FXUS65 KCYS 191703 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 1103 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 NIGHT/... 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 /THURSDAY 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 /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1101 AM MDT Tue Aug 19 2025 VFR conditions will dominate at all terminals today and tomorrow with mainly clear skies forecast. Afternoon winds will generally favor around 10 knots east-southeasterly at CYS and the NE panhandle terminals. Overnight winds willbe generally light and follow drainage patterns at LAR and CDR. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...CG LONG TERM...CG AVIATION...MAC