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fxus66 kmfr 142118 
afdmfr

Area forecast discussion
National Weather Service Medford or
218 PM PDT Mon Oct 14 2019

Short term...this afternoon through Thursday night...low clouds
in the Umpqua basin are quickly eroding this afternoon and once
these clouds dissipate, skies will be clear across the whole
forecast area. Quiet weather with seasonable temperatures and dry
conditions will continue overnight and into Tuesday, with similar
cloud cover expected Tuesday morning as was experienced this
morning.

The weather becomes more active Wednesday and into the extended. A
seasonable front will make it's way into the forecast area
Wednesday. While this front isn't particularly strong, it is of
the more stronger variety compared to what has been experienced so
far this season. Although it will be more beneficial than
impactful, there will be breezy winds and periods of moderate to
heavy rain with this first front. Rain looks to arrive at the
coast late Wednesday morning, gradually moving inland through the
day. Over a 24 hour period (wednesday morning - Thursday morning),
rainfall totals look to be around 1.00"-1.50" along the coast
south of Cape Blanco, 0.50"-1.00" north of Cape Blanco, along the
Cascades, and in western Siskiyou County with 0.25"-0.50" expected
for inland areas west of the Cascades. East of the Cascades, and
south of the Siskiyous, expect generally less than a quarter of an
inch.

Snow levels will remain high during this front, around 7000-8000 ft,
and lowering to around 5000-6000 ft behind the front. By then the
bulk of the precipitation will be through, so minimal impacts are
expected due to snowfall Wednesday night into Thursday. Moderate
southwest flow with this system will bring some breezy conditions
along the coast and east of the Cascades. Current guidance
continues to keep winds just below advisory criteria, but gusts to
40 mph are expected east of the Cascades in the typically windy
areas (i.E. Summer lake).

Another front will move through late Thursday into Friday. This
front looks a bit weaker than wednesday's system, and the bulk of
the moisture will be directed north of the forecast area. Moderate
mid-level westerly flow will enhance precipitation along the coast
and Cascades Thursday night into Friday. Snow levels will hover
around 5000-6000 feet during this time, so again, impacts are
expected to be minimal and restricted to the Cascade passes. The
active weather continues as we head into the extended. /Br-y

Long term...Friday through Monday night...wet and cool weather is
expected late this week through the weekend. Model guidance has
slowed and trended slightly north in regards to the overall pattern,
which has decreased the coverage and amount of rain expected Friday
through Sunday night. However, a period of heavier, more widespread
precipitation is likely Saturday as one of the fronts pushes a bit
farther south as it moves onshore. Throughout the weekend, swift and
moist onshore mid/upper level flow will keep shower chances ongoing,
especially along the coast and over the mountains where upslope
winds will be strongest. Although temperatures will be slightly
below normal for this time of year, snow levels should remain above
5000 feet, if not much higher, throughout the extended term, so only
the higher mountain passes have the potential to see travel impacts
due to accumulating snow. -Bpn

&&

Aviation...for the 14/18z tafs...stratus with MVFR ceilings has
remained entrenched in the Umpqua basin and portions of the Illinois
and lower rogue valleys this morning. Local MVFR cigs are also
present over northern Klamath County, near Chemult and Crescent.
These areas have been slow to burn off today, but should clear by
early afternoon.

Elsewhere, VFR conditions are expected through the taf period. This
includes the north coast around koth due to persistent drying of the
air from offshore flow. -Bpn

&&

Marine...updated 200 PM PDT Monday 14 October 2019...calmer
conditions are expected this afternoon into Tuesday morning. Winds
will shift to the south as a cold front moves towards the waters
Tuesday. This will be the first in a series of stronger fronts which
are expected to move across the waters through late this week. Gusty
south winds and steep to very steep seas are expected with the first
front Tuesday night into Wednesday. Winds will be strongest from
Cape Blanco north and beyond 3 nm from shore with gusts approaching
gales. If nothing else seas will be wind driven and very steep with
hazardous seas conditions likely. Thus, a hazardous seas warning has
been issued.

Not long after the front moves onshore, a high and long period west
to northwest swell will build into the coastal waters Wednesday
night through Thursday evening. Guidance suggest swell heights
peaking out between 16 and 18 feet at 16 seconds Thursday into
Thursday evening before gradually diminishing late Thursday night
into Friday. Given the above mentioned scenario, a hazardous seas
watch has been issued for the heavier swell. Also a high surf
advisory has been issued.

Meanwhile small craft conditions are expected outside of the
hazardous seas warning and watch due to gusty winds and choppy wind
driven seas Tuesday night through Wednesday afternoon, then for the
higher swell Wednesday night through at least Thursday evening. For
details on all The Hazards, please see mwwmfr.

It's possible for small craft conditions to continue into Friday,
but there's still plenty of time to address this. -Petrucelli

&&

Mfr watches/warnings/advisories...
or...high surf advisory from 5 am to 11 PM PDT Thursday for
orz021-022.

California...none.

Pacific coastal waters...high surf advisory from 5 am to 11 PM PDT Thursday for
pzz350-356.
Small Craft Advisory from 11 PM Tuesday to 11 PM PDT Thursday
for pzz350-356-370-376.
Hazardous seas watch from late Wednesday night through Thursday
evening for pzz350-370-376.
Hazardous seas warning from 11 PM Tuesday to 5 PM PDT Wednesday
for pzz350-370.

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