textproduct: Western and Central Wyoming

KEY MESSAGES

- Red Flag Warnings continue today and Monday thanks to above average high temperatures, gusty wind, and very dry conditions.

- A weather system moves in on Monday, with a strong cold front pushing through Monday evening into Monday night. Most precipitation will be confined to higher elevations in the form of snow. Some lower elevation locations may see up to a tenth of an inch of rain.

- It will remain cooler, with chances for precipitation Tuesday and beyond thanks to a weather pattern change. Chances for lower elevation location to receive a tenth of an inch of rain increase for Thursday and Friday.

UPDATE

Issued at 1230 PM MDT Sun Mar 29 2026

No significant changes or updates to the forecast as critical fire weather continues this afternoon and into Monday. Wind forecast continues to point to Monday as the gustiest afternoon and evening ahead of an approaching cold front. The slight decrease in winds for Johnson County Monday afternoon has backed the other way, but regardless windy conditions will exist meeting red flag criteria ahead of FROPA. Timing of FROPA has slowed a bit more with many 12Z model data. Deterministic data have differences in only up to 2 to 3 hours pushing further towards 06Z Monday night. As such, near record temperatures Monday afternoon will still hold at all locations. Beyond that, QPF amounts have trended a bit lower as per usual the closer to an event one gets, especially during this winter and early spring. A wetting rain for much of the CWA looks to have better chances come Tuesday night into Wednesday and Thursday, especially east of the Divide. Stay tuned for updated forecasts in the next couple of days. Until then, enjoy the warmth but burning of any kind is highly discouraged today and tomorrow.

DISCUSSION

Issued at 150 AM MDT Sun Mar 29 2026

A broad flat ridge remains in place over the region this morning, leading to another day of dry conditions with above normal temperatures and gusty winds. West to southwest winds, with gusts of 25 to 35 mph, will be more widespread across the CWA this afternoon. High clouds will remain over the area, but are not expected to be as thick as they were Saturday and hampering any afternoon mixing from occurring. Northern Johnson County looks to be the one location in the CWA whose winds will stay below 20 mph this afternoon. Most locations are forecasted to either set new record high temperatures or tie this afternoon.

Dry conditions continue into Monday, with winds increasing across the CWA as a trough and associated cold front approach from the northwest. Areas east of the Divide have a 70-90% chance of gusts over 50 mph and a 25-50% chance of gusts over 60 mph. Although the chances for the latter have gone down with this latest forecast, I do not see much support for this happening. 700mb winds have come down slightly in both the NAM and GFS guidance, with 30-45kt winds occurring across the CWA and 50kt winds very sporadic Monday afternoon. The previous thinking of gusts of 60 mph is the same, where they would likely occur late in the afternoon between 22Z (4PM) and 00Z (6PM) with peak heating and the proximity of the front being the major contributors. Otherwise, chances for precipitation will increase over northwestern portions through the day Monday, with snow levels between 7500ft and 8500ft. Although the timing of the front has slowed down during the day Monday, it will quickly progress southward through the overnight hours. However, the coldest air (700mb temps of minus 7C to minus 10C) will lag behind the front and stay confined to northern portions by 12Z Tuesday. Cody and Buffalo have the greatest chances for snow in the lower elevations as a result, with amounts ranging between 1 and 2 inches. Any snow that occurs in the Wind River Basin and Natrona County is expected to remain confined to mostly grassy surfaces as the coldest temperatures to support snow in these areas look to arrive around 12Z Tuesday. Any snow that falls will begin to succumb to the late March sun angle through the morning after sunrise. Otherwise, forecasted amounts of 2 to 5 inches in the western and northern mountains remains unchanged.

Models sped up the timing of a shortwave trough moving onshore and over the Great Basin Tuesday, spreading Pacific moisture over the Cowboy State. Additionally, there will be weak cyclonic flow over the region in the wake of Monday night's storm system. This will result in a 30% chance for showers over the southern half of the forecast area, including the Jackson Valley. There looks to be enough instability during the afternoon for a thunderstorm or two across portions of Sweetwater, Sublette and southern Lincoln counties.

Chances for precipitation will continue Wednesday as this shortwave exits over the Central Plains and a difluent flow pattern develops over western portions ahead of the next digging longwave trough. Models remain in alignment, with both the ECMWF and GFS progging a closed low moving over the PACNW Thursday and over the Cowboy State Friday. Precipitation chances over western portions begin to increase Wednesday afternoon as divergence aloft develops as the low digs and moves onshore over the PACNW. Precipitation chances spread eastward through the day Thursday and remain relatively high Friday as the low moves over the Black Hills region by 00Z Saturday. Western portions are most likely to receive a wetting rain (liquid precip amounts of 0.10" or more) from this storm, with areas east of the Divide having a 40-70% chance for Thursday and Friday; southern portions will have a 35-55% chance. This also looks like this could be a good snow event for the far western mountains from Wednesday into Friday, as snow levels will be around 7500 to 8000ft before the main low moves through on Friday.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1104 AM MDT Sun Mar 29 2026

VFR conditions through the period, with passing high, cirrus clouds at times. Widespread gusty west winds this afternoon, generally 20 to 30 knots, though some occasional stronger gusts are possible. Winds decrease this evening. Stronger winds are expected Monday, with winds beginning to increase near the end of the period.

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

FIRE WEATHER

Issued at 150 AM MDT Sun Mar 29 2026

Critical fire weather conditions continue today and last through Monday. West to southwest winds with gusts of 30 to 35 mph will occur for much of the forecast area this afternoon, except for northern portions of zone 281. RH recovery will be fair to poor again tonight. Precipitation chances will be confined to far northwestern portions of the state during the day Monday, with snow levels around 7500ft to 8500ft. The front will move through the area Monday night into Tuesday morning with snowfall amounts of 1 to 2 inches expected near Cody and Buffalo. Chances for a wetting rain elsewhere east of the Divide are very low.

RIW WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 9 PM MDT Monday for WYZ275>283-285-287- 289-300.