FXUS65 KCYS 052029

AFDCYS



Area Forecast Discussion

National Weather Service Cheyenne WY

229 PM MDT Wed Aug 5 2026



.KEY MESSAGES...



- RED FLAG WARNING IN EFFECT UNTIL 8 PM MDT THURSDAY FOR GUSTY

  WINDS, LOW HUMIDITY, AND POOR OVERNIGHT RECOVERIES FOR

  LOCATIONS NEAR THE SNOWY RANGE AND FOOTHILLS AND THE MEDICINE

  BOW NATIONAL FOREST.



- RED FLAG WARNING IN EFFECT FROM 11 AM TO 8 PM MDT THURSDAY FOR

  GUSTY WINDS AND LOW HUMIDITY FOR MUCH OF SOUTHEAST WYOMING.



- HOT TEMPERATURES RETURN FOR THURSDAY THROUGH SUNDAY WITH

  SLIGHTLY COOLER TEMPERATURES FOR MONDAY THROUGH WEDNESDAY.



&&



.SHORT TERM /THROUGH THURSDAY NIGHT/...

Issued at 211 PM MDT Wed Aug 5 2026



Tonight...Another quiescent and nice night for leaving windows open 

as minimum temperatures dip into the 50s at lower elevations, with 

40s for the mountains. Northwest flow aloft prevails with a decent 

surface trough developing over southeast Wyoming. Looking at the 

boundary layer winds and 850 mb winds, expect to see a decent low 

level jet form across the Nebraska Panhandle, with south winds after 

midnight of 25 to 35 mph gusting to 45 mph at the usual suspects, 

Chadron and Alliance. The low level jet is likely to subside towards 

sunrise.



Thursday...The heat returns with a much drier airmass advecting 

eastward across our counties, and with 700 mb temperatures reaching 

14 to 18 Celsius, expect yielded high temperatures to be in the 

upper 80s to lower 90s west of I-25, with 90s to near 100 degrees 

east of I-25. Fortunately, relative humidities will be bone dry, 

making the apparent, or heat index temperatures in the tolerable 

range. 



Main challenge will be fire weather concerns with relative humdities 

only in the 5 to 15 percent range in the afternoon and early 

evening, and with projected mid level winds around 700 mb, 10000 

feet MSL, expected to mix down to the surface, we have felt it 

prudent and necessary to issue a Red Flag Warning for much of 

southeast Wyoming, with the only exceptions being southern Platte, 

southern Goshen and far eastern Laramie Counties where winds will 

not be at critical levels. Fortunately, the Nebraska Panhandle 

winds will remain below critical thresholds. Our Red Flag 

Warning will extend from 11 AM to 8 PM Thursday.



Thursday night...Quiet and tranquil weather will continue with a 

weak surface trough or weak cold front backing into our northeast 

Counties but with no sensible weather anticipated with cold frontal 

passage, only a switch to north and northeast winds north of a 

Douglas to Scottsbluff line. The airmass moderates with minimum 

temperatures in the mid to upper 50s at lower elevations, with 40s 

for the mountains, still quite pleasant sleeping weather to have 

windows open and fresh air from outside.

 

&&



.LONG TERM /FRIDAY THROUGH TUESDAY/...

Issued at 211 PM MDT Wed Aug 5 2026



With this synoptic setup, we will see much of the same weather 

over the forecast period. Friday starts us off with the ridge 

over our area. This will bring warm temperatures and dry air to 

the CWA. The 700mb temperatures are in the mid teens to lower 

20C, supporting warm temperatures across the CWA, before 

temperatures return to the mid teens on Tuesday, cooling the 

area down some. Fire weather will be a concern through this 

forecast period with dry air, gusty winds, and little to no 

chances of precipitation through Monday. Daytime RH values go 

down to the single digits to teens each day with little 

overnight recovery. Fire weather has the potential to become 

critical with any increases in winds. Monday afternoon through 

Tuesday, a trough starts building over the PNW, potentially 

drawing in some moisture and giving some relief to fire weather 

conditions as it nears closer to our area. 



&&



.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...

Issued at 1152 AM MDT Wed Aug 5 2026



Low clouds/CIGs are still impacting KSNY. Overcast clouds prevail at 

KSNY until later this afternoon when the clouds clear. All other 

terminals have cleared out the low clouds/CIGs from last night and 

are expected to continue having mostly clear skies. Winds are calm 

across all terminals except for KCYS and KLAR. KCYS and KLAR are 

expected to have winds gusting to 20 knots out of NNW this 

afternoon.



&&



.CYS WATCHES/WARNINGS/ADVISORIES...

WY...Air Quality Alert until 11 AM MDT Thursday for WYZ101>119.

     Red Flag Warning from 11 AM to 8 PM MDT Thursday for 

     WYZ417>425-428>430.

     Red Flag Warning until 8 PM MDT Thursday for WYZ426-427.

NE...None.



&&



$$



SHORT TERM...RUBIN

LONG TERM...ML

AVIATION...ML