High Wind in California, March 30 to 31, 2017

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
506 PM PDT Thu Mar 30 2017

...update for new aviation discussion...

.SYNOPSIS...
An upper level trough will continue move through the Great Basin
through early Friday bringing widespread strong to locally
damaging northerly winds to the area. High pressure and weak
offshore flow will bring warmer weather to the region this
weekend. A fast moving trough passing north of the area will
support a brief drop in temperatures early next week.

&&

.SHORT TERM...(TDY-SUN)

Northerly winds slowly starting to develop this afternoon, maybe
just a few hours delayed from what was expected. Still expecting
winds to peak this evening into very early Friday morning (pre-
dawn hours) before weakening through mid morning to below advisory
levels. Strongest in the I5 corridor where gusts up to around 80
mph are possible. Winds expected to filter down into the LA Basin
during the evening and overnight with gusts to around 45 mph,
strongest in the Hollywood Hills and down into West LA. SB south
coast already seeing some gusty winds this afternoon and those too
will peak in the early evening but remain gusty most of the night
into Friday morning.

After winds subside Friday morning they are expected to remain
well below advisory levels through Saturday morning, with the
possible exception of SB South coast which again could flirt with
some low end advisory level winds Friday evening.

Highs Friday expected to cool a couple more degrees as colder air
behind the trough passage moves in.

By Saturday with ridging starting to develop and gradients turning
offshore temps are expected to jump several degrees back up in the
80s for the valleys and 70s to around 80 for interior coastal
zones. The models today backed off a little on the strength of the
offshore flow and support aloft so right now it looks like any
Santa Ana winds should remain below advisory levels.

Sunday should be almost a carbon copy of Saturday, though
increasing onshore flow will likely lead to some cooling at the
coast.

.LONG TERM...(MON-THU)

Models seem to be in agreement today showing the Monday trough to
be weak and scoot rapidly into the Rockies rather than diving
south and bringing another round of gusty north winds with it.
This could change but it seems more of the solutions lately have
favored this weaker and more progressive scenario. Probably some
cooling Monday with moderate onshore flow and a cooler air mass
overall, but then turning warmer Tue-Thu and very weak offshore
flow combines with a strengthening ridge aloft. Highs in the lower
90s possible for the valleys both days and 80s for interior
coastal plain.

&&

.AVIATION...31/0000Z

At 2255Z, the inversion at KLAX was 2300 ft deep. The top of the
inversion was at 3200 ft with a temperature of 13 deg C.

Generally hi confidence in the 00Z TAFs. VFR conditions are expected
at all the airfields thru Fri, except there should be a period of
IFR vsbys at KPMD thru about 03Z this evening due to blowing dust.
Gusty w to nw winds will prevail thru this evening and again Fri
afternoon at most of the coastal airfields. Gusty n winds will
affect KBUR tonight with some low level wind shear possible, and
KVNY thru Fri. Very strong winds will affect KPMD and KWJF thru
tonight, with gusts up to 45 KT expected, contributing to the
reduced vsbys in blowing dust at KPMD. There is also a 20 percent
chance of IFR vsbys at KWJF in blowing dust this evening.

KLAX...Generally hi confidence in the 00Z TAF with VFR conditions
expected thru Fri evening. Gusty n winds will affect the airfield
from about 03Z to 11Z, with gusts up to 32 kt, altho there is the
potential for higher gusts. The winds may not last thru 11Z, or be
gusty at times thru the period.

KBUR...Hi confidence in the 00Z TAF with VFR conditions expected
thru Fri afternoon. Gusty n winds can be expected this evening, with
low level wind shear possible thru late tonight.

&&

.MARINE...30/230 PM

Gale level winds will develop this afternoon across the outer
waters and along the Central Coast as Small Craft Advisory level
winds develop in the inner waters south of Point Conception.
Winds will begin to diminish late Friday but will remain elevated
through Saturday morning.

The strongest winds will be in the western portions of all zones.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 10 AM PDT Saturday for
      zones 34-35. (See LAXCFWLOX).
     Wind Advisory in effect until 9 PM PDT this evening for zones
      34>36-40. (See LAXNPWLOX).
     High Wind Warning in effect until 8 AM PDT Friday for zones
      39-46-52>54. (See LAXNPWLOX).
     Beach Hazards Statement in effect through Friday afternoon
      for zones 40-41-87. (See LAXCFWLOX).
     Wind Advisory in effect until 8 AM PDT Friday for zones
      41-44-45-87-547. (See LAXNPWLOX).
     Wind Advisory in effect until 6 PM PDT this evening for zone
      46. (See LAXNPWLOX).
     High Wind Warning in effect until 3 AM PDT Friday for zones
      59-88. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 6 PM PDT this evening
      for zone 645. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Friday for zone 645.
      (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Saturday for
      zones 650-655. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Saturday for zones
      670-673-676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK...(SUN-THU)
No significant hazards expected.

&&

PUBLIC...MW
AVIATION...Sirard
MARINE...Kj
SYNOPSIS...Munroe

weather.gov/losangeles

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OXNARD CA
508 PM PDT THU MAR 30 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0503 PM     NON-TSTM WND DMG 1 E PEARBLOSSOM         34.50N 117.89W
03/30/2017                   LOS ANGELES        CA   TRAINED SPOTTER

            A LARGE STREET SIGN BROKE OFF HINGES ON ONE SIDE AND WAS
            DANGLING FROM TRAFFIC LIGHT POST OVER TRAFFIC IN CITY OF
            PALMDALE AT AVE R8 AND 47TH STREET AST. THE SW CORNER AT
            INTERSECTION OF HWY 138 AND AVE R8. PEAK WIND AT EVENT
            TIME WAS 36 MPH.

&&

SETO

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
633 PM PDT THU MAR 30 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0457 PM     NON-TSTM WND GST 6 SSW CASTAIC LAKE      34.57N 118.74W
03/30/2017  M59 MPH          LOS ANGELES        CA   MESONET

            MESONET STATION WHITAKER PEAK /WTPC1/.

&&

NWS LOS ANGELES/OXNARD CA
IRIS SYSTEM

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
634 PM PDT THU MAR 30 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0556 PM     NON-TSTM WND GST 13 W LANCASTER          34.73N 118.39W
03/30/2017  M55 MPH          LOS ANGELES        CA   MESONET

            MESONET STATION POPPY PARK /PPPC1/.

&&

NWS LOS ANGELES/OXNARD CA
IRIS SYSTEM