textproduct: Cheyenne

KEY MESSAGES

- Winter Weather Advisories will be expiring this evening for our western zones as snow accumulation begins to decline.

- Another round of accumulating snow is expected Thursday afternoon through Saturday morning, with models beginning to come into agreement on snow potential through our entire CWA including locations east of the Laramie Range.

- The pattern will shift to mostly dry and above normal temperatures after Saturday and persist through the start of next week with high winds possible during this time as well.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 205 PM MST Tue Mar 3 2026

After yesterday's very active system brought much needed moisture and an early start to our spring thunderstorm activity, the trough that produced this activity is moving out of the region, with snow and light rain/snow mix expected to continue through this evening before fully departing. Winter Weather Advisories will continue through this evening before expiring, but some light accumulations can be expected through expiration and perhaps even right after. Light rain will also shift eastwards primarily across the I-80 corridor, and as temperatures drop may begin mixing with snow, but accumulations are not expected to be noteworthy. Meanwhile, the snow that has already accumulated has begun driving temperatures down west of the Laramie Range. Have pulled down highs and lows over the next day or so to account for this, but depending on how strong this snowpack is may need to adjust further in coming updates, particularly for tomorrow.

Moving into Wednesday and early Thursday, transient ridging will bring dry conditions alongside warming temperatures as highs rise back into the 50's and 60's east of the Laramie Range, while highs may remain in the 30's to 40's to the west. While some patchy spots of low RH values into the 20's and possibly high teens will be possible for our northeastern zones across Wyoming and Nebraska, winds should remain low and with recent precipitation, critical fire weather conditions will be unlikely.

But then Thursday during the late morning into early afternoon the next system expected to impact our area will begin moving into the region. We'll find the CWA under the left exit region of a low-level jet before the trough bringing this feature then forms into a cutoff Colorado low. Models are beginning to come into better agreement on this system and its impacts, with a widespread snowfall event now expected for our area through Saturday morning. Currently the mountains do get the bulk of the precipitation, with accumulations around 6-10 inches, but locally heavier amounts nearing a foot possible at the peaks and crests. Meanwhile the wrap around moisture and cooler temperatures should actually fuel snow for once east of the I-25 corridor, with a widespread 1-5 inches currently expected through the Nebraska Panhandle. Because model agreement is just starting to come together on this system, some fluctuations to these accumulations are possible, and if this low does slow down we could see amounts on the rise. For now, expectations are that we'll need winter products for much of the area, but a few warning level products may be possible as well depending on how this evolves. And with this colder shot of air, we'll actually see highs below normal for once as temperatures struggle to get out of the 30's on Friday during the bulk of this precipitation. If snow manages to accumulate during the morning on Friday, we may see highs even below freezing for the day as well. Overall this will be a dynamic system that could change notably in the coming runs, but should be one of the more impactful systems we've seen since the start of the year.

LONG TERM /SATURDAY THROUGH MONDAY/

Issued at 205 PM MST Tue Mar 3 2026

The weekend will begin with a mid-level ridge building in across the High Plains which will be located in the left-entrance region of a 125 knot 250 mb jet, resulting in large-scale subsidence and dry conditions. Winds will begin to ramp up at this time as 50 knot zonal 700 mb flow will be in place. In-house random forest guidance has 80% probabilities of high wind conditions (> 58 mph) in the wind- prone areas of Bordeaux and Arlington. This is also reflected on the omega fields which show a classic mountain wave pattern. Model cross- sections also indicate a mountain-top stable layer given by a tight potential temperature gradient within the 700-600 mb layer which is a favorable signature for strong downsloping winds.

We will remain downstream of a cut-off low that is located over Southern California and the Baja Peninsula, placing us in a zonal flow regime. This will translate to dry and windy conditions with above-average temperatures into early next week. This cut-off low will eventually be ingested into the overall flow regime and will propagate towards the east as an open wave. While this shortwave trough is expected to remain well to our south, it may provide sufficient lift to promote some light precipitation. Generally, forcing for ascent appears to be weak at this time and given our progged location in the right exit region of a 150 knot jet (prime for subsidence), chances for beneficial moisture are low at this time.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 445 PM MST Tue Mar 3 2026

Potent Pacific storm system will drift southeast of the area this evening, with clearing skies and precipitation ending over the next few hours. Some dense fog is possible late tonight over the more sheltered valleys.

HAZARDS/WEATHER TRENDS: Conditions have improved significantly over the last few hours, so have VFR conditions going for most terminals through tonight and into early Wednesday with clearing skies. Concerns for fog are increasing, especially for KLAR and KRWL tonight with plentiful surface moisture and clearing skies expected. Added VCFG and light mist starting at 03z. If high resolution model trends continue, might have to be more aggressive with dense fog at these two locations.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Winter Weather Advisory until 5 PM MST this afternoon for WYZ103-110-112-114-116. NE...None.