826 FXUS66 KPDT 250624 AAA AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 958 PM PST Fri Jan 24 2020 updated the aviation discussion .UPDATE...Partly cloudy skies were across the region with a few showers over the area mountains. Otherwise a weather system will move into the western sections of the area tonight with increasing clouds and pcpn along the wa/or cascades. The showers are forecast to move into portions of the columbia basin and central oregon overnight. Snow levels will remain high except for around 3500k to 4k feet in the ochoco highlands toward morning. Minor updates were done to pops and weather and temps that are forecast to fall mostly into the 30s to around 40. .AVIATION...areas of mvfr conditions will develop at all taf sites in response to a weather system moving into the region tonight. Rain showers will lower ceilings and vsby starting at taf site kdls and then all other taf sites after 08z along with lcl ifr conditions. Brief vfr conditions may return after 18z but another weather system will create areas of mvfr mainly after 01z. && .PREV DISCUSSION... .SHORT TERM...Tonight through Sunday night...Portions of the forecast area saw clear skies into the early afternoon, with satellite showing a stream of higher clouds overspreading the area and the next system still well offshore. Westerly flow aloft allowing a steady stream of moisture to come on shore, with radar showing spotty light showers impacting the higher peaks of the Cascades. Tonight, with calmer winds and access to some leftover surface moisture, patchy fog may form in lower elevation areas of the basin, Kittitas/Yakima valleys, and the gorge. Next system tomorrow morning will continue the trend of frontal boundaries moving over the PNW, bringing rounds of rain and mountain snow each day. In this series of weather systems, a surface low will approach the PNW coast Saturday night into Sunday morning, bringing breezy southerly to southwesterly winds as surface pressure gradients bunch up. Snow levels will also drop to 3,500ft-4,000ft by late Sunday night as this system rotates cooler air into the region. Temperatures will be mild through this period, with high temps mostly in the mid 40s to mid 50s. Lawhorn/82 .LONG TERM...Monday through Friday...long term pattern continues to be dominated by deep upper low over near Alaska and ridge over the eastern Pacific extending into the desert southwest. The PacNW is firmly planted in between and multiple fronts/troughs will traverse through the storm track and over the region, bringing multiple rounds of steady rain and high elevation snow. A stronger compact upper low/trough will pass through the region around Tuesday next week with precip building in out ahead of it on Monday and continuing into most of Tuesday. As the system departs Tuesday night, brief transient ridging will bring drier conditions into Wednesday. This will be short-lived as multiple short waves expected to push into the PacNW starting later Wednesday and continuing through the end of week. Snow levels expected to remain well above pass level, but could lower to some higher pass levels early next week behind the departing low/trough, but bulk of precip will have moved out beforehand. Temps running 5-15 degrees above normal with highs in the mid 40s to 50s and lows in the 30s to lower 40s. Locally breezy winds expected with each trough/frontal passage. && .PRELIMINARY POINT TEMPS/POPS... PDT 37 53 42 53 / 10 30 70 70 ALW 39 53 41 54 / 10 30 60 80 PSC 39 50 41 55 / 10 20 70 60 YKM 35 45 37 50 / 30 60 80 60 HRI 39 50 42 55 / 20 20 70 50 ELN 32 41 34 44 / 30 60 80 60 RDM 35 52 39 52 / 30 50 70 40 LGD 33 43 37 46 / 10 40 70 80 GCD 33 47 40 48 / 20 50 80 70 DLS 36 48 42 50 / 40 60 80 70 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 97/97