Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
102 FXUS65 KSLC 050921 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 321 AM MDT Sun Oct 5 2025 .SYNOPSIS...A trailing shortwave behind the exiting Pacific storm system will bring scattered showers to northern Utah and southwest Wyoming as temperatures stay on the cool side. Otherwise, dry conditions will persist for the first half of the week, with temperatures warming back to seasonal normals by midweek. && .SHORT TERM (Through 12Z/6AM Tuesday)...The Pacific storm system that brought substantial precipitation to northern Utah and southwest Wyoming is exiting the area this morning. However, some showers still persist over northern Utah, in particular for the northern Wasatch Front. These showers will tend to diminish during the morning. However, a trailing shortwave will bring additional instability to northern portions of the area, resulting in scattered convection, particularly for areas closer to the Utah/Idaho border, through the afternoon. In the wake of the storm system, temperatures will remain on the cool side, with maxes averaging 10F below seasonal normals. By Monday, a Rex Block pattern is expected to develop off the Pacific coast, with a low situated off the southern California coast and a ridge over the Pacific Northwest. This will bring several days of dry conditions with a gradual warming trend in temperatures. .LONG TERM (After 12Z/6AM Tuesday)...Southwest Wyoming and Utah will be dry with conditions warming much of the week. Ensembles are in good agreement that high pressure to the southeast will retrograde through Friday into the southwest. Temperatures will be around 5F cooler than normal Tuesday. Lows to start the day will be cold enough for freeze conditions for many valleys, not including the urban corridor of northern Utah. Valley highs will generally range from the mid 60s to low 70s. Wednesday and Thursday will be similar, with temperatures warming around 5F each day. As the ridge tracks into the southwest, there will be other storm systems that approach the region. Ensembles are in good agreement on a longwave trough approaching the west coast, which will enhance southwest winds from Wednesday likely into the weekend. The other feature will be remnants of a tropical system. Tropical Storm Priscilla, which is south of Baja California, is forecast to become a hurricane and then back to a tropical storm during the week as it tracks west of Baja California. Ensembles have a range of tracks with this system that would interact with the ridge and longwave trough as it pushes into the southwest. The different tracks make for a range of precipitation totals between ensemble members. Regardless, precipitation probability will pick up Friday into the weekend. Depending on the track and timing of the longwave trough and tropical system, portions of Utah could be in a location for an impressive rain event. && .AVIATION...KSLC...Dry conditions will last through the morning, with around a 30% chance for rain showers from 18-22Z. Light southeast winds will transition to northwest around 18Z. .Rest of Utah and Southwest Wyoming...Scattered rain showers will last through around 00Z for southwest Wyoming and far northern Utah. Winds will be light throughout southwest Wyoming and Utah, generally from the north or northwest. && .FIRE WEATHER...The robust storm system that brought significant precipitation to portions of the state is exiting the area this morning, though showers continue over northern Utah. A trailing shortwave will keep scattered showers going through the afternoon, particularly for areas near the Utah/Idaho border, with dry conditions for central and southern Utah. After that, a Rex Block pattern will keep conditions dry over Utah through at least the middle of the week, with temperatures steadily warming back to near normal for this time of year with light winds. As southwest flow develops late in the wake, moisture is expected to move back in, bringing increasing precipitation chances, particularly for southern Utah. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ SHORT TERM/FIRE WEATHER...Traphagan LONG TERM/AVIATION...Wilson For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity