textproduct: Cheyenne

KEY MESSAGES

- A Red Flag Warning is in effect for all areas along and east of the Laramie Range through Saturday evening. Hazardous fire weather conditions expected.

- Record warmth will continue this afternoon through Saturday.

- Cooler, though still above average, temperatures return Sunday behind a cold front pushing through. Isolated to scattered precipitation chances expected with this frontal passage.

SHORT TERM /THROUGH SATURDAY/

Issued at 230 AM MDT Thu Mar 19 2026

Current observations across the region show an unseasonably mild night with temperature readings generally in the mid to upper 40s to mid 50s. These temperatures are roughly 20 to 30 degrees above average mid-March low temperatures, which is pretty impressive. Already hit some new record high temperatures on Wednesday and expect that to continue for Thursday, Friday, and especially Saturday.

00z models show the dominant 595dm upper level high sitting over Arizona and southern California today. 500mb high this strong is more typical of June or July, with models showing 500mb heights between 2 to 4 standard deviations above the mean for this time of the year. Not only that, but this feature remains near the four corners region through Saturday with the northern ridge axis extending northward into Wyoming Friday and Saturday. Not a big surprise that NAEFS shows geopotential heights and layer temperatures above the 99th percentile and into the all-time- high category at all levels between the surface and 500mb through the end of the week and into Saturday. With that said, confidence is very high that nearly all climate locations will see record high temperatures. Some locations may not only see all time March record highs, but possibly closing in on all time April high temperatures as well! The warmest day is forecast to be on Saturday where nearly all of the high plains will see afternoon high temperatures in the mid 80s to low 90s. May even see a few locations push 93 to 95 degrees for the first full day of Spring. Did not go quite that high since ensemble guidance is already pushing 95th to 99th percentile for high temperatures around 90 for the day for western Nebraska. Even across the high valleys of central Wyoming, high temperatures in the upper 70s to near 80 are forecast Saturday afternoon. There is a chance some cloud cover may interfere with deep boundary layer mixing, but temperatures will already start out warm Saturday morning. Outside of fire weather concerns, minimal to no impacts expected with pleasant weather.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

Issued at 149 PM MDT Wed Mar 18 2026

A shortwave trough passing well to the north of our area will flatten the powerful ridge over the weekend. The upper level system will be followed by a surface high pressure system sliding down into the northern Plains, which will push a cold front through the area Saturday night. While temperatures are expected to drop 20 to 30 degrees from Saturday's highs, Sunday's forecast high is still slightly above average for much of the area, emphasizing the magnitude of this week's warm air event. About 50% of ensemble members have some light rain and snow showers moving through the area with the frontal passage, but this is not expected to provide appreciable rainfall.

The ridge begins to re-strengthen across the western CONUS by early next week, sending temperatures back to values well above average by the end of the forecast period. The second round of warmth should peak around Wednesday of next week, before ensembles diverge wildly beyond. We will also need to watch for the threat for high winds potentially returning around Tuesday of next week. Probabilities are not too high right now, generally around 40%, but with the second phase of this warm spell looking like a little more zonal flow, we will need to watch for winds aloft increasing as it gets closer. NAEFS mean 700-mb winds indeed approach the 90th percentile by the end of the day on Tuesday. Record highs may also creep back into the forecast during this period as 700-mb temperatures push back above the 90th percentile and even close to the 99th percentile on Tuesday into Wednesday.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1131 AM MDT Thu Mar 19 2026

VFR conditions expected at all terminals today. Some gusty conditions are occurring at KRWL, KLAR, and KCYS where gusts to 30 to 35 knots out of the west/northwest are possible until 00z this evening. For West Nebraska terminals winds out of the northwest and gusts to 20 knots are possible until 00z when they fall to around 10 knots.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning until 8 PM MDT Saturday for WYZ417>423-425- 427>433. NE...Red Flag Warning until 8 PM MDT Saturday for NEZ434>437.