484
FXUS66 KMFR 281554
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
854 AM PDT Tue May 28 2024

...Updated Marine Section...


.MARINE (Updated at 8:45 AM)...A weak swell and light wind speeds
will lead to relatively calm conditions over the waters today. By
tomorrow, a thermal trough will strengthen and gale force winds
are possible by late afternoon/early evening. Come Thursday, we
will likely see the strongest wind speeds over the waters for the
week with gale force winds likely. The probability for reaching
at least gale force winds on Thursday is around 50-95% south of
Cape Blanco. The probability is highest across our southern waters
(85-95%) on Thursday where gale force winds are most likely. We
are anticipating relatively calmer seas by the weekend and into
early next week as the thermal trough starts to break down on
Friday.

-Guerrero

&&

.PREV DISCUSSION... /Issued 500 AM PDT Tue May 28 2024/

..Updated AVIATION discussion...

DISCUSSION...Satellite imagery is showing some lower stratus
along the coast and in the Coquille Valley and entering the Umpqua
basin. Additionally, higher clouds associated with a frontal
boundary remain offshore but are starting to fill in inland. There
were a few thunderstorms yesterday east of the Cascades, and the
area remains relatively moist. Additional showers and a few
thunderstorms will be possible once again. Showers and storms are
expected mainly across portions of the East Side, with a few
showers occurring offshore and along northern Coos and Douglas
Counties. However, most precipitation will be occurring north of
our area.

This front will push through southern Oregon tonight and it will
also bring breezy west winds this afternoon and evening.
Overnight, the lingering showers will dissipate. Temperatures
today and Wednesday will be a bit cooler as well, but frost and
freeze concerns are not expected.

Conditions will dry out Wednesday into Saturday as a ridge of
high pressure returns. This will help warm us up and dry us out
once again.

Then on Sunday into Monday, the next front will approach the
Pacific Northwest and northern California. This front will have
the potential to bring additional light precipitation to the area
with showers in the forecast. Ensembles have large variations
about the timing and strength of the front, but will go with the
national blend of models for now. This front may bring
temperatures back toward normal; but these details are likely to
emerge as we get closer to that time frame. -Schaaf

AVIATION...28/12Z TAFs...An upper trough is bringing some cloud
cover to the Oregon coast and Umpqua Valley this morning. Levels
over North Bend and Roseburg move between VFR and MVFR as ceilings
shift. Ceilings over areas farther inland are expected to stay at
VFR under high ceilings, but gusty winds are forecast for this
afternoon especially east of the Cascades. While widespread showers
are not expected, slight thunderstorm chances (10-15%) will be
present over Lake, Modoc, and eastern Siskiyou counties this
afternoon and evening. Winds and thunderstorm chances will decrease
overnight, but some amount of cloud cover will persist through the
TAF period especially over coastal areas. -TAD

MARINE...Updated 230 AM Tuesday, May 28, 2024...Relatively calm
conditions will continue today. Northerly winds will turn westerly
this morning as an upper trough passes to the north. Swell will
increase slightly, but remain unimpactful.

A thermal trough will develop under upper level ridging on Wednesday
afternoon, driving conditions through the rest of the week. North
winds will return and bring wind-driven steep and very steep seas to
all marine waters. Sustained winds will be in the 20 to 35 kt range
at their highest, with the strongest winds expected south of Cape
Blanco especially on Thursday afternoon and evening. Chances for
gale gusts south of Cape Blanco will be very high (50-90%) from
Wednesday afternoon through Friday afternoon, and there is a lesser
(10-50%) chance of gales over the outer waters north of Cape Blanco
as well. A Gale Watch is in place from Wednesday evening through
Friday evening for all waters south of Cape Blanco where the chances
are highest for gales. Meanwhile, steep seas and conditions
hazardous to small craft are likely for all areas north of Cape
Blanco during this time.

Conditions could improve next weekend as a pattern change disrupts
the thermal trough, and winds ease. -TAD/BR-y

&&

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

PACIFIC COASTAL WATERS...Gale Watch from Wednesday afternoon through
     Friday afternoon for PZZ356-376.

&&

$$