


Area Forecast Discussion
Issued by NWS Cheyenne, WY
Issued by NWS Cheyenne, WY
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088 FXUS65 KCYS 310546 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 1145 PM MDT Sat Aug 30 2025 .KEY MESSAGES... - Scattered precipitation chances continue today, with drier conditions expected to return Sunday and through much of next week. - Warming trend starts Sunday with temperatures closer to, or slight above, seasonal averages. && .SHORT TERM /THROUGH MONDAY/... Issued at 210 PM MDT Sat Aug 30 2025 Scattered showers and storms ongoing this afternoon as the trough begins to move out of the region. Modest instability alongside PWAT values around 0.75-1 inch will continue to fuel moderate to occasionally heavy downpours through this evening, with rainfall rates approaching 1-2 inches per hour. A lack of favorable support however should preclude strong to severe storms, though an occasional stronger wind gust cannot be ruled out. Moving into Sunday the western ridge begins to overspread and take control, drying our CWA out and bringing calm conditions overall. Pressure gradients will be too weak to promote much more than light winds, and with most notable forcing to our east the only locations expected to see even a chance of precipitation will be Dawes County, but this is a low-end chance through the afternoon. With the ridging building we should also see temperatures on the rise, though highs for the day should still linger in the 70`s to low 80`s, remaining several degrees below normal for this time of year. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... Issued at 210 PM MDT Sat Aug 30 2025 Pleasant weather is in store to begin the week with limited chances of precipitation coupled with cooler temperatures across the CWA. One of the main synoptic features that will dominate weather conditions here locally will be a stout ridge that builds aloft across the western CONUS. This will allow drier air to flow into the region due to northwest flow aloft along with with slightly below normal temperatures. Temperatures will vary through the long term, with highs generally topping out in the 70s, with the warmest days being Monday and Tuesday, with temps climbing into the upper 70s across the western zones while the eastern forecast zones will enjoy the warmest temperatures as highs climb into the lower to mid 80s. With drier air in place for the majority of the long term, precipitation chances will be at a minimum. Global model solutions seem reasonably aligned for the long term with some subtle differences with the main features on the synoptic scale, an upper level ridge that builds across the western CONUS and a stout upper level low that dives south out of Canada into the Great Lakes region by late Wednesday into early Thursday. Ensemble members show a bit of discrepancy on how far west the edge of a much cooler airmass makes it to our CWA due to the upper level low coming out of Canada. GEFS members are mostly clustered on an eastward position of the trough while the ECMWF ensemble is more clustered westward. The GEFS solution would keep temperatures near normal while the ECMWF ensemble would bring much cooler temperatures into our CWA. Regardless of either ensemble scenario, expect limited rainfall chances through most of the long term. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1145 PM MDT Sat Aug 30 2025 Upper level ridge axis will slide east into western and central Wyoming over the next 24 hours. Drier conditions are expected with only a few isolated showers/thunderstorms possible across the northern Nebraska Panhandle. HAZARDS/WEATHER TRENDS: VFR conditions will prevail for the southeast Wyoming terminals late tonight and early Sunday morning. Expect low stratus to develop and move into KCDR, KAIA and possibly KSNY and KBFF after 09z. Some fog is also possible, but should be short-lived. low end MVFR CIGS and IFR CIGS are expected until 15z. Kept these conditions out of KBFF and KSNY for now due to lower confidence. VFR conditions expected for the rest of the day after 15z. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...CG LONG TERM...RZ AVIATION...TJT