667 FXUS65 KCYS 110707 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 107 AM MDT Fri Apr 11 2025 .KEY MESSAGES... - Well above normal temperatures continue through Saturday with dry weather forecasted. - A cold front will arrive on Sunday dropping temperatures back to near climatological average for Sunday and Monday. && .SHORT TERM /THROUGH SATURDAY/... Issued at 1249 AM MDT Fri Apr 11 2025 Very mild and dry weather will dominate most of the short-term period as high pressure remains in control over the western CONUS. Rising heights and warming mid-level temperatures will result in afternoon highs increasing to around 20 degrees above normal today in both Wyoming and western Nebraska, with afternoon highs over 25 degrees above normal on Saturday. Record high temperatures will be possible on both days, particularly on Saturday when the ridge axis passes just east into the high plains. Afternoon winds will remain relatively light on Friday, with southwesterly flow increasing on Saturday afternoon in the Wyoming high country ahead of an approaching cold front. The Saturday evening forecast remains the only slight challenge in the short-term. Height falls will spread southward ahead of the cold front/trough lurking just to the north over the northern high plains. As mid-level moisture increases ahead of this system, a few isolated convective updrafts may develop in the higher terrain of the Laramie Range and head east into Converse and Niobrara counties in east-central Wyoming. This scenario is portrayed in the longer-range CAM guidance including both the NAM Nest and FV3 HREF members. Isolated gusty winds and perhaps a rumble of thunder would accompany any very high-based convection that can form, which would take place in the 0z-5z timeframe Saturday evening. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 300 PM MDT Thu Apr 10 2025 Starting Saturday evening, an upper wave trough will be pushing through the Rocky mountains to give us some light precipitation chances Sunday. The parent low pressure system will be descending into the Northern Plains Sunday producing a cold front that will push southward through the Intermountain West. This cold front looks to help us saturate at the lower levels allowing for some precipitation to reach the surface. Instead of being a more stratiform rainfall this currently has the looks to be more showery in nature meaning its going to be hard to determine how much rain will actually fall to the ground at each location. The winds look to increase Sunday behind the cold front to give us some potentially elevated winds for our wind prone areas. Also behind the cold front, the Intermountain West will be in northwest flow allowing for a cooler airmass to descend down from Canada. This cooler airmass will knock temperatures into the 50`s with overnight temperatures in the 20`s and 30`s Sunday and Monday. Tuesday, An upper level ridge begins to build over the West coast and shifting eastward to the Rocky Mountains. The 700mb pressure gradient will tighten giving us another potentially windy day Tuesday and Wednesday but doesn`t currently look like any high wind headlines may be needed. Our in- house high wind algorithm isn`t showing any excitement past the Sunday elevated wind event which currently meets our expectations for next weeks weather pattern. && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 545 PM MDT Thu Apr 10 2025 Upper level ridge axis will push over the area tonight and Friday and will result in quiet weather with minimal impacts to aviation. HAZARDS/WEATHER TRENDS: VFR conditions expected over the next 24 hours, with breezy conditions expected between 17z and 01z, including this evening, with gusts up to 20 knots possible. Otherwise, winds will be light and variable. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...MAC LONG TERM...MM AVIATION...MM