Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
932 FXUS66 KPDT 160512 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1012 PM PDT Sun Jun 15 2025 .UPDATED AVIATION...06Z TAFs...VFR conditions are forecast for the next 24 hrs. Winds will be diurnally driven until Monday afternoon with DLS/PDT/RDM/BDN will see an increase in winds starting around 15Z for DLS and 21Z for the remaining sites. CIGs will slowly filter in as the system begins to edge towards the region bringing high clouds 20kft OVC/BKN transitioning to SCT/FEW in the morning. Bennese/90 && .PREV DISCUSSION... /issued 649 PM PDT Sun Jun 15 2025/ UPDATE...After collaboration, the evening shift has issued a Red Flag Warning for the Kittitas Valley, valid 2 PM to 9 PM PDT Monday, due to anticipated sustained northwest winds of 20-30 mph and gusts up to 40 mph coupled with low relative humidity of 10-20 percent. Plunkett/86 PREV DISCUSSION... /issued 129 PM PDT Sun Jun 15 2025/ SHORT TERM...Today through Tuesday...Clear skies prevail across the forecast area this afternoon as weak SW flow prevails aloft. Monday will kick off a more active pattern through the weak as an upper- level trough lifts through the PacNW, leaving us with gusty conditions, showers and isolated thunderstorms across the eastern mountains, and potentially critical fire weather conditions for portions of our Cascade Gaps zones. Once this trough passes through heading into Tuesday, drier weather will return, but the winds will be pretty relentless through the rest of the work week as we remain in an amplified wind pattern aloft. Not much to speak of today, as most of the sensible weather concerns in the short term fall on Monday. An upper-level trough, which is relatively starved of moisture, will provide some light shower activity across our far eastern mountains, namely for the Strawberries up through the Wallowas, with a possible isolated storm embedded around the area. There is some supportive instability across the high mountains, but CAMs are pretty gun shy in depicting anything of too much substance tomorrow afternoon. That being said, will leave at least slight chance to chance PoPs for the area, with the expectation that at least a few lightning strikes could formulate from this system. Bigger concern will be the winds from this system as pressure gradients tighten. Models key in on a 7-8 mb cross-Cascade pressure gradient, which would be supportive of wind gusts reaching up to 40 mph across the Cascade Gaps, and 20-30 mph into the Basin. Think there will be enough of a moisture push into the Gorge from this southwesterly system, but the Kittitas Valley could be more borderline for critical fire weather conditions with drier air in place. Will leave later shifts to make an ultimate decision, but will nonetheless highlight the potential for red flag conditions for Kittitas tomorrow afternoon. Winds will back off a bit on Tuesday, but will otherwise remain elevated through the Cascade Gaps thanks to this persistent weather pattern, leaving us with amplified winds aloft. Evans/74 LONG TERM...Wednesday through Sunday...Little will change in the synoptic pattern until the low pressure system, based in the Gulf of Alaska, that is ultimately driving this amplified flow pattern starts to push onshore by around Friday. Of this, ensembles are in pretty good agreement, which will not only provide for more widespread chances for showers across the forecast area, but also a boost in RH recoveries which should (hopefully) aid in any firefighting efforts across the forecast area. Until then, gusty conditions will remain in place through the Kittitas Valley and Columbia River Gorge, picking up again Wednesday afternoon with gusts up to 40 mph and gusts in the 20-30 mph range for the Basin as a jet max circulates overhead on the leading edge of the aforementioned low. Once the low moves onshore, we`ll see yet another round of elevated winds, but this will at least coincide with a rise in RHs as this system brings in a cooler air mass. Evans/74 && .PRELIMINARY POINT TEMPS/POPS... PDT 54 86 51 84 / 0 0 0 0 ALW 59 85 56 83 / 0 0 0 0 PSC 53 90 53 87 / 0 0 0 0 YKM 54 88 51 86 / 0 0 0 0 HRI 53 89 53 87 / 0 0 0 0 ELN 53 84 52 82 / 0 0 0 0 RDM 46 80 39 82 / 0 0 0 0 LGD 54 80 47 81 / 0 20 10 0 GCD 54 82 46 84 / 0 30 10 0 DLS 55 80 53 82 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...Red Flag Warning from 2 PM to 9 PM PDT Monday for WAZ690. && $$ SHORT TERM...74 LONG TERM....74 AVIATION...90