####018006871#### FXUS66 KOTX 041021 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 221 AM PST Thu Dec 4 2025 .KEY MESSAGES... - Wintry mix Thursday into Friday may result in a slick commutes. - Warming temperatures and a transition of snow to rain late this week with breezy winds. - Moderate impacts from snow expected on the mountain passes late week into the weekend. - Increased potential for rock slides next week with a mild and wet weather pattern. && .SYNOPSIS... The weather will trend much more unsettled Thursday through the weekend. Temperatures look to be cold enough tonight into Friday to support a lowland wintry mix. By Friday, temperatures will modify and warm above normal with unsettled weather continuing through the weekend and into next week. && .DISCUSSION... MIXED VALLEY PRECIPITATION AND MOUNTAIN SNOW THROUGH THIS WEEKEND TO BRING THE POTENTIAL FOR TRAVEL IMPACTS... Today through Saturday Night: An active jet stream will be aimed at the region bringing several rounds of precipitation. The first short wave arrives today as warm advection results in isentropic ascent which is maximized over the ID Panhandle, particularly the Central Panhandle Mountains with the assistance of upslope flow as well. Precipitable water increases to 175-200% of normal further increasing confidence of an increase in precipitation. The warm advection will help erode the cold air from southwest to northeast, reaching the Wenatchee and Moses Lake areas and the Waterville Plateau this morning. Temperatures have been holding steady in Wenatchee and Moses Lake around 33-35F, but gain a little elevation onto the Waterville Plateau and temperatures are in the upper 20s. Temperatures are also running colder for the Upper Columbia Basin. With the warming aloft and surface temperatures near freezing, the HREF continues to advertise areas of light freezing rain this morning. Yet, with POP's only chance and amounts expected to be very light confidence in significant impacts for an advisory is low. As precipitation reaches NE Washington into the ID Panhandle, mainly snow is expected, although snow levels will gradually be rising to 2000-2500 feet this afternoon into the evening. A relative lull in the precipitation occurs tonight as the first wave before the next round moves in Friday morning. The latest HREF shows low level cold air to be scrubbed out for mainly a valley rain/mountain snow event except the northern valleys where snow levels will start off around 2000 feet. This wave will carry stronger isentropic lift as warm advection continues with even the northern valleys changing to rain Friday afternoon. There will also be stronger jet support as a robust 160 kt zonal jet takes aim at the region. 850mb winds increase to 50 kts, jet being in the warm sector mixing potential does not look sufficient for these higher gusts to mix down into the valleys. Yet there are a few exceptions. One being around the Wenatchee area and Waterville Plateau where a stable layer above mountain tops may allow stronger gusts to mix down. Another is the Alpowa Summit area near the Blue Mountains, with HRRR currently advertising gusts around 50 MPH. With snow levels on the increase this should limit snow impacts for Stevens Pass as steady light snow today changes to rain tonight. After the strong jet Friday sags south Friday Night snow levels fall back down to near 4000 feet Saturday leading to a better potential for snow to impact the pass. For Lookout Pass precipitation is expected to fall as mainly snow through the evening with a Winter Weather Advisory in effect for the first round of snow today into tonight, followed by a Winter Storm Watch above 3000 feet for Friday. Sunday through Wednesday: A mild and wet pattern continues with rounds of more precipitation. These next rounds look to contain greater moisture content as an atmospheric river takes aim at the region Monday into Tuesday. After that model differ if it continues into Wednesday or lifts north or south of the region. Snow levels rise to 5000 to 7000 feet which means even most of the mountain passes see a change to rain. So concerns will shift to mud and rock slides in steep terrain due to rain and snow melt, and rises on rivers and small streams. At this time no flooding is forecast. JW && .AVIATION... 06Z TAFs: Widespread IFR and MVFR stratus will continue tonight over Central and Northeast Washington and the ID Panhandle. Another round of precipitation moves in between 12z-16z Thursday, bringing rain and snow to the region. The warm advection and precipitation will saturate the boundary layer, with IFR and MVFR conditions expanding to include SE Washington and the Lewiston area. Pockets of light freezing rain are also possible in the Columbia Basin Thursday morning. With KEAT/KMWH holding fairly steady near 34-36F and latest HREF guidance supporting rain as the most likely precip type did not mention FZRA for these sites. .FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence of widespread IFR and MVFR conditions across the region into Thursday. Exception is KEAT where increasing downslope boundary layer winds may help break up the stratus Thursday afternoon. JW ----------------------- 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 34 32 39 35 44 36 / 80 70 90 60 40 30 Coeur d'Alene 35 32 39 35 43 35 / 90 70 100 80 70 60 Pullman 36 33 44 38 44 38 / 100 90 100 90 70 60 Lewiston 39 37 49 41 51 41 / 90 90 100 90 50 50 Colville 36 32 36 33 41 32 / 70 40 90 60 50 30 Sandpoint 35 32 36 33 39 35 / 80 