FXUS66 KSTO 052321
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 321 PM PST SUN FEB 5 2012
 
 .SHORT TERM DISCUSSION...
 
 A NICE WINTER SUNDAY WITH SCATTERED HIGH CLOUDS AND TEMPERATURES
 IN THE MID 60S IN THE VALLEY AND MID 40S TO 50S IN THE MOUNTAINS
 WITH HIGH PRESSURE OVER THE AREA. TEMPERATURES ARE THE SAME TO A
 TAD WARMER THAN YESTERDAY AFTERNOON SO FAR WHICH ARE ABOUT 4 TO 9
 DEGREES ABOVE NORMAL. HIGH PRESSURE STARTS TO WEAKEN TOMORROW WITH
 A TROUGH DIGGING OVER THE EASTERN PACIFIC APPROACHING THE WEST
 COAST. TEMPERATURES FOR MONDAY ARE EXPECTED TO BE SIMILAR TO
 TODAY. TEMPERATURES COOL ABOUT 5 TO 10 DEGREES ON TUESDAY WITH A
 SPLITTING SYSTEM APPROACHING THE WEST COAST.
 
 THE TROUGH OVER THE EASTERN PACIFIC IS EXPECTED TO SPLIT INTO TWO
 AS IT NEARS THE WEST COAST. ALTHOUGH THERE IS STILL SOME
 UNCERTAINTY IN THE TRACK THAT THE SYSTEM WILL TAKE. IT LOOKS LIKE
 THE SYSTEM STRETCHES OUT ALONG THE CALIFORNIA COAST AND THE
 MAJORITY OF THE ENERGY WILL FORM A CLOSED LOW OFF THE
 SOUTHERN CALIFORNIA COAST TUESDAY. THE OFFSHORE TRACK OF THIS
 SYSTEM WILL FAVOR THE MOST PRECIPITATION ALONG THE WEST SIDE OF
 INTERIOR NORTHERN CALIFORNIA. PRECIPITABLE WATER PLUME ALMOST AN INCH
 ALONG THE COAST AND FROM THE BAY AREA SOUTH. PRECIPITATION AMOUNTS
 OF AROUND A QUARTER TO HALF AN INCH ARE POSSIBLE ALONG THE COASTAL
 RANGE AND INTO LAKE COUNTY AND IN THE DELTA REGION. OTHERWISE
 PRECIPITATION AMOUNTS ARE GENERALLY EXPECTED TO BE AROUND A TENTH
 OF AN INCH OR LESS. SNOW LEVELS ARE EXPECTED TO BE AROUND 4000 TO
 5000 FEET WITH ACCUMULATIONS LOCALLY UP TO 4 INCHES POSSIBLE IN
 THE COASTAL RANGE. GUSTY SOUTHEAST WINDS UP TO AROUND 40 MPH ARE
 POSSIBLE OVER THE RIDGES. PRECIPTATION IS EXPECTED TO TAPER OFF
 WEDNESDAY MORNING AS THE SYSTEM MOVES SOUTHEAST. ALTHOUGH THE
 ECMWF BRINGS A SHORTWAVE TROUGH INTO THE PACIFIC NORTHWEST
 BRUSHING BY FAR NORTHERN CALIFORNIA MID MORNING WEDNESDAY. THE GFS
 BRINGS THIS SYSTEM FURTHER NORTH WITH RIDGE OF HIGH PRESSURE
 BUILDING BACK INTO THE AREA. THE FORECAST DOES NOT MENTION
 PRECIPITATION FOR WEDNESDAY FOR NOW BUT INCREASED POPS SLIGHTLY
 FOR THE TREND UPWARD IF THE ECMWF CONTINUES WITH THE SYSTEM
 BRUSHING BY THE NORTH WEDNESDAY MORNING. THE RIDGE SHOULD
 DEFINITELY BUILD BACK IN BY WEDNESDAY EVENING DIMINISHING ANY
 THREAT OF PRECIPITATION. TEMPERATURES SHOULD WARM UP TO A LITTLE
 ABOVE NORMAL ON WEDNESDAY WITH CLEARING SKIES AND DRY NORTHERLY
 WINDS.
 
 
 .EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)
 
 EXTENDED MODELS CONTINUE TO SHOW HIGH PRESSURE RIDGING OVER THE
 WEST COAST WITH ABOVE NORMAL TEMPERATURES AND DRY WEATHER THURSDAY
 INTO FRIDAY. BY FRIDAY NIGHT INTO SATURDAY...THE GEM...GFS...ECMWF
 SHOW THE POSSIBILITY OF A STORM MOVING INTO NORCAL. AT THIS
 POINT...THE GFS HAS A WEAKER SYSTEM THAN THE GEM WITH VERY LITTLE
 PRECIPITATION. THE ECMWF HAS ALSO BACKED OFF ON PRECIP FOR
 SATURDAY. HAVE KEPT A SLIGHT CHANCE OF SHOWERS ALONG THE COASTAL
 RANGE AND NORTHERN MTNS FOR SATURDAY. INCREASED POPS FOR SUNDAY
 SINCE THE ECMWF...GEM AND GFS ADVERTISE ANOTHER WAVE DROPPING INTO
 NORCAL.    JBB
 
 &&
 
 .AVIATION...
 
 VFR CONDITIONS WILL PERSIST OVER INTERIOR NORCAL FOR THE NEXT 24
 HOURS AS A RIDGE OF HIGH PRESSURE DOMINATES THE AREA. PATCHY BR WITH
 MVFR VISBYS IN THE NORTHERN SAN JOAQUIN VALLEY IS POSSIBLE AGAIN
 MONDAY MORNING FROM 12-16Z...ALTHOUGH THE LIKELIHOOD IS DIMINISHED IN
 COMPARISON TO THE PREVIOUS MORNING AS CONDITIONS ARE DRIER. LIGHT
 WINDS LESS THAN 10KTS ARE EXPECTED THROUGH THE PERIOD. -DVC
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 051626
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 826 AM PST SUN FEB 5 2012
 
 .SHORT TERM DISCUSSION...
 
 ANOTHER PLEASANT DAY WITH ABOVE NORMAL HIGH TEMPERATURES (BY ABOUT
 3 TO 8 DEGREES) WITH HIGH PRESSURE REMAINING OVER THE AREA TODAY.
 TEMPERATURES ARE EXPECTED TO BE SIMILAR TO YESTERDAY WITH HIGHS IN
 THE VALLEY IN THE MID 60S AND 40S TO 50S IN THE MOUNTAINS.
 ALTHOUGH THERE MAY BE A FEW MORE HIGH CLOUDS TODAY AHEAD OF AN
 APPROACHING SYSTEM. HIGH PRESSURE STARTS TO WEAKEN TOMORROW WITH A
 DEEP TROUGH OVER THE EASTERN PACIFIC APPROACHING THE WEST COAST.
 TEMPERATURES FOR MONDAY ARE EXPECTED TO BE SIMILAR TO TODAY.
 TEMPERATURES COOL ABOUT 5 TO 10 DEGREES ON TUESDAY WITH A
 SPLITTING SYSTEM APPROACHING THE WEST COAST.
 
