS INTERESTING TO
NOTE THAT THE NAM NEST, FV3, AND THE ARW WANT TO POPULATE SOME LIGHT
SHOWERS BETWEEN 18Z AND 21Z TODAY. THE NAM NEST HAS SOME SORT OF
STATIONARY BOUNDARY THAT ISN'T SEEN IN THE SURFACE OBSERVATIONS WITH
EASTERLY WINDS FORMING AN UPSLOPE CONVERGENCE BOUNDARY TO PRODUCE
SOME SHOWERS ALONG PLATTE AND GOSHEN COUNTY. THE NBM HAD RANDOM 12
POPS AROUND THAT TIME WITH QPF OUTPUTS NEAR A TENTH FORMING LITTLE
BULLSEYES ACROSS GOSHEN AND SIOUX COUNTY. THOSE WERE TAKEN OUT AS
THE SURFACE WILL BE TOO DRY AND THERE REALLY WONT BE MUCH TO LIFT
BUT WE SHALL SEE IF I'M WRONG OR NOT TODAY. FOR SUNDAY, THE FIRE
WATCH WAS UPGRADED TO A RED FLAG WARNING THAT NOW LASTS THROUGH
MONDAY EVENING. A SYSTEM WILL BE MOVING ACROSS CANADA COMPRESSING
AGAINST OUR RIDGE TO GIVE THE INTERMOUNTAIN WEST A BOOST IN GRADIENT
WINDS THAT LOOKS TO BE STRONG ENOUGH FOR THE RED FLAG CRITERIA WITH
GUSTS ABOVE 25 MPH. THE HEAT ADVISORY WAS EXTENDED AS WELL UNTIL 06Z
WEDNESDAY OR MIDNIGHT TUESDAY AS THE RIDGE REMAINS IN PLACE OVER US
FOR THAT LONG TO GIVE OUR REGION TEMPERATURES NEAR OR EXCEEDS 100
DEGREES DURING THE DAY AND WE DONT REALLY DROP BELOW 70 AT NIGHT
UNTIL 3-4AM LOOKING AT THE MODELS. SO THIS WEEKEND IS THE PERFECT
TIME TO GO OUT AND ENJOY THE LOCAL FESTIVITIES, HOWEVER JUST
REMEMBER TO STAY HYDRATED AND HAVE A COUPLE SNACKS TO PREVENT HEAT
INJURIES WHILE DOING THEM.
LONG TERM /MONDAY THROUGH FRIDAY/
ISSUED AT 1230 PM MDT FRI JUL 10 2026
SUNDAY THROUGH THURSDAY...PRIMARY CHALLENGES WILL BE THE HEAT AND
FIRE WEATHER CONDITIONS. A 5980 DEKAMETER 500 MB RIDGE LIES OVER
WYOMING SUNDAY MORNING, MOVING TO THE NORTHERN GREAT PLANES MONDAY
MORNING, AND THEN REMAINS ENTRENCHED ACROSS THE NORTHERN ROCKIES AND
NORTHERN GREAT PLANES THROUGH THE PERIOD. MODELS SUGGESTING TYPICAL
MONSOONAL MOISTURE CREEPING INTO OUR COUNTIES WEDNESDAY THROUGH
FRIDAY WITH WEAK PERTURBATIONS AND SOME MID LEVEL MOISTURE TO SPARK
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS OVER AND NEAR THE SNOWY
AND SIERRA MADRE RANGES, AS WELL AS THE SOUTHERN LARAMIE RANGE AND
LARAMIE VALLEY FROM WEDNESDAY THROUGH FRIDAY, WITH COVERAGE OF
STORMS SLOWLY INCREASING THROUGH THAT AFOREMENTIONED PERIOD.
RIDGING ALOFT DOMINATES OUR REGION, WITH QUITE DRY AIR AT LOW AND
MID LEVELS, ACCOMPANIED BY TYPICALLY TOASTY 700 MB TEMPERATURES,
THUS CHANCES FOR LATE DAY SHOWERS AND THUNDERSTORMS WILL BE NEARLY
NIL AND NON EXISTENT, AND DRY WEATHER WILL PREVAIL THROUGH TUESDAY.
THE 700 MB TEMPERATURES WILL YIELD MAXIMUM TEMPERATURES MAINLY IN
THE 90 TO 105 DEGREE RANGE. WEAK PERTURBATIONS AND A SLIGHT INCREASE
IN MID LEVEL MONSOONAL MOISTURE MAY SPARK ISOLATED HIGH BASED
THUNDERSTORMS ON WEDNESDAY, AND MORESO ON THURSDAY AND FRIDAY, AGAIN
DEPENDENT ON HOW MUCH MID LEVEL MONSOONAL MOISTURE ADVECTS INTO
OUR CWA, COUNTY WARNING AREA.
AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 528 AM MDT SAT JUL 11 2026
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. AN UPPER
LEVEL RIDGE WILL KEEP WINDS LIGHT AND SKIES RELATIVELY CLEAR
TODAY FOR OUR WYOMING TERMINALS. THE NEBRASKA TERMINALS MAY SEE
WIND GUSTS UP TO 25KTS THIS AFTERNOON AND INCREASING TO 30KTS
AFTER 00Z. GUSTY WINDS MAY STAY AROUND 20KTS THROUGH THE
OVERNIGHT PERIOD BUT DROPPING OFF AROUND 10Z.
CYS WATCHES/WARNINGS/ADVISORIES
WY...FIRE WEATHER WATCH FROM NOON MDT TODAY THROUGH SUNDAY MORNING
FOR WYZ417-418-423-430>433.
HEAT ADVISORY FROM NOON TODAY TO MIDNIGHT MDT TUESDAY NIGHT
FOR WYZ101-102-107-108-118-119.
RED FLAG WARNING FROM NOON SUNDAY TO 8 PM MDT MONDAY FOR
WYZ417>420-423-427-430>433.
NE...FIRE WEATHER WATCH FROM NOON MDT TODAY THROUGH SUNDAY MORNING
FOR NEZ434.
HEAT ADVISORY FROM NOON TODAY TO MIDNIGHT MDT TUESDAY NIGHT
FOR NEZ002-003-019>021-054-055-095-096.
RED FLAG WARNING FROM NOON SUNDAY TO 8 PM MDT MONDAY FOR
NEZ434.
SHORT TERM...MM
LONG TERM...RUBIN
AVIATION...MM
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