067
FXUS66 KMFR 191013
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
313 AM PDT Wed Jun 19 2024

.DISCUSSION...A warming trend continues today, with everywhere that
isn`t Cape Blanco expected to be 5 to 10 degrees warmer than
Tuesday. The rest of the Oregon coast will approach 70 degrees and
west side valleys will reach the mid to high 80s. Areas east of the
Cascades will mostly be in the mid to high 70s. Daytime highs will
continue to rise through the rest of the week and into the weekend.
West side valleys will be in the low to mid 90s on Friday, with
similar temperatures spreading east of the Cascades on Saturday.
Probabilistic NBM guidance suggests a 50% chance of triple digits in
the Shasta and Scott valleys on Saturday, with a 25% chance in
Medford. Nighttime lows will be comfortably away from freezing by
the end of the week.

Outside of the warming trend, little activity is expected through
Saturday evening. A weak shortwave will pass over on Thursday,
bringing enough instability for a wave of cumulus to move eastward
through the day as well as very slight thunderstorm chances on
Thursday evening. The "highest" chances are currently over eastern
Douglas and northern Klamath counties, but at 5-8% these chances are
hardly remarkable. Lesser chances continue down across the rest of
Klamath County and over Siskiyou County. Activity is hardly
expected, but the chance is worth mentioning. Anything that does
develop would most likely be an isolated pulse thunderstorm.

Guidance continues to suggest that heat warning products are not
necessary. Widespread areas of moderate heat are expected, but
nighttime cooling will mitigate the risk of overall hazardous heat.
However, individual heat tolerance needs to be considered. Anyone
who is not acclimated  to these temperatures or is sensitive to warm
weather will want to be careful during any outdoor activities this
week.

A weak front attached to a low pressure system in the Gulf of Alaska
will help to slightly cool temperatures on Sunday and into the
beginning of next week. Generally, daytime highs are forecast to be
in the mid 60s to low 70s along the coast and in the mid to high 80s
inland. Afternoon breezes will increase as the pattern around the
low pressure system will put the area under the leading edge of an
upper trough, but currently nothing approaches Advisory levels.
Previous slight precipitation chances over the Oregon coast are
currently absent from deterministic outcomes, and ensemble
meteograms show that only traces of rainfall are possible over North
Bend on Sunday and Monday. This is more likely part of an early
morning marine push than any actual rainfall. -TAD

&&

.AVIATION 19/12Z TAFs...For inland areas, VFR ceilings and
visibilities are anticipated through the TAF period as high pressure
builds. For the coast and coastal waters, IFR/LIFR stratus will
persist mainly beyond 10 nm from shore, but patches of these lower
ceilings are likely to build into the coast north of Cape Blanco
overnight into the early morning, around 16Z. This includes North
Bend(KOTH). IFR ceilings look to return to the coast north of Cape
Blanco this evening, around 04Z, and spread into the Coquille and
lower Umpqua valleys overnight into early Thursday morning.
-DW

&&

.MARINE...Updated 230 AM Wednesday, June 19, 2024...High pressure
offshore and a thermal trough along/near the coast will remain in
place at least through the weekend, and likely through Monday. This
will result in persistent northerly winds and wind-driven seas
through this period. Conditions will be worst south of Cape Blanco
where winds and steep seas hazardous to small craft will persist.

The thermal trough will strengthen further this afternoon into
Friday evening, and this may bring very steep seas and/or northerly
gales to the waters south of Cape Blanco Thursday afternoon into
Friday evening. The latest model solutions keep winds just under
gales at this time. With this uncertainty, it is recommended
mariners to stay tuned to updates as we move through the week.

-Sargeant/DW

&&

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

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT Friday
     for PZZ356-376.

Small Craft Advisory until 5 AM PDT early this morning for
     PZZ350-370.

&&

$$

TAD/TAD/DW