 THE TROUGH OVER THE EASTERN PACIFIC IS EXPECTED TO SPLIT INTO TWO
 AS IT NEARS THE WEST COAST. ALTHOUGH THERE IS STILL SOME
 UNCERTAINTY IN THE TRACK THAT THE SYSTEM WILL TAKE. IT LOOKS LIKE
 THE SOUTHERN PORTION OF THE ENERGY WILL FORM A CLOSED LOW OFF THE
 SOUTHERN CALIFORNIA COAST TUESDAY. THE OFFSHORE TRACK OF THIS
 SYSTEM WILL FAVOR THE MOST PRECIPITATION TOWARDS WESTERN PORTION OF
 OUR FORECAST AREA WITH AMOUNTS AROUND A QUARTER TO HALF AN INCH
 POSSIBLE ALONG THE COASTAL RANGE AND INTO LAKE COUNTY AND IN THE
 DELTA REGION. OTHERWISE PRECIPITATION AMOUNTS ARE GENERALLY
 EXPECTED TO BE LESS THAN A TENTH OF AN INCH. SNOW LEVELS ARE
 EXPECTED TO BE AROUND 5000 TO 6000 FEET WITH ACCUMULATIONS LOCALLY
 UP TO 4 INCHES POSSIBLE IN THE COASTAL RANGE. PRECIPITATION IS
 EXPECTED TO DIMINISH ON WEDNESDAY AS THE HIGH PRESSURE STARTS
 BUILDING BACK INTO THE AREA.
 
 .EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)
 
 GEM...ECMWF AND GFS ALL IN GOOD AGREEMENT FOR THURSDAY WITH HIGH
 AMPLITUDE RIDGE OVER THE WEST COAST. DAYTIME HIGHS UNDER SUNNY
 SKIES ARE FORECAST TO BE 10 TO 15 DEGREES ABOVE NORMAL. GEM AND
 ECMWF BEGIN TO BREAK DOWN RIDGE ON FRIDAY AS A PACIFIC FRONTAL
 SYSTEM MOVES INTO THE WEST COAST BUT GFS HOLDS STRONG KEEPING
 PACIFIC SYSTEM OFFSHORE. CONSIDERING STRENGTH OF RIDGE...HAVE GONE
 WITH THE DRIER GFS FOR FRIDAY. IF GFS IS CORRECT THEN SATURDAY
 WILL BE DRY AS WELL BUT EVEN GFS BRINGS PACIFIC TROUGH TO NEAR THE
 COAST BY SATURDAY AFTERNOON. HAVE THEREFORE INCLUDED SLIGHT THREAT
 POPS FOR SATURDAY OVER THE NORTHERN MOUNTAINS AND NORTHERN COASTAL
 RANGE. ON SUNDAY...ALL MODELS HAVE SOME SORT OF TROUGH ALONG THE
 WEST COAST WITH PRECIP OVER THE CWA. DETAILS DIFFER BUT WITH THIS
 MUCH AGREEMENT IN DAY SEVEN EXTENDED MODELS...BELIEVE AT LEAST
 CLIMO POPS ARE WARRANTED.
 
 &&
 
 .AVIATION...
 
 VFR CONDS WILL PERSIST OVER INTERIOR NORCAL FOR THE NEXT 24 HOURS.
 PATCHY BR WITH MVFR VISBYS IN THE NRN SAN JOAQUIN VLY IS LIKELY
 TO DEVELOP AGAIN MONDAY MORNING BTWN 10-16Z. LIGHT WINDS LESS THAN
 10KTS ARE EXPECTED THROUGH THE PERIOD.  JBB
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 051211
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 411 AM PST SUN FEB 5 2012
 
 .SHORT TERM DISCUSSION...
 
 OVERALL PATTERN HAS CHANGED VERY LITTLE THE LAST FEW DAYS WITH A
 REX BLOCK OVER THE ROCKIES AND A HIGH AMPLITUDE TROUGH OVER THE
 NORTHEASTERN PACIFIC. SKIES ARE MOSTLY CLEAR ACROSS INTERIOR
 NORTHERN CALIFORNIA...THOUGH HIGH CLOUDS ARE ON THE INCREASE IN
 ADVANCE OF A PACIFIC NORTHWEST SYSTEM. DRY BOUNDARY LAYER
 CONDITIONS AND THESE HIGH CLOUDS ARE DETERRING FOG FORMATION THIS
 MORNING. 
 
 ALTHOUGH HIGH CLOUDS SHOULD CONTINUE TO STREAM ACROSS THE AREA...
 EXPECT ANOTHER PLEASANT DAY TODAY ACROSS NORCAL UNDER THE
 INFLUENCE OF HIGH PRESSURE. CENTRAL VALLEY TEMPS SHOULD REACH THE
 MID 60S THIS AFTERNOON...WITH 40S AND 50S FORECAST OVER THE HIGHER
 ELEVATIONS. UPPER RIDGE AXIS WILL BEGIN TO SHIFT EAST MONDAY...BUT
 FORECAST HIGHS FOR TOMORROW ARE SIMILAR TO TODAY.
 
 THE PATTERN WILL BEGIN TO CHANGE LATE MONDAY INTO TUESDAY AS A
 HIGH AMPLITUDE TROUGH APPROACHES NORCAL. THIS SYSTEM WILL BEGIN TO
 SPLIT AS IT APPROACHES THE COAST...THE SYSTEM IS NOW FORECAST TO
 PARALLEL THE COAST AS IT DROPS SOUTH TUE AND WED. SPLITTING
 SYSTEMS USUALLY ARENT EFFECTIVE PRECIPITATION MAKERS...BUT THIS
 SYSTEM DOES APPEAR TO HOLD IT TOGETHER LONG ENOUGH FOR MOST AREAS
 TO SEE AT LEAST LIGHT PRECIPITATION DURING THE DAY TUESDAY. THE
 OFFSHORE TRACK OF THIS SYSTEM WILL FAVOR THE MOST PRECIPITATION
 TOWARDS THE SOUTHERN AND WESTERN PORTIONS OF OUR FORECAST
 AREA. ALSO... THE FLOW ALOFT WILL BE NEARLY PARALLEL TO THE
 SIERRA SO OROGRAPHICS WONT BE A FACTOR. IN FACT...THE ECMWF KEEPS
 THE SIERRA ENTIRELY DRY.
 
 RESIDUAL SHOWERS MAY LINGER INTO TUESDAY EVENING BEFORE TAPERING
 OFF AS THE SYSTEM DIVES SOUTH. SUBSIDENCE INCREASES ON WEDNESDAY
 AS THE EASTERN PACIFIC RIDGE REBUILDS INTO NORCAL. DANG
 
 
 .EXTENDED DISCUSSION (THURSDAY THROUGH SUNDAY)
 
 GEM...ECMWF AND GFS ALL IN GOOD AGREEMENT FOR THURSDAY WITH HIGH
 AMPLITUDE RIDGE OVER THE WEST COAST. DAYTIME HIGHS UNDER SUNNY
 SKIES ARE FORECAST TO BE 10 TO 15 DEGREES ABOVE NORMAL. GEM AND
 ECMWF BEGIN TO BREAK DOWN RIDGE ON FRIDAY AS A PACIFIC FRONTAL
 SYSTEM MOVES INTO THE WEST COAST BUT GFS HOLDS STRONG KEEPING
 PACIFIC SYSTEM OFFSHORE. CONSIDERING STRENGTH OF RIDGE...HAVE GONE
 WITH THE DRIER GFS FOR FRIDAY. IF GFS IS CORRECT THEN SATURDAY
 WILL BE DRY AS WELL BUT EVEN GFS BRINGS PACIFIC TROUGH TO NEAR THE
 COAST BY SATURDAY AFTERNOON. HAVE THEREFORE INCLUDED SLIGHT THREAT
 POPS FOR SATURDAY OVER THE NORTHERN MOUNTAINS AND NORTHERN COASTAL
 RANGE. ON SUNDAY...ALL MODELS HAVE SOME SORT OF TROUGH ALONG THE
 WEST COAST WITH PRECIP OVER THE CWA. DETAILS DIFFER BUT WITH THIS
 MUCH AGREEMENT IN DAY SEVEN EXTENDED MODELS...BELIEVE AT LEAST
 CLIMO POPS ARE WARRANTED.
 
