Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
719 FXUS66 KPDT 021729 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1029 AM PDT Wed Jul 2 2025 .UPDATED AVIATION DISCUSSION... .AVIATION...18Z TAFs...VFR conditions will prevail through this TAF period. All sites may have sustained winds of 12-20kts with gusts at 20-30kts throughout the day (>50% confidence). Winds should decrease to 12kts or less this evening, with an exception of KDLS having gusty winds lasting longer. Feaster/97 && .PREV DISCUSSION... /issued 918 PM PDT Tue Jul 1 2025/ UPDATE... Made some minor adjustments to the forecast mainly for pops based on the current radar and latest model guidance. The heat advisory has expired and the red flag warning for today across central Oregon has also expired. PREV DISCUSSION... /issued 451 PM PDT Tue Jul 1 2025/ SHORT TERM...Today through Thursday...The PacNW will be in between the ridging to the north and the cutoff low moving across California. The Heat Advisory continues through this evening for the Basin, Gorge, Yakima/Kittitas Valleys, Simcoe Highlands and north central Oregon, given the upper ridge keeping our today`s temperatures in the low 100s for these areas. The remaining forecast area will be in the 90s, though RHs will mainly be in the teens across the forecast area. And with the Columbia Basin and Kittitas Valley being drier and warmer than other locations, this will elevate critical fire conditions for those specific areas as well heading into Wednesday. With elevated CAPE values (>500 J/Kg), PWATs of 0.80-1 inches and low lapse rates of 6.5-7.0 C/km, we are also looking at thunderstorms this afternoon into this evening with abundant lightning over central OR, John Day Highlands, and John Day Basin, thanks to the upstream intensification influenced from the cutoff low. This allows the Red Flag Warning for Zone OR700 through the evening as well due to abundant lightning from these storms. In addition to that, breezy outflow winds (15-25 mph) will be induced across the Cascade Gaps from the strong surface pressure gradients. However, there is a 30-60% probability of wind gusts exceeding to 30- 35 mph around the Gorge and Kittitas Valley. With persistent warm temps (<90 degrees) and low RHs (<20%), Red Flag Warning has been issued for Wednesday from 2pm to 9pm PDT for the Columbia Basin. Thunderstorms will develop over the eastern mountains Wednesday late morning into evening with the CAMs showing CAPE values becoming slightly modest (500-800 J/Kg) along with decreased PWATs (<0.75 inches). Even though the moisture level remains low, dry lightning can be still be threatening to potential new or ongoing fires. However, these storms should move further eastward out of our area by tomorrow night. Breezy to windy conditions will continue throughout the day tomorrow across the Cascade gaps from the strengthening surface pressure gradients. The raw ensembles suggest a 30-50% prob for gusts exceeding to 40 mph over the Gorge and Kittitas Valley. Winds will begin decreasing later in the evening. Thursday morning should be relatively quiet until evening showers arrive. Temperatures will decrease to the 70s and 80s across the forecast area with RHs gradually recover a bit to the 20s. However, portions of the Yakima Valley, north central OR, and upper part of the Lower Basin may have pockets of low RHs in the teens. But, no critical fire conditions will be anticipated at this time. The Cascade gaps will have breezy winds at 15-25 mph with a 30-40% prob for gusts to reach 30 mph at Kittitas Valley. Feaster/97 LONG TERM...Friday through Tuesday...Light showers will arrive Friday late morning into evening at the eastern mountains with slight chances (<30%) of afternoon thunderstorms. Weak instability (300-800 J/Kg) and low moisture level (<0.10 inches) may inhibit the storms from becoming severe, but CG lightning could be the main threat. Late Friday evening into night, precip activity should be out of the area. Although the Gorge will be gusting at 25-35 mph in the afternoon, the remaining locations will have light winds with occasional breezes. Saturday could have morning showers over the Wallowas but, chances are low (<20%). Starting Saturday afternoon onwards, the weather will be warm and dry with slight breezy winds. Feaster/97 && .PRELIMINARY POINT TEMPS/POPS... PDT 92 57 86 59 / 10 0 0 0 ALW 91 61 86 62 / 10 0 0 0 PSC 96 58 89 59 / 10 0 0 0 YKM 93 57 87 58 / 0 0 0 0 HRI 94 59 89 59 / 10 0 0 0 ELN 88 56 84 57 / 0 0 0 0 RDM 86 46 83 48 / 0 0 0 10 LGD 89 54 84 57 / 20 20 0 10 GCD 91 52 87 54 / 20 20 20 20 DLS 86 59 85 59 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning from 2 PM this afternoon to 9 PM PDT this evening for ORZ691. WA...Red Flag Warning from 2 PM this afternoon to 9 PM PDT this evening for WAZ690-691. && $$ SHORT TERM...97 LONG TERM....97 AVIATION...97