textproduct: Salt Lake City

KEY MESSAGES

- A cold front will move through the northwestern half of the area through Monday morning before stalling, bringing much cooler temperatures and drier conditions behind it.

- Monsoon moisture will linger over southeast Utah to start the week, bringing continued potential for showers and thunderstorms capable of producing heavy rain that could lead to isolated flash flooding.

- Temperatures rebound to near seasonal normals across the area by midweek with some unsettled conditions continuing, at least for eastern Utah.

DISCUSSION

A Pacific Northwest storm system is making its way into Montana this evening, with its associated cold front near a KENV-KEMM line. The frontal passage has been mostly dry so far, with just a few very isolated cells developing in the vicinity of the boundary. The front will continue slowly southeast overnight before eventually stalling and slowly weakening. The northwestern half of so of the forecast area will see significantly cooler temperatures by tomorrow afternoon, up to 20F below today's highs, and around 10F below seasonal normals.

Across southeastern Utah, earlier showers and thunderstorms have diminished, and the front is expected to slide the axis of deep moisture a bit to the east, resulting in a bit more limited threat of convection tomorrow afternoon. For southern Utah, little change in temperatures is expected ahead of the front, with highs staying near normal for this time of year.

For midweek and beyond, the details of the forecast look a bit murkier than usual, with ensembles showing a good amount of disagreement with regard to the track of the next Pacific Northwest trough, particularly with how far south it might end up later in the week. This would have implications for the amount of moisture in place for western Utah, primarily. For eastern Utah, the deep moisture never goes away, with the axis most likely shifting a bit westward, bringing increasing coverage of afternoon convection.

AVIATION

KSLC...Northwest winds with VFR conditions will prevail through Monday. These winds will remain gusty through roughly 08Z as a cold front continues to push through the area. These gusts will diminish overnight, with winds remaining northwesterly through the day Monday.

REST OF UTAH AND SOUTHWEST WYOMING...VFR conditions will prevail at all TAF sites through the valid period. A cold front crossing northern Utah will switch winds to the northwest as it pushes through the area overnight. These winds will gust in excess of 20 kts at times before diminishing overnight. Lighter winds are expected across northern terminals Monday, while gusty southwest winds develop once again at KCDC and KSGU.

FIRE WEATHER, Issued 1240 PM MDT Sun Sep 13 2026

Widespread gusty southerly winds exist this afternoon as a cold front is slowly tracking in from the northwest. The strongest winds exist across western Utah in advance of this front, with current location of the front draped from SW-NE across the Great Salt Lake. Cooler temperatures and a period of gusty northwest winds will move in behind the frontal passage prior it stalling across central Utah in roughly 24 hours time. South of this front, gusty southwesterly winds will remain in place.

Monsoonal moisture continues to focus across southeastern Utah today, and this trend will continue through early this week. Currently this moisture is most prevalent from FWZ 498 northeast through FWZ 489, and these will be the primary areas for isolated thunderstorms capable of heavy rainfall in the short term. Due to the front moving into central Utah over the next 24 hours, this zone of thunderstorm potential is expected to shift slightly east early week.

A gradual warming trend is expected to begin on Tuesday across the northern half of district, but temperatures are only expected to rebound to near seasonal normals mid/late week. Monsoonal moisture has the potential to spread across much of central/southern portions mid to late week, but confidence remains lower than normal at this time.

SLC WATCHES/WARNINGS/ADVISORIES

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