textproduct: Salt Lake City

KEY MESSAGES, Issued 1239 PM MDT Sat Aug 15 2026

- Isolated thunderstorms are expected across southwestern and northeastern Utah this afternoon and evening. Locally heavy rain will be possible with any thunderstorms across southwestern Utah, though the flash flood threat is lower than prior days.

- Elevated to locally critical fire weather conditions will occur across central and southern Utah Tuesday into Wednesday.

DISCUSSION, Issued 1239 PM MDT Sat Aug 15 2026

Drier air continues to filter into the region under fairly weak southwesterly flow, resulting in quieter conditions this weekend across Utah and southwest Wyoming. Still, rainfall over the past few days has resulted in a relatively moist boundary layer, with dewpoints this morning still in the 50s across many areas. With this low-level moisture, isolated showers and thunderstorms will redevelop this afternoon, primarily over higher terrain and over far southwestern Utah. The flash flood threat is much lower today as the air mass trends drier, but a Flash Flood Potential Rating of Possible is still in place today for Zion and Snow Canyon given slow storm motions and this lingering low-level moisture.

While a ridge across the Southern Plains will still be the main large-scale feature in our forecast, a shortwave trough moving through the Interior Northwest on Tuesday into Wednesday could act to enhance southwesterly flow and draw moisture/thunderstorm chances across northern Utah, particularly on Tuesday afternoon. Forecast uncertainty increases thereafter, though model guidance does favor high pressure strengthening once again over the Four Corners region, which could bring back monsoonal moisture as early as Wednesday (but likely Thursday or later). With strengthening high pressure, temperatures will also slowly increase back to around normal by mid-week.

AVIATION, Issued 1239 PM MDT Sat Aug 15 2026

KSLC...Southerly winds are expected to shift to the northwest between 19-20z, with a return to southeasterly around 03-04z. VFR conditions under quiet skies are in store for the terminal today.

REST OF UTAH AND SOUTHWEST WYOMING...Terrain driven winds can be expected across the airspace today. Isolated showers or even a thunderstorm will be possible across northeastern and southwestern Utah, with a 30% chance or less of impacting nearby terminals.

FIRE WEATHER

A drier air mass will continue to shift into the region, with humidities expected to decrease through at least mid-week statewide. Valley RH will reach critical levels as early as Sunday, becoming more widespread heading into the work week. Overnight RH recoveries will become increasingly poor through at least Wednesday morning, with many valleys only reaching 30-45%. A system moving through the Interior Northwest will bring an increasing threat of gusty winds...with elevated to locally critical fire weather conditions Tuesday and Wednesday across primarily central and southern Utah. Isolated thunderstorms are possible today and Sunday afternoon mainly across higher terrain, with otherwise little to no wetting rain chances.

SLC WATCHES/WARNINGS/ADVISORIES

UT...None. WY...None.