Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
259 FXUS65 KSLC 052049 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 249 PM MDT Sat Jul 5 2025 .SYNOPSIS...A building ridge will favor generally dry and increasingly mild conditions through the middle of the upcoming week, with temperatures currently expected to peak on Wednesday. && .SHORT TERM (Through 12Z/6AM Monday)...Forecast region remains placed within southwesterly flow as a result of a trough translating eastward through MT/ID and a ridge extending into the Four Corners region. Moisture has largely scoured out of the area, though just enough is lingering to result in some building cumulus over the high terrain, especially the Uintas. With diurnal heating ongoing, could still see a couple widely isolated showers try to develop off the terrain, but anticipate most places remain dry. Otherwise, a much quieter day today with temperatures running near to just a slight bit above climatological normal. Synoptically, little changes locally for Sunday. The ID/MT trough will be departing further eastward, but a cutoff low off the California coast in combination with ridging into the Four Corners region will help maintain a similar flow pattern overhead. Some models do carry just a tiny bit of moisture up around the ridge, with CAMs in turn showing a low end chance of a few widely isolated showers developing once again primarily off the terrain during the afternoon hours. Given the dry low levels, could see some modest outflow gusts if something forms, but coverage will be quite minimal at best. Given ultimately little change in the forecast pattern, temperatures will also change little for Sunday, with forecast highs very near Saturday`s peak. .LONG TERM (After 12Z Monday), Issued 404 AM MDT... By Monday, our region will find itself wedged between a closed low retrograding off the coast of California and an area of high pressure building into the Four Corners region. This pattern will provide a weak moisture push into southern Utah, with PWATs locally as high as 0.6-0.7". While these values are quite meager, efficient daytime heating may provide enough forcing for some isolated thunderstorms to develop across the higher terrain across southern Utah on Monday afternoon. Otherwise, dry conditions prevail across the remainder of the forecast area on Monday , with the building high pressure resulting in temperatures climbing back above seasonal averages. A ridge becomes the dominant feature across the western US through at least mid-week, allowing temperatures to continue an upward trend, reaching around 5-8 degrees above normal on Wednesday. Widespread areas of Moderate and locally Major HeatRisk is expected on Tuesday and Wednesday. Ensembles are now in a toss-up regarding the pattern from Thursday onward. Recent guidance now suggests the potential for a shortwave trough to flatten the ridge on Thursday, which would result in more zonal flow over the area and thus moderate temperatures closer to normal. At this point, there is considerable uncertainty in this portion of the long range forecast given the wider envelope of scenarios. && .AVIATION...KSLC...Winds remain southeasterly this morning through around 18z, becoming northwesterly thereafter. Clear skies and dry conditions under building high pressure will maintain VFR conditions through the remainder of the TAF period. .REST OF UTAH AND SOUTHWEST WYOMING...Building high pressure over the region will support continued VFR conditions for all regional terminals through the TAF period. Increased southwesterly winds are expected this afternoon, with gusts 20 to 25 kts across southwest Utah and southwest Wyoming terminals. && .FIRE WEATHER...High pressure is forecast to build over the Four Corners region Sunday and expected to meander through at least midweek. Additionally, a low pressure system situated off the California coast will aid in ushering in southwesterly flow aloft. Within this southwesterly flow, a low-midlevel dry slot will push into the area decreasing RH values areawide through at least midweek. Temperatures will start near-normal at the beginning of the week before increasing to around 5-10 degrees above normal Tuesday and Wednesday as the ridge strengthens. Thankfully, with strong ridging in place, winds are expected to be light throughout the upcoming week. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ SHORT TERM...Warthen LONG TERM...Whitlam AVIATION...Worster FIRE WEATHER...Worster For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity