018 FXUS66 KOTX 230903 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 203 AM PDT Tue Jul 23 2019 .SYNOPSIS... Temperatures today will likely reach the 90s. There will be an increasing risk for thunderstorms...especially tonight. A cold front passage will moderate temperatures back to near normal Wednesday, but will bring with it breezy winds. Dry and seasonably warm conditions are expected for the end of the work week and through next weekend. && .DISCUSSION... Today and tonight: An active period is in store tonight as a strong negative tilt trough and cold front pass through the region. Today: Relatively quiet conditions are expected through the afternoon as monsoon moisture coming up from the south tracks mainly to our south and east across Central Idaho and SW Montana. Models indicate quite a bit of instability over the Blue Mountains into the Idaho Panhandle this afternoon but there should be sufficient convective inhibition (50-100 J/KG) to prevent strong surface based convection from forming. Could see a few elevated storms develop late afternoon around the Blue Mountains, Camas Prairie, and Central Panhandle Mountains. The main threat of showers as well as potentially a few thunderstorms will be in the Cascades with the approaching upper trough. Away from the Cascades skies are expected to be mostly sunny with 850mb temperatures warming to 23-26C yielding widespread highs in the 90s. Tonight: Showers and thunderstorms will be on the increase this evening as a slug of monsoonal moisture across Eastern Oregon gets pulled north into Eastern WA/N Idaho. In addition large scale lift will be increasing with the incoming trough. Elevated CAPE of 300-600 J/KG is progged from the past couple NAM model runs east of a line from Hanford to Republic where the best threat of thunderstorms is expected although isolated thunderstorms are also possible in the Cascades and Okanogan/Methow Valleys. While the storms will be quick moving tonight, the moist atmosphere and strong atmospheric lift should promote locally moderate rain. Models show the potential for a tenth to quarter inch of rain with locally higher amounts across NE Washington valleys and mountains. The fast moving nature of the storms across the Columbia Basin, Spokane area, and Palouse should limit rain amounts to less than a tenth of an inch for most locations where the Fire Weather Watch will be upgraded to a Red Flag Warning where new fire starts from lightning are possible. And with any new fire starts, winds are a concern. 850mb winds increase to 25-35 kts with and behind the front passage which combined with strong cold advection will result in breezy to windy conditions. This may promote fire spread for any grass/brush fuels that receive little to no rain. JW Wednesday...By Wednesday morning the upper trough axis will be hooking out of the area into Montana and Alberta. Some residual showers and possibly leftover thunderstorms will impact the far northeastern zones during the early morning hours but by afternoon a sharply building follow-on short wave ridge will stabilize the atmosphere for no further precipitation. The main issue on Wednesday will be winds and dry conditions despite significantly cooler temperatures. Strong cool advection in the wake of the cold front invading the basin through the Cascade gaps will promote solidly breezy and gusty conditions across the region. The strongest wind potential will be in the morning and early afternoon with locations near the Cascades with sustained winds in the 20 mph range with gusts into the 30 to 40 mph range...with a general 15 to 20 mph with gusts to 30 or so over the open range of the eastern and central basin as well as south exposure higher terrain north of the basin. Temperatures will be a good 10 to 15 degrees cooler on Wednesday than today...but dew points will plunge into the 30s from the current 40s and lower 50s. This will produce quite dry conditions and the the potential exists for rapid fire spread in the range lands of the open basin despite the cooler air mass. Wednesday night through Monday...Models are in good agreement in advertising a rather progressive flow regime over the region through the remainder of the week and through next weekend featuring flat short wave ridges or zonal flow punctuated by a few weak short wave passages which will probably manifest themselves as dry cold fronts...one currently expected on or about Friday night and another possibly on or about Monday. This flow regime will prevent any significant warm ups...with Friday just ahead of the next short wave possibly the warmest day with high temperatures popping a little above average before moderating back to near average (generally the mid to upper 80s for this time of year) with plenty of sunshine but breezy winds at time particularly near the Cascade gaps. /Fugazzi && .AVIATION... 06Z TAFS: A weak shortwave lifts in tonight, with limited shower chances over SE WA/lower ID (PUW/LWS/COE) and even smaller risk for t-storms tonight, with the threat of mainly sprinkles elsewhere. A stronger system starts to move in late Tuesday, increasing the threat of thunderstorms in the Cascades and southeast WA/lower ID again in the afternoon, though the better risk develops after 00Z near EAT, MWH near 03Z and near GEG-SFF- COE-PUW-LWS between 03-06Z (and after). These will may be strong with brief heavy rain, gusty winds and a threat of hail. Outside of t-storms, however, primarily VFR conditions are expected. /Cote' && .PRELIMINARY POINT TEMPS/POPS... Spokane 94 58 79 52 85 55 / 0 70 0 0 0 0 Coeur d'Alene 95 58 77 52 83 54 / 0 70 10 0 0 0 Pullman 91 55 76 48 83 52 / 10 40 0 0 0 0 Lewiston 99 64 84 57 91 62 / 10 30 0 0 0 0 Colville 99 59 83 45 88 47 / 10 80 50 0 0 0 Sandpoint 94 59 76 49 82 52 / 0 80 20 0 0 0 Kellogg 93 57 74 54 81 56 / 10 60 10 0 0 0 Moses Lake 96 60 86 53 91 58 / 0 50 0 0 0 0 Wenatchee 92 62 83 58 89 64 / 10 20 0 0 0 0 Omak 94 60 84 55 89 60 / 10 40 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...Red Flag Warning from 6 PM this evening to 5 AM PDT Wednesday for East Washington Northern Columbia Basin (Zone 673)-East Washington Palouse and Spokane Area (Zone 674). && $$