 &&
 
 .AVIATION...
 
 VFR CONDITIONS ARE EXPECTED OVER INTERIOR NORCAL FOR THE NEXT 24
 HOURS AS A RIDGE OF HIGH PRESSURE HOLDS IN PLACE ALONG THE WEST
 COAST. ONLY EXCEPTION IS THE POSSIBILITY OF PATCHY FOG WITH MVFR
 VISBYS IN THE NORTHERN SAN JOAQUIN VALLEY THIS MORNING. LIGHT
 WINDS LESS THAN 10KTS ARE EXPECTED THROUGH THE PERIOD.
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 050600
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 1000 PM PST SAT FEB 4 2012
 
 .SHORT TERM DISCUSSION...
 
 BLOCKING PATTERN OVER THE INTERIOR WRN STATES GAVE INTERIOR NORCAL 
 ANOTHER SEASONABLY WARM DAY WITH MAX TEMPS ON SAT A FEW DEG WARMER 
 THAN FRI OVER MOST OF THE AREA. DURING THE DAY ON SUN...HIGH 
 CLOUDINESS OVER THE ERN PAC WILL SPREAD INLAND...AND THICKEN ON MON. 
 MINOR SYNOPTIC WARMING WILL LIKELY BE SUPPRESSED BY THICKENING CLOUD 
 COVER ESPECIALLY ON MON...AHEAD OF AN APPROACHING SPLITTING TROF. 
 UNTIL THEN...DRY AND STILL SEASONABLY MILD WX WILL CONTINUE WITH 
 MINIMAL EARLY MORNING FOG. 
 
 ENERGY IN THE FORM OF A MODERATELY STRONG CLOSED LOW IS FORECAST TO 
 SPLIT OFF FROM THE ERN PAC TROF...AND ENCOUNTER RESISTANCE FROM THE 
 HIGHLY AMPLIFIED RIDGE ALONG THE W COAST. THE GFS/ECMWF/GEM ARE IN 
 GOOD AGREEMENT OF THE CLOSED LOW DROPPING SEWD AND PARALLELING THE 
 CA COAST TUE AND WED. RIDGING QUICKLY REBUILDS ALONG THE COAST AS 
 THE CLOSED LOW MOVES OVER BAJA. THE ASSOCIATED PW PLUME...ALMOST 
 ORIENTED N TO S ALONG THE CA COAST...IS ALSO FORECAST TO SPLIT ON
 TUE. THE TRACK OF THE CLOSED LOW REMAINING OFFSHORE AND THE
 SPLITTING PW PLUME DO NOT BODE WELL FOR WIDESPREAD SIGNIFICANT
 PRECIP FOR INTERIOR NORCAL. FOR EXAMPLE...THE BUFKIT QPFS RANGE
 FROM A .10 INCH AT RDD TO .20 INCH AT BLU TO .30 AT SAC TO .40 AT
 SCK TO .80 AT SUU AND AN INCH AT UKI. ONE CAN SEE THAT THE
 OFFSHORE TRACK OF THE CLOSED LOW WILL FAVOR HIGHER QPFS OVER THE
 FAR WRN AND SRN PORTIONS OF OUR FORECAST AREA IN INTERIOR NORCAL.
 LITTLE QPF IS EXPECTED IN THE FAR NRN ZONES AND OVER THE SIERNEV
 AS THE MID-LEVEL FLOW WILL PARALLEL THE SIERNEV /NIL-WEAK OROGRAPHICS/.
 THUS...THIS SYSTEM WILL NOT HAVE A SIGNIFICANT IMPACT ON NORCAL
 RESERVOIRS. JHM
 
 .EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
 
 AS THE TUESDAY STORM SYSTEM MOVES SOUTH OF OUR CWA BY EARLY
 WEDNESDAY...ANOTHER HIGH AMPLITUDE RIDGE BUILDS INTO NORCAL. THE
 ECMWF...GFS...AND GEM MODELS ARE ALL SHOWING GOOD AGREEMENT WITH
 THE RIDGE PATTERN FROM WEDNESDAY THROUGH EARLY FRIDAY. THIS WILL
 BRING A PERIOD OF ABOVE NORMAL TEMPERATURES AND DRY WEATHER WITH
 FAIRLY CLEAR SKIES. ANOTHER STORM SYSTEM APPROACHES THE WEST
 COAST ON FRIDAY AND COULD POTENTIALLY BRING SOME LIGHT RAIN TO
 INTERIOR NORCAL ON SATURDAY. CONFIDENCE IS NOT HIGH ON THIS SYSTEM
 SINCE THE 06Z MODELS HAD VARIED SOLUTIONS, BUT THE 12Z RUNS SHOW
 MORE CONSISTENCY.  JBB
 
 
 &&
 
 .AVIATION...
 
 VFR CONDITIONS ARE EXPECTED TO DOMINATE OVER INTERIOR NORCAL FOR
 THE NEXT 24 HOURS AS A  RIDGE OF HIGH PRESSURE HOLDS IN PLACE
 ALONG THE WEST COAST. ONLY EXCEPTION IS THE POSSIBILITY OF PATCHY FOG
 WITH MVFR VISBYS IN THE NORTHERN SAN JOAQUIN VALLEY EARLY TOMORROW
 MORNING...ALTHOUGH THE PROBABILITY OF FOG FORMING IS A BIT LOWER
 THAN YESTERDAY AS CONDITIONS ARE DRIER. LIGHT WINDS 

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 042222
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 222 PM PST SAT FEB 4 2012
 
 .SHORT TERM DISCUSSION...
 
 A STRONG RIDGE OF HIGH PRESSURE REMAINS IN PLACE THROUGH MONDAY.
 850 MB TEMPERATURES WILL WARM A LITTLE FOR SUNDAY AND MONDAY AND
 TEMPERATURES ARE EXPECTED TO BE SLIGHTLY WARMER THAN TODAY. LITTLE 
 IF ANY FOG IS EXPECTED THE NEXT COUPLE OF MORNINGS WITH THE ONLY
 POSSIBLE PLACES OCCURRING NEAR WATERWAYS AND IN THE CENTRAL PART 
 OF THE VALLEY.
 
 FOR SUPERBOWL SUNDAY EXPECT A WARM DAY WITH HIGHS MAINLY IN THE
 LOW TO MID 60S FOR THE CENTRAL VALLEY AND A NUMBER OF FOOTHILL
 LOCATIONS TO THE 40S TO LOWER 50S FOR THE MOUNTAINS. SOME HIGH
 CLOUDS MAY MOVE ACROSS THE INTERIOR DURING THE DAY BUT EXPECT
 MOSTLY SUNNY SKIES TO PREVAIL.
 
