Updated 1000 MDT Tuesday, July 15, 2014
Valid through Noon MDT Wednesday, July 16, 2014
The 2014 wildfire season is currently underway as southwest Idaho experienced 20 new fire starts due to lightning on Sunday with additional starts on Monday. The upper level low pressure system currently located over the borders of northwest Montana, Idaho, and Canadian British Columbia, responsible for thunderstorms over southern Idaho the past two days, is forecast to drop to the southeast along the lee-side of the Rockies. This will move the convective -and thereby lightning favored- regions to the Eastern Highlands and Wyoming/Idaho/Montana border this afternoon. Along this region, 50 mph wind gusts are possible near storms. With the movement of this upper level low pressure system, transport winds will shift to the northwest, providing slightly cooler maximum temperatures this afternoon. This will also cut off any influx of monsoon moisture from the Great Basin.
Across the Snake River Plain, winds will be from the northwest in the Lower Snake and from the west-northwest across the Middle and Upper Snake River Plain. Wind speeds will range from 8-18 mph with gusts from 23-25 mph in the Lower and Middle Snake. Dispersion is expected to be good as mixing heights range from 6,000-10,000 feet AGL. This will limit impacts to regions near fires and to the immediate southeast of fires. This dry northwest flow aloft will persist into Saturday.
Smoke impacts today are forecast to be light and will likely be in the Garden Valley and Idaho City areas with transport this afternoon across the Middle Snake River Plain to Twin Falls as the northwest winds will transport smoke from the Whiskey Complex and Blue Jay fire. Nocturnal drainage flows will transport this smoke south into the Upper Treasure Valley, impacting Boise, before moving southeast along the valley and into Mountain Home. Impacts from large wildfires in Oregon are not expected to impact Idaho today; however, impacts may be possible late Wednesday evening as transport winds shift from northwest to a more westerly flow.
Air quality monitors indicated Unhealthy in Idaho City and Moderate in Garden Valley this morning. Daytime heating and good mixing will allow for clearing in the afternoon.
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. Refer to the Smoke and Health Tab on the Idaho Smoke Information Blog for additional health information.
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