306
FXUS66 KMFR 150601
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1101 PM PDT Mon Jul 14 2025

.Updated AVIATION Discussion...

&&

.AVIATION...15/06Z TAFs...VFR conditions will prevail for most areas
through the TAF period. The marine layer has returned to coastal
locations, resulting in MVFR conditions north of Cape Blanco.
Conditions should gradually lower to LIFR later tonight (11z-13z),
then persist into Tuesday morning. Conditions on Tuesday should be
quite similar to today, with the marine layer retreating to the
marine waters and gusty winds returning to the region in the
afternoon. Isolated showers/thunderstorms are again possible across
northern California Tuesday afternoon. /BR-y

&&

.PREV DISCUSSION... /Issued 848 PM PDT Mon Jul 14 2025/

UPDATE...Isolated to scattered thunderstorms over eastern Modoc
County are moving east of the area this evening. High pressure
will remain centered just offshore with a shortwave trough moving
across the region north of the area tonight and Tuesday. This
will bring slightly less hot temperatures on Tuesday with high
temperatures trending 2 to 5 degrees lower. HeatRisk values are
lower as well. However, temperature remain above normal and there
remains a moderate risk for heat related illness for those
sensitive to heat or without adequate cooling. So, we have kept a
heat advisory in place for valleys west of the Cascades. East of
the Cascades temperatures trend less hot as well. Also on Tuesday,
with the shortwave passing to the north, the National Blend of
Models supports a 10 percent chance for isolated thunderstorms
across southern Klamath, southern Lake, eastern Siskiyou and Modoc
counties. We will continue to monitor this.

Going into Wednesday, expect temperatures to trend slightly
hotter and likely dry weather.

MARINE...Updated 830 PM PDT Monday, July 14, 2025...The thermal
trough pattern will continue through Wednesday. This will maintain
strong north winds and steep to very steep wind-driven seas across
all waters. Gales are expected in the afternoons/evenings mainly
south of Port Orford and beyond 5 nm from shore. Conditions will
begin to improve around mid-week as we transition away from wind-
driven seas. However, steep seas will be found in all areas Tuesday
evening through Thursday morning. -Hermansen/BR-y

PREV DISCUSSION...  /Issued 248 PM PDT Mon Jul 14 2025/

DISCUSSION...It will be another warm afternoon with locations
reaching 95-101 degrees. Taking the warmer morning and the
expected highs into consideration, more locations are under an
elevated risk today. This will impact anyone that does not have
effective cooling and/or adequate hydration. An Extreme Heat
Warning and Heat Advisory is in effect through Tuesday evening for
this heat risk. Details can be found in NPWMFR.

There will be another 10-20% chance of thunderstorms this
afternoon as another shortwave passes through. This will be
concentrated in Siskiyou, Modoc and Lake counties. Tuesday`s
temperatures will be similar to today, but conditions are forecast
to stay dry.

In terms of overnight temperatures, forecast lows will be in the
50s and low 60s for more locations. The northerly flow we`ll have
the next few days will bring low concentrations of near surface
smoke to southern Oregon. Higher concentrations of smoke from the
Butler Fire is forecast in Siskiyou County and for Modoc County
from the Green Fire Tuesday afternoon because of a more westerly
flow there. Smoke higher in the atmosphere will create hazy skies
for more parts of southern Oregon the next few afternoons.

Areas east of the Cascades will likely not be under the risk for the
heat after the current time frame through Tuesday evening, so the
Heat Advisory for east side will be finished then. The main
change in the forecast has been to add a Heat Advisory for west
side valleys on Wednesday due to a 80-95% chance for the Rogue and
Illinois valleys and portions of the Klamath River Valley to see
100 degrees. Either way, precautions need to be made to protect
yourself from the heat. Drink plenty of water, avoid peak heating
between 10 AM and 4 PM, and stay in an air- conditioned room as
much as possible.

Long Term...Thursday through Sunday...Ridging continues through the
rest of the work week with temperatures 5-10 degrees above normal
for this time of year. After, a low starts to develop into western
Canada Thursday into Friday. This will help "cool" temperatures
back to below the 98-101 degree mark for more west side locations.
Looking to still favor drier conditions next weekend and the week
after will have cooler temperatures back to near normal.

FIRE WEATHER...Thunderstorms remain the main fire weather
headline this afternoon and early evening. Read the discussion
above for more details on that. Otherwise, a well defined thermal
trough shown by inverted MSLP and 850mb heights on top of
1000-500mb thickness values spread north into western Oregon.
During this time, light east breezes around 10 to perhaps 15 mph
will cover the Cascades. We continued to keep recoveries moderate
on the western mid slopes of the Cascades and about 10% below
guidance. Overall, fire weather risk is limited through the
forecast period as wind and rh combinations remain below red flag
criteria.

We were interested in wind and rh fire weather conditions Thursday
earlier, although newer data seems to squashed those concerns east
of the Cascades. The one thing to note is ECMWF ENS along with the
GFS is predicting some thunderstorms east of the Cascades Thursday
evening. Again, these storms appears to be on the drier side with a
0.7 PWAT based on the 12Z GFS forecast sounding.

Otherwise, hot and dry weather will persist through this week, but
temperatures do trend a bit lower by the weekend with temperatures
near normal by Sunday.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Heat Advisory until 8 PM PDT Wednesday for ORZ023>026.

CA...Heat Advisory until 8 PM PDT Wednesday for CAZ080-081.

PACIFIC COASTAL WATERS...Gale Warning until 11 PM PDT Tuesday for
     PZZ356-376.

     Small Craft Advisory from 11 PM Tuesday to 5 AM PDT Thursday for
     PZZ350-356-370-376.

&&

$$