textproduct: Cheyenne

KEY MESSAGES

- Dry conditions and above average temperatures will continue into the next week.

- Fire weather concerns will increase on Monday alongside a chance at record high temperatures.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 221 AM MDT Sun Oct 4 2026

A pleasant end to the weekend is expected with sunny skies and mild temperatures. With the bubble of high pressure strengthening over the Four Corners region, slightly warmer temperatures are forecast for Sunday. 700 mb temperatures will climb to over +10C, leading to above average highs in the upper 70s and 80s. Subsidence under the high pressure bubble will lead to sunny skies and no chance of precipitation on Sunday.

Heading into the start of the work week, warmer and drier conditions are expected. Although the ridge over the Four Corners will begin to weaken, 700 mb temperatures will continue to rise. 700 mb temperatures will warm above +12C, which is above the 99th percentile for NAEFS climatology. The anomalously warm air aloft will lead to a hot fall day on Monday, with highs in the upper 70s to upper 80s. A few lower elevation locations may even reach the low 90s. As a result, a few locations are likely to break record highs. Records will most likely be broken in southeast Wyoming, however it is possible that a few Nebraska locations will be within a degree or two of current records. With the ridge weakening, winds will turn more westerly, leading to breezy conditions across southeast Wyoming during the afternoon hours. Westerly winds will cause downsloping and dry conditions, leading to critical fire weather conditions. With no precipitation chances in sight, Fire Weather Watches are already in place for Monday afternoon for portions of southeast Wyoming. Winds will ease Monday night after sunset, however overnight humidity recoveries are still expected to be poor.

LONG TERM /TUESDAY THROUGH SATURDAY/

Issued at 115 PM MDT Sat Oct 3 2026

On Tuesday a diffused upper level trough makes its way into the Four Corners region. This feature would flatten the upper level ridge that has been parked over the area the last few days. The trough would also bring an uptick in moisture, perhaps enough to kick off a few showers and storms over higher elevations. Even with the weakened ridge, our flow is still primarily out of the northwest and the surface will remain dry and warm. Afternoon high temperatures are likely to be in the low to mid 80s north and east of I-25. Mid to high 70s possible west. Relative humidity values in the teens could promote elevated fire weather conditions. Thankfully winds are not expected to be particular strong and overnight recoveries are fair.

Wednesday through Saturday is a rather uneventful stretch from a meteorological perspective. Afternoon highs stay above average in the high 70s to mid 80s. Mostly clear skies are expected. There are no clear signals in model guidance for an appreciable disturbance, just weak zonal flow on the north end of a weak upper level ridge. We may have to wait until next weekend for a chance of a disturbance in this stagnant pattern.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 512 AM MDT Sun Oct 4 2026

VFR conditions will prevail for the TAF period. Mostly sunny skies with typical diurnal winds are expected throughout the day. Little to no aviation impacts are anticipated.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Fire Weather Watch Monday afternoon for WYZ418>422-427-430-432. NE...None.