015 FXUS66 KOTX 251828 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1128 AM PDT Sat Jul 25 2020 SYNOPSIS... High pressure will slowly build back over Eastern Washington and North Idaho this weekend. The heat returns early next week, with highs back into the mid 90s to low 100s for at least Monday and Tuesday. Only a slight cooling trend is expected after that. DISCUSSION... Todays forecast looks fairly quiet with post frontal, dry airmass, lighter terrain driven winds. We are starting to see some smoke from wildfires near Nespelem and one south of Wenatchee show haze and smoke reaching the surface this morning. As the day wears on there should be some thinning of the smoke as it lifts higher in the atmosphere. With high pressure coming into the region it will be easier for smoke to be trapped near surface longer during the day. Otherwise, we'll see a few cumulus clouds today over the mountains with temperatures at or a bit below seasonal normals in the upper 70s to near 90 depending on location. Going forward into Sunday warming will start in earnest as high pressure builds into the region quickly gettng temperatures above normal for this time of year. ...POTENTIALLY DANGEROUS HEAT MONDAY AND TUESDAY... Monday to Friday: Hot conditions mark the start of this period, with potentially dangerous upper 90s and 100s, while limited shower and thunderstorm chances emerge from later Tuesday onward. From Monday to Tuesday the ridge axis centered over the region shifts eastward and a long-wave trough over the Gulf of Alaska starts to drop south. The increased southwest flow will help to ramp up temperatures. Some mid-level disturbances start to ride in on that southwest flow too, passing near the Blues/Camas Prairie to central ID Panhandle region. A weak one, with limited moisture and instability, passes Monday night while slighter better disturbances pass late Tuesday into Wednesday. This will carry the first shower and thunderstorm chances into the aforementioned. The main risk over the central Panhandle stays over far southern Shoshone county Tuesday, before expanding some on Wednesday. At the same time the Gulf of Alaska long-wave trough digs southward to sit off the Pacific Northwest coast. The models are in better agreement this morning in keeping it off the coast than they were at this time yesterday, though it still makes a run at the area toward late Friday (into next Saturday) so that will be monitored for potential convection late next week. But in general this slower solution holds back any significant relief from the heat, with only gradual cooling from Wednesday onward. Only limited shower chances come to the Cascades and along the Canadian border for Thursday and Friday. Lastly look for some increase winds between Tuesday and Friday, especially in the afternoon hours to early evening hours. The most notable are expected near the Cascade gaps, but even there we may only see gusts in the 20-25 mph range. Other areas may see 15-20 mph gusts. Still afternoon RH values in the teens and low 20s are expected much of the period, with a subtle increase in the second half of the week. This combined with winds and the hot temperatures may be of some concern to the fire weather community, especially Tuesday. Though critical thresholds may not be met. /Cote' AVIATION... 12Z TAFS: VFR conditions will continue through for the TAF period with light, mainly terrain driven winds. There will be a more northeast directional trend of light winds especially at COE less than 10 KTS Sunday morning. TC && .PRELIMINARY POINT TEMPS/POPS... Spokane 82 54 90 58 97 62 / 0 0 0 0 0 0 Coeur d'Alene 80 54 88 57 96 60 / 0 0 0 0 0 0 Pullman 79 48 87 55 94 59 / 0 0 0 0 0 0 Lewiston 86 58 94 64 100 68 / 0 0 0 0 0 0 Colville 84 52 92 55 98 58 / 0 0 0 0 0 0 Sandpoint 79 49 87 57 93 59 / 0 0 0 0 0 0 Kellogg 77 52 86 60 93 64 / 0 0 0 0 0 0 Moses Lake 88 54 96 61 102 65 / 0 0 0 0 0 0 Wenatchee 86 61 95 69 101 71 / 0 0 0 0 0 0 Omak 88 61 95 65 101 67 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$