70 100 90 80 70 Kellogg 35 33 40 35 40 37 / 100 90 100 100 90 80 Moses Lake 36 35 43 36 50 36 / 70 50 70 20 10 10 Wenatchee 39 35 47 38 49 37 / 50 50 80 50 30 30 Omak 35 33 38 34 42 33 / 50 40 90 40 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...Winter Weather Advisory from 7 AM this morning to 4 AM PST Friday for Central Panhandle Mountains. Winter Storm Watch from late tonight through Saturday afternoon for Central Panhandle Mountains. && $$ ####018005418#### FXUS63 KABR 041021 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 421 AM CST Thu Dec 4 2025 .KEY MESSAGES... - Downslope winds expected in the Sisseton Hills region today, with gusts from 40-50 mph. This may create areas of blowing/drifting snow. - System late tonight into Friday bringing generally around an inch or less of light snow. - Snow chances (40-60%) return Saturday as a clipper system moves through following by periodic lower chances (20-40%) through early next week as more weather systems have the potential to move through the region. && .SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/... Issued at 420 AM CST Thu Dec 4 2025 Area of stratus (with flurries) continues to advance eastward across the CWA within the warm air advection regime. Warm front will advance eastward across the CWA through the day as 925mb temps rise to around +2C to +3C (HREF mean) across the southwest CWA. Although across the far east, perhaps only -4C to -5C. This still equates to highs in the 20s east, to the low/mid 30s across central SD. Bigger story continues to be the downslope winds expected over the Coteau today. HREF mean continue to indicate gusts 40-45 mph. Probs for 50+ mph do show a small/localized area of 20-40% in the immediate downslope side of the Coteau. Tried to convey these speeds in the forecast over there. PotBlowingSnow output continues with drifting/patchy blowing over the eastern CWA. Focus then shifts to the wave of low pressure moving east-southeast across the area late tonight into Friday. Hi-res output continues to show light snow/light QPF across the region as this wave moves through. There is some variance in the hi-res reflectivity output in just how expansive any pockets/areas of light snow will be. After looking at various snowfall output/probabilities, it appears accumulations will be around an inch or less for most areas. && .LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/... Issued at 420 AM CST Thu Dec 4 2025 The period begins Friday night into Saturday morning with another clipper like low pressure system on our doorstep. The upper wave associated with this system looks to pack a bit more of a punch than the previous one mentioned above. There still some uncertainty in the exact track of this low as model consensus remains within reasonable agreement but also contains some slight differences. Therefore, any slight adjustments in the track of the low will have a big impact on who gets a good dose of snow and who doesn't. With that said, the general agreement is pointing to a track that favors the clipper just off to the southwest of our forecast area. This would mean our southern and western zones may see more of an impact from more snowfall and more wind during the day on Saturday. NBM probabilities of seeing more than 1 inch of snow between early Saturday and early Sunday are between 40-70 percent across our western and southern most zones, while only between 15-30 percent from north central sections of SD into northeast SD and west central MN. For probs of more than 2 inches for the same time frame range between 20-40 percent from east central SD/Watertown area west and south through Clark and Redfield and then down toward the Miller and Kennebec areas, while locales farther north and west of these areas only stand a 5-15 percent chance. Certainly a system we'll have to pay attention to in the next couple days as any changes in track of the low will greatly affect snowfall amounts. The northwesterly upper flow pattern that has been in place will continue to remain in place across the region for the foreseeable future. This will be mean continued periodic visits by more clipper like lows through the region early to middle of next week. Deterministic and ensemble solutions vary widely in the timing and placement of any such waves moving through the region. Therefore, it's more difficult to get into any specific inferences on the weather conditions the CWA experiences Sunday through Wednesday of next week. However, expect things to fall more in line with what we've recently observed and experienced with bouts of snow or a wintry mix along with bouts of arctic temperatures mixed in with warming/melting trends. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1113 PM CST Wed Dec 3 2025 Terminals KABR,KATY,KPIR,KMBG It's a difficult TAF forecast starting out, as limited model guidance shows the MVFR cloud deck over central SD, or if they do the coverage is not as extensive as it has been. It will likely be a battle between fog or the MVFR deck nearing from the west at ABR. At the current time the clouds are forecast to move over ABR around 08Z, with the lower visibilities down to around 2SM staying in a TEMPO group due to the lower probability of occurrence. Farther east at ATY the clouds at their current pace would get there around 13Z. If fog develops, increasing winds out of the south may limit fog to prior to 11Z at both ABR and ATY. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ SHORT TERM...TMT LONG TERM...Vipond AVIATION...06