Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 040403
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
903 PM PDT THU SEP 3 2015
BELOW AVERAGE TEMPERATURES THROUGH SATURDAY AS A WEATHER SYSTEM
IMPACTS THE REGION. SHOWERS AND THUNDERSTORMS POSSIBLE ACROSS THE
NORTHERN PORTION OF THE STATE FRIDAY INTO SATURDAY MORNING WITH A
DUSTING OF SNOW OVER LASSEN PEAK, FOLLOWED BY SOME BREEZY
OFFSHORE WINDS THIS WEEKEND. WARMER WEATHER RETURNS SUNDAY INTO
.DISCUSSION (TONIGHT THROUGH SUNDAY)...
A few showers occurred earlier in the evening over northwestern
Shasta County and to the north but have long since died off. The
trough of low pressure is now centered over the Pacific
Northwest. The trough will continue to deepen over the area
through Friday to bring cooler than normal temperatures to the
area...Upper 70s to lower 80s valley to mainly 50s and 60s for the
mountains. Friday will be the coolest day this week.
This trough does not look like it will bring widespread
precipitation to most of the interior at this time. As the
central part of the trough deepens over the area on Friday and
Friday night it will bring the best chance of showers and isolated
thunderstorms to the northern third. In the mountains...mainly
over Plumas county the NAM model has indicated some enhanced
activity late at night over Plumas County for two nights in a
Snow levels will lower enough over the northern mountains that
Lassen Park may get a dusting of snow Friday night. Instability
looks pretty good for Friday as the system moves through so some
isolated thunderstorms will be possible late in the day through
Friday night...especially around Plumas County at night.
The trough will likely generate breezy conditions at times on
Friday especially over the ridges and through the delta.
Saturday the trough will move to the northeast with northerly
winds over the interior and any showers will end by mid morning.
This will start a warming trend but temperatures are still
expected to stay below normal for this time of year. Northerly
flow will continue on Sunday and temperatures are expected to
warm to around seasonal normals.
.EXTENDED DISCUSSION (Monday THROUGH Thursday)
Dry conditions through the extended forecast period...as ridge
gradually builds over California. Temperatures will warm to
slightly above normal levels.
UPR LOW OVER PACIFIC NW DIGS S ALG W CST WITH WLY FLOW. VFR CONDS
OVR INTR NORCAL NXT 24 HRS EXC LCL MVFR CIGS POSS IN SHWRS OVR
SHASTA MTNS AFT 12Z FRI. ISOLD TSRA AFT 22Z NRN MTNS. LCL SWLY
SFC WND GSTS TO 25 KTS THRU DELTA AND OVR HYR TRRN AFT 16Z.