Area Forecast Discussion
Issued by NWS Eureka, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

FXUS66 KEKA 152156

National Weather Service Eureka CA
256 PM PDT Sun Sep 15 2019

.SYNOPSIS...Cloud cover and rain will continue to spread across the
area as a cold front moves through Northwest California. Scattered
showers will linger into Monday, with noticeably cooler temperatures
inland. Another storm system will bring a second dose of rain later
on Tuesday and into Wednesday. Drier weather with a warming trend is
expected late week and into next weekend.


.DISCUSSION...The fist widespread rain event of the season will
continue to unfold today across Northwest California as a cold front
spreads wet and cooler conditions eastward. The bulk of the
precipitation is expected to fall in the vicinity of the front
later this evening and tonight, though scattered showers will
linger across portions of the area through tomorrow. Rain along
the front will be moderate to locally heavy at times. The main
trough will move overhead late tonight/early tomorrow and
instability will slightly increase across portions of the area as
a result. Though marginal, instability should be enough for some
moderate to heavy showers, and possibly some thunder across
portions of the area from tonight through early tomorrow evening.
Confidence is not high on the thunder chances, but the best
opportunity would be tonight across portions of the northern
waters and immediate adjacent coastline, and tomorrow afternoon
over portions of the interior. The trough will exit the region
late on Monday, and Tuesday will see a dry start to the day across
most of the area. Yet another trough is set to impact the area
during the later half of Tuesday. Rain will begin to spread
southeastward across the area beginning mid to late morning on
Tuesday. Highest totals will be for portions of Del Norte and
interior Humboldt counties. Showers are expected to linger through
Thursday, with high pressure forecast to build into the region in
the wake of the mid-week trough. As a result, warm and dry
conditions will return to interior portions of the Northwest


.AVIATION...A cold front is beginning to impact the region with LIFR
conditions reported at CEC. Ceilings will continue to fall from
north to south across Northwest California, bringing LIFR
eventually to ACV this evening. Periods of moderate, to at times
heavy rain, will occur just ahead of and with the frontal passage.
Ceilings will also descend in the Ukiah area but without reliable
observations detailed updates will be impossible overnight. With
airport minimums around 1,800 feet, there is a high likelihood
these will be met tonight and updates may not be too critical.

Conditions will improve on Monday as the front moves farther inland
and mixing increases. Expect on and off showers across the region
and a slight chance of a thunderstorm behind the front, with the
best chances near CEC overnight. Winds will be fairly light at all
of the TAF sites through the forecast period. /RPA


.MARINE...A cold front will quickly move through the waters this
evening turning winds from out of the south back to the north by
Monday morning. Winds will remain fairly light for at least the
next 24-48 hours. Another front will approach the waters on
Tuesday bringing another brief period of south winds. This time a
few gusts to over 25 kt could be possible in the extreme northern
portion of the waters but overall winds will continue to remain
light. Thus, locally developed seas will remain small but a
northwesterly swell around 10-12 seconds will build seas to just
below small craft criteria at around 7-8 feet Monday into Tuesday.
A brief uptick in sea heights may occur on Wednesday behind the
next front with a small window for small craft conditions

Typical summer northerly winds and steeper seas will likely
redevelop late in the week as high pressure builds back over the
eastern Pacific. /RPA




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.