Grenada, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

318
FXUS66 KMFR 200954
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
254 AM PDT Fri Jun 20 2025

.DISCUSSION...An upper low is located off the coast of British
Columbia early this morning and will shift southward and inland into
the Washington and Oregon today. This will bring showers, much
cooler temperatures, and breezy to gusty afternoon/evening winds.

* Much cooler temperatures expected today with highs in the 50s
  and 60s today.
* Showers will increase along the coast and into the Umpqua Basin
  this morning, then across most the area this afternoon and
  evening.
* Isolated thunderstorms are possible from the Southern Oregon
  Cascades west and across northern Klamath County today.
* Breezy to gusty winds west winds this afternoon and evening,
  strongest from the Cascades east and over Northern California.
* Showery, cool and breezy to gusty conditions continue Saturday.

Models continue to support a slight chance (15-20%) for
thunderstorms from the coast to the southern Oregon Cascades and
across northern Klamath County today. There is also a 5-10%
chance for thunderstorms across other area east of the Cascades
and into Northern California.

Precipitation amounts in showers will vary with highest amounts
expected along the coast, into the coastal mountains, Umpqua Basin
and Southern Oregon Cascades. These areas are forecast to see
around 0.25 to 0.75 inches of precipitation. Across Jackson and
Josephine Counties, amounts of 0.10 to 0.50 inches are expected.
East ofthe Cascades and across northern California, generally
lighter precipitation is expected with around 0.03 to 0.20 inches
in showers.

Cold air advection with this low will result in snow levels
lowering to around 5500 to 6000 feet with snow showers possible
over higher mountains, such as in the Crater Lake area. The
current forecast supports light snow of 2 to 5 inches in the
Crater Lake area. Afternoon high temperatures will be below
normal across the area with highs in the 50s and 60s for valleys
east of the Cascades and in the 60s for valleys west of the
Cascades. Additionally, gusty west winds are likely this
afternoon/evening with the strongest winds east of the Cascades
and across Northern California, with gusts to around 25 to 30 mph.

With the low remaining in place on Saturday, expect a second day
of cooler temperatures, showers and breezy to gusty winds. Chances
for showers will be highest (40-90%)  from the Southern Oregon
Cascades west and over northern Klamath and northern Lake
counties, with lower chances (10-30%) elsewhere in southern
Klamath, southern Lake and northern California.

This low will  shift east of the area Saturday night into Sunday,
with an upper trough remaining over the region. Chances for
showers will diminish on Sunday and models and guidance indicate
temperatures will trend warmer, but still remain slightly below
seasonal normals.



&&

.AVIATION...20/06Z TAFs...Tonight, VFR will prevail, but MVFR
ceilings have been in and out at North Bend. Expect MVFR to become
more widespread at the coast overnight, especially north of Cape
Blanco with showers developing around/after 09Z. Expect widespread
showers for areas west of the Cascades during Friday, where there
can also be isolated thunderstorms. These, however, are most likely
along the coast and into the Umpqua Friday afternoon. Expect some
gusty winds again Friday afternoon, especially east of the Cascades
with peak gusts of 20-30kt. Thunder risk wanes Friday evening, but
showers are likely to continue with areas of MVFR and terrain
obscuration Friday night into Saturday. -Spilde

&&

.MARINE...Updated 200 AM Friday, June 20, 2025...Winds and seas
will remain relatively light on Friday. Low pressure will bring
unseasonably cool air, numerous showers and also isolated
thunderstorms, especially north of Cape Blanco, Friday afternoon
and evening. Expect west winds and fresh swell dominated seas.
Cool, showery, unsettled weather continues Friday night into Saturday.
Seas will build slightly and may become steep in the outer waters
late Friday night and Saturday. A thermal trough returns Sunday
through Monday with north winds and steep seas likely south of
Cape Blanco.


&&

.PREV LONG TERM DISCUSSION... /Issued 316 PM PDT Thu Jun 19 2025/

A warming and drying trend begins Sunday with highs near normal on
Sunday and expected to be consistently several degrees above
normal for the remainder of next week. Also of note, the SREF is
showing weak instability for the Cascades from Crater Lake
northward on Sunday with a 10% probability of late day
thunderstorms. This is supported by the 12Z NAM, but the 12Z GFS
indicates a dry air mass. We will expect a consensus to form as
the time draws nearer. More broadly, but beyond the shorter term
models, the 12Z GFS does indicate weak instability for the
southern Oregon Cascades into south central Oregon and northern
California. So, the probability of thunderstorms has been nudged
up to 10% for that area on Monday afternoon and evening.
Otherwise, next week looks to be generally stable and very warm
inland while night and morning low clouds will be prevalent at the
coast with typically cool temperatures.

&&

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

CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 2 AM PDT early
     this morning for PZZ356-376.

&&

$$