FXUS66 KMFR 291044
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
344 AM PDT Mon Jul 29 2024

.DISCUSSION...Satellite imagery is showing marine stratus across
much of the coast with some smoke from nearby wildfires. Most
areas elsewhere remain cloud free but there is some additional
cloud cover offshore that will push onshore Coos and Douglas
County later this morning. Southern Oregon and northern California
remain under the influence of a broad trough affecting most of
the Pacific Northwest and Canada, and the aforementioned cloud
cover is part of a frontal boundary that will move inland today.

This system may produce a few showers in northwest Douglas and
northern Coos County, but most areas will remain dry. Expect non-
wetting rainfall for portions of the marine waters and maybe for
the Douglas County Coast. A few showers may occur for northern
Lake and Klamath Counties on Monday afternoon with the front, but
expect most of our precipitation to be to our north.

From Tuesday onward, we enter back into a ridge pattern with
warmer drier and breezy conditions through much of the week. By
the end of the week, the forecast has afternoon temperatures
reaching above the century mark once again for many west side
valleys with the east side and Umpqua Valley reaching into the mid
90s. The coast will be a little warmer as well with temperatures
reaching into the 70s. We will need to monitor the forecast for
any heat or fire weather related products in the extended. -Schaaf

&&

.AVIATION...29/12Z TAFS...Marine stratus/fog and patchy drizzle will
impact all areas along the coast and over the coastal waters this
morning. Expect widespread IFR/LIFR ceilings and visibility for all
coastal sites, including at North Bend. Patchy MVFR ceilings could
develop in the Umpqua Basin around sunrise, but overall, VFR should
prevail there. VFR is expected elsewhere inland through this
evening, though some mid and high level clouds associated with a
weak front will arrive and push through later this morning through
this evening. The lower ceilings along the coast this morning should
lift to at least MVFR, but the front could bring some light
rain/drizzle again NW of the Umpqua Divide and along the coast into
this evening. A deep marine push is expected west of the Cascades
tonight with some "spillover" possible into the Rogue/Illinois
valleys. Overall, ceilings will range from MVFR to VFR inland,
between 2000-5000 ft, but probably IFR/LIFR again along the coast.

Winds this afternoon/evening will be more westerly with the densest
wildfire smoke staying away from the TAF locations. Some smaller
airports in northern Lake or Klamath Counties could see visibilities
as low as 3SM. -Spilde


&&

.MARINE...Updated 200 AM Monday, July 29, 2024...A weak front
will bring mostly light south to southwest winds and a chance of
light rain showers or drizzle today. The front moves inland tonight
with relatively calm conditions persisting into Tuesday. North winds
return Wednesday and Thursday and seas could become steep again,
especially beyond 10 NM from shore. Winds and seas lower briefly on
Friday. Then, a stronger thermal trough could set up over the
weekend. This is most likely on Sunday with the net result being
stronger north winds and increasing wave steepness, highest south of
Cape Blanco, lasting into early next week. -Spilde

&&

.FIRE WEATHER...Issued 300 AM Monday July 29, 2024...A mostly
dry cold front will pass through the area late Monday into
Tuesday, and some drizzle or very light rain is possible along the
coast and into the Umpqua Basin. The timing of the front will
lead to a very delicately balanced situation. While winds are
expected to increase as the front approaches, humidities are
expected to also rise, keeping most of the area well under
critical thresholds. East of the Cascades, particularly in zone
625, humidities will be slower to rise, but conditions should
still remain below critical thresholds, although it will be very
close. No products are expected for this, however.

After the front passes, upper level ridging and the thermal trough
will quickly return to the area for the remainder of the week, with
temperatures once again rising to well above normal while humidities
and overnight recoveries worsen. Typically a period of instability
and thunderstorms tends to follow these periods of heat, and this
looks to be no exception. Confidence on any detail of timing and
location is much too low at this time frame, but we will continue to
monitor the potential for lightning next weekend. -BPN


&&

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

CA...None.

PACIFIC COASTAL WATERS...None.

&&

$$