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The Air Quality
Index at 9 a.m. on Wednesday, Aug. 22, 2018.
See the map above for current conditions.
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Forecaster: James Miller, USDA Forest Service
Air quality
across Oregon improved in the past 24 hours with the exception of Southern
Oregon where unhealthy conditions remain. On Wednesday morning, air quality at all
but one location in the Portland metro area was reporting unhealthy for
sensitive groups, a slight improvement over the widespread unhealthy air
quality indices on Tuesday morning. Moderate air quality indices were observed
throughout Northeastern Oregon Wednesday morning, whereas many locations
reported unhealthy conditions yesterday morning. A similar improvement was
observed in Bend and Eugene.
For the remainder
of Wednesday, the latest smoke models agree that conditions will continue to
improve in the Willamette Valley and along the coast. However, the westerly
winds aloft leading to improved air quality for Northwestern Oregon will push smoke
towards Central and Northeastern Oregon on Wednesday afternoon. Accordingly,
air quality across the Blue Mountains region, including the cities of La Grande
and Pendleton may deteriorate from moderate to unhealthy for sensitive groups
(or worse) on Wednesday before conditions improve begin to improve later in the
day Thursday. Confidence is high that air quality will return to the good
category for the major population centers throughout the Willamette Valley by
no later than Thursday morning, with earlier improvement possible in the
southern reaches of the valley (e.g. Corvallis, Eugene) where the marine air
push may bring cleaner, clearer conditions by Wednesday afternoon and evening.
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Near-surface smoke
forecast from the High-Resolution Rapid Refresh (HRRR) Model for Wednesday,
August 22, 2018 at 4 p.m.
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Near-surface smoke
forecast from the High-Resolution Rapid Refresh (HRRR) Model for Thursday,
Aug. 23, 2018 at 4 a.m.
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Unfortunately,
the latest runs of the High-Resolution
Rapid Refresh model suggest that smoke impacts will continue for many locations
in Central and Southern Oregon, including Ashland, Bend, Klamath Falls,
Lakeview and Medford for at least the next 36 hours.
For Thursday afternoon, the High-Resolution Rapid Refresh model runs
suggest a sharp transition between good and degraded air quality along a
southwest to northeast oriented line from roughly Port Orford on the coast to
near Boardman. Areas north and west of this boundary should expect good air
quality by tomorrow afternoon, whereas areas south and east of the boundary
will likely continue to experience diminished air quality. Accordingly, air
quality indices in the unhealthy for sensitive groups to unhealthy range are
expected to remain in Central and Southern Oregon through tomorrow afternoon,
with localized pockets of worse air quality possible immediately downwind of
the fires burning across the central and southern portions of the state.
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Near-surface smoke
forecast from the High-Resolution Rapid Refresh (HRRR) Model for Thursday,
August 23, 2018 at 4 p.m.
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Disclaimer: Forecasting weather, fire behavior, and
smoke transport and dispersion is challenging. While we strive to bring
you the most up-to-date and accurate forecasts, conditions can and do change
rapidly. Please take the appropriate action to protect yourself.