 THE RIDGE WILL BREAK DOWN ON TUESDAY WITH THE MOISTURE ALONG 30N
 AND 155W THAT EXTENDS FURTHER TO THE WEST IS THE AREA THAT WILL
 EVENTUALLY BREAK THROUGH THE RIDGE TO BRING US CHANGES OF
 PRECIPITATION ON TUESDAY AND TUESDAY NIGHT. IF THERE IS A BREAK
 THROUGH THE SYSTEM DOES NOT LOOK LIKE IT WILL END UP BEING A BIG
 EVENT FOR THE INTERIOR. THE SYSTEM IS SHOWING SIGNS OF SPLITTING
 WITH THE THE MAIN PART OF THE LOW HEADING SOUTH INTO SOUTHERN
 CALIFORNIA. THE BEST CHANCES OF RAIN WILL OCCUR DURING THE DAY ON
 TUESDAY AND ANY LINGERING SHOWERS FROM THIS SYSTEM WOULD QUICKLY
 DIMINISH TUESDAY EVENING OVER THE INTERIOR.
 
 .EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
 
 AS THE TUESDAY STORM SYSTEM MOVES SOUTH OF OUR CWA BY EARLY
 WEDNESDAY...ANOTHER HIGH AMPLITUDE RIDGE BUILDS INTO NORCAL. THE
 ECMWF...GFS...AND GEM MODELS ARE ALL SHOWING GOOD AGREEMENT WITH
 THE RIDGE PATTERN FROM WEDNESDAY THROUGH EARLY FRIDAY. THIS WILL
 BRING A PERIOD OF ABOVE NORMAL TEMPERATURES AND DRY WEATHER WITH
 FAIRLY CLEAR SKIES. ANOTHER STORM SYSTEM APPROACHES THE WEST
 COAST ON FRIDAY AND COULD POTENTIALLY BRING SOME LIGHT RAIN TO
 INTERIOR NORCAL ON SATURDAY. CONFIDENCE IS NOT HIGH ON THIS SYSTEM
 SINCE THE 06Z MODELS HAD VARIED SOLUTIONS, BUT THE 12Z RUNS SHOW
 MORE CONSISTENCY.  JBB
 
 
 &&
 
 .AVIATION...
 
 VFR CONDS WILL DOMINATE FOR THE NEXT 24 HOURS...EXCEPT FOR LCL MVFR 
 CONDS IN THE SRN SAC AND NRN SAN JOAQUIN VLYS BTWN 10-17Z.
 LIGHT WINDS LESS THAN 10 KTS CONTINUE AT THE TAF SITES.  JBB
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...NONE. 
 
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 041716
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 916 AM PST SAT FEB 4 2012
 
 .SHORT TERM DISCUSSION...
 
 A STRONG RIDGE OF HIGH PRESSURE REMAINS IN PLACE THROUGH MONDAY.
 850 MB TEMPERATURES WILL BE SLIGHTLY COOLER TODAY BUT WARM A LITTLE
 FOR SUNDAY AND MONDAY. LITTLE IF ANY FOG IS EXPECTED THE NEXT
 COUPLE OF MORNINGS WITH THE ONLY POSSIBLE PLACES OCCURRING NEAR
 WATERWAYS AND THE CENTRAL PART OF THE VALLEY.
 
 FOR SUPERBOWL SUNDAY EXPECT A WARM DAY WITH HIGHS MAINLY IN THE
 60S FOR THE CENTRAL VALLEY AND A NUMBER OF FOOTHILL LOCATIONS TO
 THE 40S AND 50S IN THE MOUNTAINS. SOME HIGH CLOUDS MAY MOVE
 ACROSS THE INTERIOR DURING THE DAY BUT EXPECT MOSTLY SUNNY SKIES
 TO PREVAIL.
 
 THE RIDGE WILL BREAK DOWN ON TUESDAY WITH THE MOISTURE ALONG 30N
 AND 160W THAT EXTENDS FURTHER TO THE WEST IS THE AREA THAT WILL
 EVENTUALLY BREAK THROUGH THE RIDGE TO BRING US CHANGES OF
 PRECIPITATION ON TUESDAY AND TUESDAY NIGHT. IF THERE IS A BREAK
 THROUGH THE SYSTEM DOES NOT LOOK LIKE IT WILL END UP BEING A BIG
 EVENT FOR THE INTERIOR.
 
 .EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
 
 EXTENDED MODELS NOW ALL HAVE UPPER LOW WELL SOUTH OF THE CWA BY
 12Z WEDNESDAY. MAY STILL BE ENOUGH INSTABILITY AND MOISTURE AROUND
 DURING THE MORNING HOURS FOR SOME ISOLATED LIGHT SHOWERS BUT
 PRECIP THREAT WILL BE SHIFTING RAPIDLY SOUTHWARD DURING THE
 MORNING HOURS. SKIES SHOULD BE CLEARING BY AFTERNOON WITH DAYTIME
 HIGHS FORECAST TO BOUNCE BACK UP TO WELL ABOVE NORMAL. REMAINDER
 OF WEEK LOOKS DRY UNDER UPPER RIDGING REBUILDING ALONG THE WEST
 COAST WITH LIGHT WINDS AND DAYTIME HIGHS 5 TO 10 DEGREES ABOVE
 NORMAL. MODELS DIVERGE AS WE MOVE INTO NEXT WEEKEND. GEM...GFS AND
 ECMWF ALL BRING PACIFIC FRONTAL SYSTEM TOWARDS THE COAST FRIDAY
 BUT THEN HANDLE IF DIFFERENTLY. ECMWF HOLDS SYSTEM OFFSHORE AT
 LEAST THROUGH SATURDAY. LATEST GEM AND GFS BRING TAIL END OF THIS
 SYSTEM INTO NORCAL ON SATURDAY BUT HAVE BEEN VERY INCONSISTENT
 FROM RUN TO RUN. HAVE KEPT NEXT SATURDAY DRY FOR NOW GOING WITH
 MORE CONSISTENT ECMWF.
 
 &&
 
 .AVIATION...
 
 VFR AND LIGHT WINDS NEXT 24 HOURS. LCL MVFR NORTHERN SAN JOAQUIN
 VALLEY THIS MORNING IN PATCHY FOG WHICH SHOULD DISSIPATE BY 18Z.
 JBB
 
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 041134
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 334 AM PST SAT FEB 4 2012
 
 .SHORT TERM DISCUSSION...
 
 NEARLY STATIONARY UPPER LEVEL RIDGE AXIS REMAINS OVER THE
 REGION...TRANSITIONING TO A REX BLOCK OVER THE ROCKIES. LOOKING AT
 INFRARED SATELLITE IMAGERY...A NARROW BAND OF HIGH CLOUDINESS HAS
 REMAINED OVER PORTIONS OF INTERIOR NORCAL FOR MUCH OF THE NIGHT.
 THIS COMBINED WITH SLIGHTLY DRIER BOUNDARY LAYER CONDITIONS... HAS
 INHIBITED FOG FORMATION THIS MORNING.
 
