textproduct: Pendleton

KEY MESSAGES

- Above normal temperatures and dry conditions continue through next week

- Breezy to locally gusty gap winds Friday and Sunday

- Low RHs and breezy winds will overlap the remainder of this afternoon and tomorrow afternoon in the Cascade gaps and Lower Columbia Basin

DISCUSSION

Tonight through Sunday: Breezy Cascade gap winds continue this afternoon in the wake of a shortwave exit earlier this morning. Otherwise, high thin scattered decks of cirrus are also spreading across the region this afternoon.

Upper level ridging will move over the forecast area this afternoon and tonight, continuing a drying trend with winds becoming light overnight. Friday, a shortwave will briefly flatten the ridge as it slides into the PacNW. Very little moisture will accompany the shortwave passage tomorrow, resulting in dry conditions continuing. However, a dry frontal boundary will follow the shortwave, resulting in increasing winds through the Cascade gaps and into the lower elevations of the forecast area. Winds will generally be 15-25mph with gusts up to 40mph, however winds will be 25-35 mph with gusts 45-55 mph in the Kittitas valley tomorrow afternoon (confidence 75-85%).

Upper level ridging will rebound late Friday and prevail through Saturday night. While dry conditions will persist through the weekend, another shortwave will flatten the ridge for Sunday, resulting in another day of breezy to locally gusty winds in the afternoon and evening.

Monday through Wednesday: There is good agreement amongst ensemble cluster solutions that upper level ridging will once again build back over the region, resulting in dry and warm conditions with light winds Monday (confidence 60-75%). Tuesday and Wednesday, agreement lowers quite a bit as about 50% of members favor a trough passing over the PacNW while the other about 50% favor ridging persisting overhead. The troughing solution (favored by ECWMF members) would bring light showers to the Cascade crest late Tuesday and Wednesday with breezy conditions and temperatures in the mid 70s to lower 80s in the lower elevations; the ridging solution (favored by GFS members) would continue a drying trend with temperatures warming into the upper 80s to lower 90s in the lower elevations. Lawhorn/82

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

VFR conditions to prevail through the period. Breezy winds 12-17kts with gusts to 25kts will continue at sites DLS/PDT into the late afternoon and early evening, while winds will increase around 21Z at sites RDM/BDN and persist into the evening. Breezy winds will remain at site DLS overnight, with light winds prevailing elsewhere overnight. Winds will become breezy at all sites tomorrow, with strongest winds at sites DLS/PDT. Lawhorn/82

FIRE WEATHER

Afternoon relative humidities will remain low through next, with areas of central Oregon reaching single digits by Saturday. Gap and Basin winds will continue to be locally breezy through this afternoon, and will increase tomorrow as a dry front moves across with breezy to locally gusty westerly winds developing in the Basin and adjacent valleys and foothills. Poor to moderate recovery tonight, with moderate to good recovery through the weekend.

HYDROLOGY

The Naches River near Naches is forecast to remain above action stage for the next week. Above-normal temperatures are forecast to continue, and significant precipitation is unlikely (90 percent confidence) for the next week.

Preliminary Point Temps/PoPs

PDT 49 75 47 77 / 0 0 0 0 ALW 52 75 50 77 / 0 0 0 0 PSC 54 82 49 81 / 0 0 0 0 YKM 50 79 45 81 / 0 0 0 0 HRI 52 77 48 80 / 0 0 0 0 ELN 46 70 42 77 / 0 0 0 0 RDM 41 76 38 84 / 0 0 0 0 LGD 42 73 41 77 / 0 0 0 0 GCD 43 76 41 80 / 0 0 0 0 DLS 49 75 48 83 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...Wind Advisory from 11 AM to 11 PM PDT Friday for WAZ026. OR...None.