textproduct: Pendleton

KEY MESSAGES

1. Breezy to windy conditions and low RHs Today and Saturday *Red Flag Warning*

2. Dry, warm and breezy conditions will persist through the weekend and beginning of the week

3. Pattern shift mid-week could bring precipitation

DISCUSSION

Current satellite shows smokey skies over the region this afternoon which will continue through the forecast period. AQAs have been extended through Monday for all counties except Sherman, Gilliam and Morrow with Deschutes. Otherwise,increased southwest to westerly flow will keep the smoke moving east with a bit of reprieve from surface smoke.

Not much change to the short term forecast. Models currently show the surface thermal trough exiting the eastern portion of the region leaving mostly westerly flow at the surface. Even with the west flow, hot, dry and breezy conditions are still expected. Temperatures are in the mid to upper 90s across a vast majority of the region with humidity as low a single digits and winds between 10 to 20 mph with areas gusting between 20 to 40 mph (70-90% confidence). Red Flag Warning today through 11 PM for the Lower Columbia Basin of OR & WA, Eastern Columbia River Gorge, Warm Springs Reservation and Kittitas Valley.

Winds are expected to remain 10 to 15 mph and gusting between 25 to 35 mph through at least Tuesday with 70-80% of the NBM raw ensembles in agreement. Minimum relative humidity will slowly increase and the area will remain in elevated fire weather concerns but under critical thresholds. Westerly flow will continue through the weekend and beginning of next week with temperatures becoming slightly cooler. In house calculations shows much of the region to still be above seasonal average at 10-20 for today steadily decreasing to near 5 degrees above normal by Monday.

Models are coming into slight agreement with a pattern change by mid- week. Models are showing an upper level trough making its way into the region with a Four Corners High set up to the south. This has the potential to bring in some monsoonal moisture as well as some instability. Depending the track of the upper level low will determine just how much the area will see.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Mostly VFR conditions to prevail through the period. Settling smoke aloft has reduced vsby at site PSC late this evening. For now, have left a tempo group with MVFR vsby at site PSC through 10Z, with expectation that vsby improves after 10Z. Winds will generally be light through the period. Exceptions will be site DLS where breezy winds will continue late this evening, then redevelop late tomorrow morning; breezy winds will develop at site RDM mid afternoon tomorrow. Lawhorn/82

FIRE WEATHER

Red Flag Warnings in effect through 11 PM for winds and low relative humidities. This is for the Columbia River Basin of OR & WA, Eastern Columbia River Gorge, Warm Springs Reservation and Kittitas Valley for winds 10-20 mph gusting to 20-40 mph with humidity as low as 10-15%. Upper level flow aloft is from the west driving breezy westerly flow at the surface.

Breezy conditions are expected to persist through the beginning of the week with west winds 10-15 mph and gusting to near 20-30 mph (70- 80% confidence). Cooler more moist air will make its way across the Cascades Sunday. Humidity will see a slight increase by Sunday and will decrease fire weather concerns from critical to elevated.

Preliminary Point Temps/PoPs

PDT 56 89 54 88 / 0 0 0 0 ALW 62 91 61 89 / 0 0 0 0 PSC 58 92 57 92 / 0 0 0 0 YKM 59 93 59 92 / 0 0 0 0 HRI 61 91 59 91 / 0 0 0 0 ELN 59 88 56 86 / 0 0 0 0 RDM 47 90 46 89 / 0 0 0 0 LGD 55 92 53 90 / 0 0 0 0 GCD 53 93 53 91 / 0 0 0 0 DLS 61 90 60 89 / 0 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES

WA...Air Quality Alert until 5 AM PDT Tuesday for WAZ024-026>030- 521>523. OR...Air Quality Alert until noon PDT Monday for ORZ041-044-049-050- 502-503-505>511.