 OVERALL PATTERN WILL CHANGE VERY LITTLE TODAY AND THROUGH THE
 WEEKEND AS THE REX BLOCK REMAINS IN PLACE. LOOK FOR HIGHS TO REACH
 AROUND THE MID 60S TODAY AND TOMORROW ACROSS THE CENTRAL VALLEY...
 WITH 40S AND 50S OVER THE HIGHER ELEVATIONS. WE SHOULD BEGIN TO
 SEE MORE IN THE WAY OF HIGH CLOUDINESS MOVING OVERHEAD SUNDAY.
 THIS CLOUDINESS SHOULD HELP TO DETER FOG FORMATION THE NEXT FEW
 MORNINGS.
 
 A HIGHLY AMPLIFIED TROUGH OVER THE NORTHERN PACIFIC WILL BEGIN TO
 APPROACH THE AREA MONDAY...HELPING TO PUSH THE UPPER RIDGE
 EASTWARD. BY MONDAY NIGHT THE SYSTEM BEGINS TO SPLIT. THERE
 REMAINS CONSIDERABLE UNCERTAINTY IN THE MODELS. THE ECMWF HAS BEEN
 FAIRLY CONSISTENT SPLITTING THE UPPER LOW OFF THE COAST...BRINGING
 MOST OF THE ENERGY INLAND OVER SOUTHERN CALIFORNIA. THE GFS BRINGS
 THE SYSTEM INLAND OVER THE BAY AREA AND WOULD BE A WETTER SOLUTION
 FOR NORCAL. AT THIS POINT WE REMAIN CAUTIOUSLY OPTIMISTIC THAT
 NORCAL WILL SEE PRECIPITATION...THOUGH ANY PRECIP THAT DOES FALL
 WILL LIKELY STAY ON THE LIGHT SIDE. DANG
 
 
 .EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)
 
 EXTENDED MODELS NOW ALL HAVE UPPER LOW WELL SOUTH OF THE CWA BY
 12Z WEDNESDAY. MAY STILL BE ENOUGH INSTABILITY AND MOISTURE AROUND
 DURING THE MORNING HOURS FOR SOME ISOLATED LIGHT SHOWERS BUT
 PRECIP THREAT WILL BE SHIFTING RAPIDLY SOUTHWARD DURING THE
 MORNING HOURS. SKIES SHOULD BE CLEARING BY AFTERNOON WITH DAYTIME
 HIGHS FORECAST TO BOUNCE BACK UP TO WELL ABOVE NORMAL. REMAINDER
 OF WEEK LOOKS DRY UNDER UPPER RIDGING REBUILDING ALONG THE WEST
 COAST WITH LIGHT WINDS AND DAYTIME HIGHS 5 TO 10 DEGREES ABOVE
 NORMAL. MODELS DIVERGE AS WE MOVE INTO NEXT WEEKEND. GEM...GFS AND
 ECMWF ALL BRING PACIFIC FRONTAL SYSTEM TOWARDS THE COAST FRIDAY
 BUT THEN HANDLE IF DIFFERENTLY. ECMWF HOLDS SYSTEM OFFSHORE AT
 LEAST THROUGH SATURDAY. LATEST GEM AND GFS BRING TAIL END OF THIS
 SYSTEM INTO NORCAL ON SATURDAY BUT HAVE BEEN VERY INCONSISTENT
 FROM RUN TO RUN. HAVE KEPT NEXT SATURDAY DRY FOR NOW GOING WITH
 MORE CONSISTENT ECMWF.
 
 &&
 
 .AVIATION...
 
 VFR NEXT 24 HOURS EXCEPT AREAS OF MVFR NORTHERN SAN JOAQUIN VALLEY
 THIS MORNING IN PATCHY FOG THROUGH ABOUT 18Z. GENERALLY LIGHT
 WINDS EXPECTED. 
 
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 040533
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 933 PM PST FRI FEB 3 2012
 
 .DISCUSSION...
 WEAK UPPER RIDGE OVER NORCAL REMAINS THROUGH THE WEEKEND WITH LITTLE 
 CHANGE IN THE WEATHER EXPECTED. MINOR UPDATES TO FORECAST FOR 
 TONIGHT AND SATURDAY WITH SLIGHTLY LOWER DEWPOINTS IN THE SAC AREA 
 SOUTHWARD INTO THE NORTHERN SAN JOAQUIN PORTENDING LESS POTENTIAL 
 FOR WIDESPREAD FOG TONIGHT AND EARLY SATURDAY...AND POSSIBLY A 
 LITTLE COOLER MIN TEMPS EARLY SATURDAY WITH PATCHY FROST IN THE 
 VALLEY. UPDATES OUT.
 
 &&
 
 .PREVIOUS SHORT TERM DISCUSSION...
 RIDGE ALONG THE W COAST TRANSITIONS TO AN OMEGA-REX BLOCK OVER THE 
 WRN STATES THROUGH THE WEEKEND. CURRENT 500 MBS STREAMLINE ANALYSIS 
 SHOWS A METEOROLOGICAL COL/SADDLE JUST INLAND FROM THE COAST 
 RESULTING IN LIGHTER WINDS AND WEAKER UPPER AIR SUPPORT THAN 
 YESTERDAY. THE NLY AND ELY GRADIENTS HAVE DRASTICALLY WEAKENED THIS 
 AFTERNOON WHICH HAS ALLOWED DEWPOINTS AND HUMIDITIES TO RECOVER. 
 AFTERNOON TEMPS WERE RUNNING SOME 1 TO 9 DEG COOLER THAN 
 YESTERDAY...AND WITH A LACK OF SIGNIFICANT ADIABATIC WARMING 
 TODAY...MAX TEMPS SHOULD END-UP A LITTLE COOLER OVER MOST LOCATIONS 
 THAN YESTERDAY.
 
 DURING THE WEEKEND...THE REX PORTION OF THE BLOCK IS FORECAST TO 
 RETROGRADE...WHICH MAY KEEP WEAK CYCLONIC FLOW AND MINOR COOLING 
 OVER NORCAL AS SUGGESTED BY THE NAM...BUT MUCH LESS SO AS SUGGESTED 
 BY THE GFS. WE HAVE FAVORED THE LATTER...AND KEPT THE COLDER AIR AND 
 ANY POSSIBLE BACKWASH CLOUDINESS EAST OF THE CREST. GIVEN THE WRN 
 STATES BLOCKING PATTERN...THE MORNING RH PROGS SHOWED A LOT LESS  
 MOISTURE W OF 130W SPREADING INLAND ON SUN AS THEY DID YESTERDAY. 
 THUS...WITH MOSTLY CLEAR SKIES...LIGHT WINDS AND RECOVERING 
 DEWPOINTS...LOW CLOUDS AND PATCHY DENSE FOG ARE POSSIBLE IN THE
 VALLEY DURING THE NEXT COUPLE OF MORNINGS.
 
 THE MOISTURE AHEAD OF THE TROF IS CURRENTLY ELONGATING/STRETCHING AS 
 IT NEARS 130W. A DEFORMATION AXIS JUST INLAND FROM THE COAST IS 
 EXPECTED TO ERODE/BLOCK MUCH OF THE HIGHER CLOUDINESS FROM SPREADING 
 INLAND UNTIL SUN NITE/MON. THE GFS DOES NOT SPREAD MOISTURE AT/BELOW 
 700 MBS UNTIL MON NITE WHEN WE INTRODUCE OUR INITIAL POPS. 
 
