textproduct: Western and Central Wyoming

KEY MESSAGES

- Cool and clear tonight with near normal low temperatures.

- A weak weather system may bring cooler temperatures Thursday and Friday and isolated showers to northern Wyoming.

- Mainly dry conditions and unseasonably warm temperatures will dominate for most of this weekend and into next week.

UPDATE

Issued at 1129 AM MDT Wed Sep 30 2026

Not much to update regarding the forecast as there has been little to no change compared to the previous discussion. Pleasant, dry, and warm conditions are expected across the Cowboy State today. Highs may get into the low 80s across the Bighorn Basin while most locations see high temperatures in the mid to upper 70s. Conditions look to remain dry through the remainder of the week with warm temperatures returning by Friday through the start of next week. There are early indications of unseasonable warmth with temperatures nearly 10 to 15 degrees above normal by the end of the weekend into the start of next week. Current model guidance is showing a 40-70% chance of highs reaching or exceeding 80F across most locations east of the Divide on Monday. There is still time for things to change but at this time there is fairly good consensus among models. That being said, it is looking like the first week of October is going to start off quite warm, which is not much of a surprise when you look back at how the past 9 months have been.

DISCUSSION

Issued at 1250 AM MDT Wed Sep 30 2026

We have now reached the end of the ninth month of the year, about 75 percent through the year (74.5 percent to be exact). And we are now in, as a rule, on of the nicest times of year in Wyoming. This generally runs from after Labor Day through the middle of October. Yes, I realize we have had some snowstorms, and some substantial ones during this time frame, but most days are nice. And most of the next several days will be no exception.

For most of the area today, the weather will be described by a couple of songs popular around the turn of the millennium. The better known one is by U2, the lesser known one, at least on this side of the Atlantic, is by the British band 3 Colours Red. And those songs are "Beautiful Day" and "A Beautiful Day", respectively. Today will feature a cool morning, a comfortably warm afternoon and a good deal of sunshine. As for cloud cover, the most would be across the far north, and in southern Wyoming, where some high level moisture may move up from the remnants of Hurricane Polo. However, showers will remain to the south and east of our area. It could become breezy late today across portions of northern Wyoming, but nothing by Wyoming standards. So, if you can, get out and enjoy it.

A weak cold front will make a run at Wyoming Thursday into Thursday night. Impacts from it look minimal at this time. Guidance has trended further north with the jet forcing than at this time yesterday. The front also is of continental origin and has little moisture to work with. As a result, the chance of showers Thursday into Thursday night has also dropped. There is still a small chance of shower Thursday night, but it is 1 out of 6 at the most and largely limited to north of a Lovell to Buffalo line. The main impact we will be somewhat breezier conditions and a small reduction in temperatures, but only 5 to 10 degrees with the biggest drop in the northern Bighorn Basin and Johnson County.

Friday at this point looks like a mild and quiet day. Another cold front will make a run at northern Wyoming Friday night into Saturday. However, the same criteria applies to this front as the last one. The chance of showers is minimal and largely restricted to far northeastern portions of the area. Again, the main impacts will be for somewhat cooler temperatures East of the Divide and breezy conditions in the favored cold advection locations like the northern Big Horn Basin and Johnson County.

In the longer term, ridging will set up across much of the western United States and bring a period of mainly dry conditions and above normal temperatures from Sunday through much of next week. There will be another fast moving system moving west to east into the area Monday night into Tuesday. It could bring some showers during this time frame. The main impact may be some increasing wind ahead of it. This, combined with low humidity and unseasonably warm temperatures, may bring elevated fire weather Monday afternoon to portions of the area. Otherwise, things look relatively uneventful next week with some, shall I say, beautiful days a very good possibility.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 345 PM MDT Wed Sep 30 2026

VFR conditions expected throughout the entire period at all TAF sites. Light winds and mainly clear skies overnight with radiational cooling. This continues through Thursday afternoon, outside of a slight breeze up to 18kts at RKS after 18Z with daytime heating and mixing to the surface. No other weather elements expected at this time.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on smoke, icing, and turbulence forecasts.

RIW WATCHES/WARNINGS/ADVISORIES

None.