722
FXUS66 KMFR 261022
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
322 AM PDT Sun May 26 2024

.DISCUSSION...

Temperatures will warm up today with high pressure building over
the region. We`re currently looking at a 10 degree warm up across
most locations. High temperatures will be warmer than average for
this time of year as highs rise into the mid 80`s in valleys west
of the Cascades. This is really the main theme for Sunday as the
probability of precipitation is essentially zero with mostly
clear skies across the forecast area. Temperatures are also too
cool for a real heat risk. Perhaps the main risk here is cold
water safety during the holiday weekend as people recreating near
cooler rivers are at higher risk of cold water shock. Otherwise,
pretty quiet weather for Sunday

As for Memorial day, not much will change except for a deep upper
level wave moving towards the Pacific Northwest. This will allow
for some deeper synoptic lift and a low threat of thunderstorms
east of the Cascades on Monday evening. Model BUFR soundings show
a deep inverted V sounding with some convective available
potential energy in Lake County. Some of these thunderstorms could
be dry, although it`s not the deepest dry boundary layer we`ve
seen in our forecast area. One can see some of the deterministic
models initiating convection on Monday evening. The probability of
cloud to ground lightning is about 10 to 15 percent with 20 miles
of locations in Lake County. Its worth noting models are picking
up on the threat of thunderstorms in western Siskiyou County as
well around the Trinity Horn.

The axis of the previously mentioned upper level wave will come
onshore sometime around Tuesday afternoon or evening. As a result,
the probability of precipitation will increase over some sections
of the forecast area around Douglas County and the high central
Cascades in Douglas and Klamath counties. It appears a cold front
will accompany this wave and temperatures should trend a few
degrees cooler on Wednesday. We`ll also have to keep an eye out on
winds east of the Cascades on Wednesday evening as there could be
a strong west to east pressure gradient developing on Wednesday
evening.

As for Thursday and Friday, guidance has started to turn drier
compared to the forecast yesterday at this time. It seems
ensembles are catching onto a ridge building in briefly with highs
again testing the mid to upper 80`s west of the Cascades by
Friday. A short wave or perhaps another deeper wave will likely
move into the Pacific Northwest by sometime this upcoming weekend.
This will result in a 10 to 20 percent chance of precipitation
for most of Sunday and perhaps a few showers in the Cascades
Saturday evening.

-Smith

&&

.AVIATION...26/06Z TAFs...Under weak high pressure, VFR weather for
most terminals is expected through the TAF period. Guidance shows
the potential for patchy areas of LIFR/IFR conditions to develop
later tonight along the coast north of Cape Blanco into the Coquille
Basin as well as in the Umpqua Basin. Confidence is low on whether
this would impact terminals at Roseburg and North Bend. Winds may be
easterly enough tonight to keep the lower ceilings away from North
Bend. However, if winds turn southeast enough and there is patchy
fog in the Coquille Basin, these winds could temporarily lower
conditions at North Bend late tonight. Any lower conditions that
develop are expected to improve to VFR for all areas by late
Sunday morning. /BR-y

&&

.MARINE...Updated 200 AM Sunday, May 26, 2024...The Small Craft
Advisory has come down this morning, and no hazards are currently in
effect. Aside from some locally gusty winds nearshore south of Cape
Blanco, high pressure will maintain benign marine conditions
thereafter through Tuesday. Look for increasing north winds and seas
on Wednesday and Thursday. -BR-y/Hermansen

&&

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

CA...None.

PACIFIC COASTAL WATERS...None.

&&

$$