306 FXUS66 KPDT 060525 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1025 PM PDT Sat Jul 5 2025 .Updated for Aviation... .AVIATION... 06Z TAFS...VFR conditions are expected through the TAF period, with winds generally 10 kts or less. && .PREV DISCUSSION... /issued 402 PM PDT Sat Jul 5 2025/ AVIATION...00z TAFs...VFR conditions expected. Outside of some light high clouds, expect generally clear skies and light, terrain-driven winds less than 12 kts, outside of the usual breeziness at the DLS where gusts could reach 25 kts at times through the early evening. Evans/74 PREV DISCUSSION... /issued 139 PM PDT Sat Jul 5 2025/ SHORT TERM...This afternoon through Monday...The short term will be characterized by calm weather. An upper ridge of high pressure will settle over the region bring hot and dry temperatures across the region. Dry and warming conditions will continue through Monday ahead of a dry cold front. Temperatures will be steadily rising with models todays high temperatures will be in the upper 80s to low 90 across the vast majority of the region with upper 60s to low 70s along the Blues and eastern mountains with 80-100% of the ensembles are in agreement. As we move into Sunday and Monday, models show high temperatures to become more widespread with 80-100% of the raw ensembles showing only the ridges of the mountains remaining below 80 degrees. Forecast HeatRisk ranges from Moderate (level 2 of 3) on Monday. LONG TERM...Models are showing an upper level dry cold front making its way into the PacNW Tuesday. Tuesday is set to be the hottest day of the long term with models showing temperatures cresting 100-105 through the Columbia Basin, Yakima Valley and along the foothills of the Northern Blues of OR & WA. Ensembles show 80-100% agreement that the aforementioned area will see these temperatures. Forecast HeatRisk ranges on Tuesday to Major (level 3 of 4). This level of heat would support Heat Advisories for the Yakima/Kittitas valleys, lower Columbia Basin, and foothills of the northern Blue Mountains on Tuesday. Overnight lows from Monday into Tuesday still range low to moderate leading to the potential for heat advisories. With the incoming dry cold front, models are showing an increase in stability as it pushes inland. Ensembles are showing 75-80% probabilities of the southern portion of the CWA from Deschutes county and across the eastern mountains into Wallowa County seeing the potential for thunderstorms Tuesday. Models and ensembles surface CAPE values between 200-500 J/kg,lapse rates over 9C/km and LIs of -2. Looking at dry thunderstorm probabilities, ensembles show 10% probabilities in the southern portion of Deschutes, Crook and Grant Counties. 12 hour probabilities of thunder is a bit higher with 15%. Looking at the model derived sounding, the PWATs are a bit high at 0.53 inches of precipitable water within the mix. We cannot rule out the probability that any storm produced will be dry in nature. The remainder of the long term will be continued dry and warm. Also, with the arrival of the cold front, winds through the Cascade Gaps will increase. The Gorge on Tuesday will likely see winds increasing to near 20 mph with gusts to 30 mph with 40-60% of the ensembles in agreement. Kittitas Valley will also see an increase in the winds ahead of the front with sustained winds of 20 with gusts to 30 mph with 60-70% of the ensembles in agreement. Bennese/90 FIRE WEATHER...Though there will be hot and dry conditions through the forecast period, no fire weather concerns are present through Monday. With that said, the incoming potential for thunderstorms Tuesday will be closely monitored for any fire weather products needed. Bennese/90 && .PRELIMINARY POINT TEMPS/POPS... PDT 56 90 58 98 / 0 0 0 0 ALW 59 89 63 96 / 0 0 0 0 PSC 56 91 59 98 / 0 0 0 0 YKM 57 90 61 96 / 0 0 0 0 HRI 57 92 59 99 / 0 0 0 0 ELN 57 89 59 96 / 0 0 0 0 RDM 45 88 49 96 / 0 0 0 0 LGD 52 86 55 93 / 0 0 0 0 GCD 50 88 54 96 / 0 0 0 0 DLS 57 90 62 98 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...90 LONG TERM....90 AVIATION...77