478 FXUS65 KCYS 262038 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 238 PM MDT Thu Jun 26 2025 .KEY MESSAGES... - Fire weather conditions are probable for Western portion of the forecast area tomorrow. - Warm temperatures and daily coverage of scattered afternoon and evening showers and thunderstorms expected for the weekend through Thursday. && .SHORT TERM /THROUGH FRIDAY/... Issued at 235 PM MDT Thu Jun 26 2025 Looking at Water Vapor imagery, there's a lot of dry air at the lower levels that keeps us from getting some scattered showers as a small shortwave pushes through the intermountain west later this afternoon/evening. There may be quick isolated showers as some moisture floats in from the midlevels as seen on water vapor, but it's uncertain if it will be enough to spark anything. Most of the more abundant water vapor is still shown to be in the Pacific Northwest. As the shortwave moves through there may be around a couple hundred joules of CAPE still left but doesn't look like it may be enough to produce anything strong or severe. A few bolts of lightning may still be generated along with some thunder and light rain. Models depict most of these showers will be contained in the mountains if they were to develop. Friday, Looks to be almost the same scenario as a weak shortwave looks to push through the Intermountain West. Friday, will also be a little bit warmer with temperatures in the 80's east of I-25 and in the 70's possibly 80's in the mountains. There is a little more CAPE especially in the Panhandle with progged values around 1000-1500 j/kg. However, most models have the storms developing mostly in the Panhandle where the moisture is a little better with the higher CAPE values. SPC did issue a Marginal risk for the southern panhandle as most of the convection seems to develop late, strengthen quickly but also move out of our CWA quickly as well. There are some embedded vort-maxes that will move with the shortwave but it's uncertain if the timing of the forcing will line up with our diurnal heating and moisture. The winds will be a little gusty and the RH values are forecasted to be below 15 percent so a fire weather watch was also issued for Carbon county Friday as well since their fuels were reported to be turned over already due to the lack of rain in that county. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 235 PM MDT Thu Jun 26 2025 Saturday...Zonal flow aloft continues. Another warm day expected with 700 mb temperatures near 15 Celsius, yielding high temperatures from the mid 80s to mid 90s. With a shortwave trough overhead, and low level convergence noted near the Wyoming and Nebraska state line, we anticipate isolated to scattered afternoon and evening showers and thunderstorms along and east of I-25. Sunday...Somewhat cooler temperatures in the wake of a cold front and with an increase in cloud cover. Looks like adequate low and mid level moisture for scattered late day showers and thunderstorms, mainly east of I-25. Monday...Temperatures about the same as on Sunday, with low level upslope east winds and 700 mb temperatures near 11 Celsius. Despite adequate low and mid level moisture, we may see a decrease in coverage of showers and thunderstorms due to ridging aloft. Tuesday...A warming trend develops as 700 mb temperatures rise to near 13 Celsius. Adequate moisture aloft for isolated to scattered late day showers and thunderstorms, mainly east of I-25. Wednesday...The warming trend continues as 700 mb temperatures reach 14 Celsius. Moisture looks a bit more prevalent than Tuesday, thus we should see an increase in convective coverage, including west of I-25. Thursday...Similar temperatures to Wednesday with 700 mb temperatures near 14 Celsius. Adequate low and mid level moisture again, thus scattered late day showers and thunderstorms expected.&& .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1127 AM MDT Thu Jun 26 2025 VFR conditions expected over the next 24 hours. FEW to SCT clouds at mid levels expected this afternoon, and should begin clearing overnight. Some precipitation may form off of the high terrain this afternoon and most eastwards, most likely impacting KLAR and KCYS. Some of these showers could make their way over to the Nebraska Panhandle, but probabilities are too low to include in TAFs at this time. Any showers or possible thunderstorms that do impact sites could briefly lower visibilities and CIGs. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Fire Weather Watch Friday afternoon for WYZ421>423-425-427. NE...None. && $$ SHORT TERM...MM LONG TERM...RUBIN AVIATION...CG