textproduct: Cheyenne

KEY MESSAGES

- Slight Risk of severe thunderstorms this afternoon through Thursday with heavy rainfall, hail, and strong gusty winds possible.

- A ridge builds late in the long term, drying the area out and heating things up.

SHORT TERM /THROUGH WEDNESDAY NIGHT/

Issued at 149 PM MDT Tue Jul 7 2026

Current regional observations are already a little toasty along and east of I-25 with temperatures in the low to mid 90s, except under the mid and high level cloud cover. A few spots near Chadron and Scottsbluff could reach 100 before storms move in this afternoon. The south to southeast winds are advecting in 40 to 50 degree dewpoints over the Nebraksa Panhandle areas. Aloft we have decent near saturated mid layers and a shortwave which will help kick off some elevated and high based convection. Wind shear is lacking in todays environment, much like it was yesterday. The bulk wind shear values are in the 20-30 knot ranges which will favor pulse type storms with short lifespans. Some gusty winds can be anticipated with DCAPE values in the 1000-1500 J/kg range combined with dry adiabatic sub cloud layer lapse rates. The Storm Prediction Center has introduced a marginal to slight probabilities over much of the area for severe hail and winds. The environment does favor marginally severe hail and winds to 60 mph with the most impressive thunderstorms. Towards the northern CWA counties and in the upper Nebraska Panhandle areas there may be better instability and DCAPE values on the higher end to support winds to +70 mph. At the time of writing this discussion we have convective initiation near Cheyenne which should become more widespread with a favored propagation along the east and northern flanks. More widespread development is anticipated in the next few hours area wide moving to the northeast. Towards the evening marginally severe hail looks possible for mainly the Panhandle area. By midnight most areas should be free of storms, except for a possible complex moving through Carbon County late in the night. Briefly mention that some fire zones in Carbon and Albany County will have elevated fire conditions this afternoon. Patchy areas of red flag conditions are possible when RH values dip into the teens and winds increase. Additionally, dry thunderstorms are possible. Condition coverage is not great enough to issue a red flag product.

Wednesday is similar to today, but shear and upper level flow appears better given another shortwave moves in from the west. This shortwave is well timed with the peak afternoon heating and should promote widespread thunderstorms. Surface winds are rather weak and will keep low level shear on the low side. Hodographs are straight and most of the instability above the freezing level will favor large hail development. Surface spreads will be less than the last few days which will help more precipitation reach the surface. Shear to the south of the shortwave feature are anticipated to be in the 40-50 knot ranges which is adequate for supercells in the northern Panhandle areas. With mostly speed shear these storms will be predisposed to grow upscale into line segments.

LONG TERM /THURSDAY THROUGH MONDAY/

Issued at 149 PM MDT Tue Jul 7 2026

Thursday...As has been typical in the past week, a neutrally tilted shortwave trough, or perturbation aloft, will develop along the Wyoming and Nebraska state line, with an associated low level convergence axis along the I-25 corridor, sparking scattered to numerous showers and thunderstorms in the afternoon and evening east of I-25, with lesser coverage further west. Temperatures will be moderated by cloud and convective precipitation coverage, with 700 mb temperatures yielding maximum temperatures in the 80s.

Friday...The atmosphere dries out considerably with shortwave ridging aloft bulging over eastern Wyoming, and with 700 mb temperatures from 12 to 15 Celsius, producing decent convective inhibition, CIN, thunderstorms are quite unlikely. A warming trend develops with less cloud and convective coverage.

Saturday through Tuesday...Ridging aloft dominates our region, with quite dry air at low and mid levels, accompanied by 700 mb temperatures from 15 to 20 Celsius, thus chances for late day showers and thunderstorms will be minimal at best, and dry weather will prevail. The 700 mb temperatures will yield maximum temperatures in the 90 to 105 degree range. A weak perturbation and a slight increase in mid level moisture may spark isolated thunderstorms on Tuesday.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1139 AM MDT Tue Jul 7 2026

A shortwave trough will move to the Wyoming and Nebraska state line this afternoon, while a low level convergence axis develops from Douglas to Cheyenne, sparking isolated to scattered thunderstorms this afternoon and this evening, with isolated to scattered thunderstorms continuing from Douglas to Chadron into the late evening hours.

Wyoming TAFS...VFR prevails. High confidence in isolated to scattered showers and thunderstorms from 21Z to 01Z at Rawlins, 18Z to 00Z at Laramie,and 20Z to 02Z at Cheyenne, with some storms producing gusty and erratic wind gusts to 45 knots along with localized MVFR visibilities. Clearing skies this evening. Gusty usual gradients winds until sunset, then again after mid morning Wednesday.

Nebraska TAFS...VFR continues. High confidence in isolated to scattered thunderstorms, with the most areal coverage at Chadron and Alliance, and lesser so at Scottsbluff and Sidney, with scattered thunderstorms at Chadron and Alliance from 21Z to 03Z, with some storms producing wind gusts of 45 to 50 knots along with brief MVFR visibilities. Expect MVFR ceilings and visibilities in low clouds and fog at Alliance and Chadron from 09Z to 13Z. Skies will become mostly clear Wednesday morning. Gusty gradient winds will occur until sunset, and again after 15Z Wednesday.

At Scottsbluff and Sidney, storms should be less coverage than further north, though occur from 20Z to 00Z at Scottsbluff, and 22Z to 03Z at Sidney, with the strongest storms producing wind gusts near 45 knots, along with brief MVFR visibilities. Skies will clear out late this evening and overnight. Gusty gradient winds will occur until sunset, and again after 15Z Wednesday.

CYS WATCHES/WARNINGS/ADVISORIES

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