Freeze Warning 6, NWS Medford, OR

Area Forecast Discussion
National Weather Service Medford OR
339 AM PDT WED OCT 19 2016

.DISCUSSION...There will be some patchy fog in the valley this
morning with the abundance of moisture from the days of heavy
rain. However, with the still warm soil temperatures warmer than
the dewpoint most of the fog is lifting to a low stratus deck in
the bottom of the valleys. This will lift by late morning giving
the region a warm break in the action ahead of the next system
that moves into the coast with a warm front bringing precip into
the coast waters but should be limited to northern portions as the
warm front washes over the top of an upper level ridge. The ridge
flattens Thursday morning ahead of the cold front that moves
inland Thursday, but the the ridge remains just to the east and
the front stalls over the area Thursday night into Friday night.

On Saturday the gfs and ecmwf are in fairly good agreement with
another moderate upper level low with nearly the same position and
depth of the surface lows, 996 with the ECMWF at 48N and 128W, and
993 double low with the GFS with the combined centroid at 47N and
130W. The upper low slowly moves east and inland Tuesday morning,
moving system after system out of it like a gumball machine
dispensing gumballs, bring wave after wave of gusty winds and
moderate rain throughout. None of these systems looks especially
strong, and with no atmospheric river event currently indicated
excessively wet. However, the addition of these systems will add
to an already wet October. Colder air aloft will begin to be
pulled in starting Sunday night, brining snow levels down enough
to possibly see snow at lower elevations east of the Cascades
Tuesday and Wednesday morning briefly. Significant additions to
the higher elevation snow pack Monday through Wednesday are
possible. Sven

&&

.AVIATION...19/06Z TAF CYCLE...A warm front offshore will send mid
and high clouds into the area late tonight into Wednesday, which
should help to limit low clouds/fog in some areas. However, the
longer nights this time of year and recent rainfall both also
increase the probability of low clouds/fog developing in the
valleys. So, we have indicated areas of IFR, to include KRBG and
KLMT TAFs overnight into Wednesday morning. KOTH and KMFR could also
see some low cloud/fog patches develop toward morning. Expect VFR
all areas by late morning. Any showers from the front should hold
off at the coast until Wednesday evening. -Spilde/Wright

Note: The ceilometer at FAA site KOTH is out of service, so there
will be no ceiling observations available generally between the
hours of 04Z and 14Z.

&&

.MARINE...Updated 230 PM PDT Tuesday, October 18, 2016...
Steep west swell will bring conditions hazardous to small craft
through early Wednesday morning and then will subside. A warm
front will move through Wednesday with light to moderate
southerly winds, highest north of Cape Blanco. A cold front is
expected to stall briefly over the area on Thursday before moving
onshore Thursday night into Friday. Another high and steep west
swell is expected Friday afternoon through Saturday. The next
strong front will arrive Sunday and eventually move onshore
Monday. -Spilde

&&

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

CA...None.

Pacific Coastal Waters...Small Craft Advisory for hazardous seas until 5 AM PDT early
     this morning for PZZ350-356-370-376.
     Small Craft Advisory from 2 PM this afternoon to 5 AM PDT
     Thursday for PZZ370.

SBN/SBN/SBN