Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
006 FXUS66 KOTX 290542 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1042 PM PDT Mon Sep 28 2026 .KEY MESSAGES... - Breezy west to southwest winds may result in patchy blowing dust near recently plowed fields Tuesday afternoon. - Mild and dry pattern this week, except for rain near the Cascade crest and chance of rain North Idaho Panhandle on Tuesday. && .SYNOPSIS... Moisture off the Pacific will bring rain to the Cascade crest and northeast Washington and north Idaho mountains on Tuesday. Breezy west to southwest winds may result in patchy blowing dust near recently plowed fields Tuesday afternoon. Temperatures will be near normal through the middle of the week and then trend to above normal for the end of the week and into the weekend. && .DISCUSSION... Today and tonight: An atmospheric river aimed at Vancouver Island and southern British Columbia will sag south over northern Washington into the North ID Panhandle this morning and then remain nearly stationary into the afternoon. Strong westerly flow into the Cascade crest combined with the increase in moisture will result in steady rains into the west slopes of the Cascades, with some precipitation spilling over the crest into the upper reaches of the Methow Valley, Lake Chelan, and Lake Wenatchee. Some dry air initially combined with a strong rain shadow east of the Cascades will result in mainly dry conditions except for areas of light rain in the mountains of NE Washington into the ID Panhandle. This system will also bring in a 130 kt upper jet into southern British Columbia. This will keep our region on the southern, and thus stable side of the jet which will limit our mixing potential. Yet as 850mb winds increase to 20-30 kts out of the southwest windy conditions will occur in the mountains, with breezy winds across the Columbia Basin, Wenatchee Area, Waterville Plateau, West Plains, and Palouse. These winds also have the potential to pick up patchy blowing dust near recently plowed fields. Wednesday through Monday: Models are in good agreement that a transition from westerly flow to a strong upper ridge will occur late in the week bringing about a warming trend. Yet there are a couple of weak waves in the westerly flow that will track through Wednesday and Thursday. The most likely scenario given the lack of lift is for passing mid and high clouds. Yet the NBM is carrying a 20-30 percent chance of lingering light rain Wednesday morning in the Central Panhandle Mountains, and then on Thursday a weak wave bringing a 20-30 percent chance of rain to the Cascades and a 5-10 percent chance elsewhere. Once the ridge strengthens Friday into Saturday confidence increases of the region going into a prolonged warm spell with dry conditions. The latest 6-10 and 8-14 day outlooks from the Climate Prediction Center also support this. JW && .AVIATION... 06Z TAFS: Mid and high clouds will be on the increase tonight due to an arrival of moisten laden westerly 500mb jet. The strong westerly flow across the Cascades tonight into Tuesday will promote lee waves and favorable pattern for turbulence with gusty winds surfacing in the lowlands by Tuesday afternoon. The Cascade crest will likely experience widespread mtn obscurations Tuesday as well with steady precipitaiton. JW FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for VFR conditions at all TAF sites through Tuesday. ----------------------- 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 45 66 46 67 44 68 / 0 20 10 0 0 10 Coeur d`Alene 43 62 49 65 43 66 / 0 20 10 10 0 10 Pullman 42 66 47 65 42 68 / 0 0 10 0 0 0 Lewiston 46 74 53 70 47 73 / 0 0 10 0 0 0 Colville 41 65 38 66 36 68 / 0 10 10 0 0 0 Sandpoint 41 61 43 64 40 65 / 0 30 20 10 0 10 Kellogg 42 60 48 62 44 65 / 0 10 30 20 0 10 Moses Lake 46 72 45 70 44 71 / 0 10 10 0 0 0 Wenatchee 50 69 50 68 52 69 / 0 20 10 0 0 10 Omak 48 66 41 68 42 69 / 0 10 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$