699
FXUS65 KCYS 130805
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
205 AM MDT MON JUL 13 2026
KEY MESSAGES
- STRONG RIDGING ALOFT WILL PRODUCE A DRY AND HOT PERIOD FOR
TODAY THROUGH WEDNESDAY, WITH THE PRIMARY CHALLENGES BEING
THE ABOVE NORMAL HEAT AND FIRE WEATHER CONDITIONS.
- ISOLATED HIGH-BASED THUNDERSTORMS POSSIBLE ON THURSDAY THROUGH
SATURDAY MAINLY NEAR THE MOUNTAINS. ARRIVAL OF THE MONSOON
POSSIBLE LATER IN NEXT WEEKEND.
SHORT TERM /THROUGH TUESDAY NIGHT/
ISSUED AT 205 AM MDT MON JUL 13 2026
HELLO AGAIN FROM THE CHEYENNE OFFICE! THE UPPER LEVEL RIDGE WILL
REMAIN PARKED OVER THE INTERMOUNTAIN WEST TODAY KEEPING THE SKIES
RELATIVELY CLEAR FOR THE BETTER PART OF THE DAY. THE HIGH
TEMPERATURES WILL ONCE AGAIN BE IN THE 90'S TO 100'S TODAY. RH
VALUES WILL FLOAT BETWEEN 5 TO 15 PERCENT IN SOUTHEAST WYOMING AND
BETWEEN 15 AND 20 IN THE NORTHERN HALF AND 20 TO 30 IN THE SOUTHERN
HALF OF THE NEBRASKA PANHANDLE. THIS MEANS WHEN YOU'RE OUTSIDE IT
WILL BE A DRY HEAT AND WONT REALIZE YOU ARE SWEATING ESPECIALLY IF
YOU'RE IN CARBON COUNTY WHERE THE LOWEST RH VALUES ARE FORECASTED.
YOUR BODY WILL CONSTANTLY COOL YOURSELF THROUGH EVAPORATIVE COOLING
LEADING YOU TO DEHYDRATE FASTER. BECAUSE OF THESE HIGH SUMMER
TEMPERATURES THE HEAT ADVISORY WILL REMAIN IN PLACE ESPECIALLY SINCE
LARAMIE, WY IS STILL PRETTY MUCH THE ONLY PLACE TO DROP BELOW 70
DEGREES BEFORE MIDNIGHT-1AM. THE RED FLAG AND HEAT ADVISORY WERE
EXTENDED THROUGH WEDNESDAY NIGHT. THE PRESSURE GRADIENT REMAINS A
LITTLE TIGHT DURING THE DAY TO KEEP THE WINDS JUST BREEZY ENOUGH TO
WARRANT A RED FLAG. SO PLEASE CONTINUE TO DO EMS A FAVOR, HYDRATE
AND EAT SOME LIGHT SNACKS SO YOU KEEP NUTRIENTS AND VITAMINS IN YOUR
BODY TO PREVENT WATERLOGGING AND HEAT RELATED INJURIES.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
ISSUED AT 121 PM MDT SUN JUL 12 2026
THE WEATHER OVER THE MEDIUM TO LONG RANGE WILL BE DOMINATED BY
THE QUASI-STATIONARY UPPER LEVEL HIGH. THIS UPPER LEVEL HIGH
FORECAST TO REMAIN OVER THE SOUTH-CENTRAL TO CENTRAL UNITED
STATES, INCLUDING THE ROCKY MOUNTAIN REGION. THEREFORE, NOT
EXPECTING CONDITIONS TO CHANGE TOO MUCH THROUGH NEXT WEEK WITH
HOT TEMPERATURES. HOWEVER, RECORD HIGH ACTUALLY APPEAR UNLIKELY
AT THIS TIME SINCE WE ARE HEADING INTO THE WARMEST WEEK OF THE
YEAR, CLIMATOLOGICALLY SPEAKING. FOR EARLY IN THE WEEK, CENTER
