textproduct: Pendleton

KEY MESSAGES

- Elevated to locally critical fire weather conditions continue through the week with overlapping breezy winds and dry air in the region.

- Widespread smoke and haze prevail form local and regional wildfires in the area, giving off sub-par air quality.

- HeatRisk increases through the mid-week as a warming trend continues through Thursday.

DISCUSSION

Satellite and night physics continue to advertise widespread smoke and haze across the region from regional and local wildland fires. An upper-level ridge will continue to contribute poor mixing in the atmosphere over the next few days, allowing sub- par air quality across the forecast area. The upper level ridge will continue to amplify over the next couple of days, allowing smoke transport to persist in the area and settle through at least the middle to late week (>90% confidence). As such, local agencies from Washington and Oregon have maintained Air Quality Alerts/Advisories highlights until further notice.

The upper level ridge will continue to move east with the axis over the area pushing overhead in the Thursday/Friday time frame. An expected warming trend (>90% confidence) will continue through the week, with high temperatures peaking Thursday with parts of the Columbia Basin reaching triple digit heat (70-80% confidence). Outlooks have placed widespread >90% chances of 'Moderate' HeatRisk developing. With that in mind, smoke can effect the high temperature with places inhibiting heavier/thicker smoke plumes will see "cooler" than expected temperatures.

Guidance in the synoptic level through Friday is in good agreement that the pattern will turn into a zonal/quasi-zonal flow with tighter pressure gradients, resulting in breezy to locally windy conditions developing late this week. With dry air lingering with minimum relative humidities still in the 10-18 percent range Friday, chances of critical weather conditions developing go up with 50-70% confidence.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Borderline VFR and MVFR conditions continue through the night with widespread smoke and haze impacting the region. Local and region wildland fires are contributing to poor air quality and reduced visibility conditions. Smoke concentrations will lessen during peak heating hours with additional mixing improving conditions somewhat through the day. Otherwise, winds remain fairly light with mostly less than 12 mph sustained winds.

Preliminary Point Temps/PoPs

PDT 88 52 94 58 / 0 0 0 0 ALW 90 58 96 64 / 0 0 0 0 PSC 91 56 96 60 / 0 0 0 0 YKM 90 59 95 62 / 0 0 0 0 HRI 90 58 96 61 / 0 0 0 0 ELN 88 59 94 62 / 0 0 0 0 RDM 89 48 97 53 / 0 0 0 0 LGD 89 52 97 56 / 0 0 0 0 GCD 90 53 98 57 / 0 0 0 0 DLS 92 63 98 65 / 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 5 AM PDT Tuesday for ORZ041-044-049- 050-502-503-505>507-509>511.