textproduct: Western and Central Wyoming

KEY MESSAGES

- Today will be similar to yesterday with seasonably warm temperatures and isolated to widely scattered showers and thunderstorms, mainly in northern and western Wyoming. Any shower or thunderstorm could have strong wind gusts.

- The chance of storms decreases Friday, with The 4th of July looking largely rain free across the entire area.

- Temperatures become above average starting Friday, with the hottest day expected on Sunday.

DISCUSSION

Issued at 230 AM MDT Thu Jul 2 2026

Happy Independence Day everyone! This is actually the day we declared Independence from England since the Continental Congress voted and declared independence on July 2nd, not July 4th. Americans first saw the Declaration of Independence on July 4th, that is when we celebrate.

And mother nature will help us celebrate by providing some of the natural fireworks see is infamous for, AKA thunderstorms. The pattern continues to show the Death Ridge across the Eastern Unites States. We continue to have a mean trough over the western portions of the USA but it continues to flatten. At the same time, another shortwave will be moving over the top of the ridge and bringing another round of thunderstorms. Parameters are fairly similar to yesterday. There will be some CAPE but nothing off the charts (generally maxing out at around 500 J/KG across the west and in Johnson County, with less basically none in southeastern portions of the area), and lifted indices generally dropping down to minus 2. The limiting factor will again be moisture, with most areas having below the seasonal average (the average is around 0.55 inches in early July). There will be some factors in favor of storms though. For one, lapse rates are very steep, over 9C/km in some locations. There will also be a decent amount of directional shear around. As for the outlook, the marginal risk remains in a similar location, largely East of Interstate 25 in Johnson County. As for threats, by far the greatest threat would be strong wind gusts. All areas have at least a 35 degree dew point depression, with some locations East of the Divide having as much as 65 degrees. Model soundings also show high cloud bases, increasing the chance of dry microbursts. This is a day when any thunderstorm, shower or even cumulus cloud could collapse and produce strong wind gusts. This looks like it could be one of those infamous "Little Green Blob" days. As for hail, the main threat would be in northern Wyoming where there is a bit more moisture. Coverage looks sparse though, generally less than a 1 in 3 chance across the north to less than 1 in 10 in southeastern portions of the area, so most locations should not see one. Most convection should end around sunset, although a few showers may linger through the night. Temperatures should average close to yesterdays, perhaps a few degrees warmer, so warm but not really hot.

Flow will essentially become zonal by Friday, with even drier air pushing into much of the day. Models have trended a bit drier on this day as well, with most of any convection largely across northern Wyoming as another shortwaves tops the ridge. Once again, the main threat from any shower or thunderstorm would be strong winds. Chances on this day are 1 out of 4 or less for all locations. As for temperatures, once again similar to Wednesday with warm but not overly hot conditions. And as far as fire weather, humidity will be rather low. However, wind should remain light to moderate for the most part, so no fire weather highlights are anticipated at this time.

Now on to the celebrated Independence Day, July 4th. And at this time, conditions look fairly nice. It will be a hotter day across the area. Not hot as a firecracker, but it will definitely feel like mid summer. Almost all the lower elevations will have highs at least in the 80s with many locations East of the Divide cracking 90. The best news is that shortwave ridging should be over the area, bringing upper level divergence. This, combined with precipitable water values only 80 percent of normal, means less than a 1 in 10 chance of a shower or thunderstorm anywhere in the area. The main concern will be the very low humidity, falling close to the single digits in some locations. However, once again wind is expected to remain light to moderate.

The chance of thunderstorm looks to return Sunday and Monday, although convection looks to remain relatively isolated and largely across northern Wyoming. Tuesday may bring a better chance of storms as a weak cold front passes through and a bit of moisture return may increase coverage somewhat. As for temperatures, the heat looks to peak on Sunday when some of the warmer spots in the Bighorn Basin may get close to 100 degrees. Things turn a bit cooler for the middle of the week with more clouds and chances for storms but not cool by any means.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 958 PM MDT Wed Jul 1 2026

A few weak showers continue to linger across the area for the start of the TAF period. However, little to no impacts are expected at any terminals with VFR conditions likely to persist through the period. Light winds of 5 to 10 knots across all terminals overnight into Thursday morning. Winds gradually increase for most terminals by the early afternoon (18-20Z) with winds of 10 to 15 knots and gusts of 20 to 25 knots at times. Showers and thunderstorms are forecast to start developing around 20Z Thursday with all terminals except KCPR either having nearby convection (VCTS) or direct impacts from showers/storms. The main concern with any storms that develop will be strong gusty outflow winds of 30 to 40 knots. Showers and storms are likely to linger past 00Z Friday with things gradually dissipating by 04Z Friday. Some terminals may see breezy winds linger into the end of the TAF period with most seeing light winds return shortly after 06Z Friday. Mountain top obscuration may be possible at times Thursday, especially across central/western portions of the state where showers and thunderstorms will be more likely.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on smoke, icing and turbulence forecasts.

RIW WATCHES/WARNINGS/ADVISORIES

None.