883 FXUS65 KCYS 060709 AFDCYS Area Forecast Discussion National Weather Service Cheyenne WY 109 AM MDT Sat Jun 6 2026 .KEY MESSAGES... - Near record high temperatures and elevated to critical fire weather conditions are anticipated this weekend. - A Marginal Risk (1/5) of severe weather with a small area of Slight Risk (2/5) is expected on Sunday for east-central Wyoming and the Nebraska Panhandle, with gusty winds and large hail the main threats. - 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 107 AM MDT Sat Jun 6 2026 A ridge of high pressure will begin building over the Central US with a weak low over the Central Plains and a deep trough and low over the West Coast through the weekend. A small and weak shortwave should pass across our region today with a much stronger shortwave grazing the CWA but mostly impacting further north into Montana on Sunday. With this pattern, look for southwesterly flow which will bring warm and dry desert southwest air, with high temperatures rocketing into the 80's to 90's for west of the Laramie Range, and upper 80's to triple digits for locations east of the Laramie Range. Some of these highs will near records for the day. Meanwhile the enhanced pressure gradient from these systems will bring strong and gusty winds, with stronger southerly winds for the Nebraska Panhandle and far eastern Wyoming on Saturday, and then much stronger winds west of the Laramie Range on Sunday. These winds alongside very dry surface conditions will promote critical fire weather danger across much of the area. While western zones remain in greenup and fuels are not critical, our fuels status remains critical for the southeastern corner of Wyoming and the Nebraska Panhandle, and a Red Flag Warning was issued for today because of this. To further enhance this danger, the weak shortwave on Saturday could produce some elevated convection that will struggle to produce rainfall at the surface, creating gusty virga showers with locally strong winds, and even the potential for dry lightning. Moving into Sunday, our concern becomes severe weather once again, though the bulk of most strong activity should remain just north of our region. That being said, a Marginal Risk (1/5) is expected for our northern zones, primarily Converse and Niobrara Counties into the northern Nebraska Panhandle, with a Slight Risk (2/5) just barely clipping the two aforementioned Wyoming Counties. The surface cold front will pretty quickly overtake the surface low and dryline on Sunday, with high resolution guidance going with a few stronger storms during the afternoon and into the evening for the northern extent of our CWA, but as mentioned the better ingredients for severe lie too far north and keep our timing low for stronger to severe activity. Still, some meager instability around 500-800 J/kg will be present alongside pockets of favorable Helicity, so a few storms capable of baseline severe hail and strong wind gusts will be possible. Don't be surprised as well if a few sub-severe storms are able to form further south of the severe risk, and modest DCAPE may help promote some stronger gusts with this activity. && .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 1053 PM MDT Fri Jun 5 2026 A low level jet has developed over the high plains in response to troughing to the north. KCDR may experience wind gusts to 25 knots with higher gusts possible from this jet. This jet has also transported a shallow moist layer north into areas of the Nebraska Panhandle. Given the near saturated surface air, patchy fog or a layer of low stratus, with CIGs down to 500 feet, are likely to develop here. KSNY appears to have the greatest chances of experiencing fog, though high resolution model guidance has been less supportive of this solution. Given the over achieving dew points being observed this evening, fog was kept in the TAF here. KAIA and KBFF could experience a low stratus deck which may briefly send it into MVFR or IFR conditions, though fog may also develop at these terminals. Around sunrise the winds are expected to pick up and lift this stratus deck before it disperses. In the afternoon high based convection is expected. High resolution models have been a little more aggressive with coverage and intensity of this convection the last few runs. While probabilities are still below 30, too low to include in any terminal TAF, the impacts of these showers are likely to impart strong and erratic winds to regional terminals. Some wind gusts could exceed 50 knots. An isolated thunderstorm or two is definitely a possibility as well. Winds outside of those convectively influenced will be out of the south or southeast for all terminals at 15 to 20 knots. Saturday night another low level jet is likely to form with gusts reaching 35 knots at the high plains terminals. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Red Flag Warning from noon today to 9 PM MDT this evening for WYZ430>433. NE...Red Flag Warning from noon today to 9 PM MDT this evening for NEZ434>437. && $$ SHORT TERM...CG LONG TERM...DS AVIATION...RV