textproduct: Salt Lake City

KEY MESSAGES, Issued 1050 AM MDT Tue Jul 7 2026

- High based showers and thunderstorms will develop over northern Utah and southwest Wyoming late this afternoon into the evening, with any storms that develop capable of producing strong to severe wind gusts, with the threat returning Wednesday afternoon and evening.

- Gusty winds and low relative humidity will combine to produce areas of critical fire weather conditions over some southern Utah valleys this afternoon. The threat of critical fire weather conditions will expand into the mountains of southern Utah for Wednesday.

- There is increasing confidence that a notable heat wave will develop over the weekend, with many valleys forecast to see HeatRisk values in the red (major) range, and some northern Utah valleys seeing values in the purple (extreme) range Saturday into Sunday.

DISCUSSION, Issued 1050 AM MDT Tue Jul 7 2026

A broad area of high pressure is centered over the central United States this morning, with Utah and southwest Wyoming under a breezy southwest flow on the back side of this feature, enhanced by some shortwave energy moving over the top of the ridge. Highs today will be similar to yesterday, with maxes running up to 5F above seasonal normals. Though the southwest flow is drawing some moisture northward, relative humidities will still be low enough in some valleys of southern Utah to combine with the breezy winds to result in areas of critical fire weather conditions.

Guidance continues to indicate a setup favorable for another round of strong to severe convection for northern Utah and southwest Wyoming this afternoon. A shortwave is expected to move over northern portions of the area late this afternoon into the early evening with some decent jet support providing upper level divergence. Combined with anticipated bulk effective shear of 30-40 kts, this has the potential to bring a bit of more organized convection. Given the high based nature of these storms, primary threat will be strong, gusty outflow winds and isolated dry lightning. However, cannot rule out some hail. Overall, have increased POPs a bit over northern Utah to account for the threat and extended the mentionable POPs into the first part of the overnight hours given model trends.

With the central US ridge expected to weaken tomorrow, the flow aloft over the area is expected to have more of a westerly component, tapping into a dry slot over the California coast. This will drop relative humidities from southwest to northeast over the forecast area, resulting in more widespread critical fire weather conditions as winds remain elevated. Some moisture will remain over parts of northern Utah and southwest Wyoming, with more shortwave energy expected to move through during the late afternoon and early evening once again. This feature looks better defined than the one expected today, with a weak boundary in association with it, so if anything seeing better dynamics for tomorrow compared to today, though the main threat will shift slightly farther north.

Drier air is expected to continue to move in through the remainder of the work week. By Friday, a ridge centered near southern Nevada will start to expand, before the axis shifts overhead Saturday and east of the area on Sunday. There is high confidence that this will bring some of the hottest temperatures of the season so far, particularly for northern Utah and southwest Wyoming. HeatRisk forecasts show red (major) values for many valleys across the area, with perhaps the exception of the lowest southern Utah valleys. By Sunday, there is an increasing chance of purple (extreme) HeatRisk values for some northern Utah valleys, including the Cache Valley and Wasatch Front. There is high confidence that these highs will challenge at least daily records, with some guidance indicating monthly records, and, in the case of Logan, all-time records will be in play. Predictably, this will significantly increase the chance of heat related illnesses across the area over the upcoming weekend.

As the ridge continues east of the area early next week, there is increasing confidence that temperatures will move from extremely hot to just hot, with guidance showing highs "just" 5-10F above seasonal normals by day seven. Increasing southerly flow could also bring a return of moisture by the middle of next week.

AVIATION, Issued 1157 AM MDT Tue Jul 7 2026

KSLC...There is a low (~20%) chance that a few thunderstorms will develop over the Oquirrhs and drift over the terminal between 19-22z this afternoon. These storms will be capable of producing a brief period of gusty and erratic outflow winds in excess of 25-30kts. Outside of this, expect northwesterly winds to persist through the afternoon. Outflow from storms over northwestern Utah arriving around 03-04z is likely to produce a couple hours of gusty northwesterly winds up to 20-30kts.

REST OF UTAH AND SOUTHWEST WYOMING...Scattered showers and thunderstorms will develop once again this afternoon across two main areas: northwestern Utah and across areas east of roughly KEVW-KHCR- KBCE. Outside of these areas, isolated storms may still develop across higher terrain, but will be weaker overall. Still, any thunderstorms will be capable of producing gusty and erratic outflow winds. VFR conditions will prevail.

FIRE WEATHER

Showers and a few thunderstorms have developed this afternoon over portions of northern and eastern Utah. These storms will be high-based, particularly for northern Utah, and will bring the threat of isolated dry lightning into the early evening. Meanwhile, breezy southerly winds will combine with continued dry conditions over the valleys of southern Utah to produce areas of critical fire weather conditions. A drying trend will begin Wednesday, lasting through the upcoming weekend. With breezy conditions persisting, much of central and southern Utah will see areas of critical fire weather conditions for Wednesday before winds decrease for Thursday. Strong high pressure will build for the upcoming weekend, bringing very dry conditions and the potential for record breaking heat by Sunday. Conditions will become less hot to start the work week, with the potential for moisture to return by the middle of next week.

SLC WATCHES/WARNINGS/ADVISORIES

UT...Red Flag Warning until 9 PM MDT Wednesday for UTZ492-495-497-498.

Red Flag Warning from noon to 9 PM MDT Wednesday for UTZ493-496.

WY...None.