Area Forecast Discussion
Issued by NWS Eureka, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
FXUS66 KEKA 202101

National Weather Service Eureka CA
201 PM PDT Fri Apr 20 2018

.SYNOPSIS...Above normal high temperatures are expected for the
interior this weekend. Occasional stratus and breezy afternoon
winds will keep temperatures near normal for coastal areas. Mainly
dry weather is expected to continue through most of next week.


.DISCUSSION...Stratus has been slowing increasing along the
shoreline today. The stratus will expand over the coastal plain
this evening and spread into the coastal river valleys through the
night. Daytime heating and mixing on Saturday will scour out the
low clouds and expect bright sunshine with brisk northerly winds
for the afternoon hours.

Inland high temperatures were several degrees warmer today.
The warming trend will continue on Saturday, with highs
expected to reach the mid 70s to lower 80s. A shortwave trough
will move over the area on Sunday and interior temperatures will
either level off or cool slighlty. Breezy northerlies on Sunday
may result in greater cooling for the coastal river valleys.

Patchy frost will be possible late tonight and again late
Saturday night in Trinity county. The coverage will be limited to
the most wind protected valleys. For now will hold off on
hoisting a frost advisory. The duration of temperatures at or
below 36F should mitigate the severity of the frost which has
occurred for the last couple of nights.

High pressure will continue to dominate on Monday and Tuesday.
Continued dry conditions with above normal high temperatures will
persist for inland areas. The coast may see highs in the 60s on
Monday with mainly clear skies due to an offshore flow. On Tuesday,
the ridge axis will buckle and move east increasing the potential
for longer duration coastal stratus.

Wednesday through Friday, an upper level trough/low will approach
130W south of 35N on Wednesday and then meander about offshore
during the latter portion of the week. The models were in general
agreement, but continued to diverge with minor precip generation.
The consensus is for cooling in the interior and an increase in
coastal stratus mid to late next week. There does appear to be a
slight chance for showers and isolated convection, especially for
the interior mountains with daytime heating. The potential for
showers may increase on Friday as the offshore low starts to
eject northeastward toward NW California. Confidence in this
scenario is not high due to the tendency for the models to be too
fast with ejecting cut-off lows. Overall, it is not a pattern that
would result in prolonged wet weather for NW California. There is
a potential for some showers and convection, however.


.AVIATION...Generally benign weather continued across the region
today under a dome of high pressure. A blanket of marine clouds
hovered over the Eel Delta this morning with stratus shreds
lurking along sections of the Redwood Coast. This morning`s TAF
added TEMPO after 1 PM at ACV for stratus. Shortly after 1 PM, ACV
reported BKN008. The concern at ACV and CEC will be the
reintroduction of marine stratus late night and morning. At this
time, mixed confidence if stratus will be widespread in the
morning. A front, associated with an upper level trough, will
brush the northern periphery of Del Norte. The tail end will
remain mostly dry, therefore keeping rain chances north of the
region. However, increasing mid-high clouds associated with this
system will Trek across North Coast. /TA


.MARINE...Northerly winds will increase over the waters tomorrow
with gales expected over the outer waters as a thermal trough
strengthens over the mainland. Near shore, strong winds are forecast
with the possibility of some gale force gusts near the 10 nm
line. In addition to these winds, large and steep wind waves will
build in response. The combination of the wind driven waves and a
NW swell will lead to 12 to 14 ft seas beyond 10nm and 8 to 11 ft
seas within 10nm. The Gale Watch remains in effect for the outer
waters and Small Craft Advisories have been hoisted for the inner
waters. /SEC/KR


Small Craft Advisory from 11 AM Saturday to 9 PM PDT Sunday for
PZZ450. Gale Watch from Saturday afternoon through Sunday
evening for PZZ470-475. Small Craft Advisory from 8 AM Saturday
to 9 PM PDT Sunday for PZZ455. Small Craft Advisory until 3 PM
PDT Saturday for PZZ475.



Visit us at

Follow us on Facebook and Twitter at:

For forecast zone information
see the forecast zone map online: is the U.S. government's official web portal to all federal, state and local government web resources and services.