FXUS65 KCYS 190849

AFDCYS



Area Forecast Discussion

National Weather Service Cheyenne WY

249 AM MDT Tue Aug 19 2025



.KEY MESSAGES...



- Hot temperatures with more limited thunderstorm chances are

  expected Tuesday through Thursday.



- Active weather returns Thursday and continues through early

  next week as multiple days of showers and thunderstorms

  alongside cooler temperatures are expected.



&&



.SHORT TERM /THROUGH WEDNESDAY/...

Issued at 1256 AM MDT Tue Aug 19 2025



Short term forecast period will be rather quiet and warm as we

see a Four Corners ridge build and firmly take hold of our

region today and tomorrow. Highs today continue to steadily

build, with portions of the northern Nebraska Panhandle

approaching triple digits while the rest of our CWA experiences

upper 80's to mid 90's, with our region then rising another

couple to few degrees on Wednesday with even more widespread

near triple digit heat. While widespread record setting highs

are not expected, a few stations could tie to possibly just 

break daily records.



Otherwise under this ridging the rest of our weather will remain

mostly quiet. Pressure gradients will remain limited and we

should see some diurnally driven afternoon and evening gusty

winds. Thankfully these winds are not expected to be co-located

with portions of the region that experience critically low

daytime minimum RH values, as our western zones are expected to

drop down into the teen to single digit values each day. This

will still encourage an enhanced fire weather environment, but

critical conditions are currently not expected. Finally, some

high res guidance is indicating the potential for very isolated

precipitation chances this evening mainly firing off of the

Laramie Range, but with how dry our lower levels and surface are

and inverted V soundings present, expectation is that a few high

high based cells may form and struggle to precipitate all the 

way to the surface before quickly falling apart. Can't rule out

a few lightning strikes with this though.





&&



.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...

Issued at 1256 AM MDT Tue Aug 19 2025



Long term will see a significant pattern change as we should

cool off notably and bring daily shower and thunderstorm chances

across the CWA. A cold front will begin moving across the region

starting on Thursday, but will be slow enough that we should

still see widespread upper 80's to upper 90's for one final day

of warmer than average temperatures. This boundary is a feature

associated with a large upper level low that's expected to move

across Canada and then begin slowing near the Great Lakes, which 

will cause the Four Corners ridge to begin retreating to the 

southwest and allow a northwesterly flow pattern to establish. 

This will then allow for several smaller disturbances to ride 

the periphery between these two features and straight over our 

area, while also allowing a surge of monsoonal moisture to 

overspread with PWAT values climbing up to 125-150% of normal.

For Thursday through next Monday, this means expect daily 

chances of scattered to widespread showers and thunderstorms, 

periods of which could be strong to severe (though it remains 

too far out to make any certain forecasts on the strength of 

them at this time), alongside highs on average 3 to 8 degrees 

below normal for this time of year (70's to low 80's). And of 

course this moisture should help negate our fire weather 

concerns, so expect our dry conditions to take a backseat for 

now.



&&



.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...

Issued at 1050 PM MDT Mon Aug 18 2025



Period of quiet weather expected to begin Tuesday as a strengthening 

upper level high pressure over Colorado dominates the weather 

pattern across the Front Range. 



HAZARDS/WEATHER TRENDS: VFR conditions will prevail over the next 24 

hours. After a period of gusty southerly winds for KCYS and KLAR, 

winds should become light out of the south or southeast. Expect this 

to continue through Tuesday with gusts up to 20 knots. Can't rule 

out a few showers or thunderstorms for the southeast Wyoming 

terminals, but due to limited coverage (very isolated), kept out of 

those TAFs for now.



&&



.CYS WATCHES/WARNINGS/ADVISORIES...

WY...None.

NE...None.



&&



$$



SHORT TERM...CG

LONG TERM...CG

AVIATION...TJT