textproduct: Pendleton

KEY MESSAGES

- Breezy winds developing in the Simcoe Highlands, Columbia River Gorge and Kittitas Valley Today, with winds peaking Friday.

- Cooling trend through Saturday with weekend Cascades rain. - More widespread rain showers Monday int Tuesday.

DISCUSSION

The synoptic setup features and eastward moving/exiting shortwave in advance of eastern pacific upper low that will dive southeast toward the BC/WA coast through Friday night. In the meantime for Thursday, a broad upper weakly diffluent flow will be in place with dry weather across the Columbia Basin and Mountain zones.

Breezy winds through the mountain gaps can be expected to increase over the next couple of days as the aforementioned upper low spreads to the PAC NW coast by Friday evening, bringing a marine push and frontal passage into the interior for Saturday. The Breezy winds today will be largely relegated tot he Kittitas valley and the eastern Columbia River Gorge/Lower Columbia Basin. Those conditions become more windy by Friday afternoon with sustained speeds though the Gorge on the order of 20- to 25 mph and higher gusts in the 30 to 40 mph range across the Simcoe Highlands and Columbia Basin of Oregon.

A secondary upper cold core low is shown by the EC/Canadian and GFS models to impact the region Monday night into Wednesday bringing opportunity for cloudy, cooler as well as more wet weather even for the Basin area and eastern Mountains. Russell/71

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Primarily westerly winds across the area Today with eh strongest winds through the Gaps. DLS will have the most robust wind speeds up to 15-20 knots and gusts up to around 20-35 knots in the afternoon. Much lighter winds elsewhere with VFR flight conditions anticipated across all terminals. Russell/71

FIRE WEATHER

Thursday and Friday pose elevated fire weather risk in the Columbia Basin as winds pick up leading to combined probabilities for low RH and strong winds. Combines probs of of 25% and 15 mph are between 30 and 70% across the Oregon Basin zones Today and the Washington Columbia Basin area on Friday. Chances for wetting rains increase to a 20-80% range by Saturday Night across the Cascades eastern slopes to the crest. As the upper low makes it way across the region over the weekend, a dry period on Sunday is anticipated. Another Upper low in the models digs farther south across the Interior Monday night spreading high wetting rain chances across the Cascades Crest (80%) and Eastern Slopes (30-65%). The eastern mountains will have similar chances for wetting rains but with a slight time lag into the Tuesday night time window on a 24 hour basis. Russell/71

Preliminary Point Temps/PoPs

PDT 75 47 72 45 / 0 0 0 0 ALW 76 52 74 50 / 0 0 0 0 PSC 80 50 77 47 / 0 0 0 0 YKM 80 47 74 43 / 0 0 0 0 HRI 78 50 74 45 / 0 0 0 0 ELN 71 44 66 38 / 0 0 0 0 RDM 76 39 73 36 / 0 0 0 0 LGD 74 43 75 43 / 0 0 0 0 GCD 77 42 80 40 / 0 0 0 0 DLS 77 52 71 48 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

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