 CAUTIOUS OPTIMISM CONTINUES FOR AT LEAST A LITTLE/SOME QPF FALLING 
 IN OUR AREA MAINLY TUE. THE TROF IS FORECAST TO SPLIT AS IT NEARS 
 THE COAST AND RUNS INTO THE WRN BLOCK. SPLITTING SYSTEMS DON`T 
 PRODUCE SIGNIFICANT PRECIP...BUT IT WILL BE AT LEAST...SOMETHING.
 
 NCEP GLOBAL ENSEMBLE MEAN OUT THROUGH THE MIDDLE OF THE MONTH DOES
 NOT REALLY SHOW APPRECIABLE CHANGE...MAINLY KEEPING THE RIDGE
 ALONG THE COAST AND SUGGESTING OCCASIONAL WEAKENING OR SPLITTING 
 TROFS AFFECTING NORCAL.  JHM
 
 &&
 
 .EXTENDED DISCUSSION (TUESDAY THROUGH FRIDAY)...
 MODELS CONTINUE TO DIFFER WITH HANDLING OF THE SYSTEM FOR LATE 
 MONDAY THROUGH TUESDAY. ECMWF HI-RES...WHICH HAS BEEN THE MOST 
 CONSISTENT RUN TO RUN...CONTINUES TO CLOSE OFF THE LOW WELL WEST OF 
 THE CWA TUESDAY THEN DIG IT SOUTH OFF THE CALIFORNIA COAST TUESDAY 
 NIGHT INTO WEDNESDAY. LATEST 12Z RUN KEEPS THE CWA DRY THROUGH THE 
 EVENT. 18Z OPER GFS CONTINUES THE TREND OF THE LAST SEVERAL RUNS 
 WHERE IT KEEPS THE WAVE MORE CONSOLIDATED AS IT MOVES ONSHORE OVER 
 NORCAL THEN DIGS AND CLOSES IT OFF AS IT TRACKS THROUGH. THE LATEST 
 GEM SOLUTION LOOKS MORE LIKE THE ECMWF HI-RES BUT TRACKS THE LOW 
 CLOSER TO THE COAST WITH SOME MAINLY LIGHT QPF OVER THE CWA TUESDAY. 
 CURRENT FORECAST FOLLOWS THIS COMPROMISE SOLUTION WITH HIGHER POPS 
 ADVERTISED FARTHER WEST ON TUESDAY WITH LINGERING SHOWERS MAINLY 
 SOUTHERN PORTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING AS 
 THE LOW MOVES FARTHER SOUTH ALONG THE CALIFORNIA COAST.
 
 MODELS IN AGREEMENT IN REBUILDING RIDGING ALONG THE WEST COAST 
 BEHIND THIS SYSTEM WITH DRY WEATHER FORECAST THROUGH THE REMAINDER 
 OF THE WEEK.  PCH
 
 &&
 
 .AVIATION...
 HIGH PRESSURE CONTINUES OVER THE AREA WITH GENERAL VFR CONDITIONS. 
 PATCHY FOG WILL BRING IFR/LIFR TO THE NORTHERN SAN JOAQUIN AND 
 SOUTHERN SACRAMENTO VALLEYS SATURDAY MORNING THROUGH ABOUT 18Z. 
 GENERALLY LIGHT WINDS EXPECTED THROUGH TOMORROW. EK
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...NONE.
 
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 032343
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 343 PM PST FRI FEB 3 2012
 
 .SHORT TERM DISCUSSION...
 
 RIDGE ALONG THE W COAST TRANSITIONS TO AN OMEGA-REX BLOCK OVER THE 
 WRN STATES THROUGH THE WEEKEND. CURRENT 500 MBS STREAMLINE ANALYSIS 
 SHOWS A METEOROLOGICAL COL/SADDLE JUST INLAND FROM THE COAST 
 RESULTING IN LIGHTER WINDS AND WEAKER UPPER AIR SUPPORT THAN 
 YESTERDAY. THE NLY AND ELY GRADIENTS HAVE DRASTICALLY WEAKENED THIS 
 AFTERNOON WHICH HAS ALLOWED DEWPOINTS AND HUMIDITIES TO RECOVER.
 AFTERNOON TEMPS WERE RUNNING SOME 1 TO 9 DEG COOLER THAN
 YESTERDAY...AND WITH A LACK OF SIGNIFICANT ADIABATIC WARMING
 TODAY...MAX TEMPS SHOULD END-UP A LITTLE COOLER OVER MOST
 LOCATIONS THAN YESTERDAY.
 
 DURING THE WEEKEND...THE REX PORTION OF THE BLOCK IS FORECAST TO 
 RETROGRADE...WHICH MAY KEEP WEAK CYCLONIC FLOW AND MINOR COOLING 
 OVER NORCAL AS SUGGESTED BY THE NAM...BUT MUCH LESS SO AS SUGGESTED 
 BY THE GFS. WE HAVE FAVORED THE LATTER...AND KEPT THE COLDER AIR AND 
 ANY POSSIBLE BACKWASH CLOUDINESS EAST OF THE CREST. GIVEN THE WRN 
 STATES BLOCKING PATTERN...THE MORNING RH PROGS SHOWED A LOT LESS  
 MOISTURE W OF 130W SPREADING INLAND ON SUN AS THEY DID YESTERDAY. 
 THUS...WITH MOSTLY CLEAR SKIES...LIGHT WINDS AND RECOVERING 
 DEWPOINTS...LOW CLOUDS AND PATCHY DENSE FOG ARE POSSIBLE IN THE
 VALLEY DURING THE NEXT COUPLE OF MORNINGS.
 
 THE MOISTURE AHEAD OF THE TROF IS CURRENTLY ELONGATING/ STRETCHING
 AS IT NEARS 130W. A DEFORMATION AXIS JUST INLAND FROM THE COAST
 IS EXPECTED TO ERODE/BLOCK MUCH OF THE HIGHER CLOUDINESS FROM
 SPREADING INLAND UNTIL SUN NITE/MON. THE GFS DOES NOT SPREAD
 MOISTURE AT/BELOW 700 MBS UNTIL MON NITE WHEN WE INTRODUCE OUR
 INITIAL POPS. 
 
 CAUTIOUS OPTIMISM CONTINUES FOR AT LEAST A LITTLE/SOME QPF
 FALLING IN OUR AREA MAINLY TUE. THE TROF IS FORECAST TO SPLIT AS
 IT NEARS THE COAST AND RUNS INTO THE WRN BLOCK. SPLITTING SYSTEMS
 DON`T PRODUCE SIGNIFICANT PRECIP...BUT IT WILL BE AT LEAST...SOMETHING.
 
