Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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432 FXUS66 KOTX 052154 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 254 PM PDT Sun May 5 2024 .SYNOPSIS... Rain showers will continue across the PacNW into Monday. As the low slides east, conditions will remain cool and showery and breezy. Warmer and drier weather will arrive late next week. Next weekend has the potential to deliver our warmest temperatures of the spring so far. && .DISCUSSION... Tonight through Tuesday: As the Low continues to pass to the South of the Inland Northwest, a deformation band will be stretched North to South over the Eastern Washington. The band will bring shower activity across the region with many locations seeing at least a quarter of an inch of precip. There will be localized areas of higher amounts near 0.3" mainly in Northeast Washington through Monday morning. The probability of at least 0.2" for most of the region is near 80%. The east slope of the Cascades is expected to miss out as the West to East winds keep the band from reaching these areas. With models hinting at enough instability, an isolated thunderstorm is possible in for Northeast WA including Spokane and North ID on Monday afternoon. Winds will be breezy for both Monday and Tuesday as a quick moving cold front pushes through the region behind the exiting Low. Winds on Monday will be strongest in Southeast Washington and the Palouse with a 60% probability of gusts of at least 30 MPH. The rest of the region can expected gusts into the mid 20s. Tuesday winds will be stronger and more widespread across the Columbia Basin. The probability of at least 30 MPH is at least 40%. Strongest winds will again be in the Palouse reaching into the low 40 MPH range. The Cascades valleys could also see gusts near 40 MPH. Winds will calm late Tuesday as the cold front exits. Temperatures for the next couple of days will be 50s to low 60s for highs and 30s and low 40s for overnight lows. Wednesday through Sunday: Ensembles are in decent agreement of a ridge pattern developing along the coast during this period. A dry warmer trend is expected for the period. There will be diminishing mountain shower activity through Wednesday. The warming trend is expected to bring widespread 80 degree temperatures by the weekend. Overnight lows will be in the upper 40s and 50s. /JDC && .AVIATION... 18Z TAFS: The rain band extending from Sandpoint to Spokane to Tri Cities will pivot to the west this afternoon. That should bring several hours of ceiling and visibility improvements to Spokane, Coeur d`Alene, Pullman and Sandpoint. Radar trends and 12z model runs limit the westward progress to about Moses Lake and Grand Coulee. With drier downslope west winds in central WA, confidence is high that Wenatchee, Chelan, and Omak will remain VFR with little to no precipitation. Moses Lake and Ephrata will get some light rain, but may experience enough drying from the west to keep prevailing VFR until the rain band moves eastward this evening. Spokane, Coeur d`Alene, Pullman, and Lewiston can expect ceilings to lower as the band returns in the 00z-05z time frame before it moves east and gusty winds help to break up low ceilings after 06z. /GKoch FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Confidence in ceilings and visibility within the band of rain is low. We are dealing with an axis of mid and low level moisture convergence favoring localized ceiling reductions to 1500 ft or less, but it is a relatively narrow band with a good deal of dry being advected from the west. With a good deal of variability in the MOS and HREF guidance, frequent amendments are anticipated to keep up with the changing conditions. /GKoch ----------------------- 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 40 57 35 59 37 63 / 100 60 20 10 0 0 Coeur d`Alene 40 54 35 55 37 60 / 100 90 40 30 10 0 Pullman 37 52 34 52 35 56 / 100 70 40 20 0 0 Lewiston 45 61 41 59 41 63 / 100 70 40 30 10 0 Colville 37 59 32 59 36 67 / 100 70 40 20 0 0 Sandpoint 40 53 36 53 38 58 / 100 80 50 50 10 10 Kellogg 39 49 36 48 37 54 / 100 80 70 70 20 20 Moses Lake 40 63 38 64 37 71 / 30 30 0 0 0 0 Wenatchee 44 59 41 59 40 69 / 20 30 0 0 0 0 Omak 42 64 36 64 38 72 / 40 20 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$