519
FXUS66 KMFR 200949
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
249 AM PDT Fri Sep 20 2024

.DISCUSSION...OVerall quiet conditions are expected over the next
several days, with upper level ridging overhead, a thermal trough
along the coast, and with a few exceptions, generally seasonable
weather across the region. With the ridge in control, the area
will remain dry until the mid-to-late next week, when the next
front may pass through the area.

Along the immediate coast, the thermal trough will continue to
produce gusty north winds, with occasional periods of fog and/or
low clouds as the marine layer make periodic inland pushes. These
clouds and fog will stay west of the coastal mountains, however,r
as the thermal trough will also result in a general dry, east
wind flow that will scour out much of the moisture and keep the
marine layer at bay. This same wind is likely to produce an
ongoing Chetco Effect as well, keeping temperatures warmer than
normal along the south coast near Brookings,

Inland, temperatures will remain around or just above normal for
this time of year, which means the first day of Fall on Sunday
will feel like a typical day in mid-September. Fall will not
arrive for good, however, when temperatures jump back up to
summertime values Tuesday and Wednesday as the upper level ridge
axis amplifies and passes overhead, making those days feel more
like late July or early August.

As mentioned above, this dry pattern may change a bit with the
arrival of a front around Thursday. This system appears pretty
weak in the latest models suites, with little in the way of
moisture content, and with much of the energy well to our north.
So, other than some light rain possible along the coast and into
the Umpqua Basin, the passage of this system looks like it will
do little more than bring temperatures back down to more
seasonable values as we head into next weekend. -BPN

&&

.AVIATION...20/06Z TAFS...Overall, we expect VFR to prevail
across a large portion of the forecast area through Friday evening,
including at Roseburg, Medford and Klamath Falls.

Patchy marine stratus could impact the North Bend terminal for
a few hours late tonight and satellite imagery is showing some to
the north over Tillamook, heading south. Models still are showing a
slight offshore (NE) wind component, which may prevent the
stratus from reaching the airport. We`ve left in a temporary BKN010
ceiling 09-12Z, these but shouldn`t be long-lived, if they occur at
all. Expect VFR to prevail during the day Friday, but gusty north
winds (25-30kt) will redevelop in the afternoon. There is a chance
some MVFR ceilings also develop during Friday morning at Roseburg,
but these should also be brief and only a few hours at most.
-Spilde

&&

.MARINE...Updated 230 AM Friday, September 20, 2024...A thermal
trough pattern will likely persist through early next week. This
will result in the strongest northerly winds south of Port Orford
during the afternoon and evening hours, with very steep seas and
occasional gale gusts at least into Saturday evening. Meantime,
steep seas and advisory strength northerly winds are expected north
of Port Orford.

The thermal trough is forecast to move inland with weakening winds
and easing seas late Tuesday into Wednesday. -Spilde/Hermansen


&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT
     Saturday for PZZ350-356-370-376.

Hazardous Seas Warning until 11 PM PDT Saturday for PZZ356-376.

&&

$$