Area Forecast Discussion
Issued by NWS Cheyenne, WY
Issued by NWS Cheyenne, WY
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907 FXUS65 KCYS 241731 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 1131 AM MDT Fri May 24 2024 .KEY MESSAGES... - Precipitation chances Saturday and Sunday before winds return Sunday. A much warmer, milder week ahead as an upper-level ridge overtakes the region. && .SHORT TERM /THROUGH SUNDAY/... Issued at 340 AM MDT Fri May 24 2024 The windy weather pattern has slowly winded down overnight, with areas over the I-80 Summit and western Nebraska being the only regions remaining with wind gusts of 40-50+ mph as of 930Z. The mid-latitude cyclone responsible for the strong winds over our cwa, and severe weather across the Central Plains will move out toward the Upper Midwest/Great Lakes area by much later today. In its wake, we will see surface high pressure dominate the region. Slightly cooler temperatures will be present, as daytime highs in the 60s are forecast for today, and slightly cooler in the higher terrain. Increasing clouds from the south will move north by this evening, keeping temperatures slightly elevated overnight. Shortwave disturbances will propagate along the H5 flow aloft for Saturday, and this is going to be our next opportunity for rain showers and isolated thunderstorms. However, the energy associated with the flow aloft, and lee-side troughing east of the mountain ranges will limit the strength of any convection that initiates. We will have the potential for a few locations to see wetting rainfall in excess of 0.10 inches. This would be well received as there are increasing concern for drought as the late spring period continues. Saturday night, model guidance is trending towards another weak mountain wave event for southeast Wyoming. 700mb winds are progged to creep north of the 50 knot threshold by 12Z Sunday. In fact, some areas along the spine of the Laramie Range could exceed 60-65 knots. This wind speed coupled with the upward/downward motion from modeled omega fields depict a swath of elevated to strong wind gusts reaching the surface. The areas of Arlington, I-80 Summit, and Bordeaux are favored the most for this to be realized. The eastern foothills off the Laramie Range may also see the stronger wind gusts of 60+ mph from Sunday morning into the early afternoon. Isolated rain showers in our norther forecast zones are possible from Sunday morning into the afternoon hours as the shortwave disturbance responsible for the winds quickly ejects eastward. Daytime highs in the 60s and 70s for the lower terrain will be expected, and it should be a pleasant holiday weekend for those that plan to be outdoors. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Issued at 340 AM MDT Fri May 24 2024 Surface frontal boundary looks to lay along a line from Kimball to Wheatland to just north of Riverton Sunday evening. Upper shortwave tracks across northeastern Wyoming Sunday evening that may drive the cold front south into the central CWA. GFS/ECMWF looks to be dry on PoPs through as this front shifts south. If anything...maybe Converse and Niobrara Counties may see a few showers early Sunday evening. Memorial Day looking dry still as 500mb heights are on the rise as a flat ridge builds into western and central Wyoming. Upper ridge axis shifts east into western Nebraska and western South Dakota Tuesday afternoon and evening. May start to see increasing chances for showers Tuesday afternoon across our western mountains and possibly as far east as Cheyenne into the evening hours. Better chances Wednesday as next shortwave begins to move into the western part of the state. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1131 AM MDT Fri May 24 2024 Quiet conditions expected through the day. Diurnal wind gusts of 20 to 30 kts possible at all terminals this afternoon, with winds easing this evening. Expect increasing clouds through the evening hours as a weak disturbance brings a chance of showers late tonight. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...BW LONG TERM...GCC/AM AVIATION...SF