Current situation

Sunny and dry conditions again prevail across Oregon this week. Mild temperatures will give way to warmer conditions, melting snow and drying fuels faster. This will raise fire risk across the state. There have already been twice as many wildfires on ODF-protected land compared to the same time last year, with more than twice as many acres burned.

May is Wildfire Awareness Month, a time when homeowners are urged to take steps to reduce the risk of wildfire around their house and other structures. Among these are clearing debris from roofs and gutters, cutting back brush from around structures, and removing lower branches from trees.

Saturday, September 10, 2011

Smoke forecast for this weekend - ODF Weather Office


2:35 PM PDT FRI SEP 9 2011


Due to the various fire locations, a variety of wind patterns, and a stable atmosphere, wildfire smoke has been able to spread out over most of the state during the past few days. Virtually all of the state’s smoke monitoring equipment, operated by the DEQ and LRAPA, is showing elevated smoke levels. The highest readings this afternoon (Friday) were at locations near active fires in the northern Cascades and North-Central Oregon (Lyons, Government Camp, The Dalles), southwest Oregon (Shady Cove, Medford), and in northeastern Oregon (La Grande, Cove).

DEQ nephelometer readings (statewide) are available at:

LRAPA nephelometer readings (Lane County) are available at:


Wildfire smoke dispersion depends on the stability of the atmosphere as well as wind direction and speed. A stable atmosphere holds smoke to the ground and an unstable atmosphere allows smoke to rise and dissipate. Smoke is typically mixed to higher altitudes during the afternoon, when daytime heating destabilizes the air mass. Conversely, smoke tends to settle near the ground and in drainages during the overnight and early morning hours.

Saturday: As the upper-level ridge of high pressure continues to build over the region, transport winds are forecast to turn more easterly across the state. That should further increase smoke levels across much of western Oregon and all areas west of active fires in general. The air mass will continue to stabilize, so the “dry” thunderstorm threat will be minimal. Warm air aloft will only allow for marginal daytime mixing of the air mass. Western Oregon smoke levels will likely peak Saturday night into early Sunday.

Sunday: The surface thermal trough is forecast to shift from the coast to over the western valleys Sunday morning. Winds will slacken and turn weakly southerly across most of the state. Smoke levels should peak along the I5 corridor, with smoke levels increasing again for areas to the north of active wildfires. The thermal trough is forecast to shift into Central Oregon Sunday afternoon. That will initiate a westerly transport flow into western Oregon, and begin to improve air quality along the I5 corridor. In contrast, an increasing westerly flow will deteriorate air quality for areas to the east of active fires in Central Oregon. Winds in eastern Oregon will become light with warm air aloft allowing for only marginal vertical mixing of smoke. Smoke from active fires in eastern Oregon could fan out in any direction.

Monday: The surface thermal trough will begin the day over Central Oregon; progressing into eastern Oregon in the afternoon. Increasing onshore flow should dramatically improve air quality across the interior valleys of western Oregon (assuming, of course, that no new wildfires pop up in the coast range). In contrast, areas east of active fires, in Central Oregon, may see an increase in smoke. Light transport winds are forecast for the eastern third of the state, with a tendency for a northwesterly component late in the day. That would likely mean an increase in smoke for areas to the southeast of active wildfires in northeastern Oregon.

This information is provided by the Oregon Department of Forestry Weather Office at the request of the Oregon Department of Environmental Quality.It is also on the web at:

No updates before Monday, September 12th.
For more information, contact DEQ’s Larry Calkins: 541-467-8297 or

Pete Parsons
ODF Meteorologist

No comments:

Post a Comment

Have a question/comment about this season's wildfire activity on the 16 million acres of private and public forestlands that the Oregon Dept. of Forestry protects from wildfire? Let us know. Please keep your remarks civil and free of profanity.

Comments and questions

The purpose of this blog is to provide breaking news about wildfire activity on the forestlands protected by the Oregon Department of Forestry. We invite you to post questions or comments you have about current wildfires. Please keep your posts civil and free of profanity. You are also welcome to contact us by email at:

Current wildfire info

Cool, wet weather in the winter of 2016-17 ended Oregon's long drought and left a thick mountain snowpack. It didn't take long for that to melt and vegetation to dry out due to a series of heatwaves and a prolonged stretch of dry weather over the summer. As forest fuels dried, fires started and spread, many from lands adjacent to those protected by ODF, such as the Chetco Bar Fire in Curry County. That one fire accounted for 46% of the 47,537 acres of land protected by ODF which burned in 2017. Of fires originating on ODF-protected land, 95% were put out at less than 10 acres.

What we do

Protection jurisdiction
The Oregon Dept. of Forestry protects 16 million acres of private and public forestlands from wildfire. This includes all private forestlands in Oregon as well as state and local government-owned forests, along with 2.8 million acres of federal Bureau of Land Management lands in the western part of the state. In total there are about 30.4 million acres of forest in Oregon.

Fire suppression policy
The department fights fire aggressively, seeking to put out most fires at 10 acres or smaller. This approach minimizes damage to the timber resource and fish and wildlife habitat, and protects lives and property. It also saves money. While suppressing large fires can cost millions of dollars, economic and environmental damage from wildfires can be many times greater.


About Me

My photo
Oregon Dept. of Forestry's public information officers in Salem, Ore., maintain this blog. During the wildfire season, we spend much of our time reporting on fires and firefighting to news media and the public.