Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
769 FXUS65 KSLC 172057 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 257 PM MDT Fri Oct 17 2025 .SYNOPSIS...Drier and warmer conditions will build in through the end of the weekend. A grazing storm system will bring an enhancement of winds Sunday. A relatively dry cold front Sunday night into Monday will bring light precipitation to far northern Utah and a cool down for southwest Wyoming and much of Utah. && .DISCUSSION...Conditions have been clearing and drying out as a storm system lifts out of southwest Wyoming and Utah. Moisture associated with that storm system along with partial clearing led to locally dense fog for some northern valleys, including the Cache and Heber valleys. As clouds have diminished, lower levels have dried sufficiently to where fog will be more localized and patchy into Saturday for those valleys. Drier northwest flow will be in place through Saturday. Valley high temperatures will be around 60F for most of Utah, roughly 5F cooler than normal. Mostly clear conditions with light winds will last through the day. Zonal flow will bring warm air advection Sunday. Winds will enhance, strongest for southwest Wyoming, as a longwave trough digs in from the northwest. Ensembles are in good agreement that this will graze to the north, with only light precipitation Sunday into Monday near the Idaho border. Precipitation will be light, likely ranging from a trace-0.1". The cold front will come with a drop in temperatures from the low 70s for many valleys Sunday to around 60F Monday. A ridge will be the main feature to start the week. Temperatures will rebound to the 60s for most northern valleys and 70s for southern valleys Tuesday and Wednesday. Ensembles are in good agreement on a closed low tracking from off the coast of Baja California into the southwest U.S. Wednesday. This will bring a surge of moisture into mainly southern Utah. Moisture content and forcing will be sufficient for at least rain showers, but a significant rain event is not likely. && .AVIATION...KSLC...North to northwest winds will shift to the south to southeast between 02-03Z this evening. Otherwise, VFR conditions will continue through Saturday. .REST OF UTAH AND SOUTHWEST WYOMING...Locally dense fog (LIFR) will develop across the Cache Valley and Heber Valley after midnight and continue through 14-16Z Saturday. Otherwise, mainly diurnal, terrain- driven winds will continue through Saturday. && .FIRE WEATHER...A stable, dry northwest flow has builded into Utah after a storm that brought rain and mountain snow tracked through. Conditions will continue to dry out, with northwest flow transitioning to the west from Saturday to Sunday in response to an incoming storm system. That will bring an enhancement to west winds for the end of the weekend, strongest throughout northeast Utah. Temperatures will warm to around 5-10F warmer than normal. Relative humidity values will only drop into the 30-40% range generally for this portion of the state. The most drying will be in western and southern Utah, with minimum relative humidity values in the teens. The storm system that will bring the enhancement in winds will only graze northern Utah. There will be minimal precipitation, with values from a trace-0.1" near the Idaho border. Although the cold front will be relatively dry, temperatures will be around 10F cooler Monday. Conditions will be dry through the start of the week. Models bring the next surge of moisture into southern Utah Wednesday as a storm system tracks northeast from near the coast of Baja California. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ PUBLIC...Wilson AVIATION...Kruse FIRE WEATHER...Wilson For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity