textproduct: Pendleton

KEY MESSAGES

- Patchy freezing fog to develop overnight into the early morning hours. Not expecting anything widespread.

- Dry, cool weather expected to last through early Friday thanks to a transient ridge.

- A couple weather systems to move in the area through early next week. Wetter pattern seems more favorable early next week.

DISCUSSION

Satellite this afternoon shows a small stratus deck near Central Oregon and close to Walla Walla that has since been dissipating through the afternoon hours. Areas of dense fog, if any, will continue lift out of the area as daytime mixing continues to wash out the remaining low stratus/dense fog.

Dry conditions are forecasted to continue going through Thursday/early Friday morning as ridging prevails over the area, bringing chances of dense fog/freezing fog re-develop overnight tonight and Thursday night. Not expecting wide aerial coverage of fog development, but lower elevations (especially sheltered areas) will see fog development in the early morning hours. Otherwise, winds through Friday are expected to remain light with lows in the upper 20s and low 30s.

There's good agreement that our next big shot of active weather will start on Friday as a trough digs down from the Gulf of Alaska down to just off the shore of California. Model trends have continued to trend snow amounts down from Friday through Sunday as the first system drives down too far south to bring any substantial moisture transportation into our area. Forecast ensembles are agreeing more that the precipitation over the weekend will remain light with NBM trends continuing to go down. NBM currently shows 2 to 5 inches for Snoqualmie (down from 5 to 8 inches from last night), with most of the Blues, Wallowas, and Oregon Cascades getting up to 5 inches of accumulated snow through Sunday (40 to 60 percent chance). It should be noted that 32% of clusters want to bring more moderate to heavy snow in the southern Oregon Cascades, which would lead to a heavier snow pack in one part of the Oregon Cascades.

Things become a bit more dicey as we head into Sunday through mid-next week. Overall, general ensembles have a good grip that that the system will move further south, leaving impacts minimal for our area. Generally consensus is that a second low/wave will dive down from the Gulf of Alaska sometime Monday and bring light to moderate mountain snowfall in the area, but the overall projected path of this next system remains unclear. Euro deterministic likes to bring the second wave down the coast of British Columbia down into the PacNW coastline. This solution will bring wetter weather with a greater chance of heavier snowfall. Meanwhile, GFS ensembles brings a more dry solution, trying to bring the second low pressure system far more off shore, minimizing the impacts compared to the Euro. Overall, an active pattern of light to moderate precipitation across the region is expected through mid-next week, but the overall intensity of the system remains to be seen as we get closer to the event.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

VFR conditions are mainly expected across the region tonight. However, DLS could see LIFR in low clouds/fog in the morning again. Additionally, there is a chance (<50 percent) of low clouds at BDN amd RDM, so have indicated SCT for now, but the possibility is there could be IFR. Winds will be light.

Preliminary Point Temps/PoPs

PDT 29 49 31 49 / 0 0 0 0 ALW 32 49 35 49 / 0 0 0 0 PSC 30 51 30 49 / 0 0 0 0 YKM 30 47 29 47 / 0 0 0 0 HRI 29 49 31 51 / 0 0 0 0 ELN 28 45 30 44 / 0 0 0 10 RDM 24 51 23 50 / 0 0 0 0 LGD 28 51 28 49 / 0 0 0 0 GCD 28 51 28 50 / 0 0 0 0 DLS 32 51 36 49 / 0 0 0 10

PDT WATCHES/WARNINGS/ADVISORIES

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