696
FXUS66 KMFR 231641
AFDMFR
Area Forecast Discussion
National Weather Service Medford OR
841 AM PST Sun Feb 23 2020
.SHORT TERM...Satellite and radar show a front tracking inland
today. This front will bring generally light precipitation to
western and central portions of the area. This morning rain of a
few hundreths of an inch to around a tenth of an inch has been
observed along the coast and inland west of the Cascades. Amounts
have been more spotty in the Curry, Josephine and southern
Jackson county areas. Precipitation is spreading into the Southern
Oregon Cascades with light rain and snow. Snow will mainly affect
areas above 5000 feet elevation today. Accumulations may be very
light.
Light precipitation is expected to spread into northern Klamath
County today and areas of light precipitation are possible into
western Siskiyou. Otherwise, models continue to show eastern and
southeastern portions of the CWA will be mainly dry. West winds
are on track to increase and become strong and gusty over the
higher mountains and into portions of the east side, especially
across Lake County. Winds have increased this morning in the
Summer Lake area with gusts of 30 mph. Expect winds to peak this
afternoon and continue into the early evening with winds gusting
to 60-65 mph in the Summer Lake area. Breezy to gusty winds are
also expected across other area east of the Cascades today with
gusts of 30 to 40 mph. A wind warning and wind advisory are in
place for portions of the east side. Please see the NPWMFR for
details.
Showers will be spotty behind the front this evening, mainly
limited to the Southern Oregon Cascades and into Douglas and Coos
counties. Winds will lower late this evening and showers are
expected to taper off tonight as high pressure ridging moves into
the area.
&&
.AVIATION...For the 23/06Z TAF Cycle...A weak front will begin
moving towards the coastline overnight, with MVFR/IFR ceilings and
light rain spreading inland to the Cascades by morning, and into
portions of the East Side by afternoon. Terrain obscuration will
become widespread as well. For the coastal valleys and the Umpqua
Basin, a few hours of MVFR/IFR in fog or low stratus are expected
before the front arrives, but otherwise, the front itself will be
the primary cause of diminishing conditions.
Winds ahead of the front will become gusty over the coastal waters,
and along the coast, but will only gradually weaken by the end of
the TAF period. Strong winds are likely across the East Side as
well, and mountain wave turbulence here is highly likely during the
afternoon hours. -BPN
&&
.MARINE...Updated 200 AM PST Sunday, 23 Feb 2020...A cold front
approaching from the northwest will generate breezy winds and steeps
seas this morning. We'll see seas continue to increase later this
evening into tonight. Seas will be at their peak later tonight
hitting 15 to 18 feet in most locations. We'll see seas lower on
Monday and drop below small craft advisory thresholds Monday night.
Seas will then elevate Wednesday as another swell moves in from the
west. In addition, wind waves will build as a thermal trough
strengthens off the coast. Seas will likely be hazardous to smaller
crafts Wednesday night as the higher swell combines with northerly
wind waves south of Cape Blanco.
-Smith
&&
.PREV DISCUSSION... /Issued 314 AM PST Sun Feb 23 2020/
DISCUSSION...A shortwave disturbance will move north of the area
today. A cold front offshore this morning will move through
bringing mostly light precipitation with rain along the coast and
in the Umpqua Valley and some snow in the Cascades. Rain amounts
will be 0.10-0.25 of an inch for most areas along the coast
through Douglas County and into the Cascade Foothills, but up to
0.50 of an inch could occur in the Coast Ranges and in the
Cascades north of Crater Lake. South of those areas, less than
0.10 of an inch is expected, and we could miss out completely on
measurable precip here in Medford as will move of NorCal and areas
east of the Cascades. Snow amounts in the Cascades will only be
1-3 inches. But, the precipitation won't be the main impact. This
disturbance is packing some fairly impressive mid-level winds, so
expect westerly breezes to surface just about everywhere this
afternoon. Over the east side, though, expect some strong, gusty
winds nearer to the axis of the strongest 700mb flow. Latest
guidance is indicating the potential for 60-65 mph wind gusts this
afternoon over the higher terrain of the east side, but also
along Highway 31 between Summer Lake and Paisley. We have upgraded
the wind advisory to a high wind warning (NPWMFR) for that area,
while keeping the rest of the wind advisory intact. Wind gusts of
30-40 mph are possible at Klamath Falls, Lakeview and Alturas,
just outside of the advisory areas. Winds will subside this
evening and remaining showers will end overnight as the air mass
dries out and upper ridging offshore takes hold.
Overall, expect dry weather this coming work week with east winds
that will be strongest over the ridges at night and early in the
mornings. Some fog/low clouds will occur in the valleys during the
late night/morning hours. One weak system riding over top of the
upper ridge will disturb the flow pattern Tuesday night into
Wednesday, but won't have much noticeable effect on the sensible
weather. Large diurnal temperature variations, much like last
week, can be expected again with chilly mornings, and then milder
afternoons. The air mass will be a little warmer this time though,
so the mild afternoons should result in highs here in Medford in
the mid to upper 60s. A few of the higher ensemble members are
showing the possibility of 70+ degrees Thu/Fri.
There are a wide range of solutions heading into next weekend,
but at this time, the majority of the guidance indicates a break
down of the ridge with troughing moving back into the PacNW. This
would result in increasing chances for precipitation along with a
cool down. -Spilde
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory from noon today to 10 PM PST this evening for
ORZ030-031.
High Wind Warning from noon today to 10 PM PST this evening for
ORZ031.
CA...None.
Pacific Coastal Waters...Small Craft Advisory until 10 PM PST Monday for
PZZ350-356-370-376.
$$
CC
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