textproduct: Cheyenne

KEY MESSAGES

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

- An upper level ridge is may bring Red Flag conditions and potential heat advisory headlines starting this weekend.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 223 AM MDT Thu Jul 9 2026

Today will be almost a wash, rinse, and repeat of yesterday. Models have showers moving into our area around 18z with thunderstorm development occurring around 21z. Convection looks to follow the diurnal trend once more with severe thunderstorms coinciding with prime heating and then waning off around 04z. Most of our forcing looks to exit our area around 03z so there may be some lingering showers going until about 06z or midnight. Bulk shear looks to be around 30-40kts with a temporary increase in intensity of 50kts near the WY/NE border around 00z then pushing east into central Nebraska. The thunderstorms will probably be pulsy until that better shear occurs to really organize and sustain the thunderstorms. Main threats will be gusty winds especially when the storms are pulsy. But once the storms start to organize the hail threat will increase with hail stones potentially up to golf balls but the window for that large of hail is going to be pretty limited as the forcing starts to depart the area. Torrential rainfall looks likely again as PWAT values creep towards the 1.0 to 1.25 inch mark. Urban flooding may be a factor to consider for today especially if the storms are slow moving since the upper levels winds look pretty lackluster for today.

Friday, the intermountain west starts drying out as the upper level ridge starts build over the region. Min RH values look to range from 15 to 25 in Southeastern Wyoming and 25 to 35 percent in the Panhandle for elevated fire weather concerns. In the afternoon there is small/isolated chance of showers mainly near the Colorado with some models having a few showers move in from Colorado and dissipate in our forecast area. Low pops were kept to convey this possible outcome.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Issued at 223 AM MDT Wed Jul 8 2026

Update: Sunday through Tuesday looks like widespread Red Flag conditions as synoptic winds increase with daily RH values dropping below 15 percent. This combustible environment may undue all the work the beneficial rain did the past couple days. Combined with the warmer temperatures any fine fuels will probably cure to carry a wildfire if one develops.

Previous Discussion.

Saturday through Wednesday...Ridging aloft dominates our region, with quite dry air at low and mid levels, accompanied by 700 mb temperatures from 14 to 21 Celsius, thus chances for late day showers and thunderstorms will be nearly nil and non existent, 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, and moreso on Wednesday, along the convective inhibition aloft gradient along the I-25 corridor and further to the west.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1108 PM MDT Wed Jul 8 2026

Showers continue to move off to the east, currently only impacting the KAIA terminals with light rain. Mostly cloudy skies continue across western Nebraska for the next 1 to 2 hours before clearing out into mostly clear skies overnight. With all the precipitation this evening, isolated, patchy fog may develop at KLAR, KCYS, KBFF, KSNY, and KAIA overnight into the early morning hours. Included TEMPO groups to cover this threat, though confidence is low at this time. Another round of showers and thunderstorms returns in the afternoon, with gusty and erratic winds expected in and around any showers or storms that develop.

CYS WATCHES/WARNINGS/ADVISORIES

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