textproduct: Pendleton

KEY MESSAGES

- Dry and warm with diurnal breezes through Wednesday.

- An upper level trough will then move in followed by a return to southwesterly flow. Then there will be opportunities for mountain showers and thunderstorms for the end of the week.

DISCUSSION

Dry westerly flow will continue over the Pacific Northwest for the next several days. Breezy diurnal winds are anticipated, with the Simcoe Highlands, Columbia Basin, Gorge and Kittitas Valley having afternoon wind gusts in the 20 to 30 mph range, possibly as high as 35 mph today and Tuesday, then decreasing a bit on Wednesday.

NBM probabilities of wind gusts >=25 mph are >80 percent in these areas today, and similar on Tuesday, though with slightly less areal coverage. NBM probabilities of wind gusts >=39 mph are 70-90 percent in the Kittitas Valley and generally less than 50 percent everywhere else.

High temperatures today will be similar to yesterday, perhaps a degree or two cooler in some locations. Tuesday will be about the same as today and Wednesday will be a couple of degrees cooler. With the slightly lower temperatures by midweek, RH values will increase a couple of percentage points today and a few more going into Wednesday. This will help with fire weather conditions, though they will still remain elevated.

By midweek, low pressure in British Columbia will move south and push a trough into the Pacific Northwest. This low could potentially trigger some light showers over the Washington Cascades Wednesday, but not much more than that.

By Thursday, southwest flow will develop behind the departing low and will strengthen into the weekend. There will also be increasing monsoonal moisture specially Friday onward.

While it is too early to tell exactly how things will develop this far out, there is definitely some potential (15-30%) for mainly mountain showers and thunderstorms over central and eastern Oregon.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

VFR conditions are generally expected through the TAF period. The only current exception is RDM where MVFR is occurring due to smoke. BDN now has some smoke that has moved in with IFR conditions. Not sure how long this will last. RDM may improve later this afternoon, as winds increases but confidence is marginal at best.

Winds have remained gusty at DLS to around 20 kts and are expected to increase this afternoon to around 30 kts. Winds are expected to gust at PDT, BDN, RDM and YKM to around 20 kts this afternoon, before all sites return to 10 kts or less this evening. ALW and PSC will remain 10 kts or less through the period.

Preliminary Point Temps/PoPs

PDT 88 53 88 57 / 0 0 0 0 ALW 89 60 89 62 / 0 0 0 0 PSC 92 57 91 58 / 0 0 0 0 YKM 92 58 92 59 / 0 0 0 0 HRI 91 58 90 59 / 0 0 0 0 ELN 85 56 86 56 / 0 0 0 0 RDM 89 47 89 47 / 0 0 0 0 LGD 90 53 90 53 / 0 0 0 0 GCD 91 53 92 53 / 0 0 0 0 DLS 89 61 89 62 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...Air Quality Alert until 5 AM PDT Tuesday for WAZ024-026>030- 521>523. OR...Air Quality Alert until noon PDT today for ORZ041-044-049-050- 502-503-505>511.