textproduct: Cheyenne

KEY MESSAGES

- A High Wind Warning in effect until 3 PM for Carbon County and a very small portion of Albany County.

- Above average highs this afternoon, but a cold front will drop temperatures to around 5 to 10 degrees below normal for the weekend. - Near normal temperatures and a bit warmer by Tuesday into Wednesday, but next Pacific system will be approaching from the Pacific Northwest by the middle of the week.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 215 PM MDT Fri Oct 23 2026

This weekend split flow will continue to decline our precipitation chances as moisture gets pushed just to our east. The pattern through the forecast period will consist of the split in flow as upper level troughing lifts up and combines with Canadian troughing, with a very quick transient ridge building over the area on Saturday, but the other half of the split flow in the form of a cutoff low will be moving into the Four Corners, becoming the focal point for our forecast through Monday evening. At the surface, a cold front moves across this evening and should fully pass through our region by Saturday morning, with some high pressure overtaking in its wake but multiple shortwaves passing across through the weekend.

Under this pattern, we'll see a quick chance of precipitation this evening along the trough axis and a weak boundary setting up across the Nebraska Panhandle and draping down through Laramie County. Have included some shower chances across this area, but expected those to be isolated to possibly scattered with minimal QPF accumulations. This flow is also struggling to show meaningful precipitation in the high terrain as the jet weakens this afternoon and evening and flow begins to lower in response, and CAMs are not indicating we'll see anything meaningful in this region alongside NBM guidance. The next noteworthy batch of precipitation is expected Saturday evening into Sunday under southerly to southwesterly flow as moisture begins to return, and continues through Sunday night into Monday. The issue will be the fact that the bulk of this moisture gets pushed to our east, and without a strong forcing mechanism over the area we'll struggle to get much more than scattered weak showers through this period. Latest QPF analysis shows only widespread precipitation totals in the 0.1-0.2 inch range, with Cheyenne County expected to be the "big winner" as this area will be closest to the better moisture in Central Nebraska with totals nearing 0.3-0.5 inch. Accounting for bias correction, this could even be on the high side, but taking a look at ensembles, it appears that most guidance errs on the side of 0.1-0.4 inch widespread which would at least give the hope for some much needed moisture, but don't bank on a soaker. The bulk of this also falls either in the high terrain or east, so lower elevations in Carbon and Albany Counties may be sitting this one out.

Outside of precipitation, our cold front will bring notably cooler temperatures as highs sit around 5 to 10 degrees below normal on both Saturday and Sunday, with widespread highs in the 50's to 40's and overnight lows in the 30's. These near freezing to freezing conditions could even encourage some wintry precipitation to mix in with morning rain, but a few flurries and rain/snow mix are the most that is expected out of this currently. Finally, the gusty conditions we've seen today should persist through Saturday morning as the pressure gradients shift eastwards, but by the afternoon winds should be relaxing with relatively benign speeds for this region to conclude the weekend.

LONG TERM /MONDAY THROUGH FRIDAY/

Issued at 215 PM MDT Fri Oct 23 2026

Active weather will characterize the first few days of the long term period from Monday through Tuesday night. On Monday morning, weak surface troughing will extend from the New Mexico high plains northward through Colorado and western Nebraska. Seasonably high surface moisture will be in place with ensemble guidance supporting PWAT values on the order of 1-2 sigma. The center of a ridge of high pressure will be located in the northern high plains, resulting in broad easterly flow around its base including western Nebraska and eastern Wyoming. These factors combined will result in overcast conditions with numerous clouds and showers around throughout the day. Ensemble guidance is mixed as to liquid totals given a lack of a well- defined surface low over the high plains. This is currently resulting in a highly dispersive forecast with some guidance supporting a moderate to heavy rainfall event east of I-25 through the NE panhandle and another large group of ensemble members keeping this event less organized and farther east. Some forecast guidance members, particularly the operational ECMWF, indicate a potential overlap between cold temperatures in east- northeasterly flow and heavier QPF, enough to produce some light snowfall on the order of 1-3 inches for east-central Wyoming and the northern Nebraska panhandle. Currently, this outcome appears to be somewhat of an outlier compared to the rest of guidance. Overall, with weak forcing aloft and a lack of a more defined surface feature, we will favor the drier (and less snowy) end of the guidance package for the Monday timeframe. Still, abundant cloud cover and east-northeasterly flow should keep temperatures around 10 to 15 degrees cooler than average for Monday. This messy, disorganized system drifts east of the region on Monday night, with any lingering shower activity ending possibly as early as 6 to 9pm. After a partly cloudy overnight, attention quickly turns to our next system moving from the Great Basin into southwest Wyoming on Tuesday afternoon. Unlike the Monday event, this system will feature a potent mid/upper level low pressure center and faster wind speeds aloft. However, recent ensemble guidance trends continue to show very little precipitation making it to the ground outside of the mountains with this system as it translates eastward on Tuesday evening and overnight. In the Snowy, Sierra Madre, and northern Laramie ranges, current model QPF averages are around 0.1 to 0.2 inches of liquid. As this system exits eastward on Tuesday night, a fast jet stream in the 700-500mb layer is indicated by most guidance in an west-east orientation across southeast Wyoming. Given the favorable flow orientation, upper-level pattern and wind speeds aloft it is possible that a higher-wind event may be in the works for the Wednesday timeframe over the wind prone locations of southeast Wyoming. Dry zonal to north-westerly flow will resume over the region from Thursday through the end of the week with limited impacts expected.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 553 PM MDT Fri Oct 23 2026

There is a slight chance of a few showers and storms developing in the Nebraska panhandle this evening. However, storms should not pose much of an impact aside from gusty winds and potentially lightning. Winds will shift more northerly later tonight as a cold front moves across the area. Gusty winds are expected behind the front with gusts over 20 kts expected early Saturday morning. Cannot rule out brief MVFR CIGs with the frontal passage with HREF probability of low CIGs currently sitting at around 20 percent for KCYS, KLAR, KRWL, and KCDR. Winds will begin to weaken later in the day on Saturday, with increasing precipitation chances.

CYS WATCHES/WARNINGS/ADVISORIES

WY...None. NE...None.