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fxus66 kmfr 162151 

Area forecast discussion
National Weather Service Medford or
251 PM PDT Mon Jul 16 2018

Discussion...cumulus buildups are evident over the mountains of
Siskiyou County, and in the Cascades and high terrain east of the
Cascades. There's been many cloud flashes over the past few hours,
and a few cloud to ground strikes in northern Klamath and lake
counties. Expect isolated thunderstorms to continue to develop
over high terrain into this evening. Stearing flow is light, so
expect thunderstorms to be tied to ridges, and unlikely to reach
the valleys. The thunderstorm threat will end tonight, and we'll
transition to a more stable pattern, until Friday or Saturday.

Here at the Rogue Valley Airport, we've already hit 100 and warm
up several more degrees by the end of the day...temperatures
elsewhere are right on track with the forecast, with Roseburg in
the mid 90s and Klamath Falls in the upper 80s. North of the
Umpqua Divide, temperatures will be around 3 degrees lower
tomorrow than today, and continue a slow cooldown into the
weekend. Elsewhere, tomorrow will be similar, if not a few degrees
hotter than today. Along the coast, some fog will likely develop
near Brookings tonight. North of Cape Blanco, a strong marine push
should bring another round of fog and low clouds inland late
tonight into tomorrow morning. Conditions along the coast tomorrow
and Wednesday will be similar to today, except for Brookings. The
NAM indicates that the Chetco effect could bring temperatures into
the 80s for Brookings Wednesday.

Thursday will be fairly uneventful, with temperatures finally out
of the 100s just about everywhere. Friday and Saturday show some
moisture coming into the southeastern portion of the cwa, and with
a decent shortwave, could see some thunderstorms. Not a lot of
confidence in this part of the forecast, as model run to run
consistence in placement of waves hasn't been great. -McAuley


Aviation...for the 16/18z tafs...along the coast...IFR/LIFR
conditions are expected to continue to gradually dissipate this
morning expect the low level stratus to linger a couple miles
offshore in the area north of Cape Blanco this afternoon then return
after 03z this evening and form a similar pattern as was in place
early this morning. Inland, VFR conditions will continue for the taf
period with isolated thunderstorms developing in the late afternoon
and early evening from far southern Siskiyou County northeastward
across the area east of the Cascades with the highest probability
over Northern Lake County. -Dw


Marine...updated 800 am PDT Monday 16 July 2018...a fresh steep
northwest swell will affect the waters this morning. Winds are
expected to be weak near shore, but north winds will trend higher
and reach advisory strength in the outer waters from Cape Blanco and
Port Orford southward. These conditions will persist into Tuesday.
Then, winds and seas will increase on wedensday. Gales and very
steep hazardous seas are possible by Wednesday afternoon south of
Cape Blanco, mainly beyond 10 nm from shore, and small craft
conditions possible elsewhere. These strong gusty winds and steep to
very steep seas may continue through late in the week. -Czs/dw


Fire weather...updated 200 PM PDT Monday 16 July 2018...isolated
showers have developed this afternoon along the Siskiyous and
Cascades, but no lightning has been recorded as of yet. Conversely,
over northern Klamath and lake counties, there have been several
cloud-to-cloud lightning strikes, but only a handful of ground
strikes. Any of these areas could see more isolated lightning through
this afternoon, but most of the activity should remain east of the
Cascades. Thunderstorms and showers should dissipate from west to
east through the evening.

The remainder of the week should remain hot and dry. The warmest
days west of the Cascades will be today or tomorrow, with Tuesday
and Wednesday being the hottest to the east. Temperatures will
gradually, and only slightly, cool through the remainder of the
week. Meanwhile, humidities will be low, with single digit minimum
humidities not uncommon over the next several days, and moderate
recoveries likely in many regions. Some borderline poor recoveries
are possible, especially over ridgelines. Also, winds may become
breezy Tuesday afternoon and evening due to a northwest marine push.

The next chance for lightning arrives this weekend, with some weak
monsoonal moisture pushing into our area Friday afternoon and
evening, and perhaps again on Saturday. Confidence is low, and
models have been pushing it further back and further east with each
passing day. For now, have kept a slight chance in the forecast, but
this could easily change over the next few days. -Bpn


Mfr watches/warnings/advisories...
or...heat advisory until 11 PM PDT this evening for orz023.
Excessive heat warning until 11 PM PDT Tuesday for orz024-026.
Heat advisory until 11 PM PDT Tuesday for orz024-026.

California...excessive heat warning until 11 PM PDT Tuesday for caz080-081.

Pacific coastal waters...Small Craft Advisory for hazardous seas until 11 am PDT

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