textproduct: Salt Lake City

KEY MESSAGES, Issued 1255 PM MDT Sun Jul 19 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 continues 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 through at least Thursday. A Slight Risk (2/4) of exceeding flash flood guidance exists across southern and central UT this afternoon, Tuesday afternoon across southwest UT, and Wednesday across northern UT and southwest WY.

- A Flash Flood Watch remains in effect for southern UT and portions of Central UT this afternoon, ending around midnight.

- Hazardous temperatures look to develop across northern UT tomorrow afternoon, particularly along the I-15 corridor and West Desert. As such, a heat advisory has been issued.

DISCUSSION, Issued 1255 PM MDT Sun Jul 19 2026

Monsoonal moisture return continues across the southwest as ridging remains overhead. Beneath this ridge, PWATs in excess of 1" continue to push north across most valley locations with locations across southern UT potentially exceeding 1.6" PWATs once again this afternoon. Daily chances for showers, thunderstorms, and potentially flash flooding continue through at least Thursday across southern and central UT with this pattern in place. Modest moisture return continues to push across northern UT, though most storms have remained anchored to the terrain further east each afternoon due to drier PBL conditions across northwest UT valleys and considerably weaker steering flow. This brings great uncertainty to the forecast through Tuesday morning, keeping PoPs somewhat lower across most of the Wasatch Front and northwest UT compared to higher elevation locations. Deeper moisture looks to advect further north as some stronger synoptic forcing moves in from the west, increasing PoPs starting Tuesday afternoon with the highest confidence of heavy rainfall and Thunderstorms occurring Wednesday afternoon.

Thunderstorm development across central and southern UT will be somewhat delayed closer to 3pm today due to an early shortwave traversing the region, leaving some localized subsidence in its wake. PWAT anomalies across southern and central UT once again range from 0.5-1" of water as monsoonal moisture lingers this afternoon. CAPE profiles potentially in excess of 1000J/kg with deep warm cloud layers up to 3km continue to support the development of efficient rainmakers with heavy rain expected from well established storms. The stronger instability axis with CAPE values >= 1000J/kg once again 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.

As the ridge builds overhead, temperatures on Monday are forecast to reach into the upper 90s to low 100s across most valley locations across northwest UT. This has resulted in widespread "major" HeatRisk values, primarily within valley locations along the I-15 corridor and Great Salt Lake Desert, with a few areas reaching "major". Overnight relief following warmer temperatures today are forecast to increase the threat with overnight lows tonight generally ranging from the upper 60s to mid 70s. As such, a heat advisory has been issued for the aforementioned locations.

Forecast guidance continues to bring daily chances of rain across much of UT through at least Friday, though guidance is now in better agreement with drier mid-level air pushing into the Great Basin as we head into the weekend. This dry punch is associated with a mid- level trough that is forecast to impact the pacific northwest later this week bringing prolonged dry westerly flow through the end of the forecast period. This will serve to greatly limit precipitation chances across the forecast area as we enter the weekend, keeping any chances more than likely confined to higher terrain.

Lastly, some severe potential exists on Wednesday across northern UT and southwest WY as a shortwave trough traverses the Great Basin in the afternoon hours. Confidence regarding timing and location of this shortwave remain highly uncertain at this time, though the broad synoptic pattern associated with this would support a potential damaging wind threat if it were to materialize.

AVIATION

KSLC...There is a 10% chance of convection before 02Z Monday. NW winds will otherwise shift SE around 04Z, with lingering high level VFR cloud cover. Winds are then favored to shift back NW between 17- 19Z Monday. There is then approximately a 15-25% chance of showers or thunderstorms impacting the terminal, generally mid to late afternoon Monday. Any such activity will bring potential for lightning, brief reduction to CIGS/VIS, and gusty erratic outflow winds.

REST OF UTAH AND SOUTHWEST WYOMING...Like previous days anticipate convection across the region to wane through 03Z or so, with remnant outflows bringing potential for gusty and erratic wind gusts. Otherwise, anticipate some lingering VFR cloud cover, thickest near where convective coverage was highest (southern and central Utah), with winds favored to settle out to a diurnally normal to light and variable direction overnight. Monday will then will also see a similar progression to previous days with afternoon showers/thunderstorms developing, most widespread across southern to central Utah. This will bring potential for lightning, periods of heavy rain (and briefly reduced CIGS/VIS to MVFR or so), and gusty erratic outflow winds.

FIRE WEATHER, Issued 1255 PM MDT Sun Jul 19 2026

Monsoonal moisture remains across UT increasing humidities while raising chances for showers and thunderstorms across the state moderating fire weather conditions overall. Chances for showers and thunderstorms remain elevated across central and southern UT, and the Uintas ranging from 50-80%. A wetting rain remains favored this afternoon across each mentioned location. Expect showers and thunderstorms to develop along higher terrain parallel to I-15 each afternoon over the next several days around 1200-1400 with gusty outflow winds, heavy rainfall, and lightning. Winds will generally remain light terrain driven / diurnal over the next several days.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Heat Advisory from noon Monday to midnight MDT Monday night for UTZ101>105.

Flood Watch until midnight MDT tonight for UTZ122>128.

WY...None.