textproduct: Salt Lake City

KEY MESSAGES, Issued 1210 PM MDT Fri Jul 17 2026

- Scattered showers and thunderstorms are expected to develop across portions of central, southern, northeast UT, and southwest WY each afternoon within this forecast as monsoonal moisture continues making its way north.

- The risk for flash flooding exists across the majority of the forecast area, highlighted by WPC with a Marginal Risk (1/4) of exceeding flash flood guidance each day encompassing nearly all of UT. A Slight Risk (2/4) of exceeding flash flood guidance exists across southwest UT this afternoon and Saturday.

- A Flash Flood Watch remains in effect for southern UT and portions of Central UT this afternoon, ending around midnight. Another Flash Flood Watch has been issued for tomorrow afternoon, encompassing the same areas.

DISCUSSION, Issued 1210 PM MDT Fri Jul 17 2026

A favorable monsoon pattern persists across the southwest as large-scale ridging remains overhead. Beneath this ridge, moisture continues to advect north across UT raising PWATs areawide in excess of 1" of water across nearly all valley locations with lower Washington county potentially seeing PWATs in excess of 1.6" this afternoon. This pattern is forecast to persist over the next week or so, keeping chances for rain and thunderstorms each afternoon in the forecast for most locations across the state with a particular emphasis on southern UT. Chances for rain and thunderstorms begin to increase across northern UT today, increasing more near the end of the week as deeper moisture continues to advect north.

With PWAT anomalies statewide ranging from 0.5" to nearly 1" this afternoon, the threat for flash flooding is expected to continue. The threat remains elevated due to weak steering flow aloft yielding storm motions generally around 10kts or less. While this has increased somewhat over the past couple days, deeper moisture coupled with a taller, skinnier CAPE profile (potentially in excess of 1000J/kg) with a deeper warm cloud layer supports another round of efficient rainmakers with heavy rain expected from mature storms. The stronger instability axis with CAPE values >= 1000J/kg currently resides across southwestern UT, supported by both SPC Mesoanalysis and current CAM guidance, with storms expected to initiate along higher terrain and propagate down terrain toward the instability gradients. The main concern with a more elevated flooding threat further southeast would be cold pool development as storms propagate west potentially raising CIN across southeastern UT. If initiation were to occur earlier, however, a locally higher flooding threat may develop across southeastern UT this afternoon. A nearly identical threat exists Saturday as well given similar synoptics and moisture quality across the region.

From Sunday on, some uncertainty develops regarding storm motions which would potentially inhibit the flash flood threat. While quality moisture remains in place, storm motions may potentially see a slight uptick beginning Sunday as the aforementioned ridge slowly shifts east. Slightly stronger southwest flow continues to push in each afternoon from Monday on, potentially inhibiting this further as storms may tend to move off terrain quicker instead of training over one location. These details may be difficult to iron out fully until the day before, though isolated flash flooding is expected at a minimum each day going forward from Sunday on.

AVIATION, Issued 1214 PM MDT Fri Jul 17 2026

KSLC, Issued 1214 PM MDT Fri Jul 17 2026... Light southerly winds will gradually transition to northwesterly between 18-19Z. Showers are expected to develop along the high terrain around 21Z forward. There is around a 30-40% chance that showers/ thunderstorms move off the terrain and over the airfield after 23Z, with potential continuing through around 04Z. These storms will be capable of producing gusty and erratic outflow winds with gusts to 30 kts. VFR conditions are expected to prevail through the period, however, any showers moving over the area may drop VIS to the MVFR category and CIGS to below 6000 feet.

REST OF UTAH AND SOUTHWEST WYOMING...Widespread showers and thunderstorms are expected across the airspace this afternoon and evening. Greatest coverage will favor southwest and south-central Utah, with potential to produce heavy rainfall that may drop VIS into MVFR. Across the northern portion of the airspace, storms will be capable of producing gusty and erratic outflow winds to 30 kts through this evening. Otherwise, storms taper off late this evening across the airspace with generally light winds prevailing areawide.

FIRE WEATHER

Currently, monsoonal moisture continues to surge north into UT increasing humidities and raising chances for showers and thunderstorms across the state, both serving to moderate fire weather conditions. Chances for showers and thunderstorms remain highest across southwest UT, high terrain from southern to northern UT, and the Uintas generally ranging from 60-90%. Additionally, these locations are where a wetting rain is favored this afternoon. Moisture continues to surge into northern UT into this weekend, keeping chances for showers and thunderstorms elevated into next week each afternoon.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Flood Watch until midnight MDT tonight for UTZ122>128.

Flood Watch from Saturday afternoon through Saturday evening for UTZ122>128.

WY...None.