FXUS66 KPDT 140506 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1006 PM PDT Thu Jun 13 2024 .UPDATED AVIATION...06Z TAFs...VFR conditions will remain through the forecast period. CIGs are currently SKC with high incoming clouds expected to move in overnight. Winds will remain elevated at DLS/RDM while the remaining TAF sites will see an increase in the winds overnight. Winds will range between 10-15 mph with gusts to 25 mph across the majority of the TAF sites. Winds will decrease at RDM/BDN between 06-08Z before returning at 20Z-21Z respectively. Bennese/90 && PREV DISCUSSION... /issued 222 PM PDT Thu Jun 13 2024/ SHORT TERM...Tonight through Saturday...The upper level ridge pattern over the region today will be shifting to the east overnight and Friday as a closed upper level low pressure system in the Gulf of Alaska moves closer to Vancouver Island Friday. This will begin to tighten the pressure gradient across the forecast area overnight and Friday resulting in some increasing westerly winds. This will mainly be noticeable along the east slopes of the Cascades late this afternoon and into the evening before spreading east into the Columbia Basin overnight providing some breezy conditions which continue through Friday. A wind advisory has been issued for the Kittitas Valley from this evening through Friday morning. The closed upper level low will move over Vancouver Island Friday night into Saturday. This will further tighten pressure gradients across the forecast area increasing winds to 15 to 30 mph with gusts 30-40 mph on Saturday. These speeds would be slightly below advisory level so at this point not considering an advisory but will see how later model runs trend. The low will begin moving some moisture and precipitation into Cascades mainly along the crest Friday night with a 30-50% of showers which increases to 40-80% on Saturday. This moisture will also clip NE Oregon and SE Washington with a low chance of showers (15-30%) on Saturday. The low will pass to the east late Saturday allowing a drier flow to bring an end to the showers overnight. High temperatures will begin to cool slightly on Friday but will become significantly cooler on Saturday with high temperatures running 10 to 15 degrees cooler than normal. LONG TERM...Sunday through Thursday...A challenging start to the forecast period as variations in model solutions starts early. Variances in the track of an incoming of low pressure system leaves a lack of strong confidence in any specific solution. The ensemble clusters for Sunday and Monday highlight the track and strength differences, though all agree that there will be precipitation at some point during the late weekend/early week timeframe. The current NBM solution introduces precipitation over the Cascades by Sunday afternoon, with activity spreading eastward into central Oregon by early Monday morning with the core of the system moving through the forecast area by Monday afternoon. As the system progresses eastward, there is an indication for wrap-around moisture to impact the eastern half of the forecast area. This looks to produce moderate chances (40-60%) over the Blue Mountains and slight to moderate chances (20-40%) across the lower elevations through Monday evening. Winds of 10-15 mph favored with this pattern, with locally higher gusts. Lingering moisture will leave showers possible (20-40% chance) through Tuesday. Northwest flow moves over the region Tuesday evening and remains through Thursday. Remaining moisture/instability could produce a few showers or storms on Wednesday afternoon mainly over the higher terrain (15-25% chance) with dry conditions then generally anticipated through Thursday. Impacts from the initial low pressure system will produce temperatures that are 10-15 degrees below normal on Sunday and Monday. Warmer values return to the region Tuesday through Thursday, with values on Thursday returning to near normal to slightly above normal values. The Columbia Basin is favored to have some of the warmer temperatures on Thursday, with a 70-90% chance for temperatures reaching 80 degrees (10-20% chance of reaching 90 degrees). Branham/76 && .PRELIMINARY POINT TEMPS/POPS... PDT 49 73 48 66 / 0 0 0 10 ALW 51 77 52 69 / 0 0 0 10 PSC 55 80 56 72 / 0 0 0 10 YKM 49 76 47 68 / 0 0 0 10 HRI 53 78 53 71 / 0 0 0 10 ELN 51 69 48 64 / 0 0 0 10 RDM 43 71 41 62 / 0 0 0 0 LGD 46 71 45 62 / 0 0 0 20 GCD 48 75 43 64 / 0 0 0 10 DLS 52 74 52 67 / 0 0 0 20 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...Wind Advisory until 11 AM PDT Friday for WAZ026. && $$ SHORT TERM...91 LONG TERM....76 AVIATION...90