663
FXUS66 KMFR 172329
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
429 PM PDT Tue Sep 17 2024

...Updated AVIATION discussion...

.DISCUSSION...RADAR imagery is showing a band of showers beginning
to push across portions of southern Oregon and northern California
from the west. This is part of a low pressure system and
associated frontal boundary which will be pushing southward across
our area later today and tonight. This will keep precipitation
chances relatively high, particularly along and west of the
Cascades with the highest focus along the coast and north of the
Rogue-Umpqua divide. Still all areas should have at least a 15%
chance for precipitation with some wetting rain possible.
Meanwhile, temperatures will be mild during this time.

Showers will begin to taper off from north to south on Wednesday
and then we will begin a warming and drying trend. Over the
weekend, we`re going to see a weak front pass to the north of our
area, focusing precipitation to back along the coast and north of
the Rouge-Umpqua divide.

After that, we then continue the warming and drying trend as a
ridge of high pressure returns to the area. In general, we are
expecting still mild temperatures closer to normal next week.

-Schaaf

&&

.AVIATION...18/00Z TAFS...Showers are moving across northern
California and southern Oregon as a low pressure system moves south
over the Pacific. Thunderstorm chances remain higher (15-30%) over
the water, with lower chances (10-15%) west of the Cascades. Showers
can locally lower visibilities and ceilings as well as obscure
terrain, while thunderstorms can bring lightning and gusty, erratic
winds.

Showers and cloud cover will continue through early Wednesday
morning. Skies over most areas will clear out quickly, bringing VFR
conditions. Levels are expected to drop along the Oregon coast and
in the Umpqua Valley overnight and into Wednesday morning, with IFR
levels expected along the coast and possible in the Umpqua Valley
although MVFR is more likely in the valley. These areas could remain
under lower levels into Wednesday afternoon. -TAD

&&

.MARINE...Updated 200 PM Tuesday, September 17, 2024...A low
pressure system will move south over the Pacific today through
Wednesday morning, bringing chances for showers (40-90%) across
all waters. Thunderstorm chances (15-30%) will share the same
timing, with the highest chances at and beyond 60 nm from shore.
Chances for both will decrease quickly into Wednesday morning.

Stable atmospheric conditions are expected to build a persistent
thermal trough through the rest of the week and into the weekend.
Northerly winds will build steep seas south of Cape Blanco on
Wednesday evening, with steep seas moving into northern waters
through Thursday and Friday at least. Areas of very steep and
hazardous seas are possible south of Gold Beach through Thursday and
Friday as well. A Hazardous Seas Watch is in place for Thursday
afternoon through Friday evening for current areas where very steep
seas are expected, but additional guidance will help to solidify the
timing and area of these conditions.

Some amount of unsettled seas look to continue through the weekend
and into next week. Northerly winds will continue into next week but
will decrease, so the severity and coverage of future hazards is
likely to decrease. -TAD


&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory from 5 AM Thursday to 5
     PM PDT Friday for PZZ350-370.

Small Craft Advisory from 5 PM Wednesday to 5 PM PDT Friday for
     PZZ356-376.

     Hazardous Seas Watch from late Wednesday night through Friday
     afternoon for PZZ356-376.

&&

$$