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Area forecast discussion 
National Weather Service Eureka California
307 PM PDT Tuesday Jul 28 2015

Synopsis...strong ridging aloft and offshore surface flow will
continue this week which will prolong dry weather and generate hot
temperatures for inland areas. Coastal areas will remain warmer than
normal with decreased cloud cover through the week.

&&

Discussion...high pressure continues to build over the West Coast
today in the wake of an upper trough that has lifted out of the
area. Stable weather conditions and above normal temperatures will
last through much of the week across northwest California. Moderate
offshore flow over northwest California has led to a drying and warming
trend. Temperatures will likely be 5 to 10 degrees above normal
across the interior with coastal locations seeing warmer than normal
temperatures as well with decreased cloud cover and downsloping
winds off of the coastal ridges. The temperature had already reached
77 f at the Eureka weather forecast office on Woodley Island as of 1pm...breaking the
daily record of 69 last set in 2000...as well as the monthly
record of 76 last set on July 3rd back in 1992. Many other
locations along the coast were in the 70s to near 80. Record high
temperatures for coastal locations will be possible again on
Wednesday with temperatures forecast anywhere from the lower to
upper 70s in most locations. Kept temperatures slightly lower than
consensus models due to the weaker offshore flow expected
Wednesday. Some inland valley locations could also approach 110 f
on Wednesday as heights continue to build over the area.

Late in the week...models show a broad upper trough developing
over the eastern Pacific. This will cause temperatures to decrease
to near or slightly above normal for this time of year across the
interior. The trough will meander around west of 130w through the
weekend into early next week. This trough offshore combined with a
strong ridge over the desert SW will place northwest California under a
southerly flow regime. Model consensus remains good in the large
scale features...but continues to be inconsistent in the finer
details. Increasing middle level moisture along with modest
instability and embedded impulses in the southerly flow will bring
the possibility of isolated thunderstorms to the interior this
weekend into early next week. Stp

&&

Aviation...VFR conditions and moderate to moderate and gusty winds
will continue at kcec and kacv through the early evening. VFR to
MVFR conditions and light winds to calm conditions will occur at
kcec and kacv overnight. VFR conditions and light winds to calm
conditions will continue at kuki through Wednesday.

&&

Marine...an offshore high pressure system interacting with an
inland thermal low pressure system will continue producing elevated
northerly winds and large steep seas across the outer waters through
this evening. The offshore high pressure system will shift westward
Wednesday and Thursday weakening the pressure gradient across the
waters. Therefore the winds and seas will diminish the next few days
as the pressure gradient relaxes. Seas will gradually subside
Wednesday through the end of this week

&&

Fire weather...strong ridging aloft will continue this week
prolonging dry weather and generating high temperatures close to 10
degrees above normal for inland areas. Poor relative humidity recoveries were found
across the upper slopes and ridges overnight with moderate offshore
winds. While winds have decreased some today...E-NE winds are
expected to increase again tonight...highest across the northern
areas. This will lead to poor relative humidity recoveries and critical fire weather
conditions...highest across fire zones 203 and 204. As such...have
upgraded the Fire Weather Watch to a red flag warning from late
tonight through Wednesday morning for areas above 3500 feet in 203
and 204. Although the winds look slightly weaker tonight into
Wednesday...relative humidity recoveries will be even worse than last night.

Fuels will continue to dry through middle-week with poor nighttime
recoveries persisting. However...winds are expected to diminish
Wednesday and become more terrain-driven for the remainder of the
week. Stp

&&

Eka watches/warnings/advisories...
California...
red flag warning from 11 PM this evening to 11 am PDT Wednesday
for caz003.

Northwest California coastal waters...
Small Craft Advisory until 9 PM PDT this evening for pzz450.

Gale Warning until 9 PM PDT this evening for pzz470.

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

&&

$$

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