490 FXUS66 KPDT 152132 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 232 PM PDT Wed May 15 2019 .SHORT TERM...Tonight through Friday Night...A trough currently centered off the coast will send several bands of precipitation through the area for the next 24 to 48 hours. The entire area will have a chance of rain tonight before tapering off from south to north overnight. One to two tenths of an inch of rain will be possible over most of the area. Tomorrow the trough will move to the coast with the central low coming ashore near the California/Oregon border in the afternoon. The low will open up into a wave Thursday night as the trough crosses the area. Moisture appears to be significant with the trough and rain will be heavy at times Thursday afternoon and evening. Rain amounts of a quarter to a half inch will be common in the lower elevations and up to an inch in the mountains. Central Oregon will get less, generally one to two tenths of an inch. The trough will be moving into Idaho Friday and while the area will continue to get a chance of rain Friday, Friday night will see the western portion of the area dry out while the eastern Columbia Basin and eastern mountains continue to have a chance of rain showers. Friday will bring up to a tenth of an inch of rain in the western portion of the area while the eastern Columbia Basin will get up to a quarter of an inch and the mountains up to a half inch. Friday night rain amounts will be just a few hundredths of an inch. With all the rain in the next couple of days, stream and rivers will be rising and will need to be monitored for possible flooding concerns in a few places. Today's cooler temperatures will continue with highs in the upper 50s and 60s tomorrow and in the mid 50s to mid 60s Friday. Perry .LONG TERM...Saturday through Wednesday...Upper level trough will approach the region late Saturday. Most of the day Saturday will be dry but rain will develop from southwest to northeast toward evening. A good dose of showers will continue into Sunday especially over Oregon as the trough drops south of the area. There could be a brief break in the inclement weather on Monday as indicated by the deterministic models but it will be short lived as another upper low consolidates and drops southward along the Pacific Northwest coast. This feature will likely produce at least scattered showers for Monday and Tuesday. Thunderstorm threat does not appear large through the period and have opted to keep them out of the forecast for now. After collaboration with neighboring forecast offices decided to leave TSTMS out of the forecast for next Wednesday...which as of now is showing the greatest thunderstorm potential. There will be plenty of forecast cycles that can be evaluated before then and thunder can be added as necessary. Rivers and streams will likely continue to run high with the expected rainfall in the short term but also with the continued rain this weekend into the middle of next week. 78 && .AVIATION...Previous discussion...18Z TAFS...Mostly VFR conditions are expected through the period. Areas of rain will spread northward today and this evening from central into northern oregon and southern Washington. Some MVFR CIGS are possible especially at KDLS...KRDM...and KBDN. Otherwise CIGS will generally be 4-6 thousand feet AGL with mid cloud above. Winds will be gusty from the s-sw this afternoon at KBDN and KRDM at 10-20 kt with a few higher gusts. Otherwise winds will be mostly 10 kt or less. 78 && .PRELIMINARY POINT TEMPS/POPS... PDT 51 63 49 60 / 70 90 80 70 ALW 52 67 50 62 / 60 90 80 80 PSC 56 70 55 67 / 70 70 80 60 YKM 51 65 50 65 / 80 70 70 60 HRI 52 66 50 66 / 70 70 70 60 ELN 48 63 50 57 / 80 80 80 70 RDM 42 62 38 59 / 50 50 60 30 LGD 46 60 44 54 / 60 100 90 70 GCD 45 57 42 55 / 70 90 70 70 DLS 52 66 50 64 / 80 60 60 60 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 83/78/78