Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
545 FXUS66 KPDT 261725 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1025 AM PDT Thu Jun 26 2025 .UPDATED AVIATION. .AVIATION...18Z TAFs...VFR conditions persist as clear to mostly clear conditions prevail over the region. Winds are a bit on the breezy side today, as DLS, PDT, ALW initialize with gusts around 20 mph. Winds will stay between 10-15 mph throughout the period for these sites. BDN/RDM will see higher gusts around 20-25 mph starting at 19Z for RDM and 22Z for BDN. No VIS and CIG issues expected as winds drive to mix and keep conditions fairly visible. PREV DISCUSSION... /issued 156 PM PDT Wed Jun 25 2025/ SHORT TERM...Today through Friday...Current satellite and radar imagery show clear skies across the forecast area with few clouds forming over portions of Kittitas and Yakima Valley including John Day Highlands. Thanks to the southwest flow, isolated thunderstorms will develop over the eastern mountains this afternoon through evening. Abundant lightning may be main threat with a 30-50% probability, suggested from HREF 4-hr prob of thunder. CAMs show CAPE values to be about 500-800 J/Kg with the raw ensembles favoring a 30-50% prob for very light showers. That said, it is doubtful for these storms to be severe due to weak instability and lack of moisture support. Showers may linger over the Wallowas tonight before gradually decreasing Thursday. Dry conditions will return Friday. Breezy to locally windy conditions will continue for this period across the Cascade Gaps, influenced from the strong pressure gradients. The raw ensembles suggest a >50% prob for gusts exceeding to 30 mph over the Columbia River Gorge and Kittitas Valley today and tomorrow in the afternoons, but mainly the Gorge for Friday afternoon also. There is a 30-40% chance of gusts at 35 mph as well. Otherwise, winds will remain breezy for the remaining forecast area. Temperatures will remain mainly in the 70s and 80s across majority of the forecast area through this term. However, the Columbia Basin will be in the high 80s and low 90s before slightly cooling by few degrees tomorrow into Friday. RH values continue in recovery through Friday as this weak system passes. Feaster/97 LONG TERM...Saturday through Wednesday...Warm, dry conditions prevail through the weekend before the system arrives Monday and Tuesday. Showers will develop across the Southern Blues and eastern mountains with a slight chance (<30%) of thunderstorms over the high terrains of central OR Monday evening. Severity is less likely due to weak instability and low moisture level, though CG lightning could be threatening. Temperatures remain trending upward into next week with RHs gradually decreasing to the teens and 20s. Sunday onwards, temps will reach into the 90s or higher with Monday and Tuesday being our warmest and driest days of this period with temperatures reaching to the low 100s across the Columbia Basin (>60% confidence). That said, this could potentially raise concerns for critical fire conditions. Heat Risk will remain moderate across most of the forecast area Sunday and beyond, but with portions of the Columbia Basin remaining in pockets of Major Heat Risk Monday and Tuesday. Winds will be light with occasional breezes for this long term period. Feaster/97 && .PRELIMINARY POINT TEMPS/POPS... PDT 83 56 83 55 / 0 10 0 0 ALW 83 59 81 58 / 0 10 0 0 PSC 86 57 85 55 / 0 10 0 0 YKM 82 54 81 54 / 10 10 0 0 HRI 85 57 85 56 / 0 10 0 0 ELN 78 54 76 54 / 10 10 0 0 RDM 80 44 80 44 / 0 0 0 0 LGD 80 52 78 50 / 10 10 0 0 GCD 83 50 81 49 / 0 10 0 0 DLS 78 58 79 57 / 0 10 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...97 LONG TERM....97 AVIATION...95