textproduct: Pendleton

DISCUSSION

The key aspect going forward though this weekend is snow in the mountains and windy conditions for the Blues and Grand Ronde valley. Highway 11 between Walla Walla and and PDT windy NBM 5.0/NBMEXP capturing much stronger winds along the foothills of the northern Blues, commonly between 40 and 50 kt gusts peaking at around 21z (1 PM Sunday). The Central Oregon zone including Bend, Redmond, U.S. hwy 97, might see some gusty winds to 40 mph as well on Sunday based on these NBM wind forecasts. The latest NBM has backed off on the more widespread high end wind values above 50 knots, relegating this high values to smaller areas, but still in lower elevation where travel impacts can be realized. The high wind watch will be converted to a High Wind Warning. Additionally the Winter Weather advisories remain in effect though this evening for the highest elevations of the WA Cascades. The observation at MT Bachelor show snow has ended, and the Oregon Cascades Advisory will be ended canceled early along with the expiration of headlines for North Central Oregon late afternoon. HREF trends suggest an early end to the snow across the WA Cascades/Simcoe highlands area before 7 pm. Snow redevelopments overnight in the WA Cascades will continue through the day on Sunday, however the NBM mean probability for accums exceeding 6 inches area very low (less than 10%) and only significant (above 50%) in the higher elevations of the Upper slopes.

A continued relatively active weather pattern is in store for beyond the weekend as 988 mb surface low off the OR/ WA coast lifts north to off the BC coast Sunday night. The system will drag an attendant occluded/cold frontal boundary moves into the PAC NW Monday Night, spreading rains and possibly some locally mixed phase precipitation near the Cascades foothills, however largely snow in the elevated areas especially above 5,000 ft as snow levels fall to the 3500 ft levels through the WA Cascades and the Kittitas and Yakima areas. A typical wet pattern lingers until the associated mid level trough passes into the Inland NW early Wednesday and drier, slightly more subsident west northwesterly flow aloft develops. Russell/71

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

All TAF sites are currently VFR and will remain as such through much of the forecast period. YKM has a 30% probability of seeing light snow again between 16-19 with VIS dropping to 5SM and CIGs to 2500 feet. DLS will also see a decrease in VIS as showers will make their way after 19Z bringing VIS as low as 4SM and CIGs to as low as 1500 feet (50-70%). Otherwise, all remaining TAF sites will be VFR with winds below 12kts. However, BDN/RDM will see an increase in winds 12-14 kts with gusts to 21-23 kts between 15-17Z. 90

Preliminary Point Temps/PoPs

PDT 33 56 39 58 / 10 20 50 50 ALW 36 55 40 57 / 10 30 60 60 PSC 29 52 37 56 / 10 30 60 50 YKM 28 46 34 47 / 20 60 80 80 HRI 30 55 37 57 / 10 30 60 50 ELN 26 41 31 43 / 30 70 80 90 RDM 30 52 36 54 / 10 30 50 40 LGD 32 48 36 51 / 10 20 30 40 GCD 30 50 37 52 / 0 10 20 30 DLS 32 48 38 49 / 30 80 90 90

PDT WATCHES/WARNINGS/ADVISORIES

WA...Winter Weather Advisory until 10 PM PST this evening for WAZ521>523. OR...Wind Advisory until 10 PM PST this evening for ORZ049. High Wind Warning until 10 PM PST Sunday for ORZ049-507.