Dorris, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

855
FXUS66 KMFR 091320
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
520 AM PST Sat Nov 9 2024

.DISCUSSION...Dry weather continues today. Then, a weak front will
approach the coast late this afternoon and move inland this
evening and tonight. This front will bring light precipitation,
mainly along the coast and inland, mainly for areas from the
Cascades west. Precipitation amounts are expected to be light
(generally, a 0.10 inch or less for inland areas and 0.25 inches
or less along the coast).

Westerly flow aloft will persist on Sunday. A low pressure system
in the Gulf of Alaska will bring a frontal system into the area
late Sunday into Monday. Models and ensembles show good agreement
on the timing of this front, bringing warm front into western
portions of the area late Sunday and Sunday night. This will bring
mainly light precipitation to western portions of the area. Then,
this is followed by a strong and moister cold front on Monday.
Moderate to heavy precipitation and gusty winds are expected with
this front. Models indicate a 45-55 kt southwesterly 700mb jet
will move over the area Sunday night into Monday. This will allow
a potential for gusty southerly to southwesterly winds to develop
in the Shasta Valley and areas east of the Cascades, especially
over the higher terrain and in the Summer Lake area. The National
Blend of Models supports a 40-60% chance of winds gusting to 45
mph or higher over the higher terrain near Summer Lake and a 25%
chance for winds gusting to 45 mph in the Shasta Valley. Gusty
winds are likely along portions of the coast Sunday night, with a
30-60% chance for winds gusting to 45 mph for higher areas along
the coast from Cape Blanco southward.

As this front moves across the area, precipitation will likely be
heavy along coastal areas with widespread moderate to heavy
precipitation inland. The National Blend of Models continues to
indicate 1-2 inches of rain along the coast (90-100% chance of 1
inch along the Coos, Douglas and Curry Co. coasts and 50-75%
chance for 2 inches of rain for areas along along the Curry Co.
Coast) with the frontal passage, followed by more rain in showers
Monday night into Tuesday. For the event, there is a potential
(40-60%) chance for 3 inches or more of rain to fall in the Curry
coast ranges Sunday night through Tuesday.  Inland, expect
widespread moderate to locally heavy precipitation, with storm
totals ranging from 0.25 to 1.5 inches across much of the area,
heaviest in Douglas, Joesphine, western/southern Siskiyou counties
as well as in the Southern Oregon Cascades. Additionally, models
indicate sufficient upper level support and instability to support
a slight chance (20%) for thunderstorms to develop along the coast
and into the Umpqua with and behind the frontal passage Sunday
night through Monday night.

Snow levels are expected to be 7000-7500 feet ahead of the front,
lowering quickly to 4500 to 5000 ft with the frontal passage.
Moist onshore flow behind the front will allow numerous showers,
heavy at times in the Southern Oregon Cascades, Monday evening
into early Tuesday. There is a potential (30-60%) for periods of
high snowfall rates (near 1"/ hr at times) in the Cascades above
5000 feet for areas north of highway 140 on Monday and into Monday
night. Snow levels will lower down to around 4500 feet Monday
night into Tuesday morning as showers continue. Moderate snow
impacts are possible in the south-central Oregon Cascades,
including Crater/Diamond Lakes and Highway 58 near Willamette
Pass. We will continue to evaluate this period and update the
forecast as confidence increases in the details for this period.
South of highway 140 in the Cascades, for the mountains in
Northern California and for areas east of the Cascades, lighter
snow impacts are expected, with limited impacts possible along
Highway 140 near Lake of the Woods and Highway 97 north of
Chiloquin.

&&

.PREV EXTENDED DISCUSSION... /Issued 251 PM PST Fri Nov 8 2024/

DISCUSSION...There should be a bit of break between systems
Tuesday afternoon/evening as the upper flow reorients from NW to
SW. Another windy, wet frontal system will then arrive Tuesday
night into Wednesday which should bring another round of moderate
to heavy rainfall to the coast. Despite the earlier rain, we
aren`t too concerned about flooding (other than nuisance variety,
ponding of water, poor drainage areas, etc), since it`s still
early in the season and rivers/streams/creeks are running low at
the moment. River basins and tributaries west of the Cascades will
likely see rises though due to the influx of new water.

Due to the orientation of the flow, uncertainty exists in the
intensity of precipitation as it moves inland Wednesday (NE
California and our eastern deserts could have to wait longer for
the precip with this second front). And, snow levels still appear
to be fairly high at midweek, mostly 5000 feet and above. But,
the active weather pattern will continue late next week as an
upper level trough appears to be the dominant weather feature
Thu/Fri. We may get another break toward next weekend as this
trough pushes eastward, but confidence in that is low at this
time. -Spilde

&&

.AVIATION...09/12Z TAFS...Upper level clouds are keeping the fog
from building into TAF locations this morning. Look for some light
winds and plenty of high clouds through the day ahead of a weak
front. VFR conditions seem pretty likely through the morning. The
chance of rain will increase along the coast later this evening,
although models are pretty confident ceilings will remain at VFR
levels over inland locations with some MVFR ceilings along the
coast.

-Smith

&&

.MARINE...Updated 200 AM PST Saturday, November 9, 2024...

Sub-advisory conditions will continue though early Saturday, though
seas will gradually increase tonight into Saturday as the pattern
becomes more active. Two fronts will move through this weekend, one
later this afternoon/evening and another Sunday night into Monday.

The first front, the weaker of the two, will bring increasing south
winds tonight into Saturday with building westerly swell. This will
result in conditions hazardous to small craft for much of the outer
waters Saturday afternoon and evening north of Cape Blanco, since
combined wave heights will approach 10 feet. Farther south, where
winds will be lighter, seas will be swell dominated and remain
mostly below 10 feet. That front will stall and dissipate over the
waters Saturday night.

The second front, the stronger one, moves through late Sunday into
Monday. This will likely bring a period of moderate to heavy rain,
gales, and very steep and chaotic seas. Latest forecast has wind
gusts up to 40 knots over the waters and perhaps 45 knots off the
coast of Port Orford. Models also continue to show this system being
followed by another large, long period swell, peaking around next
Tuesday. Early indications are showing peak swells 17-21 feet with a
period of 15-16 seconds. This would maintain very high and very
steep seas through midweek. -Smith

&&

.BEACH HAZARDS...Updated 200 PM PST Friday, November 8, 2024...

Another large, long period swell is expected to arrive early next
week. Model guidance has been consistently showing NW swells
arriving following the front Sunday night into Monday. Seas briefly
subside immediately behind the front Monday (6 hours or so during
the morning), but then build significantly Monday afternoon and
Monday night, reaching a peak of 17-21 feet, 16 seconds by early
Tuesday morning. This will bring large breaking waves (23-27 feet)
to the beaches and coastline through Tuesday afternoon. Seas will
gradually subside Tuesday night. This may result in a high surf
advisory at some point.

Large breaking waves create hazardous conditions along and within
the surf zone, and could inundate beaches and low lying shorelines.
If you have plans to venture out to the beaches early-mid next week,
pay close attention to the ocean, stay away from the surf zone and
off of jetties. Also, keep checking back for forecast updates.
-Spilde/BPN

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...CA...None.

PACIFIC COASTAL WATERS...Gale Watch from Sunday afternoon through
     Monday morning for PZZ350-356-370-376.

Small Craft Advisory from 10 AM this morning to 10 PM PST this
     evening for PZZ370-376.

&&

$$