WILDFIRE SMOKE
FORECAST
OREGON DEPARTMENT
OF FORESTRY WEATHER OFFICE
330 PM PDT MON JUN
9, 2014
SIGNIFICANT FIRE INFORMATION:
Two Bulls Fire –
10 miles NW of Bend,
OR.
For updated
“Significant Fire” details, visit ODF’s fire blog at http://wildfireoregondeptofforestry.blogspot.com/
or the Northwest Interagency Coordination Center (NWCC) at http://www.nwccweb.us/index.aspx.
A “Significant
Fire Potential” map, for ODF protected lands, is available at (http://nfdrs.smkmgt.com/ODF_Significant_Fire_Potential.png).
AIR QUALITY:
DEQ nephelometer readings
returned to near “baseline” levels this afternoon across central Oregon (i.e.
Sisters, Bend, Crater Lake) but remain slightly elevated from south-central
Oregon across SE Oregon (i.e. Klamath Falls to Burns). Although satellite imagery shows considerably
less smoke being produced by the “Two Bulls Fire’ compared to 24 hours ago,
there is still some residual smoke along, south, and east of a (Southern
Cascades)-(Bend)-(John Day)-(Baker City) line.
Statewide air
quality index readings are available at http://www.deq.state.or.us/aqi/index.aspx
SMOKE DISPERSION FORECAST:
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.
TODAY:
A stable NW flow aloft is continuing to bring dry weather
to the state, with the exception of some morning drizzle along the extreme north
coast. An upper-level disturbance cut
across Washington today; increasing the onshore flow across Oregon. Transport winds are generally NW-N at 10-20
mph across central Oregon this afternoon; backing to W-NW across eastern
Oregon. So long as the increasing winds
do not activate the “Two Bulls Fire,” air quality should continue to improve for
areas south and east of the fire. If the
fire behavior suddenly increases, then areas east-south of the fire will be in
the potential path for additional wildfire smoke. Some settling of smoke near the ground is
likely tonight, as the air mass stabilizes and winds slacken.
Tuesday:
A dry and stable NW flow aloft should to continue to
produce locally brisk afternoon NW transport winds with local drainage flows
becoming more dominant Tuesday night.
This will lead possible wildfire smoke impacts east-south of the “Two
Pulls Fire,” if it is still active.
Wednesday:
The flow aloft weakens as a flat and transitory
upper-level ridge moves over Oregon.
That will act to decrease the onshore flow and slacken winds across
central and eastern Oregon. If the “Two
Pulls Fire” is still active, smoke impacts will be possible NE-SE of the
fire.
EXTENDED
OUTLOOK:
A stronger weather system is forecast to come onshore
Thursday and Friday, bringing cooler temperatures, increasing W-NW winds, and a
threat of showers to mainly the northern half of Oregon.
Current Weather
Forecasts from the Portland, Medford, Pendleton, and Boise National Weather
Service offices are available at: http://www.wrh.noaa.gov/pqr/, http://www.wrh.noaa.gov/mfr/, http://www.wrh.noaa.gov/pdt/, and http://www.wrh.noaa.gov/boi/
respectively.
Current Western
Region Fire Weather Forecasts are available via: http://www.wrh.noaa.gov/firewx/main.php.
This bulletin is
also available at:
ODF Smoke Management Meteorologist