649
FXUS66 KMFR 140546
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1046 PM PDT Fri Jun 13 2025

...Updated AVIATION discussion for 06Z TAFs...

.DISCUSSION (Today through Thursday)...

Overview:

The general theme for the next several days is a low impact forecast
across the area. There will be very isolated chances for a shower or
two this afternoon (no thunder) across Klamath and Lake counties,
but by far and large these chances are very slim (<20%). In fact,
most of the forecast area will remain dry through the next 7 days.
Seasonable temperatures are expected through this stretch with
typical diurnal winds in the afternoon. By late next week, an
approaching trough could change things across the area with breezy
to gusty winds expected and an increase chance for thunderstorms,
especially next weekend. While this is beyond the current 7 day
forecast, its noteworthy enough to talk about now as we go into this
prolonged stretch of dry weather on top of fuels that are already
accelerated in their drying process compared to normal years.

Further Details:

The 500mb flow pattern can be summarized as a mostly westerly to
southwesterly at times through the next several days. This means we
will experience near normal temperatures and dry conditions. Most
afternoons will see typical sustained wind speeds around 5 to 15 mph
with isolated 20 mph speeds in some of the windier sports. That
said, not expecting any wind hazards through at least Wednesday.

For today, mid level water vapor imagery shows dry air moving
through the area. This dry air is essentially rounding the base of a
weak trough passing over the area within this southwesterly flow
aloft. Showers are going to really struggle once that dry air moves
into the area. Day cloud phase distinction from GOES satellite does
indicate towering cumulus, but no ice glaciation is occuring as
vertical growth is struggle under this regime, but we are seeing
some returns on radar from what is likely mixed with some virga. As
the upper level trough pushes farther east, the dry air will only
make matters harder for vertical growth and updrafts. That said,
will maintain 2-3 hours of possible showers across northern Klamath
and Lake counties. Not expecting these to have enough time to
develop into thunderstorms within our forecast area before the dry
air moves in.

Temperatures will be very seasonable to slightly below (today) to
even slightly above normal on some days. In other words, not seeing
any heat risks through early next week. In fact, there may be some
isolated spots that dip down near freezing tonight for areas in both
far northern Klamath and Lake counties for an hour to maybe two
hours before sunrise.

The more notable item may come after this forecast period as a
deepening trough could develop over the Pacific and impact the PacNW
late next week into next weekend. The concern here is that our fuels
have seen an accelerated period of curing with fuels more
representative of July. This means any lightning from thunderstorms
could become a problem with fire starts. This comes at a time when
wind speeds will start to pick up in association with the trough and
could be on the breezy side (15-30mph). This will be couple with RH
values in the teens to low 20 percent range in the afternoon. Stay
tuned as this is beyond the current 7 day forecast, but this trough
could be an impactful end to next week.

-Guerrero

&&

.AVIATION...14/06Z TAFs...Marine stratus remains over the Oregon
coast north of Cape Blanco and in the Umpqua Valley tonight.
Ceilings are staying at VFR so far. Guidance suggests a period of
MVFR or IFR ceilings may be possible at North Bend, but the short
duration and high uncertainty is keeping those conditions out of the
forecast. There`s more confidence in these ceilings clearing on
Saturday morning and gusty winds building along the Oregon coast in
the afternoon.

Other inland areas look to remain at VFR levels with only normal
diurnal wind changes in the forecast. -TAD

&&

.MARINE...Updated 200 PM Friday, June 13, 2025...High pressure
offshore and low pressure inland are expected to persist into the
weekend. Seas will remain dominated by a mix of northerly wind wave
and fresh swell through the weekend with conditions hazardous to
small craft. The strongest winds and steepest seas are expected
south of Gold Beach and out 30 nm from shore, into this evening when
very steep seas are forecast. A weak front early on Monday is likely
to disrupt the pattern and bring improved conditions that could last
into next Wednesday.

-Petrucelli

&&

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

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

Hazardous Seas Warning until 2 AM PDT Saturday for PZZ356-376.

&&

$$