textproduct: Western and Central Wyoming

KEY MESSAGES

- Mostly sunny and warm conditions continue today, with highs in the upper 60s and lower 70s.

- A weak frontal boundary sweeps across areas east of the Divide on Sunday, bringing a low chance of showers and thunderstorms (20 to 30%) mainly to higher elevations.

- The next weather system moves across the state Monday and Tuesday, bringing a better opportunity for showers.

DISCUSSION

Issued at 139 AM MDT Sat May 2 2026

A great start to May continues today with high pressure in the region. Skies remain mostly sunny, with only a few high clouds moving in from the west during the afternoon. With the ridge axis pretty much overhead today, temperatures again will be warm for early May, reaching the mid to upper 60s west of the Divide, and the low to mid 70s to the east.

Conditions begin to change late tonight into Sunday as the ridge gets squashed southward. This will open the door initially for a weak frontal boundary to move in from the north Sunday morning. While this front won't have an appreciable temperature difference with the ridge still in the vicinity, there will be a marked increase in moisture, noted by dew point increases of 10 degrees and precipitable water (PW) values rising from 0.20 to roughly 0.45 by sunrise Sunday. This increased moisture, along with increasing instability aloft, will bring a chance for showers and thunderstorms, mainly across the higher elevations of northern WY, including YNP, during the peak heating hours Sunday afternoon.

Monday and Tuesday will be influenced by a broad trough to the northeast bringing a long fetch of northerly flow. This will help push the front farther south across the rest of the state. The trough will also draw in energy from a cutoff low drifting across southern California, bringing in more moisture and instability across the state. Most of the precipitation expected with this system still looks to be an overrunning pattern behind the front. Still watching models to see where the front finally settles, which will determine which areas to the north of the front will be the focus of precip Monday night into Tuesday. Models have been fairly consistent in the amounts that will be produced (0.25 to 0.50"), it's just getting the final placement set.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 403 AM MDT Sat May 2 2026

VFR conditions will continue through 12Z Sunday with only passing areas of mid to high level clouds. Some cumulus development will be possible this afternoon, mainly in the mountains and across northern Wyoming. Wind should remain largely light through the period, although some gusts to 15 to 20 knots will be possible in vicinity of KRKS, KCPR and KCOD at times. Chances for showers return after 12Z Sunday.

RIW WATCHES/WARNINGS/ADVISORIES

None.