757
FXUS66 KMFR 121736 AAA
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1036 AM PDT Fri Jul 12 2024

Updated Aviation Discussion.

.DISCUSSION...Near zonal flow remains in place today as high
pressure remains centered to the southeast over the four corners
region. With this pattern expect continued hot and dry conditions
across inland areas. Hot daytime temperatures are expected today,
similar or 1-2 degrees warmer than yesterday. Then temperatures
will trend slightly higher on Saturday, followed by slight
cooling Sunday. With the continued heat excessive heat warnings
and heat advisories remain in place. Please see the NPWMFR for
details.

Additionally, a weak but dry upper level disturbance will move
inland today. As mid level winds increase with this disturbance,
expect gusty northwest surface winds this afternoon into this
evening. This combined with hot and dry weather will result in
elevated fire weather conditions for areas east of the Cascades.
Please see the fire weather discussion and Red Flag Warning
(RFWMFR) for more details.

Heading into the weekend, the concern shifts to the potential of
thunderstorms. Additionally hot daytime temperatures will continue
across most inland areas through at least Saturday. Models show a
weak low off the coast of California Saturday and Sunday with mid
level, monsoonal moisture moving up into northern California and
into areas east of the Southern Oregon Cascades. Models indicate
that this combined with daytime instability, will support a 10-20%
chance for thunderstorms east of the Cascades on Saturday and
10-25% chance for thunderstorms on Sunday for northern California
and portions of the Southern Oregon Cascades and eastward.
Overall, mid level moisture is lower on Saturday, so any storms
that develop may be on the dry side with elevated storm bases and
gusty outflow winds. Then mid level moisture increases on Sunday,
resulting in an increased chance for thunderstorms. However,
storms will likely trend wetter compared to Saturday. Any
thunderstorms that develop will bring elevated risk for fire
starts. A fire weather watch is in effect through the weekend for
this potential.

The weak low will become positioned off the coast of southern
Oregon on Monday then weaken and move inland on Tuesday. Models
continue to show dry weather across the area during this period
with very low chances for thunderstorms from the Cascades east.
Further east and northeast, there are high chances for
thunderstorms or showers. Breezy afternoon/evening winds are also
possible across inland areas late Monday into Tuesday. Mid to
late week, we remain under the influence of a high to the
southeast and east with a weak, but dry, front approaching late
Wednesday then moving inland around Thursday.



&&

.AVIATION...12/18Z TAFS...Along the coast and just offshore. Current
satellite image shows marine stratus along the coast and offshore
from about Cape Blanco north and Pistol River south. The marine
stratus should burn off south of Pistol River between 20-21z and
lasting into this evening, before returning tonight. Meanwhile the
marine stratus will peel back just off the coast this afternoon,
then return between 0-1z this evening, and between 1-2z at North
Bend with IFR and local LIFR ceilings. Moderate to strong winds are
likely into this evening from Gold Bach north, before gradually
diminishing later this evening.

Inland, VFR conditions will continue through the TAF period, except
for MVFR visibility between 4-5 miles in the vicinity of the Shelly
Fire. Visibility could briefly lower to 5 miles near the Salt Creek
Fire, but the prevailing visibility should remain 6 miles or
greater. -Petrucelli

&&

.MARINE...Updated 300 AM Thursday, July 11, 2024...Northerly winds
35 to 38 knots have been observed in the outer waters this evening
by a passing satellite. These northerly gales will likely develop
again later this afternoon and evening with the strongest winds
around 10 to 20 nm away from shore from Gold Beach. Steep wind
driven seas up to 14 feet will persist in roughly the same area and
locations farther south.  Conditions improve slightly Saturday and
Sunday, although still remain hazardous to smaller crafts.

By next week starting around Tuesday, we`ll see significantly lower
seas around 4 to 6 feet across all the waters.

-Smith

&&

.FIRE WEATHER...Issued 300 AM Friday July 12, 2024...

...Critical conditions with gusty winds and low humidities this
afternoon/evening east of the Cascades...

...Hot and dry with a potential for thunderstorms expected Saturday
and Sunday afternoons/evenings...

Hot, breezy, low humidities, and unstable afternoon conditions
will persist through this weekend. Additionally, a weak upper
level disturbance will result in increased winds this
afternoon/evening winds for areas east of the Cascades. This
combined with very low humidities will bring critical conditions
to these areas. Then the concern shifts to the potential for
thunderstorms Saturday into Sunday during a period of continued
hot and dry weather.

Today, models continue to support gusty winds (15-20 kt) across
areas east of the Cascades. This combined with very low humidities
(down to single digits) will result in critical fire weather
concerns. A red flag warning (RFWMFR) is in place today for these
conditions, in fire weather zones 624, 625, 284 and 285. Breezy
west to northwest winds are expected west of the Cascades with a
potential for brief or local critical conditions, especially in
portions of central and western Siskiyou County.

Hot and very dry weather continues into the weekend. Temperatures
will trend slightly higher on Saturday, then slightly less hot on
Sunday. Additionally, we have a chance for thunderstorms (10-20%)
this weekend, for areas east of the Cascades on Saturday and from
the Cascades east and Siskiyous south on Sunday. Fire weather
watches are in place for areas east of the Cascades. Current
models also support a chance (10-15%) for thunderstorms from the
Siskiyous south in northern California. So, we will also need to
monitor the potential for thunderstorms from the Siskiyous south
on Sunday.

-CC


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Heat Advisory until 9 PM PDT Saturday for ORZ024-026-029>031.

     Red Flag Warning from 2 PM this afternoon to 8 PM PDT this
     evening for ORZ624-625.

     Fire Weather Watch from Saturday afternoon through Sunday
     evening for ORZ624-625.

CA...Excessive Heat Warning until 9 PM PDT Saturday for CAZ080>082.

     Heat Advisory until 9 PM PDT Saturday for CAZ083>085.

     Red Flag Warning from 2 PM this afternoon to 8 PM PDT this
     evening for CAZ284-285.

     Fire Weather Watch from Saturday afternoon through Sunday
     evening for CAZ284-285.

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

     Gale Warning until 8 AM PDT Saturday for PZZ356-376.

     Small Craft Advisory from 8 AM Saturday to 5 PM PDT Sunday for
     PZZ376.

&&

$$

CC