FXUS66 KPDT 201013 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 313 AM PDT Fri Mar 20 2026 .KEY MESSAGES... 1. Cascade rain will persist through today (Friday) 2. Above seasonal average temperatures remain Friday 3. A system will bring temperatures back to seasonal average Saturday with mountain precipitation continuing && .DISCUSSION...Current radar shows a few returns over the WA Cascades as the remnants of the atmospheric river remain over the area. Current ground observations show that the last hour these returns have only put down between 0.10-0.12 inches of rain. Rain is expected to continue over the mountains through today (Friday) with rain accumulations nearing 0.4-0.8 inches through 5 AM (70-90% confidence). Saturday snow levels will begin to drop steadily through Friday and Saturday bottoming out at around 2500 feet. This front will also be bringing cooler temperatures back to the mountains with light high elevation mountain snow with accumulations of 0.10-0.30 inches above 4000 feet (70-90% confidence). Models show an upper level ridge still over the region. This is what is bringing the above average seasonal temperatures. In house comparisons for temperatures shows that temperatures Friday remain anywhere between 20-25 degrees above normal with even the higher elevations seeing above average temperatures. Models show the ridge to remain in place through at least Friday night ahead of a pattern change. Temperatures will remain above seasonal average through Friday with temperatures remaining in the low to mid 70s across the region with 90-100% of the NBM raw ensembles in agreement. Friday temperatures will remain in the mid 70s for much of the region with again 90-100% of the raw ensembles in agreement. Friday night into Saturday models are in firm agreement with a weak upper level trough sweeping into the region followed by zonal flow. NBM shows snow levels to begin to decrease as the system moves across and temperatures will decrease to near seasonal average. Mountain precipitation is expected with this system with very light (0.01-0.03 inches) snow accumulations expected (80-90% confidence) along the crests of the Cascades while lower elevations along the east slopes will see a rain/snow mix. Models show much of the precipitation to primarily along the OR Cascades and the foothills of the Blues and the Blue Mountains Saturday with rain amounts of 0.05-0.10 inches (60-80% confidence). Temperatures will decrease by nearly 20 degrees Saturday with localized highs in the low 60s in the Basin and mid to upper 50s elsewhere (70-80% confidence). && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... VFR conditions will prevail through the forecast period. High pressure remains overhead so CIGs will be mostly 10kft and higher. Winds will be the primary concern through the period as all sites will see sustained winds of 10-20 kts sustained with gusts 20-30 kts after 17-20Z. Winds will ease Friday night to less than 12 kts. 90 && .FIRE WEATHER...An SPS is out for elevated fire weather conditions for Ochoco-John Day Highlands and central OR. A strong ridge of high pressure has lead to well above average seasonal temperatures as well as very low relative humidities (80-90% confidence)for portions of central OR and the eastern mountains. Additionally, diurnal winds have the capabilities of reaching 20 to 30 mph gusts (50-70% confidence). The combination of dry conditions and elevated winds can lead to rapid fire spread. 90 && .Preliminary Point Temps/PoPs... PDT 75 46 58 31 / 10 40 40 0 ALW 74 48 59 35 / 10 50 60 0 PSC 76 47 64 34 / 10 30 20 0 YKM 71 41 59 30 / 30 20 0 0 HRI 76 48 63 32 / 10 30 20 0 ELN 60 37 51 29 / 50 20 0 0 RDM 76 43 58 24 / 0 10 10 0 LGD 78 45 56 29 / 0 30 70 10 GCD 77 46 56 29 / 0 10 50 0 DLS 70 46 60 34 / 20 30 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...90 AVIATION...90 FIRE WEATHER...90