 NCEP GLOBAL ENSEMBLE MEAN OUT THROUGH THE MIDDLE OF THE MONTH DOES
 NOT REALLY SHOW APPRECIABLE CHANGE...MAINLY KEEPING THE RIDGE
 ALONG THE COAST AND SUGGESTING OCCASIONAL WEAKENING OR SPLITTING
 TROFS AFFECTING NORCAL. JHM
 
 
 .EXTENDED DISCUSSION (TUESDAY THROUGH FRIDAY)
 
 MODELS CONTINUE TO DIFFER WITH HANDLING OF THE SYSTEM FOR LATE 
 MONDAY THROUGH TUESDAY. ECMWF HI-RES...WHICH HAS BEEN THE MOST 
 CONSISTENT RUN TO RUN...CONTINUES TO CLOSE OFF THE LOW WELL WEST OF 
 THE CWA TUESDAY THEN DIG IT SOUTH OFF THE CALIFORNIA COAST TUESDAY 
 NIGHT INTO WEDNESDAY. LATEST 12Z RUN KEEPS THE CWA DRY THROUGH THE 
 EVENT. 18Z OPER GFS CONTINUES THE TREND OF THE LAST SEVERAL RUNS 
 WHERE IT KEEPS THE WAVE MORE CONSOLIDATED AS IT MOVES ONSHORE OVER 
 NORCAL THEN DIGS AND CLOSES IT OFF AS IT TRACKS THROUGH. THE LATEST 
 GEM SOLUTION LOOKS MORE LIKE THE ECMWF HI-RES BUT TRACKS THE LOW 
 CLOSER TO THE COAST WITH SOME MAINLY LIGHT QPF OVER THE CWA TUESDAY. 
 CURRENT FORECAST FOLLOWS THIS COMPROMISE SOLUTION WITH HIGHER POPS 
 ADVERTISED FARTHER WEST ON TUESDAY WITH LINGERING SHOWERS MAINLY 
 SOUTHERN PORTIONS OF THE CWA TUESDAY NIGHT INTO WEDNESDAY MORNING AS 
 THE LOW MOVES FARTHER SOUTH ALONG THE CALIFORNIA COAST.
 
 MODELS IN AGREEMENT IN REBUILDING RIDGING ALONG THE WEST COAST 
 BEHIND THIS SYSTEM WITH DRY WEATHER FORECAST THROUGH THE REMAINDER 
 OF THE WEEK.
 PCH
 
 
 &&
 
 .AVIATION...
 
 HIGH PRESSURE CONTINUES OVER THE AREA WITH GENERAL VFR CONDITIONS.
 PATCHY FOG WILL BRING IFR/LIFR TO THE NORTHERN SAN JOAQUIN AND SOUTHERN
 SACRAMENTO VALLEYS SATURDAY MORNING THROUGH ABOUT 18Z. GENERALLY
 LIGHT WINDS EXPECTED THROUGH TOMORROW. EK
 
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...NONE.
 
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 031743
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 943 AM PST FRI FEB 3 2012
 
 .SHORT TERM DISCUSSION...
 
 RIDGE ALONG THE W COAST TRANSITIONS TO AN OMEGA-REX BLOCK OVER THE 
 WRN STATES THROUGH THE WEEKEND. CURRENT 500 MBS STREAMLINE
 ANALYSIS SHOWS A METEOROLOGICAL COL/SADDLE ALONG THE COAST
 RESULTING IN LIGHTER WINDS AND WEAKER UPPER AIR SUPPORT THAN
 YESTERDAY. THE NLY GRADIENTS HAVE DRASTICALLY WEAKENED BUT THE ELY
 GRADIENTS REMAIN MODERATELY STRONG. ALSO...WATER VAPOR IMAGERY
 SHOWS THE STRONGER SUBSIDENCE HAS SHIFTED S AND E OF INTERIOR
 NORCAL. THUS...WINDS HAVE DECREASED OVER THE SIERNEV AND THIS WILL
 ALLOW DEWPOINTS AND HUMIDITIES TO RECOVER. MID MORNING TEMPS ARE
 RUNNING SOME 5-12 DEG COOLER THAN YESTERDAY...AND WITH A LACK OF
 SIGNIFICANT ADIABATIC WARMING TODAY...MAX TEMPS ARE EXPECTED TO BE
 A FEW DEG COOLER OVER MOST LOCATIONS. A DEFORMATION AXIS ALONG THE
 COAST IS KEEPING A BAND OF HIGH CLOUDS FROM PROGRESSING EWD.
 
 DURING THE WEEKEND...THE REX PORTION OF THE BLOCK IS FORECAST TO 
 RETROGRADE...WHICH MAY KEEP WEAK CYCLONIC FLOW AND MINOR COOLING 
 OVER NORCAL AS SUGGESTED BY THE NAM...BUT MUCH LESS SO AS SUGGESTED 
 BY THE GFS. HOWEVER...ANY BACKWASH CLOUDS ARE EXPECTED TO REMAIN E 
 OF OUR CWA. GIVEN THE WRN STATES BLOCKING PATTERN...THE MORNING RH 
 PROGS SHOW A LOT LESS OF THE MOISTURE W OF 130W SPREADING INLAND ON 
 SUN AS THEY DID YESTERDAY. THIS MOISTURE IS CURRENTLY ELONGATING/ 
 STRETCHING AS IT NEARS 130W...AND WE MAY NEED TO SHOW A LITTLE MORE 
 SUNSHINE IN OUR GRIDS FOR THE WEEKEND...ESP SUNDAY. 
 
 CAUTIOUS OPTIMISM CONTINUES FOR AT LEAST A LITTLE/SOME QPF FALLING 
 IN OUR AREA MAINLY TUE. THE TROF IS FORECAST TO SPLIT AS IT NEARS
 THE COAST AND RUNS INTO THE WRN BLOCK. SPLITTING SYSTEMS DON`T PRODUCE
 SIGNIFICANT PRECIP...BUT IT WILL BE AT LEAST...SOMETHING.  
 
 NCEP GLOBAL ENSEMBLE MEAN OUT THROUGH THE MIDDLE OF THE MONTH DOES
 NOT REALLY SHOW APPRECIABLE CHANGE...MAINLY KEEPING THE RIDGE
 ALONG THE COAST AND SUGGESTING OCCASIONAL WEAKENING OR SPLITTING
 TROFS AFFECTING NORCAL. JHM
 
 
 .EXTENDED DISCUSSION (TUESDAY THROUGH FRIDAY)
 
 BRIEF CHANGE IN WEATHER PATTERN EXPECTED ON TUESDAY WITH ALL
 EXTENDED MODELS PUSHING A PACIFIC FRONTAL SYSTEM INTO THE NORCAL
 COAST BY MID DAY TUESDAY. ABNORMALLY STRONG RIDGE OF HIGH PRESSURE
 OVER THE WESTERN U.S. LIKELY TO TAKE A BIG TOLL ON THIS SYSTEM
 HOWEVER AND IT IS NOT LIKELY TO BE A BIG PRECIP PRODUCER. GFS
 CURRENTLY THE STRONGEST WITH THIS SYSTEM WITH THE SYSTEM HOLDING
 TOGETHER ENOUGH TO BRING AT LEAST LIGHT PRECIP TO MUCH OF THE
 CWA. CONSIDERING SIGNIFICANT STRENGTH OF RIDGE...PREFER THE ECMWF
 SOLUTION WHICH SPLITS THE SYSTEM TO THE NORTH AND SOUTH LEAVING
 NORCAL DRY...OR UNDER LIGHT PRECIP. EITHER WAY...COOLING IS IN
 STORE FOR NEXT TUESDAY UNDER INCREASED CLOUD COVER AND A COOLER
 AIRMASS. ALL SCENARIOS QUICKLY BUILD RIDGE BACK UP OVER THE WEST
 FOR A DRY PERIOD THROUGH THE REMAINDER OF THE EXTENDED PERIOD AND
 A RETURN TO ABOVE NORMAL DAYTIME HIGH TEMPERATURES. ANOTHER
 PACIFIC STORM SYSTEM IS FORECAST TO APPROACH THE COAST BY THE END
 OF NEXT WEEK BUT WITH STRONG HIGH PRESSURE FIRMLY IN PLACE OVER
 THE WEST IT IS LIKELY TO SEE THE SAME FATE AS THE TUESDAY SYSTEM.
 
