Updated 10am MDT Wednesday, August 3, 2016
Valid through Noon MDT Thursday, August 4, 2016
Air quality is forecast to remain in the Good to Moderate air quality category across the state today. Impacts are less substantial today with Pocatello, Franklin, Idaho Falls, and Salmon the only locations in south Idaho with currently- elevated monitors reading in the Moderate Category. In north Idaho, monitor readings are currently in the Moderate category in the Moscow area. Expect higher readings in the evening and early morning before improving during the day.
An upper level low pressure system will track east into Montana along the Canadian border this afternoon and will still provide for a chance of showers across the extreme northern Panhandle. Expect winds from the west-northwest with southwest winds within the Purcell trench and the Upper Snake River Plain. Surface wind speeds will range from 5-10 mph across north Idaho and 10-20 mph across south Idaho. Mixing heights will range from 2,000-6,000 feet AGL in the afternoon with transport winds from the northwest-west at 10-15 mph. Again, the Purcell Trench and Upper Snake River Plain will see southwest transport winds at 10-15 mph and 10-20 mph, respectively. On Thursday, a ridge of high pressure will briefly establish over northern Idaho. Wind speeds will be light, in the 2-8 mph range, with variable direction across the state. Wind directions at higher speeds will be primarily from the east across southern Idaho and northwest-west across northern Idaho. Mixing heights will range from 2,000-10,000 feet AGL in the afternoon tomorrow.
Smoke impacts today are expected to be minimal today with the cooler temperatures and lighter wind speeds. Brief periods of heavy, localized smoke should be expected in the morning before the inversion lifts around 11am-12noon today. The regions that may see smoke this evening will extend through the Snake River Plain into the Island Park area before turning down-valley Thursday afternoon. High-altitude smoke is expected to track west into the Treasure Valley tomorrow afternoon. Due to lighter wind speeds, transport of smoke is expected to be limited to areas near fires.
DEQ Air Quality Advisories:
· The Twin Falls Regional Office has issued a Stage 1 Forecast and Caution for Blaine County. Valid through 1pm August 3rd.
· The Idaho Falls Regional Office has issued a Stage 1 Forecast and Caution for Butte, Custer and Lemhi Counties. Valid through 9 am August 3rd.
· The Lewiston Regional Office has issued a Stage 1 Forecast and Caution for Clearwater, Idaho, Latah, Lewis, and Nez Perce Counties (off the Nez Perce Reservation). Valid through 10 am August 3rd.
The USFS installed monitors near Stanley, Idaho and Lowman, Idaho. The information can be found at http://www.wrcc.dri.edu/cgi-bin/smoke.pl
• Stanley, ID monitor is Smoke #217
• Lowman, ID monitor is Smoke #66
• Users should be aware that the Forest Service site reports the data in Coordinated Universal Time (UTC). To convert from UTC to Mountain Daylight Time, subtract 6 hours.
View DEQ near-real time monitoring at: http://airquality.deq.idaho.gov/
Smoke forecasts are dependent on predicted fire growth and weather. If conditions change unexpectedly, impacts could occur. When visibility starts to go below 5 miles, sensitive groups should minimize outdoor activities. Everyone else should minimize prolonged or physical activity outdoors. Visit the Idaho Smoke Blog for more information at http://idsmoke.blogspot.com/
Your eyes are your best tools to determine if it’s safe to be outside. Even if you smell smoke, the air quality may still be good.
Unhealthy for Sensitive Groups
Less than 1
How to estimate air quality based on visibility for areas without an air quality monitor or airport visibility estimate:
a. Face away from the sun.
b. Determine the limit of your visible range by looking for targets at known distances (miles).
c. Visible range is when an object you can easily see in the distance disappears.
d. Use the visibility values above to determine the local wildfire smoke category.