FXUS66 KMFR 092341
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
342 PM PST Thu Jan 9 2025

.DISCUSSION...Satellite image shows low clouds hanging tough in the
Umpqua Basin, and Grants Pass area. The low clouds could linger in
these areas for the rest of the afternoon with brief clearing
towards 4-5 pm before the low clouds return later this evening.
Elsewhere it's clear. Dry weather will continue through tonight.
High and mid mid clouds will increase later tonight as an upper
trough and front approaches the coast, but it won't be enough to
keep low clouds and fog from forming in the same areas as this
morning.

A cold front will push into the area Friday morning into Friday
afternoon bringing an increasing chance of precipitation with the
best chance along the coast, north of the Umpqua Divide and
Cascades. Friday morning. Precipitation amounts will also be highest
in these areas, but were not expecting anything significant.
Basically the garden type variety. Farther southeast, including the
Rogue Valley could end up dry during the morning hours with
precipitation arriving towards midday into the afternoon. Rainfall
amounts in the Rogue Valley will be between 0.10 and 0.15 of an
inch.

The front will move east of the Cascades later in the afternoon and
showers will gradually diminish. Precipitation east of the Cascades
will be hit and miss with not much in the way of precipitation
amounts. It will be windy there Friday afternoon and evening, but
not strong enough to warrant any advisories.

Showers will linger Friday night, mainly along and north of the
Umpqua Divide and Cascades, but they will also generally diminish
during the overnight hours.

Most locations will be dry Saturday as upper ridging nudges into the
area, but we'll still remain in a somewhat moist north to northwest
flow. Therefore isolated showers are still possible for the northern
Cascades. A sprinkle or two cannot be ruled out north of the Umpqua
Divide, that should be the exception and not the rule.

Saturday night into Sunday will be dry. There's some evidence
showing a weak shortwave dropping into the area SUnday afternoon,
but the trajectory of the upper trough is one that does not
typically result in precipitation. Saturday night skies will clear
out and that will set the table for a return to low clouds and
patchy to areas of freezing fog for many of the interior westside
valleys.

The consensus is for strong upper ridging building over the Pac NW
Monday through at least the end of next week. The stable weather and
already saturated ground will result in low clouds and patchy to
areas of fog and freezing fog for the westside valleys. Also gusty
east breezes are possible near and at the ridges along the Cascades,
the coastal mountains in southwest Oregon and western Siskiyou
County later in the evening and overnight hours starting Monday
evening. -Petrucelli


&&


.AVIATION...10/00Z TAFS...Areas of IFR low clouds remain in the
Scott Valley, the Rogue Valley west of Grants Pass, and the Umpqua
Basin near Roseburg late this afternoon. What hasn't broken this
afternoon will remain and fill in again with LIFR this evening.
Expect LIFR to return to Medford late this evening/overnight. The
next front will approach the coast late tonight. This will bring
lowering ceilings and visibility (probably MVFR) to the coast by
early Friday morning along with some light rain/drizzle. The front
will move inland and this should lift the LIFR conditions at
Roseburg to MVFR as light rain begins (~16Z) Friday morning. It will
probably take most of Friday morning to do this at Medford, but
expect a similar scenario there with a good chance (>60%) of at
least a little light rain Friday afternoon. Over the East Side, VFR
prevails through Friday morning. Local MVFR ceilings could develop
across the north Friday afternoon along with some light rain/snow,
but precip chances at Klamath Falls are generally 30% or less.
-Spilde


&&

.MARINE...Updated 200 PM PST Thursday, January 9, 2025...Quiet
conditions continue through tonight. A cold front will move
through Friday morning followed by another steep west swell and
conditions hazardous to small craft Friday afternoon through
Saturday. North winds strengthen late Saturday into Sunday as high
pressure builds offshore and a thermal trough develops near the
coast. Winds should remain just below gales during this period,
but steep to very steep seas are likely, highest south of Cape
Blanco. -Spilde


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Air Stagnation Advisory until noon PST Friday for ORZ023>026-
     029>031.

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory from 10 AM Friday to 4
     PM PST Saturday for PZZ350-356-370-376.

&&

$$