FXUS66 KOTX 071157 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 457 AM PDT Tue May 7 2024 .SYNOPSIS... Expect breezy winds and showery conditions across the Inland Northwest Tuesday. A weak system will bring light rain and cloudy conditions across north Idaho and far eastern Washington on Wednesday as an upper level ridge builds into the region from the west. This will bring warmer and drier weather through the weekend. && .DISCUSSION... Tuesday: A shortwave will move across the region today as an upper level ridge begins to nudge onshore from the west and an upper level closed low remains nearly stationary over the northern Plains. Radar imagery early this morning shows a persistent Puget Sound Convergence Zone providing precipitation to Snoqualmie and Stevens Pass and showers over the Blue Mountains. I don’t expect snow to result in impacts to the roads with road temperatures remaining above freezing. Diurnal showers will be possible across eastern Washington and north Idaho again this afternoon, but warmer air aloft will reduce the overall coverage. Best chances will be in areas of rising terrain where orographic influences will enhance the vertical lift. Winds will be breezy today as a tight west to northwest pressure gradient sets up across the northwest. The strongest gusts will be felt across the lee of the Cascades into the Waterville Plateau and the western Columbia Basin and across the Blues and the Palouse with gusts 30 to 40 mph this afternoon. Wednesday: Ridging will continue to shift inland Tuesday night into Wednesday, ending the afternoon shower activity and breezy winds and beginning an extended period of warm temperatures. A weak impulse associated with the closed low over the Great Plains will rotate into north Idaho from the northeast, but will struggle to make it further west than far eastern Washington due to the ridge. As a result, far eastern Washington and north Idaho will experience cloudy skies and light precipitation Wednesday with warm and dry weather across central Washington. Ridging will continue to shift eastward Wednesday evening with clearing skies across far eastern Washington and north Idaho through the night. /vmt Thursday through Monday: Ridge in place allows for continued dry conditions coupled with a warming trend that peaks for most, if not all, locations over the weekend with widespread 80s Saturday and Sunday. Approx 60 percent of the clusters show a less amplified ridge overhead Monday with the remaining 40 percent showing either a zonal flow or a more progressive southwest flow with the upper level ridge axis positioning well east over Central Montana. This reorientation of the ridge axis positioning Monday will allow for cooler temperatures and possibly some hit and miss mountain and near Cascade crest pops for precip Monday. These warm temperatures will allow mountain snowpack melt to increase flows on many creeks and rivers allowing some to approach bankfull conditions although the threat of river flooding remains very low (less than 10%) across the Inland NW. /Pelatti && .AVIATION... 12Z TAFS: The Inland Northwest will remain under a conditionally unstable upper level trough of lower pressure through Tuesday. Stratus has developed in the Idaho Panhandle and extend out into the Palouse region. Expect MVFR conditions with ceilings down to 2 kft agl. at KPUW and KCOE through the early morning. Tuesday will be another windy day with westerly wind gusts between 20-30 kts across much of the exposed areas of the basin. Diurnally driven showers are expected Tuesday afternoon and isolated to scattered in coverage from KLWS to KCQV and points eastward. Showers will be weaker compared to yesterday, with a less than 10% chance for thunder. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: There is high confidence stratus for far eastern Washington and north Idaho will clear out by the late morning as dry, westerly winds continue across the region. ----------------------- Confidence descriptors: Low - Less than a 30 percent chance Moderate - 30 to 70 percent chance High - Greater than a 70 percent chance For additional probabilistic information for NWS Spokane airports, please refer to the Aviation Dashboard on our webpage: https://www.weather.gov/otx/avndashboard && .PRELIMINARY POINT TEMPS/POPS... Spokane 60 39 65 41 75 46 / 10 10 10 0 0 0 Coeur d'Alene 57 39 62 41 72 45 / 10 10 10 0 0 0 Pullman 53 36 57 38 70 45 / 10 10 10 0 0 0 Lewiston 60 43 63 44 75 50 / 10 10 10 0 0 0 Colville 61 36 70 37 77 43 / 20 10 0 0 0 0 Sandpoint 55 41 62 42 72 45 / 20 10 10 0 0 0 Kellogg 50 39 56 42 70 47 / 30 20 30 0 0 0 Moses Lake 64 37 72 41 80 48 / 0 0 0 0 0 0 Wenatchee 59 40 71 48 79 54 / 0 0 0 0 0 0 Omak 67 38 74 46 82 50 / 10 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$