textproduct: Pendleton

KEY MESSAGES

- Very windy on Saturday, with critical fire weather conditions.

- Diurnal breezes continue Sunday.

- Dry and warm through next week.

DISCUSSION

Southwesterly flow continues today around the periphery of a large high near the four corners, and low pressure off the British Columbia coast.

The pressure gradient will begin to tonight tonight and continue to do so into Saturday as the flow becomes more westerly as the low off the coast moves inland and its associated trough, moves through the Pacific Northwest. The trough will also bring a dry cold front with it. No precipitation is expected, but Saturday is expected to be breezy to windy with wind gusts 35 to 40 mph, and possibly higher in some areas. NBM probabilities of wind gusts >=39 mph are generally 80 percent or higher across the Kittitas Valley, Simcoe Highlands, Columbia Basin, Gorge and Foothills of the Blue Mountains. However, NBM probabilities of wind gusts >= 47 mph decrease and while they are locally greater than 70 percent in a few spots, like the Kittitas Valley, the broader area is generally 40 percent or less. A wind advisory is in effect for the Kittitas Valley, and will need to be monitored for these other locations.

Diurnal breeziness will continue into Sunday with the passage of a second trough (also dry), but gusts will be lower. NBM probabilities of wind gusts >= 25 mph is 80 percent or greater across the Kittitas Valley, Yakima Valley, Simcoe Highlands, Columbia Basin, Gorge, Blue Mountain Foothills and Central Oregon. However, probabilities of wind gusts >= 39 mph is fairly low, generally 20 percent or less, except for a few isolated locations.

For most of next week, the region is in a dry west to northwest flow, with warming temperatures.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

VFR conditions are expected at all TAF sites except BDN and RDM, where smoke from wildfires could bring MVFR conditions. Other sites could have MVFR as well, but probabilities are too low to include at this time.

DLS will see winds increase toward late after noon and gust around 25 kts. All other sites will have winds generally 10 kts or less.

FIRE WEATHER

There will be some diurnal breeziness today with very low RH. On Saturday, there will be a trough and dry cold front passage that will bring very breezy to windy conditions, especially to the Kittitas Valley, Columbia Basin, Gorge. However, RH values will be a bit higher, generally in the 20s and lower 30s in most areas. Fire Weather Watches remain in effect for Saturday for winds and humidities. Sunday will still be breezy as a second trough passes and humidity begins to decrease again. The rest of the week will see warming temperatures and decreasing humidity but lighter winds.

Preliminary Point Temps/PoPs

PDT 93 62 84 48 / 0 0 0 0 ALW 96 67 87 53 / 0 0 0 0 PSC 96 64 91 52 / 0 0 0 0 YKM 96 63 87 52 / 0 0 0 0 HRI 95 65 86 53 / 0 0 0 0 ELN 93 61 79 50 / 0 0 0 0 RDM 95 53 84 42 / 0 0 0 0 LGD 99 61 88 50 / 0 0 0 0 GCD 101 58 92 50 / 0 0 0 0 DLS 97 65 81 57 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...Fire Weather Watch from Saturday morning through Saturday evening for WAZ691>693. Wind Advisory from 11 AM to 11 PM PDT Saturday for WAZ026. OR...Air Quality Alert until noon PDT today for ORZ041-049-050-502- 503-505-506-509>511. Fire Weather Watch from Saturday morning through Saturday evening for ORZ691>700.