2017 CWICC Support Daily Air Quality Long Report 9/18/2017 Okanogan-Wenatchee National Forest Prepared By: Lou Ballard ARA

Fire Summary: The Jolly Mountain fire is currently burning in the Yakima River basin on the Okanogan- Wenatchee National Forest, north of Cle Elum, WA. The current fire size is 36,808 acres an increase of 0 acres Minimal fire behavior. The Uno Peak fire is currently burning north of Lake Chelan with a current size of 8,726 acres an increase of 0 acres. Minimal fire behavior with isolated torching, flanking and backing. The Norse Peak fire is burning northwest of Yakima. The current size is 52,502 acres an increase of 0 acres. Moderate fire behavior with backing, creeping and smoldering. Diamond Creek fire is 129,000 an increase of 1,700 acres. Moderate fire behavior with single tree torching, flanking and backing.

Air Quality looking north from Jolly Mountain ICP (19 Sept 2017)

WEATHER DISCUSSION for Diamond Creek: A large pacific upper trough will continue cool and showery conditions over the Diamond Creek fire today. Tonight conditions will begin to stabilize with the setting of the sun, allowing for decreasing cloud cover. Wednesday will continue to be unsettled, but potential for precipitation taper off some as the trough digs to the south.

WEATHER FORECAST FOR Tuesday (DAY-SHIFT): WEATHER: Increasing clouds (80% coverage). A 20% chance of rain and snow showers in the morning, an 80% chance of rain and snow showers in the afternoon. A slight chance of a thunderstorm in the afternoon.

TEMPERATURES: 5500-6500ft: 42-48°, 6500-7500ft: 36-42°. HUMIDITY: Minimum 60-65% bottom, 67-72% top. 20 FT WINDS: RIDGETOP – West 10-15 mph. Gusts to 20 mph during the afternoon. SLOPE/VALLEY – West 5-10 mph. Gusts to 15 mph in the afternoon. HAINES INDEX: 3 very low. LAL: 1 until 1200, then 2. CWR: 40% SNOW LEVEL: 5000 feet.

Tonight: Decreasing clouds. A 30% chance of rain and snow showers during the evening. Min temps 27-32° midslope to ridgetop, 34-39° lower slopes. Max RH 85-95%. Valley winds becoming downslope/downvalley 2-5 mph around 1800. Ridgetop winds northwest 10-15 mph. Snow level hanging around 5000 feet.

OUTLOOK FOR Wednesday: Mostly cloudy (70%). Areas of smoke. A 40% chance of rain and snow showers. Highs 40-46° bottom, and 34-40° top. Min RH 63-68% bottom and 70- 75% top. Ridgetop winds: northwest 10-15 mph with gusts approaching 18 mph. Slope valley winds: northwest 8-12 by midday with gusts approaching 15 mph during the afternoon. Haines Index: 3 very low. LAL: 1. CWR: 20% SNOW LEVEL: 5000 feet.

EXTENDED FORECAST (Thursday through Saturday): Cool and unsettled fall-like weather will continue into Thursday. Friday shower activity will be on the decrease, as upper ridging begins building back in, resulting in a warming trend for the weekend.

Below is the Smoke Forecast Outlook issued for 9/19/2017).

This forecast was based on current and predicted weather, visual observations, Blue Sky Modelling, and persistence forecasting. There are smoke monitors set up in Cle Elum, Yakima, Ellensburg, Leavenworth, Wenatchee, Chelan, Winthrop, Twisp, Tonasket, Omak and Okanogan, WA that were used as input into this forecast.

Blue Sky Run, Daily Average PM 2.5, valid to 1759z 9/19/2017. Shows decreasing smoke in communities

According to the Hysplit model (9/19/17 1700). Smoke from the Jolly Mountain Fire will transport northeast into Northeast Washington. Smoke from Jolly Mountain will possibly impact Wenatchee.

According to the Hysplit model (9/19/17 at 1700). Low level smoke from the Uno Peak Fire will move east into the Columbia Basin. Uno Peak is not producing large amounts of smoke so will only contribute slightly to overall smoke in the area.

According to the Hysplit model (9/19/17 at 1700). Smoke from the Norse Peak Fire will transport east. Low level smoke may impact Ellensburg.

According to the Hysplit model (9/19/17 at 1700). Smoke from the Diamond Peak Fire will transport into Canada but may settle back into the Okanogan Valley.

Using the above mentioned products, along with persistence forecasting, we determined that there will be moderate impact to the communities of note. The smoke column from the fire along with regional haze from other fires in the area will be visible.

Contacts of Note: Brian Watts, PSC Diamond Creek