


Area Forecast Discussion
Issued by NWS Cheyenne, WY
Issued by NWS Cheyenne, WY
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898 FXUS65 KCYS 092307 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 507 PM MDT Thu Oct 9 2025 .KEY MESSAGES... - Precipitation chances return for Friday into the weekend, mainly west of I-25. - The return of our annual strong winds is expected this weekend with gusty conditions possible for our wind prone regions. && .SHORT TERM /THROUGH SATURDAY/... Issued at 330 PM MDT Thu Oct 9 2025 Currently a pleasant afternoon across most of the area with mild temperatures and partly to mostly sunny skies. Radar shows a few light showers with some lightning strikes between Arlington and Pine Bluffs, however these do not seem to be causing any sort of disruptions or impacts. Per Hi-Res guidance, these showers will continue through the evening hours as a weak disturbance moves aloft. Overnight, clouds will begin to increase ahead of the next storm system, resulting in slightly warmer overnight lows. Heading into Friday, the upper-level pattern looks like that of a monsoon. With a 500 mb high over Texas and a trough off of the west coast, moist southwest flow will dominate. This southwest flow will bring a plume of moisture into the western half of the CWA. This moisture will begin to move in Friday morning, causing showers to develop over Carbon County. As the day progresses, these showers will spread eastward into Albany County and the Laramie Range. Despite rather impressive PWATs for this time of year, rainfall totals will be unremarkable as little forcing is present. A brief lull in shower activity will be possible during the evening hours before a stronger surge of moisture arrives Friday night. An upper-level disturbance moving across the CWA Friday night will provide weak lift need for stratiform precipitation to develop. Rain can be expected late Friday night across Carbon and Albany Counties. Rain will eventually move into areas east of the Laramie Range by Saturday morning. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 330 MDT Thu Oct 9 2025 The long term will be an active period as rain and strong winds are expected this weekend, followed by more chances for precipitation next week alongside cool, fall-like temperatures. Saturday the ridge will be shifting eastwards as a Pacific trough moves into the region. With plentiful moisture continuing to stream into the region and PWAT values 200-250% of normal, even approaching 300% in locations, any precipitation that can get going will have the potential to produce locally heavy rainfall, and will need to be monitored accordingly. Thankfully instability will be extremely meager, lucky to even reach 200 J/kg, so producing heavy showers or even a storm will likely be orographically driven. This is reflected in the forecast, with the bulk of any PoPs across our high terrain this weekend. Highs Saturday will remain in the 60`s to mid to upper 70`s thanks to the warm southwesterly flow from the influence of the ridge, but that changes moving into Sunday with the trough moving across. Highs west of the Laramie Range plummet, only reaching the 40`s to 50`s. Meanwhile the trough brings a jet that will move overhead and bring our first chance at seasonal high winds Saturday night through Sunday. At 700mb, speeds up to 60-70 kts are noted, which is conducive for high wind warnings, and our in house guidance agrees for the potential to briefly hit the criteria needed (58+ mph). The trough will sweep the moisture out of our region however, so look for precipitation chances to decline through the day Sunday. Moving into next week, the rest of the forecast period should be dominated by ridging and southwesterly flow, funneling moisture back into our area that will once again be limited by a lack of instability, keeping mountain precipitation the most likely outcome. Temperatures will steadily but slowly warm, with highs Monday in the 50`s, and then by Wednesday reaching back into the 60`s to low 70`s. A steady modest jet overhead should keep conditions breezy at times, but not nearly as gusty as Sunday. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1124 AM MDT Thu Oct 9 2025 Quiet weather is expected throughout the day today with mostly clear skies. A few clouds may drift into terminals west of the Laramie Range this afternoon, however these should not pose much of an impact. Light winds can be expected at most terminals, however, and occasional gust over 20 MPH will be possible. There is a slight chance of light showers around KCYS this evening. This could briefly reduce visibility. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...SF LONG TERM...CG AVIATION...SF