Area Forecast Discussion
Issued by NWS Salt Lake City, UT
Issued by NWS Salt Lake City, UT
369 FXUS65 KSLC 192134 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 334 PM MDT Mon May 19 2025 .SYNOPSIS...As a system continues to depart Monday, conditions trend drier and milder through the week, though a couple of weaker systems will graze northern areas of the forecast region. && .SHORT TERM (Through 12Z/6AM Wednesday)...Afternoon water vapor loop shows the axis of a broad Pacific trough continuing to shift east of the area. Meager moisture within the trailing northwest flow has resulted in some widely isolated light shower activity, but area radars show coverage has trended down significantly, and forecast models suggest this trend should further continue moving into the evening. Aside from precipitation, this storm brought widespread cool conditions to the area, with afternoon temps currently running about 5F to 15F below climatological normal. Moving into the overnight hours, the cold conditions will persist. With further clearing skies and relaxing winds, conditions will be favorable for effective radiational cooling, and thus will see temps once again get quite chilly. Given the late seasonality to this cold snap, went ahead and upgraded the Freeze Watch to a Freeze Warning for Juab/Millard Counties, the Sanpete Valley, the Sevier Valley, the Western Uinta Basin, and portions of Southwest Utah. The effects/impacts of this cold will be most noticeable to any crops/gardens or other sensitive vegetation. Conditions on Tuesday will warm fairly markedly, with afternoon high marks rebounding to levels near climatological normal. Deeper flow overhead will remain more northwesterly however, and a subtle impulse embedded within faster flow will graze by the northern periphery of the forecast region. As such, will see isolated to scattered shower coverage increase from late morning on through the afternoon hours, primarily along/north of the I-80 corridor, and particularly for areas closer to the UT/ID border. With destabilization leading to mean CAPE values around 100-250 J/kg, a few thunderstorms will also be possible. Given decent boundary layer mixing in some of the forecast CAM soundings with the warmer conditions, expect somewhat dry subcloud layers, and as a result wouldn`t entirely rule out a few marginally strong wind gusts in the 35-50 mph range or so. Overall though, looks like a pretty unremarkable system. Activity clears up Tuesday evening on into the overnight hours, with forecast lows continuing to trend upwards. .LONG TERM (After 12Z/6AM Wednesday), Issued 404 AM MDT... No notable or impactful weather expected through the extended forecast. Temperatures will continue a warming trend Wendesday into Thursday where they will settle on slightly above average values through the weekend and into Monday. Ensemble confidence is increasing that the magnitude of the warm up being driven by a Desert Southwest high ridge will be moderated by an active northern stream jet moving through the Pacific Northwest into Montana. This will keep the ridge suppressed and allow for weak, mainly dry cool fronts at times to sneak into northern Utah, which will help pump the breaks on a more robust warm up. With these brush by systems to our north, cannot rule out an isolated shower late Thursday, and again Saturday and Sunday afternoons, especially over the northern Utah mountains. Other than that, confidence is high in a stretch of dry weather conditions persisting at least into early next week. && .AVIATION....KSLC...West to northwest winds, with gusts around 20 knots, will diminish after 00Z. Light west to northwest winds will prevail through 03Z when winds transition to southeast. Clouds will diminish through the evening, but scattered to broken clouds in VFR range will track in by around 09Z. .REST OF UTAH AND SOUTHWEST WYOMING...West to northwest wind gusts around 20 knots will taper off after 00Z, with relatively light winds after. Clouds will diminish into the evening, but increase for southwest Wyoming and northern Utah after roughly 09Z. Scattered to broken clouds in VFR range will prevail with isolated to scattered rain showers, primarily north of KSLC, from around 12-00Z. && && .FIRE WEATHER...Behind the broad weekend system, conditions will trend drier through the week, as well as milder. That said, will have some weak grazing impulses pass by to the north, bringing lower end precipitation chances to northern Utah Tuesday and Thursday. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...Freeze Warning from 9 PM this evening to 10 AM MDT Tuesday for UTZ114>116-118-119-122. WY...None. && $$ SHORT TERM...Warthen LONG TERM...Church AVIATION...Wilson FIRE WEATHER...Warthen For more information from NOAA`s National Weather Service visit... http://weather.gov/saltlakecity