Our system grabs the NWS technical discussion each hour. This page is definitely for people with serious forecast needs, as the report is extremely technical. What it does do that other forecast products do not, however, is give you a sense of what the forecasters are thinking about and what larger weather patterns might be forming. If you’re a weather geek, you’ll find this interesting - else - “move along, nothing to see here” 
The NWS has a glossary of many of the terms and abbreviations used in the discussion forecast on this page.
FXUS66 KMTR 091159
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
400 AM PST TUE FEB 9 2010
.DISCUSSION…AS OF 3:42 AM PST TUESDAY…SHOWERS THROUGH
TONIGHT WITH SNOW LEVELS DOWN TO 3000 FEET IN MONTEREY COUNTY.
KMUX DOPPLER RADAR IS INDICATING WIDE SPREAD SHOWERS ACROSS THE CWA
THIS MORNING. THE LATEST SATELLITE WATER VAPOUR IMAGE IS SHOWING
AN UPPER-LEVEL LOW PRESSURE SYSTEM SLIDING DO SOUTH ALONG THE CENTRAL
COAST. THIS LOW IS TRIGGERING THE SHOWERS AND WILL BRING SNOW
LEVELS DOWN TO 3000 FEET IN MONTEREY COUNTY. SNOW WILL BE POSSIBLE
ELSEWHERE WITH SNOW LEVELS CLOSER TO 4000 TO 5000 FEET.
MODEL SOLUTIONS HAVE SHIFTED THE POSITION OF THE UPPER LEVEL LOW
SIGNIFICANTLY WEST COMPARED TO PREVIOUS MODEL RUNS. THIS HAS LEAD TO
THE DECISION TO REMOVE THE WINTER WEATHER ADVISORY FROM THE EAST BAY
HILLS AND DIABLO RANGE AS WELL AS THE SANTA CRUZ MOUNTAINS.
THIS SHIFT TO A MORE WESTERLY ROUTE WILL PROMOTE HIGHER SNOW LEVELS
OVER THESE AREAS WITH SNOW LEVELS EXPECTED TO BE ABOVE 4000 FEET
WHILE PRECIPITATION IS ACTUALLY OCCURRING. CURRENTLY BEN LOMOND
LOCATED AT 2600 IS AT 39 DEGREES F AND MT DIABLO LOCATED AT 3800
FEET IS AROUND 36 DEGREES F. ADDITIONALLY… THE BODEGA BAY WIND
PROFILER IS INDICATING A SNOW LEVEL OF AROUND 5000 FEET.
AS MENTIONED ABOVE THE WINTER WEATHER ADVISORY HAS BEEN DROPPED
OVER MOST AREAS WITH THE EXCEPTION OF THE SANTA LUCIA MOUNTAINS AND
LOS PADRES NATIONAL FOREST. ACCORDING TO THE 0900 UTC RUC ANALYSIS
THE UPPER LEVEL LOW COULD BRUSH BY THIS AREA DROPPING SNOW LEVELS
TO 3000 FEET AND LOCALLY TO 2500 FEET DURING PERIODS WHEN
PRECIPITATION WOULD BE FALLING. THIS WILL RESULT IN SNOW
ACCUMULATIONS OF 3 TO 5 INCHES OVER THE NEXT 12 HOURS PROMPTING A
WINTER WEATHER ADVISORY FOR ELEVATIONS GREATER THAN 3000 FEET IN
THIS AREA.
ONCE THIS LOW PASSES SOUTH A RIDGE OF HIGH PRESSURE WILL BUILD OVER
THE EASTERN PACIFIC LEAVING THE AREA DRY THROUGH THURSDAY MORNING.
CURRENT MODEL SOLUTIONS SLIDE A WEAK SHORT WAVE ACROSS THE NORTHBAY
AREA THURSDAY RESULTING IN INCREASED CLOUDS AND A CHANCE OF RAIN
WHICH IS EXPECTED TO SLIDE SOUTH FRIDAY MORNING.
AFTER FRIDAY…A RIDGE DEVELOPS OVER CALIFORNIA KEEPING THE STORM
TRACK JUST NORTH OF THE REGION. AT THIS POINT WILL NOT MENTION RAIN
IN THE FORECAST FOR THE WEEKEND…BUT WILL REINTRODUCE THE
SLIM POSSIBILITY OF RAIN SUNDAY NIGHT THROUGH EARLY NEXT WEEK.
&&
.AVIATION…AS OF 4:00 AM TUESDAY…UPPER LOW JUST WEST OF KSFO AT
POST TIME. SURFACE BOUNDARY HAS ALREADY MOVED THROUGH AND WINDS AT
KSFO AND KOAK HAVE ALREADY SHIFTED TO WESTERLY…WITH A NOTED WIND
SHIFT ALREADY NOTED AT THE BUOYS AND COASTAL SITES. EXPECT KSJC TO
SHIFT SHORTLY WITH KNUQ ALREADY WSW. SHOWERS ARE NUMEROUS AS OF 12Z
WITH PEAK IN AREAL COVERAGE EXPECTED BETWEEN NOW AND 18Z…THEN
RAPIDLY DECREASING THROUGH MIDDAY AND AFTERNOON HOURS.
VICINITY OF KSFO…WEST WINDS TODAY MAINLY UNDER 12 KT. LIGHT RAIN
THIS MORNING WITH CIGS IN THE 3-5K RANGE…DECREASING RAPIDLY AFTER
18Z AS THE UPPER LOW SHIFTS SOUTH.
KSFO BRIDGE APPROACH…SIMILAR TO KSFO…BUT MORE WIDESPREAD PRECIP
EXPECTED OVER THE SOUTH END OF THE BAY DUE TO CLOSER PROXIMITY TO THE
UPPER LOW THIS MORNING.
MRY BAY AREA TERMINALS…WINDS HAVE SHIFT WESTERLY AT KMRY AND KSNS.
SHOWERS WILL CONTINUE TO MOVE ONSHORE THIS MORNING AND LINGER A
LITTLE LONGER AT THESE TERMINALS THROUGH MIDDAY AS UPPER LOW SHIFT
SOUTHWARD DOWN THE COAST. LOOKS PRETTY CLEAR THIS EVENING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES…
.TDY…WINTER WEATHER ADVISORY ABOVE 3000 FEET FOR
SANTA LUCIA MTNS AND LOS PADRES NATIONAL FOREST
STARTING 6AM THIS MORNING.
.SCA…FOR ALL COASTAL WATERS AND MONTEREY BAY
PUBLIC FORECAST: LARRY
AVIATION/MARINE: RWW
NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO
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