782 FXUS66 KOTX 190447 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 947 PM PDT Mon Oct 18 2021 .SYNOPSIS... Most of the region will remain dry and warm through Tuesday. A period of light rain is possible Wednesday. A wetter pattern is forecast for the Inland Northwest for the end of the week into next weekend, with temperatures cooling closer to normal. && .DISCUSSION... Tonight through Thursday: A split flow has allowed for a col/saddle point to straddle over Eastern Washington and North Idaho tonight into tomorrow with a low pressure system passing through Nevada and the Great Basin having no effect on sensible weather for our area. The col/saddle point pattern is replaced with a southerly flow juxtaposed between a digging troff off the coast and slightly negatively tilted ridging with axis placement over Montana. This evolution allows for sunny skies and the associated dry and fairly warm forecast to remain. Wednesday a low pressure system and its associated frontal features eject out of the trof with a negative tilt. The moisture plume feeding into this Wednesday system shows signs of elongation and some weakening as the system moves through therefore pops for precip remain high Wednesday however precipitation amounts are not very high. Wednesday winds will be somewhat robust with gusts and prevailing from the southwest. The exit of this disturbance Wednesday night followed up with progressive shortwave ridging moving into the area allows for drier weather to move in and allow for a brief break with dry and somewhat weather Thursday. /Pelatti Thursday night through Sunday: After a brief break between systems during the day Thursday, the Pacific Northwest will be in an active and unsettled weather pattern through the weekend into the beginning of the next work week with multiple shortwaves moving through between Thursday night and Monday. Models suggest that this active pattern will possibly extend beyond Monday into later next week as well. Right now what we can expect is multiple rounds of widespread rain and breezy winds. A broad southwest flow aloft will override the typical rain shadow effect, with the Basin forecasted to see decent rainfall through the weekend. Temperatures will gradually cool into mid 50s. While this will feel quite cooler than the beautiful temperatures we've had this past weekend, these temperatures will be right around normal for the end of October. The first system will move in sometime between Thursday night and Friday afternoon. There are still a decent amount of discrepancies between the deterministic models and the ensembles on the timing with about 53% of the model ensembles suggesting a Thursday night into Friday arrival. Models are in pretty good agreement that this system will be accompanied by a healthy plume of moisture with PWATs nearing 200% of normal. Current forecast has been trending warmer with snow levels remaining above 6000 feet for the duration of the event. Later in the weekend details start to become fuzzy as a deep Gulf of Alaska low moves southeastward toward the Pacific Northwest. Models quickly diverge on the possible solutions with some suggesting a second and a potentially third shortwave to spin off this low and move through by late Sunday night. By the time the next workweek arrives, our current forecast suggests the the lowland areas of the Inland Northwest could see 0.40 to 1.00 inches of beneficial rainfall. Higher elevations could see up to 2 inches. Moderate confidence in these specific amounts as there is still a week for models to change, but they are in good agreement on the idea of significantly wetter pattern through the weekend. Since this would occur over the course of a few days, flooding currently doesn't look to be a major issue. vmt && .AVIATION... 06Z TAFS: VFR conditions are expected through 06z Wednesday across the region. Winds will be generally light tonight, and then become easterly near 5-10 kts on Tuesday as a weather system approaches the west coast. This system will begin to spread high clouds into Central Washington by Tuesday evening, otherwise skies are expected to be clear. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 36 65 42 61 37 63 / 0 0 0 30 0 0 Coeur d'Alene 37 65 40 58 38 61 / 0 0 0 30 10 0 Pullman 33 64 40 58 36 62 / 0 0 0 40 10 0 Lewiston 42 68 47 64 44 68 / 0 0 0 40 10 0 Colville 31 66 34 59 32 61 / 0 0 0 40 10 0 Sandpoint 35 60 36 55 36 56 / 0 0 0 40 20 0 Kellogg 41 64 44 60 39 61 / 0 0 0 40 20 0 Moses Lake 33 64 42 61 37 64 / 0 0 0 30 0 0 Wenatchee 42 63 46 59 42 60 / 0 0 10 60 0 10 Omak 38 66 42 60 39 62 / 0 0 0 50 10 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$