textproduct: Salt Lake City

KEY MESSAGES

- Scattered high-based convection is expected to develop both Tuesday and Wednesday afternoon across northern and central UT into southwest WY. Both days will feature gusty outflow winds capable of gusts to 50mph with scattered severe gusts in excess of 58mph.

- Elevated to locally critical fire weather conditions are expected across southern UT Tuesday afternoon, expanding into central UT on Wednesday as gusts increase with a decrease in RH.

- Probabilities for a notable heat wave developing late this week continue to increase resulting in areas of major HeatRisk developing statewide. Valley temperatures are forecast to reach and/or exceed 100F Saturday, Sunday, and potentially Monday.

DISCUSSION

Large-scale ridging continues to build over the Four Corners resulting in broad southwesterly flow aloft over much of the region as troughing persists off the west coast of BC. With persistent southwesterly flow aloft, ample mid-level moisture will continue to overspread the Great Basin Tuesday and Wednesday as the aforementioned trough slowly meanders east with time. Multiple embedded shortwave perturbations are expected to move across the Great Basin in the afternoon hours on Tuesday and Wednesday, and with ample mid-level moisture in place, high-based showers and thunderstorms are expected to develop across northern and central UT as well as southwest WY. Given modest DCAPE values ranging from 1500- 1800J/kg each afternoon, strong wind gusts to around 50mph are expected, and a few severe gusts in excess of 58mph cannot be ruled out.

Of the two days, Wednesday appears to have a somewhat higher ceiling than Tuesday, primarily regarding overall coverage and gust magnitude. This is mostly due to a more robust shortwave traversing the region providing more large-scale ascent favoring widely scattered storm development. Additionally, mid-level flow ranging from 40-50kts is forecast to push across northern UT in the afternoon hours, serving to increase eff. shear to roughly 20-30kts, increasing the potential for more organized and long-lived convection. This may result in a few instances of severe gusts to around 70mph, though mid-upper flow leaves some to be desired compared to previous setups. Lastly, ML guidance has been hinting at higher probabilities and confidence for severe wind gusts across northern UT Wednesday afternoon, increasing forecaster confidence somewhat regarding the development of severe weather.

On Wednesday and Thursday, mid-level flow is forecast to become more zonal in nature following the departure of the aforementioned trough ejecting northeast further into CA. Drier air is expected to work its way into the region as westerly flow aloft develops, hindering afternoon convective development somewhat outside of higher terrain each afternoon. Additionally, temperatures aren't forecast to increase significantly compared to the past few days as geopotential heights remain somewhat stagnant over the Great Basin.

On Friday, ridging is forecast to build significantly over the Intermountain West, kicking off a period of prolonged heat, very dry air, and poor overnight recoveries. On Friday, most valley locations will begin to flirt with 100F with much of the West Desert seeing temperatures break into the 100s. On Saturday, the majority of our valley locations are forecast to break into the 100s with lower Washington county flirting with 110F. This threat is forecast to continue into Sunday and perhaps Monday, with very little change in temperatures resulting in widespread Major HeatRisk along the I-15 corridor with some pockets of Extreme appearing across the Wasatch Front on Sunday.

Some relief appears to develop Tuesday and beyond the extended forecast period as the strong ridge begins to slide east somewhat. If this were to occur, this would set the stage for favorable monsoonal moisture return across southern UT, perhaps into northern UT by mid-July. Ensemble guidance continues to favor the development of our first meaningful monsoonal pattern of the year, potentially bringing much needed moisture to the forecast area.

AVIATION

KSLC...Winds expected to gradually settle southerly overnight with SCT to BKN VFR clouds lingering above ~12 kft. Winds then anticipated to shift NW around 18-20Z. There will once again be potential for afternoon convection and associated erratic gusty outflows, though at this time it is around a 10-20% chance of impacts at the terminal. Otherwise, VFR skies with mid/upper level clouds continue to prevail.

REST OF UTAH AND SOUTHWEST WYOMING...Forecast pattern for Tuesday looks similar to that of Monday as the associated system lingers. This will result in afternoon convective potential at northern terminals, though with less coverage expected than Monday, and favoring areas further north and east. Still, this will result in potential for some gusty erratic outflow which would interrupt the typical diurnal wind cycle if near any terminals. Skies largely expected to remain VFR with SCT to BKN cloud cover generally above 10 kft. At southern terminals, clear conditions are maintained, with fairly typical wind directions and speeds.

FIRE WEATHER, Issued 122 PM MDT Mon Jul 6 2026

High based moisture which spread across the region over the last 24 hours will continue to bring a chance for high based showers and dry thunderstorms through this evening, and again Tuesday afternoon and evening, mainly north of I-70/US-50. In addition to lightning, strong outflow winds to 50 mph will be possible with these storms. With this moisture in place, RH has trended higher today, which will result in improved overnight recovery and elevated RH again Tuesday across northern and central Utah. Further south, drier air will allow afternoon RH values to fall near or below 15% across southwest Utah, which will result in elevated to near critical fire weather conditions in zone 495 and 497.

A drier westerly flow Wednesday into Thursday will drop daytime RH values below 15% across most elevations below 8000 feet across central and southern Utah. This combined with the westerly flow will result in elevated to locally critical fire weather conditions. At this time these locally critical conditions don't look to be widespread enough to warrant a Fire Weather Watch. A strong area of high pressure will bring hot temperatures and very low RH to the region late this week through the upcoming weekend. This high is expected to move far enough east next week to allow monsoon moisture to spread into the region around the July 14th-15th timeframe.

SLC WATCHES/WARNINGS/ADVISORIES

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