Helm, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

975
FXUS66 KMFR 142312
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
Issued by National Weather Service Portland OR
412 PM PDT Wed May 14 2025

.UPDATE...Updated Aviation Discussion.




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.AVIATION...Expect mostly VFR tonight through Thursday afternoon,
with some areas MVFR ceilings developing late this evening
through early Thursday morning along the coast north of Cape
Blanco and into the Coquille Valley. Areas of higher mountain
obscurations are expected across the area this afternoon and this
evening and again tonight/Thursday morning across Coos and
Douglas Counties and into the South-Central Oregon Cascades.


&&

.PREV DISCUSSION... /Issued Issued by National Weather Service Portland OR/

DISCUSSION...Satellite images shows the higher cloud deck
diminishing, with ample mid and low level clouds mainly along and
west of the Cascades. Cloud cover should gradually diminish later
this afternoon into this evening. Radar is not showing any
returns and with no areas reporting precipitation. Thus, it`s
shaping up to be a dry day for the rest of the afternoon.

Dry weather is likely tonight into Thursday morning as weak upper
ridging builds in. Cloud cover will continue to dissipate this
evening and tonight with mostly clear skies. The exception will be
along and north of the Umpqua Divide and possibly the north
facing slopes of the Siskiyous and west facing slopes of the
Cascades where cloud cover could get banked up.

Any cloud cover in the above mentioned areas will dissipate later
in the morning, with brief clearing before clouds move in from
the northwest ahead of the next weak disturbance. This disturbance
could bring a few showers along the north coast and northwest
Douglas County Thursday afternoon.

The weak shortwave will move north of the area tonight, with the
best chance for precipitation remaining over the northern part of
our forecast area. This could include portions of Douglas County,
northern Klamath and Lake County. Even then showers will be mainly
isolated with very light precip amounts.

Dry weather returns Friday with milder temperatures in the
afternoon.

There`s good agreement another, but stronger upper trough will
move in from the northwest Friday night and Saturday resulting in
cooler temperatures with showers increasing during the day and
possibly becoming more frequent in the afternoon due to a daytime
heating resulting in increasing instability. Isolated
thunderstorms are also possible Saturday afternoon, but the
general consensus is instability will be greatest east of the
Cascades, thus have a slight chance of storms in this area.

The upper trough will exit out of the area Saturday night, but
there`s some question as to the location of another weak upper
trough to follow Sunday. The operational GFS slides the upper
trough over our area while the ECMWF has it farther north which
would favor a drier solution. The respective individual ensemble
members pretty much follow the operational solutions.
Additionally, the majority of the clusters also lean towards a
dry solution. The one commonality is they all show drying Sunday
afternoon. Therefore we`ll keep a slight chance of showers for the
northern Cascades, and portions of the Coastal counties Sunday
morning with dry conditions in the afternoon.

The general consensus shows upper ridging building in Sunday night
through Monday. The operational ECMWF suggest the ridging will
flatten out as a shortwave moves in from the west, and shows some
evidence of light precipitation for the northwest part of the
area. However the majority of the individual ECMWF ensemble
members and clusters favor stronger upper ridging, thus we`ll keep
the forecast dry for the start of next week.

In fact most, if not all of next week could end up dry with
sufficient evidence supporting stronger ridging to at least keep
the storm track north of our forecast area. -Petrucelli

MARINE...Updated 200 PM Thursday, May 14, 2025...A thermal trough
is developing along the coast and gusty north winds are returning,
highest south of Cape Blanco this afternoon. These winds will
persist through Thursday evening. Steep short period are
developing, with conditions hazardous to small craft, especially
from Gold Beach southward. Wave conditions improve a bit Friday,
but low pressure will bring showers Friday night into Saturday
followed by increasing west-northwest swell this weekend.
-Spilde/Hermansen

&&

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

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Friday
     for PZZ356-376.

&&

$$