textproduct: Salt Lake City

KEY MESSAGES, Issued 1231 PM MDT Thu Aug 13 2026

- Monsoonal moisture looks to bring daily chances for showers and thunderstorms across much of UT through Friday before drying out this weekend.

- A flash flood threat exists across southwest UT and the central UT mountains this afternoon. Confidence is highest regarding impacts across southwest UT.

- A severe weather threat exists across northern UT today with damaging winds (>58mph) as the primary threat.

DISCUSSION

The forecast area remains sandwiched between an area of high pressure to the east and a broad area of low pressure off to the west, with shortwave energy continuing to lift through the region this evening. The pairing of the shortwave energy and the monsoonal moisture on the western periphery of the ridge continues to support shower and thunderstorm activity across the region, with a rather widespread area of stratiform rain across a portion of northern Utah. Isolated thunderstorms continue to build in west-central and southwest Utah this evening, with isolated to widely scattered storms expected to continue into the early morning hours across this same region. As such, the threat for heavy rainfall and flash flooding will remain somewhat elevated through early Friday morning, with primary concern areas being the Cottonwood burn scar and Widemouth 2 scar.

Moisture remains in place through the day tomorrow with another subtle shortwave trough lifting through the region which will help to bring another round of showers and thunderstorms across the forecast area. As has been the case for the past several days, the increase in atmospheric moisture and instability in place across the region will bring the potential for heavy rainfall and flash flooding with developing thunderstorms if they end up in the wrong place (i.e. burn scars, slot canyons, dry washes, and poor drainage / urbanized areas).

Increasing subsidence in the wake of this shortwave will spread over the region over the weekend, helping to decrease the overall coverage of showers and thunderstorms areawide. That said, moisture will still remain in place and allow for at least isolated showers and thunderstorms to develop over the high terrain features, particularly in southern Utah and in the Uinta Mountains. Coverage of precipitation will decrease further into Monday and Tuesday as mid-level moisture wanes, however, we'll increase chances once again on Wednesday as the northern stream becomes more active.

AVIATION...KSLC

Showery conditions persist through around 06z, becoming dry thereafter. Winds remain generally light out of the southeast overnight, transitioning to the northwest after around 20z. Afternoon convection will be more isolated across northern Utah on Friday, with a 15% chance for a thunderstorm to impact the terminal with gusty and variable winds between 20-24z. Conditions remain VFR through the TAF period with a persistent mid and high level cloud deck.

REST OF UTAH AND SOUTHWEST WYOMING...Convective activity will wane across the entire airspace after 08-09z. VFR conditions prevail for all regional terminals through the TAF period, with a persistent mid to high level cloud deck across the region. Convective activity is expected to develop once again, with widely scattered coverage across central and southern Utah starting around 19z. Storms will be capable of producing gusty and erratic outflow winds and brief heavy rainfall.

FIRE WEATHER

A monsoonal surge will bring showers and thunderstorms with the potential for severe wind gusts (>58mph) to much of UT today as well as the potential for flash flooding across southwestern and central UT. Both severe and flash flooding threats taper off somewhat tomorrow, though afternoon thunderstorms capable of heavy rain and gusty and erratic outflow winds are expected. Humidities will begin to decrease heading into next week with lower elevation locations potentially dropping below 20% starting Monday as we continue to dry out. A return to monsoonal moisture is possible following midweek, though this remains uncertain at this time and the drying trend remains somewhat favored through the long term.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Flood Watch through Friday morning for UTZ116-117-122>129.

WY...None.