609
FXUS66 KMFR 101144
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
444 AM PDT Thu Jul 10 2025

...New Aviation Section...


.AVIATION (12Z TAFs)...

IFR/LIFR conditions are evident along/near the coast thanks to a
marine layer of stratus and some instances of reduced
visibilities. This will be the case for most of this TAF cycle
minus some afternoon relief in ceilings/visibilities before
another marine layer pushes in tonight. Otherwise, mostly VFR
conditions are expected for inland sites, but Roseburg will
experience MVFR conditions through the morning hours for ceilings.

-Guerrero

&&

.PREV DISCUSSION... /Issued 320 AM PDT Thu Jul 10 2025/

DISCUSSION (Today through Wednesday)...

Overview:

Forecast now shifts towards one main impact which will be the
heat starting this weekend and continuing into next week. Some
areas (e.g. westside valleys) could see several days in a row of
triple digit temperatures (or close to it). An Extreme Heat Watch
is in effect from Saturday through Monday for some westside areas,
but this could easily be extended in time as Tuesday could be the
overall warmest day. Through the net several days we are not
expecting any precipitation. In fact, there are no signs of any
reasonable chances for precipitation through at least the end of
next week. Further curing of fuels will be a concern through this
stretch of hot weather.

Further Details:

The Pacific Northwest will be under a mostly zonal flow pattern at
500mb through the next several days with occasional disruptions to
this westerly flow. The overall state of the atmosphere will be
noted by 1000-500mb thickness levels hovering around 580-585dam.
This will ultimately lead to several warm days with Tuesday being
the peak of the heat. For perspective, the probability for Medford
to see at least 100 degrees Saturday through Wednesday is roughly 60
to 95 percent. Tuesday is the peak in heat with the probability for
Medford to see at least 100 degrees at about 95 percent.

This stretch of weather will also be noted by poor to moderate
overnight RH recoveries thanks if part to the warm overnight low
temperatures. This means fuels will likely head towards/near the
96th percentile by the time this stretch of warm weather is over. At
this time, the overall driest day (lowest afternoon RH) appears to be
Tuesday with many areas dropping into the teens through the
afternoon hours. However, the stretch from Sat-Wed will experience
very dry afternoon RH values overall for many areas. Each of these
afternoons will be accompanied by some areas experiencing breezy
sustained wind speeds around 15 to 25 mph with occasional gusts
around 25 to 30 mph. At this time, not seeing an overlap of
critical wind speeds coupled with critical RH values that would
warrant any Red Flag Warnings at this time; however, elevated
fire weather conditions are likely through this stretch of warm
weather.

-Guerrero

AVIATION (06Z TAFs)...

VFR prevails inland. However, smoke due to active fire behavior
on area wildfires during Wednesday afternoon could result in
reduced visibility in the immediate vicinity of the fires, but
especially around the Elk fire south of Beatty, the Marble Complex
in Siskiyou County and the Deming/Neil Creek fires near and west
of Ashland.

Marine stratus exists along the coast with IFR/LIFR. These
conditions will last into Thursday morning in most areas, including
North Bend, before eroding back to the coast or offshore Thursday
afternoon. Models show MVFR ceilings could also develop around
Roseburg for a few hours Thursday morning before dissipating.

-Spilde

MARINE...Updated 300 AM PDT Thursday, July 10, 2025...A thermal
trough will intensify today, bringing gusty north wind-driven seas
across area waters. By this evening, steep seas will expand north
of Cape Blanco with gale conditions to the south. The strongest
winds look to be south of Port Orford. The peak in strength for
the thermal trough over near term looks to be Friday where the
probability of wind gusts 45 mph or greater is around 50 to 75
percent south of Port Orford. This pattern could continue through
the weekend and into early next week as the thermal trough looks
to maintain in strength for the next several days bringing at
least steep seas across area waters.

-Guerrero

FIRE WEATHER...Updated 200 PM PDT Wednesday, July 9, 2025...
After warm, slightly above normal temperatures today and
Thursday, heat will then return to the region this weekend into
early next week. Meanwhile, expect fairly typical late-day
summertime breezes, but also dry afternoon humidity. Also, a
general easterly/offshore flow is forecast to develop over the
coastal mountains and Siskiyou mountains each night, which may
result in moderate to locally poor RH recoveries, especially over
the ridgetops. This will not be a strong east wind pattern, but
will be sustained for several days.

-BPN

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Extreme Heat Watch from Saturday afternoon through Monday
     evening for ORZ024-026.

CA...Extreme Heat Watch from Saturday afternoon through Monday
     evening for CAZ080-081.

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

     Gale Warning from 5 PM this afternoon to 11 PM PDT Friday for
     PZZ356-376.

&&

$$