textproduct: Pendleton

KEY MESSAGES

- Near- to below-normal temperatures into next week.

- Precipitation this evening into Sunday morning, mainly for eastern Oregon and far southeast Washington.

- Low chance (30% or less, except for freeze-prone areas) of a season-ending freeze for the eastern Columbia River Gorge Monday.

DISCUSSION

Composite reflectivity showed a few showers popping off the NW Blue Mountains of Washington, near Walla Walla as well as elevated echoes over Franklin county early This Afternoon. Radar returns were still sparse over the Oregon Cascades where initial probabilities associated with the incoming synoptic system for Tonight were found. Elsewhere, dense fog resulted in limited visibility to a quarter mile or less during the morning to early afternoon hours across the upper end of the Kittitas valley, the Walla Walla Valley as well as the Foothills of the Northern Blue Mountains. Based on mesonet obsevations and roadcam networks, these areas have improved visibility to at least 2 miles or better. REFS trends for precipitation Tonight suggest around a tenth and up to a quarter of an inch of liquid equivalent precipitation across the central Oregon mountains/Oregon Cascades through about the middle of the overnight hours. And meanwhile these trends have tended to reduce QPF amounts in the last few days for the northern Blue Mountains, where the mean QPF across the Blue Mountains and Wallowas on average is up to a tenth of an inch (30 to 50% confidence) with REFS QPF max amount over the Eagle Caps upwards between a quarter and one half inch of liquid equivalent. Rain snow mix is possible higher than 6500 ft, however the REFS only offers about a half inch over the Oregon Cascade crest and one to two inches on the Eagle Caps. Sunday ultimately winds up being slightly warmer for parts of the forecast area like the Yakima Valley, and Lower Columbia Basin with abundant insolation and light westerly surface winds and highs in the upper 50s to low 60s in the Yakima and Columbia River Gorge.

The upper ridge develops Monday behind the exiting mid level trough, redistributing the light westerly wind field to light northeast across the Basin and potentially turning winds southerly and breezy in the Grande Ronde Valley by Overnight into Tuesday morning. Overnight low Temperatures through the eastern Columbia River Gorge still appear mild and above freezing over the next 7 day as to think at least at this time, low confidence exists in any anticipated freeze headlines for these last remaining last warning eligible zones, at least for the first week of November.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Visibility reduced in FG/BR and/or ceiling restrictions persist this morning into the early afternoon at ALW/DLS. Confidence is low with respect to when these restrictions will finally improve on the day but DLS LAMP guidance suggests cig improvement after 20z, and as for ALW visibility will have to be monitored for short term trends. Light winds at all terminals. Shower chances increasing (about 15 to 25 percent confidence) after 01 UTC at RDM BDN, and after 12z more probabilistic 20 to 35 percent rain chances for PDT to ALW.

Preliminary Point Temps/PoPs

PDT 34 53 31 57 / 20 20 0 0 ALW 38 52 34 56 / 30 30 0 0 PSC 33 59 31 56 / 10 10 0 0 YKM 32 60 30 55 / 0 0 0 0 HRI 32 57 31 56 / 10 10 0 0 ELN 27 56 26 52 / 0 0 0 0 RDM 25 51 22 56 / 20 0 0 0 LGD 36 52 29 56 / 30 40 0 0 GCD 35 49 30 58 / 20 20 0 0 DLS 36 61 34 58 / 10 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...None. OR...None.