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fxus66 keka 222257 

Area forecast discussion
National Weather Service Eureka California
357 PM PDT Thu Aug 22 2019

Synopsis...a gradual warming trend is expected Friday through the
middle of next week, with triple digit heat expected across many
Interior Valley areas expected by Monday. Coastal areas are also
expected to see above normal temperatures, again especially early
next week. Little to no precipitation is expected.


Discussion...after a foggy, drizzly morning along the north
coast, marine stratus has finally cleared and almost all of the
region is experiencing sunny summertime skies. While coastal
temperatures remain very near their typical cool normals, interior
temperatures have climbed well into the 80s and low 90s...which is
also very near normal for mid August. All in all, weather
conditions throughout northern California are fairly typical and
generally benign.

However, gradually building high pressure aloft throughout the
state is expected to drive a gradual warming trend between Friday
and Wednesday, with the peak of the heat expected Monday through
Wednesday. Afternoon Interior Valley temperatures are expected to
climb from the mid to upper 90s Friday through Sunday, to between
100 and 105 degrees Monday through Wednesday...and perhaps locally
higher in a few of the warmer valleys. As a result, the threat of
heat related impacts appears to be increasing, particularly Monday
through Wednesday. The bulk of the heat impacts are likely to be
experienced across Interior Valley locations, but even coastal
areas are likely to observe above normal temperatures by early
next week. Meanwhile, overnight and morning stratus/fog is likely
to continue to develop over the next few days along the coast, but
is expected to gradually reduce in coverage until becoming much
less prevalent early next week.

Between Tuesday and Wednesday, a weak upper level impulse is
expected to move through the region from the southwest. This wave
will likely drive lower surface pressure and light southerly
winds across the waters. While it's possible that this could
eventually result in a surge of very shallow marine stratus from
the south, this will likely lead to above normal coastal
temperatures Tuesday and Wednesday. Meanwhile, while atmospheric
moisture content appears to be meager, a small potential for
isolated and mostly dry thunderstorms will have to be monitored
toward the middle of the week. /Brc


Aviation...the patchy fog which developed this morning has
pretty much cleared out this afternoon, replaced with breezy north
winds with gusts of 20 to 30 kt at the coast. Tonight offshore
flow is expected to develop, potentially keeping the del norte
coast clear. Low clouds are possible around Humboldt Bay once
again while the inland areas remain clear once again. Mkk/tdj


Marine...high pressure has started to build into the area,
driving accelerating northerly winds. These are expected to peak
at gale force this afternoon and tonight in the northern outer
waters. The southern waters and the inner waters may see a few
gale force gusts especially near the CAPES, but they are not
expected to be widespread enough to warrant gale warnings. These
northerlies will generate large and steep seas across the outer

Friday and into the weekend winds and short period seas will
remain moderate to fresh, keeping the steep seas around 7 to 10
feet. Early next week winds will continue to diminish. By mid-week
models are trying to show a trough or upper level low moving into
the area again. The models are fairly confident that winds will
be light, but are struggling with the position of the low and the
direction of the surface winds. Mkk/tdj


Fire weather...a gradual warming trend is expected to unfold
throughout the region between this Friday and Wednesday of next
week, with the peak of the heat expected between Monday and
Wednesday. Afternoon high temperatures are likely to climb from
the mid to upper 90s late in the week and over the weekend, to
near and slightly above 100 degrees Monday through Wednesday. In
addition to the increasing heat, humidity will also decrease, with
very low afternoon minimums expected. Winds are not expected to be
particularly strong on a large scale, and will be driven by
typical daytime onshore and nighttime offshore fluctuations.
Winds may become locally gusty on a smaller scale, most likely in
areas where the terrain favors stronger upslope and upvalley wind

Meanwhile, little to no precipitation is expected for the
foreseeable future. However, while it remains unlikely in
northwest California, a very low chance for isolated dry
thunderstorms near the middle of next week is being monitored.


Eka watches/warnings/advisories...
Northwest California coastal waters...Small Craft Advisory until 5 PM PDT Saturday for pzz450.

Gale Warning until 5 am PDT Friday for pzz470.

Small Craft Advisory until 5 PM PDT Saturday for pzz455.

Small Craft Advisory until 9 PM PDT this evening for pzz475.

Hazardous seas warning from 9 PM this evening to 5 PM PDT Friday
for pzz475.



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