941 FXUS65 KCYS 052342 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 542 PM MDT Fri Jun 5 2026 .KEY MESSAGES... - Near record high temperatures and elevated to critical fire weather conditions are anticipated this weekend. - Expect a quick cool down on Monday before heat builds back into the area towards the middle of next week. - There is potential for widespread critical fire weather conditions on Tuesday and Wednesday. && .SHORT TERM /THROUGH SUNDAY NIGHT/... Issued at 216 PM MDT Fri Jun 5 2026 Currently a beautiful afternoon across the forecast area after multiple days of severe weather. Visible satellite imagery shows a mostly sunny day with some fair weather cumulus along and and east of the Laramie Range. Precipitation is not expected today as dry air settles into the region. Temperatures range from the 70s to the 80s and will continue to get warmer as the afternoon progresses. Although it is a bit on the warmer side, a light breeze will help keep the air from feeling stagnant. Quiet conditions will continue into the overnight hours with mild low temperatures expected. Upper-level ridging will begin to amplify over the center of the country on Saturday, placing the CWA in southwest flow aloft. Southwest flow will usher in hot and dry desert air, leading to near- record high temperatures over the weekend. 700 mb temperatures will climb to +16C, which is around the 97.5th percentile for NAEFS climatology. The anomalously warm temperatures aloft will lead to surface temperatures potentially reaching the triple digits on both Saturday and Sunday. Hottest temperatures are expected in the Nebraska panhandle and the North Platte River Valley. Cheyenne and areas west of the Laramie Range can expect temperatures in the upper 80s. On top of the heat, it will be very dry with mid-level relative humidity around 25 to 35 percent. Surface relative humidity will be even lower, with some locations falling into the single digits. Windy conditions at the surface Saturday and Sunday will add to the dryness. The CWA will sit at the eastern periphery of a 250 mb jet, leading to wind gusts of 30 to 40 MPH each afternoon. All these conditions will combine to create critical fire weather conditions. A Fire Weather Watch is in effect Saturday for the Nebraska panhandle and far southeast Wyoming where fuels are deemed critical. Fuels across the rest of southeast Wyoming are still in green-up and thus not ready to burn. Despite this, critical fire weather conditions are still forecast for the weekend. Saturday will also feature a weak disturbance aloft that moves across the Rockies. Even though the low and mid-level will be extremely dry, this disturbance will spark some convective development across the area. At this point, the HRRR shows nothing more than some gusty showers across the area. With model soundings showing over 1500 J/kg of DCAPE, severe winds gusts are possible in these showers. Soundings also show a lot of elevated convection across the Nebraska panhandle during the afternoon on Saturday. This could lead to a few isolated thunderstorms. These thunderstorms could produce dry lightning across the area given how dry the lower part of the atmosphere is. The area will once again face potential storm chances on Sunday. A trough that will pass the CWA to the north will send a cold front through the area Sunday evening. Some models hint that the eastern portion of the CWA could see some precipitation from this, albeit not that much. There are a few CAMs that hint at thunderstorms developing in the panhandle with 1500 J/kg of CAPE, while soundings from the GFS around the same time are less than impressive, not even hinting at any convective potential. Regardless, there is still time to iron out the Sunday afternoon and evening forecast as Hi-Res guidance has the chance to catch on to this system. && .LONG TERM /MONDAY THROUGH FRIDAY/... Issued at 216 PM MDT Fri Jun 5 2026 A brief reprieve from the summertime heat is on order Monday as a strong shortwave brushes and a surface cool front drags through the forecast area. Temperatures will remain seasonable to warm however, with most locations east of I-25 still reaching the lower to mid 80s. Despite the increased forcing with the wave and front, moisture will be hard to come by. Can't rule out a few pop-up storms, mainly near the ranges and in the panhandle, but most spots will stay dry. The large upper ridge centered over the Great Lakes reamplifies heading into midweek, setting the stage for another round of near record heat for eastern Wyo and western Neb on Tuesday. The middle of the NBM envelope suggests highs around 90F at CYS and upper 90s for BFF/CDR. The next upper low spins into the northern Rockies Wednesday and beyond, switching southwesterly flow aloft to northwesterly. Temperatures should gradually back off to more seasonable levels by late next week. In the meantime, fire weather conditions will definitely need to be monitored. The pattern is the epitome of "dry heat" as humidity levels drop into the lower teens Tue-Thu. Coupled with rounds of gustier winds (30+ kts), limited precipitation potential, and continued D2-D4 drought across the region, additional Red Flag conditions may be realized. The strongest winds appear to be Wednesday with a tight surface pressure gradient in place, and Thursday as the core of the upper jet lines up with the forecast area. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 524 PM MDT Fri Jun 5 2026 Mostly clear skies over most terminals this evening, with scattered cumulus at 10 to 8 kft lingering near the Nebraska Panhandle terminals. Overnight a low level jet develops over the high plains bringing in a shallow moisture rich airmass and gusty southeastern winds. Wind gusts to 30 knots are possible. As this jet subsides, some low lying terminals in the Panhandle may cool enough for fog. The greatest likelihood of this occurring is at KSNY, however coverage may extend to KBFF and KAIA. Otherwise, ceilings to 1000 feet or below are possible which may send terminals in the Panhandle to IFR or LIFR. Most of the fog and low stratus deck lifts and burns off by 15z giving way to mostly clear skies. During the afternoon elevated convection is anticipated to develop. Dry microburst and erratic winds are possible at all terminals. Winds to 45 kts or greater are a slight possibility, however given the very scattered nature of this activity, only vicinity showers were included in some terminal TAFs. Lightning risk seems low but not zero. A more substantial isolated thunderstorm or two may develop in the Nebraska Panhandle at the end of the forecast period, but again probabilities are too low to include in this forecast. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Fire Weather Watch from Saturday afternoon through Saturday evening for WYZ430>433. NE...Fire Weather Watch from Saturday afternoon through Saturday evening for NEZ434>437. && $$ SHORT TERM...SF LONG TERM...DS AVIATION...RV