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000
FXUS66 KMFR 180359
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
859 PM PDT Wed Apr 17 2024

.DISCUSSION...An update is not necessary. Slightly below normal
low temperatures and slightly above normal high temperatures
resulted in a relatively normal Wednesday. A strong ridge offshore
will push into the area Thursday and Friday, continuing the
warming trend.

A weak front will push to the coast Saturday with a chance of
light rain for Coos, Curry, and Douglas counties northward, and a
slight chance late in the day into Josephine County. Elsewhere, it
will still have enough strength to bring an increase of clouds,
start a slight cooling trend, and produce widespread breezy,
gusty afternoon west to northwest winds at 10 to 20 mph with gusts
of 15 to 35 mph.

Weak ridging is likely to follow Sunday through Monday with a
resumption of a warming trend and seasonably breezy 8 to 15 mph
afternoon winds.

A slow moving upper level low is expected to produce a more
active, cooler and wetter pattern beginning around Tuesday or
Wednesday.

&&

.AVIATION...18/00Z TAFs...VFR ceilings and visibilities will persist
through the TAF period. Gusty northerly Winds along the coast
during Thursday afternoon are the only weather hazard in this TAF
period.

-Smith

&&

.MARINE...Updated 800 PM Wednesday, April 17, 2024...Winds will drop
below gales later tonight.  A thermal trough will bring strong gusty
north winds and steep seas to all waters through Thursday. These
conditions will still remain hazardous to smaller crafts on
Thursday. The thermal trough weakens by Friday and conditions will
improve. Relatively light winds and low seas continue into Saturday.
Gusty north winds and steep seas are expected to return later in the
weekend.

-Smith

&&

.PREV DISCUSSION... /Issued 226 PM PDT Wed Apr 17 2024/

SHORT TERM DISCUSSION...Tonight through Friday Night...The steady
dry and warming trend continues through the rest of the work week,
with high pressure building in overhead and a thermal trough
developing along the coast. This pattern is producing a general
east wind aloft, and this will then result in downsloping winds,
especially along the south coast near Brookings, and will allow
for strong overnight inversions for inland valleys. This means
that while daytime highs will be above normal for this time of
year, lows in the valleys will be cool. While we can not rule out
a few pockets of freezing temperatures tonight, widespread freeze
is not expected, with only an approximately 5 percent chance of
lows reaching 32 degrees or below. The next several nights should
be steadily warmer, so there is are no additional frost/freeze
concerns in the near term. -BPN

LONG TERM...Saturday through Wednesday...

Overview:

For this portion of the discussion--Saturday through Tuesday--the
only noteworthy item is the light rainfall expected along/near the
coast and across Douglas County Saturday and Saturday night.
Portions of far northern Lake County near the Douglas County boarder
will be in the mix as well for these chances. These chances are
around 20-60 percent with only light amounts (<0.10") expected. We
have another chance of ~30% or less for rain Tuesday into Tuesday
night. This later time period will also see chances for higher
elevation snow across the Cascades. In fact, this will be the start
of a broader and stronger system moving into the PacNW just beyond
this forecast period. Otherwise, seasonable temperatures, relatively
light wind speeds, and essentially no impacts are expected through
this stretch of the forecast. Of perhaps more note is the relatively
warm high temperatures for this time of year.

Further Details:

Focusing on the precipitation chances, the first system Sat/Saturday
night will only bring very light amounts of QPF to the forecast area.
The coast has the highest probability of accumulating rainfall, but
actual amounts are likely to be low with the probability of getting
more than 0.10"/12hrs at less than 10%. Additionally, the main
dynamics associated with this system are very far north, so if the
system shifts north at all we could miss out entirely. For the
opposite scenario of a southward shift, this doesn`t look to improve
our rain chances due to trajectory of the H5 trough. We would have
to see a major shift at 500mb to see higher rainfall amounts, but
confidence is not high for this given model agreement on this
track Sat/Sat night.

For the Tuesday system, we are only seeing the beginning of this
system at the end of this current 7 day forecast. Models are very
out of phase from one another at this point, so confidence is low on
the details. That said, the NBM is indicating a similar trend in QPF
amounts of 0.10" or more in 12hrs to be less than 10 percent. This
is a stronger and broader system with potentially a more impactful
track. Impacts would likely carry over into Wednesday and beyond
(outside this current forecast). Confidence is low on the details,
but this could very well be our next more widepsread impactful
system. We shall see over the coming days. -Guerrero

&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Friday
     for PZZ350-356-370-376.

Gale Warning until 11 PM PDT this evening for PZZ356-376.

&&

$$