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000
FXUS66 KMFR 172126
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
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 Tuesday...

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 too 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

&&

.AVIATION...17/18Z TAFs...Other than a few clouds that, so far, are
burning off this afternoon, clear skies are present across the
entire region with VFR conditions expected through the TAF period.
Gusty north winds up to 30 kt can be expected along the coast
(including North Bend) this afternoon and early this evening.
Occasional gusty north winds (up to 20 kt) are also anticipated at
Roseburg and occasionally in areas east of the Cascades this
afternoon.
-Spilde/CSP

&&

.MARINE...Updated 200 PM Wednesday, April 17, 2024...A thermal
trough will bring strong gusty north winds and steep seas to all
waters today through late this evening. Gales and very steep wind
driven seas can be expected south of Cape Blanco. North winds will
ease somewhat overnight into Thursday, but seas remain hazardous to
small craft through Thursday night. The thermal trough weakens by
Friday and conditions will improve. Relatively light winds and low
seas continue into Saturday, but a weak cold front will move through
in the afternoon. Gusty north winds and steep seas are expected to
return later in the weekend. -Spilde


&&

.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.

&&

$$