textproduct: Pendleton

DISCUSSION

Satellite imagery reveals mostly clear skies across the forecast area as the region is under a dry northwesterly flow aloft on the east side of an upper-level ridge of high pressure.

Farther west, the next two weather systems that are expected to influence our weather are visible offshore in the Pacific. A weak shortwave trough will pass overhead tonight through Monday, though the system is only expected to bring mid- to high clouds with little to no precipitation.

Upper-level ridging will return Monday night through Tuesday morning. Tuesday afternoon and evening, a stronger shortwave is shown in ensemble and deterministic guidance. While precipitation chances are best for the mountains, the main concern will be some wintry mix for the lower elevations if the cold pool in the Columbia Basin continues to linger. Thermodynamic profiles from current guidance are supportive of snow for the Kittitas Valley and higher portions of the Yakima Valley, with pockets of light freezing rain for the Columbia Basin below 3000-3500 ft.

Thursday through Saturday, a warmer, wetter pattern is likely (60-70% chance) for the Pacific Northwest, but the best chances (60-80%) of precipitation will be along the Washington Cascades with lower chances (40% or less) elsewhere.

AVIATION...00Z TAFs

Clear and dry pattern continues to pave way for VFR conditions through the next 24-hours. Guidance no longer hints at ALW going back to IFR/LIFR conditions as it was showing during the 18Z TAFs. Over the next 24-hours a very brief stratus cloud could develop over DLS/ALW during the sunrise hours tomorrow, but nothing expected to be prolonged if anything develops (10 to 20 percent chance of occurring). Otherwise, conditions continue to favor higher CIGs and VIS with light and variable winds.

PRELIMINARY POINT TEMPS/POPS

PDT 20 38 24 38 / 0 0 0 0 ALW 23 37 26 38 / 0 0 0 0 PSC 22 35 22 38 / 0 0 0 0 YKM 22 34 23 37 / 0 0 0 0 HRI 22 36 23 37 / 0 0 0 0 ELN 20 32 22 33 / 0 0 0 0 RDM 22 48 25 47 / 0 0 0 0 LGD 23 39 25 42 / 0 0 0 0 GCD 24 45 25 46 / 0 0 0 0 DLS 25 39 28 40 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

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