034 FXUS65 KSLC 110909 AFDSLC Area Forecast Discussion National Weather Service Salt Lake City UT 309 AM MDT Thu Oct 11 2018 .SYNOPSIS...The next in a series of storm systems will impact the area today. A drying and slight warming trend will follow Friday into Saturday. A mostly dry cold front from the north will bring much cooler temperatures to northern and central Utah Sunday into Monday. && .SHORT TERM (Through 00Z Sunday)...A longwave trough continues to encompass the western CONUS early this morning. A shortwave trough noted in water vapor imagery is currently rotating through the southern Great Basin, with the attendant jet nosing into northwest AZ and south central UT per RAP analysis. This coupled with weak low level moisture advection has allowed an area of rain with a few embedded thunderstorms to develop across northern AZ, with this area spreading into south central and southeast UT over the past couple of hours. As such have increased PoPs and QPF through the morning hours primarily for locations east of Highway 89, and along/southeast of Highway 12. Snow levels should remain around or above 8500 feet. As this initial feature weakens and translates east of the area this afternoon, the larger scale trough will begin to shear apart with a couple of weakening waves, including one currently dropping southward through the Snake River Plain of ID, will maintain a chance of valley rain and mountain snow showers across much of the area this afternoon into early evening. Snow levels in the north should run in the 7000-7500 foot range, rising to 8500 feet and above across central and southern Utah. By Friday the forecast area becomes sandwiched between an upper low which becomes cut off along the California coast, and belt of stronger northwest flow across the northern Rockies into the Central Plains. The result will be drying and gradual warming trend Friday into Saturday, although lingering moisture could allow for patchy fog across a few northern valleys such as the Cache and Wasatch Back. .LONG TERM (AFTER 00Z Sunday)... The extended begins with a shortwave diving southward from the Canadian interior and clipping NE Utah/SW Wyoming. Guidance has come into better agreement regarding the track of this feature, and it now looks likely that the coldest airmass of the season (H7 temps around -10C for most of the northern Utah) will advect into the area Sunday. This will result in highs running 10-20 degrees below normal (colder east of the Wasatch) on Sunday as well as the potential for a hard freeze in many valley locations Monday morning. It should be noted that some precipitation is possible in far northeastern portions of the forecast area with the wave passage Saturday PM/Sunday AM, however given the continental origin of the airmass and the grazing nature of the wave do not expect much more than some light snow showers focused on the terrain.. Early next week the west coast ridge builds inland inland commencing the start of a period characterized by dry conditions and warming temperatures. The only (minor) wrinkle in the extended forecast is the potential that a cut-off low pinned south of the ridge could meander in the vicinity of southern Utah towards the middle of next week resulting in some cooling and low-end precip. chances. However, given guidance uncertainties typical with cut-off lows did not account for this (potential) feature in this forecast package. && .AVIATION...VFR conditions are expected to prevail through the day at SLC albeit with periods of showers in the vicinity of the terminal. Expect the bulk of the showers to remain south of the terminal and Cigs largely staying AOA 7k ft, although temporarily lowered Cigs will be possible if a shower passes overhead. Light and variable or light southerly winds are forecast to shift to the north between 17-19Z. && .FIRE WEATHER...A storm system crossing the region today will bring valley rain and mountain snow showers to the area through this evening. The heaviest precipitation is expected across zones 497 and 498 in southern Utah, where isolated thunderstorms will also be possible. In the wake of this system, a drying and slight warming trend is expected Friday into Saturday. A mostly dry cold front from the north is expected to push through the area Saturday night, bringing much cooler temperatures Sunday into Monday. A dry but stable pattern is expected to follow for much of next week. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...None. WY...None. && $$ Seaman/Carr For more information from NOAA's National Weather Service visit... http://weather.gov/saltlakecity For frequently asked questions about the Area Forecast Discussion visit... http://weather.gov/saltlakecity/general/afd_faqs.php