OF THE 600DM UPPER LEVEL HIGH WILL BE GENERALLY LOCATED IN THE
CENTRAL ROCKY MOUNTAIN REGION EXTENDING EAST INTO THE CENTRAL
GREAT PLAINS. FORECAST HIGH TEMPERATURES WILL REMAIN IN THE 90S
FOR MOST OF SOUTHEAST WYOMING, INCLUDING THE HIGH VALLEYS WEST
OF THE LARAMIE RANGE. FOR WESTERN NEBRASKA, 95 TO 105 EXPECTED
EACH DAY. SOUTH TO SOUTHEASTERLY WINDS SHOULD CONTINUE EACH DAY
WITH INCREASING CONFIDENCE IN A DECENT BREEZY FOR THE LATE
MORNING HOURS AND THE AFTERNOON. THIS SHOULD RESULT IN SLIGHTLY
COOLER TEMPERATURES ACROSS THE SOUTH FACING RIDGES AND HILLS DUE
TO LOCALIZED UPSLOPE, BUT WE'RE TALKING ABOUT A DIFFERENCE
BETWEEN 91 AN 96 DEGREES, SO THE OVERALL COOLING WILL BE
MINIMAL.
AS WE HEAD INTO LATER IN THE WEEK AND THE WEEKEND, MODELS ARE NOW
SHOWING DIFFERENT SOLUTIONS IN REGARDS TO THE POSITION OF THE UPPER
LEVEL HIGH. THE 12Z ECMWF MAINTAINS THE UPPER LEVEL HIGH OVER
WYOMING, UTAH, AND NORTHERN COLORADO...SIMILAR TO YESTERDAY WHILE
THE GFS AND CANADIAN NOW SHOW THE CENTER OF THE HIGH DRIFTING
SOUTHEAST INTO THE SOUTH CENTRAL PLAINS. THE KEY DIFFERENCE BETWEEN
BOTH SOLUTIONS IN NOT NECESSARILY THE TEMPERATURES, WHICH IS STILL
EXPECTED TO BE VERY WARM TO HOT ACROSS THE FORECAST AREA, BUT
PRECIPITATION CHANCES. GFS AND CANADIAN SHOW THE MONSOON PLUME OVER
COLORADO AND WYOMING BY THE WEEKEND WITH INCREASING THUNDERSTORM
CHANCES. WILL KEEP AN EYE ON THIS TREND OVER THE NEXT FEW DAYS, WITH
A MENTION THUNDERSTORMS ALONG AND WEST OF THE INTERSTATE 25 CORRIDOR
FOR NOW.
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 1132 PM MDT SUN JUL 12 2026
BREEZY CONDITIONS ARE EXPECTED AT MOST OF THE NEBRASKA PANHANDLE
TERMINALS THIS EVENING AND TONIGHT AS A LOW-LEVEL JET DEVELOPS. WIND
GUSTS UP TO 25 KTS WILL BE POSSIBLE. SOUTHEAST WYOMING TERMINALS
CAN EXPECT LIGHTER WINDS. SIMILAR CONDITIONS ARE EXPECTED
TOMORROW WITH MOSTLY SUNNY SKIES AND DIURNAL AFTERNOON WIND GUSTS.
CYS WATCHES/WARNINGS/ADVISORIES
WY...RED FLAG WARNING UNTIL 8 PM MDT WEDNESDAY FOR WYZ417>420-423-
427-430>433.
HEAT ADVISORY UNTIL MIDNIGHT MDT WEDNESDAY NIGHT FOR WYZ101-
102-107-108-118-119.
NE...RED FLAG WARNING UNTIL 8 PM MDT WEDNESDAY FOR NEZ434>437.
HEAT ADVISORY UNTIL MIDNIGHT MDT WEDNESDAY NIGHT FOR NEZ002-
003-019>021-054-055-095-096.
SHORT TERM...MM
LONG TERM...TJT
AVIATION...SF
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