textproduct: Salt Lake City

DISCUSSION

A weak shortwave disturbance continues to ripple through Utah tonight. Moisture that spread into the area earlier today ahead of this disturbance aided in the development of widespread showers and thunderstorms across the area today. Isolated to scattered showers and isolated thunderstorms will continue through late tonight before waning early morning.

Lingering moisture on Thursday will once again allow for scattered convection to develop again during the afternoon and evening hours. Despite increased moisture in the lower levels, hi-res models are still indicating a threat of strong and gusty outflow winds with some of the storms. Additionally, cannot rule out the threat of localized heavy rain across southeast and east- central Utah where PWATs will be higher, which could bring a threat of flash flooding should the stronger cells move into the wrong area.

A drier airmass will then spread into the area for Friday, this as a trough strengthens into the PacNW. Southwest winds will increase over Utah ahead of this trough, with gusts in excess of 40 mph especially in portions of western and southern Utah. These winds, combined with drier conditions, will result in higher-end critical fire weather conditions. Red Flag Warnings are in effect. Later shifts may need to consider the need for Wind Advisories as well. After above normal temperatures for much of this week, a cold front crossing northern Utah Friday late afternoon to Friday night will bring temperatures down on Saturday, mainly for northern and west-central Utah.

As trailing energy continues to carve into the trough, southerly flow will again strengthen again on Saturday, especially across southern and central Utah. This will continue to bring critical fire weather conditions to the area. Some higher elevation sites may see fire weather conditions become moderated a bit due to slightly higher humidities, however. A stronger cold front is expected to push into the area Saturday night into Sunday. The critical fire weather conditions will decrease behind the cold front, but southeast Utah will remain ahead of the front through much of the afternoon and as such, may maintain critical fire weather conditions.

The associated airmass will be quite cold for this time of year, with afternoon max temperatures on Sunday expected to run 20 degrees below normal across the north to 10 degrees below normal across the south, and some northern valleys may fail to even reach 70 degrees. Some precipitation is expected to develop across northern Utah behind the front, but as skies clear out Sunday night, patchy frost may be possible, particularly in the Cache Valley and Wasatch Back.

A general southwest flow will follow through at least the first half of next week. This will allow temperatures to gradually trend warmer again. However, some localized critical fire weather conditions may remain a possibility, especially across the eastern valleys.

AVIATION

Winds will remain out of the southeast overnight, gradually decreasing in magnitude over the next few hours and beginning to increase again after 15z. While the typical diurnal wind shift is expected around ~19-20z, scattered showers and thunderstorms developing after 20z will likely cause gusty and erratic outflow winds at times through the afternoon. Wildfire smoke will continue to produce slantwise VIS reductions at times.

REST OF UTAH AND SOUTHWEST WYOMING...Showers and a few rumbles of thunder will continue to dwindle through the overnight hours, likely ending by 12z statewide. While winds will be largely light and terrain-driven overnight, showers may produce brief periods of more erratic winds. Scattered showers and thunderstorms will develop once again after 19z across Utah and southwest Wyoming, and will be capable of producing gusty and erratic outflow winds in excess of 40- 50kts. Wildfire smoke will continue to produce slantwise VIS reductions, particularly across central/eastern Utah.

FIRE WEATHER, Issued 509 PM MDT Wed Jun 24 2026

A moisture gradient will develop over Utah today brining scattered showers and thunderstorms. Across southern into south- central Utah storms will be tend to lean a on the wetter side, while farther north into central and northern Utah drier air will remain in place supporting high based thunderstorms that will lean on the dry side with the potential for strong gusty outflow winds. Outflow wind gusts of 30-40 mph will be common across west- central Utah into the Wasatch Front today, with localized wind gusts up to around 60 mph from the stronger storms. For this threat, a Red Flag Warning has been issued today for scattered dry thunderstorms and strong outflow winds.

This moisture will linger across Utah on Thursday but will start to dry out from west to east, which will shift the best coverage of thunderstorms across northern into eastern Utah with drier air intruding across west-central and southwest Utah. This will bring a localized flash flood threat across southeast Utah on Thursday, but also will still bring the potential for isolated dry thunderstorms and gusty winds across northern into north-eastern Utah.

There is then high confidence in a signficiant critical fire weather pattern for Friday into Saturday across the state with very strong southwest wind gusts of 40 to 50 mph combined with low RH values in the 5-10 percent range, and extremely poor recoveries Friday night. This pattern will develop from a strong system moving in from the Pacific northwest, thus there is high confidence in a strong wind field developing across Utah ahead of this approaching cold front, while very dry air gets drawn up across Utah ahead of the front as well, quickly sweeping out the mid-week moisture. Some locations across southeast Utah may see critical fire weather conditions from wind and RH last for more than 24 hours from Friday with no break Friday night and right into Saturday.

We are growing increasingly concerned with this setup could be the most signficiant fire weather setup we've seen this year, coming on the heels of an active week with large fires burning already, the potential for dry thunderstorms today and Thursday which could result in new fire starts and then concluding the week with a higher end wind and poor overnight recover event. The only silver lining is that the cold front will bring temperatures 25 degrees cooler across northern Utah by Sunday with an increasing humidity. However southern Utah will only cool by about 10-15 degrees with min RH values only coming up to around 15%.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Red Flag Warning from noon Friday to midnight MDT Saturday night for UTZ478-482-484-488-489-492-495-497.

Red Flag Warning from noon Friday to 3 AM MDT Sunday for UTZ493- 494-496-498.

WY...None.