Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
653 FXUS65 KSLC 182136 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 336 PM MDT Wed Sep 18 2024 .SYNOPSIS...Stable conditions remain in place across the region with temperatures returning to near, or slightly below, normal on Thursday. Dry conditions prevail until Friday/ Saturday as an upper low moves across the southwest region and brings low to medium chances for light precipitation for portions of Utah. && .SHORT TERM (Through 12Z/6AM Friday)...Quiet weather conditions exist across the region today as we find Utah and southwest Wyoming in the stable wake of a departing cold storm system. Cool temperatures with highs around 5 to 10 degrees below seasonal normals have been observed across the region, with clouds mainly tied to the terrain features across Utah. An upstream upper low, currently noted over central California, will be our next "significant" weather feature toward the end of the week. Until this feature arrives, shortwave ridging between the departing storm and the upstream storm will prevail and bring stable conditions. This environment will favor largely clear skies across the region, light winds, and warming temperatures. Though temperatures are expected to warm by 2-5 degrees across the forecast area, this will still keep high temperatures at, or just below, seasonal normals for this time of year. All in all, it`s going to be a great day for weather on Thursday. The aforementioned upper low will begin progressing into the region through the late evening and overnight hours leading into Friday. While moisture lacks and significant forcing will be farther to the south of the forecast area, not expecting any widespread precipitation through the overnight hours. That said, there are a couple of larger scale features that may assist with some light forcing for rising air which will bring a low probability for isolated light rain showers in southwestern Utah overnight Thursday into Friday. Little to no precipitation will be expected, mainly just high based virga. .LONG TERM (After 12Z/6AM Friday), Issued 336 AM MDT... The long term period will be seasonal and pleasant making for great opportunities to experience the quickly changing fall foliage. A weakening cutoff low will be moving through northern Arizona on Friday and Saturday. This will result in some diurnal showers mainly over the terrain of central and southern Utah, but amounting to little QPF totals (generally <0.1"). Temperatures will remain near normal across northern Utah/SW Wyoming while southern and central Utah will be a few degrees below normal. This low exits to the east on Saturday with some lingering light showers possible across the terrain. Beyond this low, we will remain in a light westerly/northwesterly flow regime that will keep temperatures near normal with a rogue shortwave remaining possible. Ensemble guidance is in agreement with a ridge building across the western CONUS by next week that should help warm temperatures slightly and keep conditions mostly dry. && .AVIATION...KSLC...The SLC terminal will see VFR conditions through the evening with mostly clear skies. Northwest winds are expected to shift to the southeast between 03Z and 05Z. .REST OF UTAH AND SOUTHWEST WYOMING...The airspace will see VFR conditions through the evening with some scattered clouds this afternoon over the higher terrain. Winds will be generally light and terrain driven through the valid TAF period. && .FIRE WEATHER...Dry and relatively stable conditions will remain in place across Utah through Thursday as we find ourselves between two areas of low pressure. Winds are expected to be generally light and terrain driven across the region, with prevailing large scale winds out of the south to southwest. A weak area of low pressure, passing primarily to the south, will bring an increase in moisture to the area on Friday and bring increasing afternoon humidity trends, little change in temperatures, and generally light precipitation. There will be a low end chance for an isolated thunderstorm on Friday afternoon, with little precipitation expected from individual storms. Chances for wetting rains will be less than 20 percent across Utah. Rain chances linger through Saturday afternoon, primarily across the eastern half of Utah. High pressure is anticipated to reestablish across the region by early to middle of next week, bringing a warming and drying trend across Utah. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ SHORT TERM...Webber LONG TERM...Mahan AVIATION...Traphagan FIRE WEATHER...Webber For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity