textproduct: Salt Lake City

KEY MESSAGES

- Scattered showers and thunderstorms will redevelop over the area on Tuesday. Localized flash flooding will be possible, with the greatest threat across southern and eastern Utah and near recent burn scars. - Some modest drying will occur for the middle of the week. With breezy southwest winds expected during the mid to late week timeframe, elevated fire weather conditions will become a possibility.

- There is an increasing probability that deep moisture associated with a tropical cyclone in the Eastern Pacific will spread northward into Utah ahead of a Pacific disturbance for Labor Day weekend.

DISCUSSION

A shortwave trough continues to eject across northern Utah this evening, bringing continued showers and thunderstorms to the area. Isolated to scattered nocturnal convection is expected to linger overnight. Runoff from earlier heavy rain will continue to cause rivers and streams to run high through much of the night, but the threat of additional flooding has decreased significantly.

On Tuesday afternoon, another, weaker, shortwave trough will eject across Utah. This will bring another round of showers and thunderstorms to the area. With weaker dynamics and decreasing PWATs, convection will not be as widespread compared to today. And while the threat of flash flooding will exist, it will also be less compared to today. There is currently a Marginal Risk of excessive rainfall for southern, eastern, and portions of central Utah for Tuesday.

Wednesday through Friday should feature a bit of a lull in the weather as the airmass continues to trend drier. However, with enhanced southwest winds owing to a mean trough over the PacNW, depending on how quickly the airmass and fuels dry out, focus may shift to fire weather concerns for midweek to late week timeframe as fire weather conditions become increasingly elevated.

For the holiday weekend, models indicate some moisture being drawn into the area from a tropical system over the eastern Pacific. However, there remains some uncertainty as to how much of this moisture will reach the forecast area.

AVIATION

KSLC...VFR conditions continue at the SLC terminal through the valid TAF period. A potential for rain showers will continue through around 08z tonight, with the next potential (20-30% chance) for showers Tuesday afternoon. Southerly winds are expected to prevail through Tuesday, but may be variable at times Tuesday afternoon near showers.

REST OF UTAH AND SOUTHWEST WYOMING...A few showers linger across the region to start the TAF period but will dissipate. VFR conditions are expected to prevail through the overnight with decreasing clouds and weakening winds. Showers and thunderstorms are forecast to once again be possible Tuesday afternoon and evening. Coverage will be less with southern terminals such as KCDC and KSGU having low chances for a shower or storm. Winds increase by the late morning hours with speeds of 15 to 20 knots and gusts of 25 to 30 knots at times. Gusty outflow winds will be possible with any developing showers or thunderstorms during the afternoon and evening. Outflow winds of 30 to 40 knots cannot be ruled out at any terminals nearby developing convection. MVFR to even IFR conditions may be possible with any showers or thunderstorms that move directly overhead a terminal. Precipitation should gradually dissipate after sunset with most terminals seeing dry conditions to end the TAF period.

FIRE WEATHER, Issued 1254 PM MDT Mon Aug 31 2026

Showers and thunderstorms are continuing to develop and will only increase in coverage across the entire state into the evening as a low pressure system crosses the area in an already moist airmass. This will bring a high chance (50 to 85 percent) of wetting rain, particularly for the higher terrain of central and southern Utah. Relative humidities will also remain on the high side, with very few locations falling below 30 percent. Drier air will start to move in from the west on Tuesday, but this should not be noticeable for much of the area until Wednesday into Thursday. This is likely to push minimum relative humidity values into the teens across western Utah Wednesday into Thursday. In combination with breezy southerly winds due to a low along the Pacific coast, this could bring area of critical fire weather conditions. The period of dry weather should be short lived, however, with guidance increasingly indicating a substantial surge of tropical moisture into Utah over the weekend.

SLC WATCHES/WARNINGS/ADVISORIES

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