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000 
FXUS66 KMTR 262051
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1251 PM PST Sun Feb 26 2017

.SYNOPSIS...Showers will be possible across the region from late 
tonight through Monday as a frontal system moves across the 
region. Rainfall accumulation will generally be light with snow 
showers in the higher elevations. Dry weather conditions then 
return for the remainder of the workweek along with a gradual 
warming trend as high pressure builds aloft.

&&

.DISCUSSION...as of 12:50 PM PST Sunday...Aside from CU 
developing over the mountains/hills this afternoon, mostly sunny 
conditions prevail ahead of an approaching weather system to our 
north. The latest forecast models and current trends bring a 
frontal boundary across the region late this evening and through 
the overnight hours with isolated to scattered showers likely. 
These showers will likely impact the North Bay late this evening 
or tonight and shift southward through the Central Coast overnight
into Monday morning. Rainfall amounts in the range of a few 
hundredths of an inch to a couple tenths will be possible yet not 
all locations will pick up measurable precipitation. In addition, 
snow levels are forecast to lower again to the 3,000-3,500 foot 
range along the Central Coast with below 3,000 northward. Thus, 
should see some snow showers across the region with light 
accumulation in the higher elevations. Meanwhile, overnight 
temperatures will remain in the 30s to lower 40s as this system 
will bring a reinforcing shot of cooler air across the region.

Lingering showers will be possible into Monday morning before 
diminishing in coverage by the afternoon and evening. Dry weather 
conditions are then likely for the remainder of the week as high 
pressure builds out over the eastern Pacific. Temperatures will 
also begin a gradual warming trend late in the week with 
widespread 60s likely by Thursday and Friday. Overnight 
temperatures will also moderate some and only cool into the upper 
30s to lower 40s by late week, compared to the lower/mid 30s more 
common the next few nights. 

The upper level ridge is forecast to weaken a bit by the upcoming
weekend as a mid/upper level through approaches the Pacific 
Northwest. At this time, the best chance of precipitation will be 
north of the region yet cannot rule out the system clipping the 
far northern portion of the North Bay by Saturday night into 
Sunday. However, not expecting widespread heavy rainfall with most
locations remaining dry across the region through the extended 
forecast period. 

&&

.AVIATION...As of 03:34 AM PST Sunday...Generally VFR through the
forecast period although any passing showers could quickly lower
conditions rapidly. Models generally increase shower activity
after 05Z so trended toward that in the TAFs with VCSH. Moderate
confidence.

Vicinity of KSFO...Mostly VFR expect during showers. VCSH expected
starting around 06Z. Generally light winds this morning 
increasing to 10-15 kt West to Northwesterly flow by this 
afternoon. Moderate confidence.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. Light winds. Possible shower or two
after 05Z so added VCSH. Moderate to high confidence.

&&

.BEACHES...A Beach Hazard Statement was issued for the threat of
Sneaker Waves on Sunday. A long period swell arriving Sunday
morning, along with fair weather and light morning winds, will 
bring a moderate risk of Sneaker Waves to North Bay and Bay Area 
coastal beaches. Arrival of the long period swell will coincide
with a rapidly rising tide on Sunday morning, pushing more energy
up the beach. West and Northwest facing and steep sloped beaches 
will be at greatest risk. The threat is expected to abate in the
afternoon as the tide drops, onshore winds develop, and long
period waves transition to shorter periods. BFG

&&

.MARINE...as of 09:23 AM PST Sunday...A weak system will enter the
area tonight bringing moderate to  fresh northerly conditions
along with a few showers. Monday onward conditions should remain 
moderate to fresh with possible near gale conditions later this 
week. No significant swell trains are expected through the 
period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...None.

$$

PUBLIC FORECAST: RGass
AVIATION: Bell
MARINE: Bell


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