 
 &&
 
 .AVIATION...
 
 HI PRES CONTS WITH VFR CONDS OVR INTR NORCAL EXC AREAS IFR/LIFR IN 
 ST/FOG IN NRN SAN JOAQUIN VLY TIL ARND 20Z AND IN SRN SAC/NRN SAN 
 JOAQUIN VLYS BTWN 08Z-21Z SAT. AREAS N-E SFC WND GSTS 25 KTS OR GTR 
 OMTNS NXT 24 HRS.
 
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...NONE.
 
 &&
 
 $$

  NWS STO Office Area Forecast Discussion
  

   
 FXUS66 KSTO 031135
 AFDSTO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SACRAMENTO CA
 335 AM PST FRI FEB 3 2012
 
 .SHORT TERM DISCUSSION...
 
 A STRONG UPPER RIDGE IS THE DOMINANT FEATURE ACROSS THE WEST
 COAST. THE ASSOCIATED SUBSIDENCE IS BRINGING MAINLY CLEAR SKIES
 ACROSS THE FORECAST AREA. PATCHY FOG HAS BEGUN TO FORM IN THE
 CENTRAL VALLEY MAINLY IN AREAS ADJACENT TO THE DELTA. ALSO OF NOTE
 ON WATER VAPOR SATELLITE IMAGERY IS A RATHER BROAD AREA OF
 CYCLONIC CIRCULATION CENTERED OVER THE COLORADO ROCKIES. THIS
 SYSTEM HAS BROUGHT LOCALLY BREEZY NORTHEAST WINDS TO THE SIERRA.
 HOWEVER...THERE ISNT MUCH IN THE WAY OF UPPER LEVEL SUPPORT FOR
 THESE WINDS...SO THEY SHOULD REMAIN PRIMARILY CONFINED TO
 FAVORABLY-ORIENTED SIERRA CANYONS. WITH MUCH LIGHTER WINDS THAN
 LAST NIGHT...TEMPERATURES ACROSS THE FORECAST AREA FOR THE MOST
 PART ARE RUNNING MUCH COOLER THAN 24 HOURS AGO.
 
 SURFACE GRADIENTS WILL CONTINUE TO SLACKEN TODAY AS THE UPPER
 RIDGE AXIS SHIFTS OVERHEAD. WE WILL PROBABLY STILL SEE SOME NORTH
 WINDS UP TO 10 MPH...MAINLY WEST OF THE SACRAMENTO RIVER. WE`LL
 LOSE THE ADIABATIC WARMING EFFECTS TODAY WITH LIGHTER WINDS...SO
 AFTERNOON HIGHS SHOULD BE A FEW DEGREES COOLER THAN YESTERDAY. LOOK
 FOR TEMPERATURES TO CLIMB BACK INTO THE 60S ACROSS THE CENTRAL
 VALLEY...WITH 40S AND 50S OVER THE HIGHER ELEVATIONS. THESE TEMPS
 ARE STILL 5 TO 10 DEGREES WARMER THAN NORMAL.
 
 LITTLE CHANGE IS EXPECTED THROUGH THE WEEKEND AS HIGH PRESSURE
 REMAINS OVERHEAD. WE`LL PROBABLY CONTINUE TO SEE SOME PATCHY
 MORNING FOG IN THE USUAL AREAS (IN THE CENTRAL VALLEY SACRAMENTO
 SOUTHWARD)...BUT WIDESPREAD DENSE FOG IS NOT ANTICIPATED.
 
 WEATHER PATTERN BEGINS TO SHIFT ON MONDAY AS A HIGHLY AMPLIFIED
 TROUGH OVER THE NORTHERN PACIFIC APPROACHES THE WEST COAST.
 INITIAL IMPACTS FOR MONDAY WILL BE LIMITED...JUST INCREASING CLOUD
 COVER WITH PERHAPS THE MOUNTAIN WINDS BEGINNING TO PICK UP. DANG
 
 
 .EXTENDED DISCUSSION (TUESDAY THROUGH FRIDAY)
 
 BRIEF CHANGE IN WEATHER PATTERN EXPECTED ON TUESDAY WITH ALL
 EXTENDED MODELS PUSHING A PACIFIC FRONTAL SYSTEM INTO THE NORCAL
 COAST BY MID DAY TUESDAY. ABNORMALLY STRONG RIDGE OF HIGH PRESSURE
 OVER THE WESTERN U.S. LIKELY TO TAKE A BIG TOLL ON THIS SYSTEM
 HOWEVER AND IT IS NOT LIKELY TO BE A BIG PRECIP PRODUCER. GFS
 CURRENTLY THE STRONGEST WITH THIS SYSTEM WITH THE SYSTEM HOLDING
 TOGETHER ENOUGH TO BRING AT LEAST LIGHT PRECIP TO MUCH OF THE
 CWA. CONSIDERING SIGNIFICANT STRENGTH OF RIDGE...PREFER THE ECMWF
 SOLUTION WHICH SPLITS THE SYSTEM TO THE NORTH AND SOUTH LEAVING
 NORCAL DRY...OR UNDER LIGHT PRECIP. EITHER WAY...COOLING IS IN
 STORE FOR NEXT TUESDAY UNDER INCREASED CLOUD COVER AND A COOLER
 AIRMASS. ALL SCENARIOS QUICKLY BUILD RIDGE BACK UP OVER THE WEST
 FOR A DRY PERIOD THROUGH THE REMAINDER OF THE EXTENDED PERIOD AND
 A RETURN TO ABOVE NORMAL DAYTIME HIGH TEMPERATURES. ANOTHER
 PACIFIC STORM SYSTEM IS FORECAST TO APPROACH THE COAST BY THE END
 OF NEXT WEEK BUT WITH STRONG HIGH PRESSURE FIRMLY IN PLACE OVER
 THE WEST IT IS LIKELY TO SEE THE SAME FATE AS THE TUESDAY SYSTEM.
 
 
 &&
 
 .AVIATION...
 
 HIGH PRESSURE CONTINUES OVER THE AREA WITH GENERAL VFR CONDITIONS.
 PATCHY IFR DUE TO FOG IN NORTHERN SAN JOAQUIN AND SOUTHERN
 SACRAMENTO VALLEYS THIS MORNING THROUGH ABOUT 18Z.  NORTH TO EAST
 WINDS 5 TO 15 MPH GUSTING TO 25 TO 30 MPH OVER SOME MOUNTAIN AREAS
 THIS MORNING. WINDS DECREASING THIS AFTERNOON BUT BREEZY EAST
 WINDS OVER RIDGETOPS AGAIN TONIGHT.
 
 
 &&
 
 .STO WATCHES/WARNINGS/ADVISORIES...
 NONE.
 &&
 
 $$

  NWS STO Office Area Forecast Discussion