textproduct: Cheyenne

KEY MESSAGES

- Breezy conditions are expected today, though high winds do not look likely during morning and afternoon hours.

- A High Wind Watch is in effect for Bordeaux, the I-80 Summit, and the Foothills from 8PM tonight through 8AM Monday morning.

- Elevated fire weather conditions are expected on Sunday and Monday over the High Plains.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 204 AM MST Sun Feb 1 2026

Mild weather will continue Sunday as an upper-level ridge slowly moves into the region throughout the day. With largely subsidence present across the region under the ridge, clearing skies and warming temperatures are expected today, with highs in the upper-40s to upper-50s area-wide. As of 09Z this morning, a weak 700mb shortwave is pushing across western portions of the CWA, leading to breezy conditions ongoing across many locations west of the Laramie Range and the Bordeaux wind prone zones. These breezy conditions will continue through the morning hours as surface pressure gradients increase across the Arlington and Bordeaux wind prone zones due to a surface high strengthening in western Colorado. Synoptic subsidence today is modest, with GFS Omega fields suggesting decent downward omega values this morning. However, the 700mb jet remains fairly week, despite the shortwave passing through, remaining around 30 to 35kts. In house random forest guidance is also not overly excited about the winds this morning, so decided to keep them elevated but not in high wind territory. Therefore, breezy conditions expected throughout the day with many gusts between 40 and 50 mph possible, but high winds 58+mph are not expected at this time.

Strong winds look to return to the wind prone zones late Sunday night into early Monday morning as the upper-level ridge begins to break down into more zonal flow with an upper-level low pushing into the northern CONUS from southern Canada. An attendant shortwave trough is expected to move through aloft throughout the day Monday, further increasing concerns for gusty winds. Dry conditions from downsloping today and early Monday morning look to prevent any precipitation chances that this upper-level shortwave could have brought to the region. However, the winds do look to pick up, especially along the I-25 corridor and I-80 Summit areas. Northwesterly flow at 700mb is expected late tonight into early Monday morning, continuing throughout the day. A subtle, 700mb shortwave trough looks to push southeast just to the northeast of the CWA, placing the wind prones in a favorable location for increasing high wind chances. In fact, a 700mb jet around 50kts is expected to develop across the Laramie Range and points south. With GFS Omega values favoring strong downward motion, these 700mb winds look to mix down to the surface in the Bordeaux wind prone, as well as the I-80 Summit and Foothills. Surface pressure gradients across the Laramie Range increase to around 3-4mb early Monday morning, with 3mb gradients across the Arlington wind prone zone. With a strong jet, good subsidence, and strong surface pressure gradients, high wind chances look likely on Monday morning. In-house guidance suggests around a 40% chance for high winds at Bordeaux and the I-80 Summit and Foothills area. In-house guidance is not excited about Arlington, keeping it around a 25% chance for elevated winds. Craig to Casper gradients are also weaker than would be expected for high winds at Arlington. Given current forest data, decided to issue a High Wind Watch from 8PM tonight through 8AM Monday morning. These Watches may need to upgraded later this morning, if incoming model data continues to suggest high winds. However, Arlington should also be monitored, but confidence is too low right now to put out high wind headlines for this location.

Downsloping winds combined with warmer than average temperatures are increasing the risk for fire weather across the CWA, especially east of the Laramie Range. With winds likely gusting between 25 and 35 mph today and afternoon relative humidity values dropping into the 20 to 30% range, elevated fire weather is expected today. Similarly, downsloping winds and warmer than average temperatures persist into Monday, leading to another round of elevated fire weather conditions. Afternoon minimum relative humidity values look to drop into the 20 to 30% range once again Monday afternoon. Combined with winds gusting 40 to 50 mph in most locations, and potentially 60+ mph in the wind prones, elevated fire weather concerns persist into Monday afternoon. No fire weather headlines were issued at this time due to above criteria relative humidity values and low confidence in a three hour period of near-criteria relative humidity values.

LONG TERM /TUESDAY THROUGH SATURDAY/

Issued at 204 AM MST Sun Feb 1 2026

No major changes, see previous discussion below...

Long term remains exceptionally quiet as high pressure ridging dominates the Western US, keeping most systems outside of our forecast area and bringing unseasonable warmth. The long term starts on Monday with breezy conditions and perhaps a quick passing mountain snow shower overnight into Tuesday afternoon, but models have dialed impacts back notably. In house guidance only shows a 25- 40% probability for high winds at our wind prone locations for this day, and precipitation chances have all but evaporated in the NBM. Behind this system our temperatures "cool", but highs still remain 5 to 10 degrees above normal. And this will only get worse as the ridge builds over the Western US and overtakes our area through the end of the long term, as highs skyrocket on Thursday into the 50's to the 60's, with a few temperatures even flirting with near record warmth. NBM has kept our temperatures just under these records, but if trends continue don't be surprised if locations including Cheyenne itself begin to approach notable warmth. This high will also act as a shield, keeping passing systems just outside of the area, bringing precipitation chances to zero and winds below warning criteria, with ensembles and in house guidance in solid agreement on our quiet warmth to end the long term. The ridge will also start to elongate by the end of the long term which keeps temperatures a few degrees cooler on Friday, but still significantly warmer than average. While the Eastern US continues to freeze, winter is but a fleeting memory for our neck of the woods in the upcoming forecast.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 405 AM MST Sun Feb 1 2026

VFR conditions expected through the 12Z TAF period with increasing cloud cover through the day. Low-level wind shear may be present near KCYS this morning, prior to surface winds picking up by 15Z. All Wyoming terminals will gust between 20 and 30 kts today, while the Nebraska terminals keep relatively calm winds.

CYS WATCHES/WARNINGS/ADVISORIES

WY...High Wind Watch from this evening through Monday morning for WYZ106-116-117. NE...None.