textproduct: Salt Lake City

KEY MESSAGES, Issued 1025 PM MDT Sun Sep 13 2026

- 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, Issued 1025 PM MDT Sun Sep 13 2026

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, Issued 1025 PM MDT Sun Sep 13 2026

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

A dry cold front continues track south into central Utah early this morning. The font will wash out in place across central Utah today. This will make for a dichotomy across Utah, with cooler, drier conditions in place across Northern Utah today, while Southern Utah remains warm and with higher humidity in place Isolated showers and thunderstorms are yet again possible across southern, but mainly far southeastern Utah today.

Southerly flow across the state quickly redevelops Tuesday into Wednesday ushering back in warmer and moister conditions across more of the state (except for the far west and northwestern portions of the area, which will remain on the edge of that moisture push). Thus scattered shower and thunderstorm potential will increase again Tuesday and Wednesday, with the better confidence in higher moisture and shower/thunderstorm potential mainly east of the I-15 corridor.

SLC WATCHES/WARNINGS/ADVISORIES

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