Area Forecast Discussion
Issued by NWS Sacramento, 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 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KSTO 210835
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
135 AM PDT Tue Oct 21 2014

.Synopsis...
Dry zonal flow will persist through Wednesday with some high
clouds at times. An elongated frontal system impacts northern CA
with potential rain from Wednesday night into the weekend. Chances
for the southern areas to receive precipitation increase Friday
and Saturday. Significant rainfall is possible over the far
northern sections of the state through Saturday.

&&

.Short Term Discussion (Tonight through Thursday)...

Low pressure area has moved into Nevada and zonal dry flow will
set up behind the front for Today with just some high clouds
moving through the area. A low pressure area in the gulf of Alaska
will start to spread precipitation along the northwest coast late
Wednesday and into the far northern interior sections of the state
Wednesday night into Thursday. Late Wednesday night and Thursday
is when chances increase mainly for areas north of I-80.

As the low deepens on Thursday night into Friday the front begins
to shift and become a little bit more oriented north to south.
This may dry out the eastern interior sections while the coastal
range may continue to see some precipitation. Friday night and
Saturday is when the front pushes inland given areas the greatest
chance of widespread rain over the entire interior along with some
higher elevation snow and windy conditions. Significant rainfall is
likely over the mountains of Shasta county into the weekend. Five
plus inches for the favored south and southwestern facing slopes
looks possible.



.Extended Discussion (Saturday through Tuesday)

Timing is still not consistent but models do end up bringing a
decent system through the interior Friday night and Saturday. Both
the European and GFS indicate rain spreading through the interior
Friday night. The GFS is a bit faster clearing out during the day
on Saturday while the European tries to linger the system around
into Sunday. This system in addition to the higher elevation snow
and windy conditions will likely bring thunderstorms to the
interior.

The European then develops a ridge over the area while the GFS
keeps a zonal flow pattern over the Pacific. If the GFS pattern
works out then some more rain for the far northern sections of the
state will be possible by Tuesday of next week.

&&

.Aviation...

VFR conditions in the valley today with decreasing clouds and
winds generally 10 kt or less. Areas of MVFR cigs and vsbys in
the mountains through 12z with LCL LIFR/IFR conditions in isolated
showers, then improving to VFR by 18z as low pressure exits. EK

&&

.STO Watches/Warnings/Advisories...
None.
&&

$$






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.