textproduct: Salt Lake City

KEY MESSAGES

- An influx of smoke originating from numerous fires across the Pacific Northwest will continue through at least Thursday.

- A gradual warming trend through the latter half of the week brings the potential for widespread dangerous heat to develop Friday into Saturday.

- Chances for afternoon showers and thunderstorms with microburst potential begin as early as Thursday across southwest Utah, with the threat becoming more widespread early next week as monsoon moisture surges northward.

DISCUSSION

Utah and southwest Wyoming are under a dry west to northwest flow this evening as high pressure rebuilds along the Pacific coast. High temperatures stayed up to 5F below seasonal normals over northern portions of the area, while temperatures stayed abnormally hot over southern Utah. A high of 99F at Cedar City tied the record high for the date, with some possibility that other daily records were broken.

The ridge will continue to build over the next few days, slowly shifting east as it does so. By Friday, the ridge is expected to be overhead, and highs up to 10F above seasonal normals will be common for both Friday and Saturday, bringing the potential of an increase in heat related illness.

The position of the ridge is expected to allow a subtle intrusion of monsoon moisture into southern Utah, potentially as early as Thursday. This moisture will allow for the development of a few high based showers and thunderstorms, primarily focused over the higher terrain of southern Utah. Any storms that develop will be capable of producing gusty and erratic downburst winds.

By Sunday into Monday, there is good agreement in guidance that the ridge axis will shift east of the area, becoming centered over the Four Corners. This positioning of the ridge is a typical scenario for a larger surge of monsoon moisture across the forecast area. Thus, there will be decreasing temperatures and increase in the potential for precipitation, with the primary threat over the area, particularly southern Utah, shifting toward flash flooding for at least the first part of the upcoming week.

AVIATION, Issued 706 PM MDT Tue Aug 4 2026...KSLC

Light northerly winds are expected to return to a southerly drainage flow after sunset this evening, with south winds expected to prevail through the overnight hours. An increase in near-surface smoke is anticipated to spread over the airfield early Wednesday morning, with VIS dropping to 5SM or less around 08-09Z. Brief light northerly winds may be possible as this smoke enters the area. This smoke is expected to remain in place through the day tomorrow, with marginal improvements expected after 17Z.

REST OF UTAH AND SOUTHWEST WYOMING...Light diurnally driven flows are expected across Utah and southwest Wyoming this evening, with current breezy west to northwest winds across eastern and southern Utah weakening around 03Z. An area of higher density near-surface smoke is expected to move into northern Utah and southwest Wyoming (from about KSVR/KTVY/KENV northward) this evening, bringing potential MVFR conditions due to VIS restrictions.

FIRE WEATHER

Building high pressure will bring increasing temperatures and generally light winds over the next few days. For much of Utah, the airmass will remain critical dry. However, by Thursday into Friday, a small amount of moisture is expected to advect into southern Utah. This will bring a few showers and thunderstorms over the higher terrain of southern Utah each afternoon, and any storms that develop will have the potential to produce gusty and erratic downburst winds as well as isolated dry lightning. Temperatures become quite unseasonably hot again across the area both Friday and Saturday. By early next week, there is increasing confidence in a surge of monsoon moisture, bringing decreasing temperatures, increasing relative humidities, and a chance of wetting rains.

SLC WATCHES/WARNINGS/ADVISORIES

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