048
FXUS66 KMFR 110324
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
824 PM PDT Thu Apr 10 2025

.UPDATE...Updated Marine Discussion.


&&

.MARINE...Updated 800 PM Thursday, April 10th...Winds will become
northerly overnight. There`s good agreement that a thermal trough
will develop along the south Oregon coast Friday with north winds
increasing starting late Friday morning. The thermal trough is
likely to remain a play maker for most of the weekend with winds and
seas highest south of Cape Blanco. Small craft conditions are likely
from late Friday morning through Saturday afternoon, with small
craft conditions extending into the northern waters Saturday evening
into Sunday.

Winds and seas will be highest in the southern waters through the
weekend and it`s possible winds could reach low end gales Saturday
afternoon and evening south of Gold Beach, but confidence is not
high enough to go with a gale warning just yet. However, Hazardous
Seas Warning conditions are likely and a Hazardous Seas Warning has
been issued.

There`s some signs winds will ease slightly Sunday then moreso on
Monday, but we`ll still likely have at least Small Craft conditions.
There`s fairly good agreement that moderate to north winds will
persist into most of next week with a "classic thermal through"
pattern that is typical of the summer months, but can sometimes
occur this time of the year. Winds will be strongest south of Cape
Blanco during this time with at least Small Craft conditions.


&&

.PREV DISCUSSION... /Issued 429 PM PDT Thu Apr 10 2025/

UPDATE...Updated Aviation Discussion.

AVIATION...11/00Z TAFs...Along the coast, a mix of IFR and MVFR
conditions will persist through early Friday morning, lifting to
mainly MVFR with local IFR late Friday morning, then clearing to VFR
Friday afternoon.

Inland, west of the Cascades, conditions are mainly VFR late this
afternoon/early this evening except for MVFR ceilings in northwest
Douglas County.  Gusty surface winds will persist early this
evening, then lower late in the evening. MVFR ceilings will spread
across Douglas, Josephine and northern Jackson counties this
evening, including Roseburg (KRBG) and Merlin/Grants Pass. Then,
MVFR conditions will become widespread with local IFR from the
Southern Oregon Cascades west (including at Medford, KMFR) and in
far western Siskiyou County with generally VFR elsewhere east of the
Cascades and in central/easter Siskiyou and Modoc counties in
Northern California. Mountain obscurations are expected to develop
this evening, especially from the Cascades west, and persist through
Friday morning. Conditions will gradually lift to VFR late Friday
morning into early Friday afternoon.

PREV DISCUSSION... /Issued 209 PM PDT Thu Apr 10 2025/

DISCUSSION (Today through Wednesday)...

Overview:

Overall, the forecast remains at a "low impact" level for the next
several days. Items of interest include the light rainfall
today/tonight mainly along the coast and north of the Umpqua
divide where the highest chances are for accumulation are
located, and the frost/freeze potential this weekend. Otherwise,
we will have some breezy days mixed in but nothing stands out for
any type of advisory or warning level. Lastly, one trend recently
was the decrease in rain chances later in the forecast are now
gone, so we are looking at a stretch of dry weather starting this
weekend and going into at least middle of next week.

Further Details:

Water vapor imagery shows a couple noteworthy features. There is a
fetch of moisture riding northeast on the backside of an exiting
ridge of high pressure. This has allowed for increased cloud cover
and showers along and near the coast this afternoon. We are
expecting this to continue through the evening. Not expecting much
in the realm of accumulations, but some areas could pick up a couple
tenths of an inch, but the highest amounts could be closer to half
an inch in Curry County by the time rainfall ends late
tonight/tomorrow morning. The aforementioned ridge of high
pressure will continue to push east and south through the weekend
before another ridge builds into the PacNW. The orientation and
location of this ridge will likely block and/or force incoming
troughs/shortwaves around the MFR forecast area through he
weekend. Even if we happen to get some glancing blows from the
dynamics associated with these shortwaves, rainfall amounts will
be feeble if nonexistent across our area as it stands now. The
bigger story may be next week when well above normal temperatures
(10+ degrees for some areas) are forecast starting as early as
Sunday and going through much of the week. For example, Medford
could be 15+ degrees above normal on Monday where we have a high
of 81 forecast. The record for Medford on April 14th is 92, so
while we will likely not hit record temps, it is certainly a
noteworthy day from a temperatures standpoint.

The frost/freeze potential for the Rogue Valley has decreased
slightly from previous forecast with less areas seeing temperatures
below 32 degrees. Some of the higher elevation on the outskirts of
the valley may still see temps of 32 or slightly below. Frost (~33-
36) is not looking favorable from a moisture standpoint as morning
RH values may only reach 70 to 80 percent. That being said, there
will be areas this weekend on the westside that could still see
these frost/freeze hazards. Anyone with a garden or agricultural
interest may want to follow the forecast closely and monitor low
temperatures for your specific area.

Given the dry stretch starting Saturday and low afternoon humidity
values expected to start this weekend, we will have to monitor fuels
a little closely. This could cause some rapid curing in some areas,
especially areas that have not received a lot of moisture. Not
seeing any fire weather concerns at this point, but its that time of
year when we need to start preparing for fire season and looking
at the fuel status.

-Guerrero

&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory from 11 AM Friday to 5
     AM PDT Sunday for PZZ350-356-370-376.

Hazardous Seas Warning from 11 AM Friday to 5 AM PDT Sunday for
     PZZ356-376.

&&

$$