NWS Medford, OR wrote its last area forecast discussion before the first event at Jul 12, 2:50 AM PST, 2 hours 10 minutes earlier.
Area forecast discussion, Jul 12, 2:50 AM PST, 2 hours 10 minutes before
Area Forecast Discussion
National Weather Service Medford OR
350 AM PDT Mon Jul 12 2021
.DISCUSSION...Hot, dry, and breezy conditions are expected to
continue through mid week as a thermal trough slowly moves
eastward over the next couple of days. The expected heatwave,
however, has been somewhat dampened by the smoke coming from area
wildfires. Areas without a lot of smoke, like Alturas and Montague
have seen hot temperatures upwards of 100 degrees. Areas that are
experiencing heavier smoke have seen realized temperatures a few
degrees lower than their maximum possible. This will continue
through Tuesday before the thermal trough exits our area. Even
though temperatures may not be realizing their potential, the
presence of smoke will keep folks from experiencing relief, and
our heat advisories and excessive heat warnings will be allowed to
continue. Please see the NPWMFR for more details.
Additionally, smoke from the Jack and Bootleg fires are blanketing
most of the area east of the Coast range. An air quality alert
exists for Oregon, issued by the department of environmental
quality; and imagine that it will probably be extended for many
areas for the foreseeable future. The HRRR smoke models has been
doing pretty well at predicting the smoke, and suggests that the
coast has been relatively unaffected by the smoke (and also the
heat), so it is the perfect place to go in order to escape these
pervasive conditions.
The smoke helped subdue some of the unstable nature of the
atmosphere today, however a pyrocumulus was observed on the
Bootleg and briefly on the Jack fire signifying just how unstable
the atmosphere is despite the amount of smoke helping to stabilize
things. Additionally, satellite imagery was picking up on the
Bradley Fire near McCloud. Expect smoke from this fire to pick up
and travel into Modoc County.
Lastly, expect periods of breezy afternoon winds through
Wednesday. This is particularly true east of the Cascades.
Conditions will begin to improve midweek as temperatures come back
toward normal under an upper level trough. The good news is that
this trough is located far enough west that it should not draw up
the monsoonal moisture in the desert southwest, nor should we have
enough southwest flow to bring in moisture from the ocean.
Although it means no precipitation, it also means no thunderstorms
are in the forecast. Unfortunately, the near-normal conditions
will likely be short-lived as the next thermal trough will build
offshore and push inland over the weekend in next week. -Schaaf
&&
.AVIATION...For the 12/12Z TAF Cycle...Over the coastal waters,
along the coast, and in the coastal valleys...Widespread IFR cigs
with areas of IFR vsbys will burn back to the coast by late Monday
morning, then return to the same areas Monday afternoon and evening.
The lower conditions will then prevail into Tuesday morning. Over
the remainder of the area...Smoke from the Jack and Bootleg fires
are creating areas of MVFR/IFR visibilities, especially east and
northeast of the fires. Most areas east of I-5 are seeing at least
some reductions in visibility due to haze and smoke. These
conditions will persist into at least Tuesday morning. -BPN
&&
.MARINE...Updated 200 AM PDT Monday 12 July 2021...A strong
thermal trough near the coast will producing strong north winds and
choppy wind-driven steep seas across the area. Gale force winds and
very steep seas will occur offshore south of Cape Blanco, peaking in
strength during the afternoons and evenings. The thermal trough will
weaken Wednesday night into Thursday, and winds and seas will
decrease at that time. -BPN
&&
.FIRE WEATHER...300 AM Monday July 12, 2021...The overall pattern
is not expected to change much through at least the middle of
next week. This means we can expect much of the same with
continued dry and hot conditions for all locations away from the
coast.
There are two main concerns in the short term. One, is a high Haines
later this afternoon into this evening with a Haines 6 expected
within the perimeter of the Bootleg Fire with pyrocumulus likely
later in the afternoon. High Haines are also expected in eastern
Fire zones, 624, southern 625, all of 280, 282, and 285 and
eastern 284. This includes the Bradley, Juniper, and Coyote
Fires. Moderate Haines (5) is expected elsewhere away from the
coast, including the Jack Fire. Second is the dry and gusty winds
leading to Red Flag conditions to be met later this afternoon and
evening in fire zones 285. A weak upper trough will swing north
of the area and this could result in a slight uptick in winds
while relative humidities remain near or in the single digits.
Therefore a red flag warning has been issued for the Modoc
National Forest in Fire Zone 285 from 2pm to 9 pm PDT. Please see
RFWMFR for more details.
For those folks in evacuation zones near the Bootleg Fire, we
want to stress how dangerous of a situation this is, and you will
be much safer well away from the fire. If you live in a level 2
evacuation zone, consider evacuating early, or at the very least
go over your fire evacuation plan and gather your go kits so you
can leave at a moment's notice.
Elsewhere east of the Cascades, we'll continue to headline for
breezy winds and low relative humidity this afternoon and evening
and again tomorrow afternoon and evening. Could not rule out a few
isolated locations briefly touching Red Flag conditions during
these times.
Meanwhile the thermal trough pattern along the south Oregon coast
will continue for the next couple of days, this will result in
moderate to locally poor overnight recoveries at the mid slopes
and ridges in fire zones 618, 619, western 620 and western fire
zone 280 in California. Guidance suggest breezy east to northeast
winds, except for fire zone 280.
Mid to late next week, we'll see an increase in troughiness the area
resulting in gradual cooling, slightly higher relative humidities,
and increasing winds across much of the area. -Schaaf/Petrucelli
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Heat Advisory until 8 PM PDT Tuesday for ORZ029>031.
Heat Advisory until 8 PM PDT Tuesday for ORZ024-026.
CA...Excessive Heat Warning until 8 PM PDT Tuesday for CAZ080>082.
Heat Advisory until 8 PM PDT Tuesday for CAZ083>085.
Red Flag Warning from 2 PM this afternoon to 9 PM PDT this
evening for CAZ285.
Pacific Coastal Waters...Small Craft Advisory until 11 PM PDT Wednesday for
PZZ350-356-370-376.
Gale Warning until 11 PM PDT Wednesday for PZZ356-376.