Watch out West Coast!!!!

[aveosmth]

This is from the SFO NWS....

THE PROSPECTIVE THU STORM USHERS IN A PERIOD OF WHAT COULD BE VERY
INTERESTING AND WILD WX FOR THE ENTIRE W COAST IF THE GFS AND EURO
VERIFY WELL. THE BASIC PATTERN SETUP IS A VERY STRONG UPPER RIDGE IN
THE GULF OF AK...THE EURO AND GFS HAVE A 582 DM 500 MB RIDGE OVER THE
ALEUTIANS ON THU. THIS IS AN UNUSUALLY HIGH 500 MB HEIGHT FOR OUR
REGION IN JAN MUCH LESS THE ALEUTIANS. ON THE E SIDE OF THE RIDGE IS
A VERY STRONG NLY JET DROPPING CLEAR FROM THE ARCTIC OCEAN THRU WRN
CANADA. THIS IS THE IDEAL PATTERN. TO TRANSPORT ARCTIC AIR INTO THE
PACIFIC NW. SOME IS ALREADY TRICKLING INTO WRN WA. STARTING WITH THE
THU SYSTEM THE PREVAILING PATTERN IS TO SET UP A COLD UPPER LOW AT
THE SRN EXTENT OF THE NLY JET WITH THE LOW CENTER OVER OR JUST S OF
THE PACNW. THIS WOULD ALLOW THE ARCTIC TO PENETRATE UNUSUALLY FAR TO
THE S AND W...AT LEAST AS FAR AS W CNTRL OR. USUALLY A STRONG WLY
JET THEN CONSOLIDATES UNDER THE UPPER LOW AS THE GFS IS FORECASTING
ON THU.

THE NOTABLE THING IS THAT THE GFS THEN KEEPS THIS PATTERN IN PLACE
FOR ABOUT A WEEK. EARLY IN THAT PERIOD MODELS LIKE THE EURO AND
DGEX BASICALLY AGREE. THIS PATTERN IS CAPABLE OF PRODUCING A
SERIOUS SHOT OF WINTER WX IN THE PACIFIC NW WITH COLD...SNOWY
CONDITIONS EVEN ON THE W SIDE OF THE CASCADES. UNDER THIS SCENARIO
CA GETS SOAKED...ESPECIALLY THE CNTRL AND SRN PARTS OF THE STATE...
WHILE FAR NRN CA COULD GET SNOW DOWN TO VERY LOW ELEVATIONS. THIS IS
A RARE PATTERN. THE MRNG DISCUSSION FROM PDX MENTIONED THAT NCEP IS
COMPARING THE PROSPECTIVE SETUP TO JAN 1950...WHICH SAW RECORD COLD
WX IN PDX ALONG WITH LOTS OF SNOW (41.4 INCHES FOR THAT MONTH). I
DONT GO BACK THAT FAR BUT I RODE OUT SUCH A PATTERN IN PDX IN JAN
1969. PDX AND SEA HAD HEAVY SNOW (45.4 INCHES FOR THE MONTH AT SEA-
TAC AIRPORT) AND A LONG PERIOD OF SUBFREEZING TEMPS. THE SNOW DEPTH
AT SPOKANE REACHED 47 INCHES! CA SAW TORRENTIAL RAIN...ESPECIALLY IN
THE S. LOS ANGELES RECORDED 14.94 INCHES FOR JAN 1969...MOST OR ALL
OF IT IN THE LAST HALF OF THE MONTH. MANY...MANY FEET OF SNOW FELL
IN THE SIERRA. A PERIOD OF WX WITH THESE CHARACTERISTICS UP AND DOWN
THE COAST ONLY OCCURS ABOUT ONCE EVERY DECADE OR TWO...IN FACT THE
SNOW TOTAL AT SEA-TAC AND THE RAIN TOTAL AT LA HAVE NEVER BEEN
MATCHED OR EXCEEDED IN ANY MONTH SINCE THEN. SO THINGS WILL PROBABLY
TURN OUT TO BE MORE BENIGN THAN THE ABOVE SCENARIO...BUT IT WILL BE
INTERESTING TO SEE WHAT HAPPENS.

We have already met our yearly rainfall totals here in Los Angeles so this is very concerning....

[R-Dub]

Thanks for catching that aveosmth! Very interesting, and its looking more and more like we are going to get hammered here in the Pac northwest, and all along the west coast!

[aveosmth]

No problem R-Dub! I may be flying in to Sea-Tac on the 9th so this may be a major, major problem....even PDX will probably be affected as well.....

[Brent]

We have already met our yearly rainfall totals here in Los Angeles so this is very concerning....

With 362 days left in the year?

[R-Dub]

AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SEATTLE WA 844 PM PST MON JAN 3 2005

.SYNOPSIS...COOL AND DRY NORTHEAST FLOW WILL CONTINUE OVER WESTERN WASHINGTON THROUGH WEDNESDAY...MAINTAINING CLEAR WEATHER. A COLD FRONT WILL MOVE SOUTH ACROSS THE AREA THURSDAY AFTERNOON USHERING IN MODIFIED ARCTIC AIR AND AN UNSETTLED PERIOD THAT SHOULD LAST THROUGH THE WEEKEND. && .

DISCUSSION... STRATUS PERSISTED OVER THE LAND AREAS OF THE STRAIT DUE TO LOW LEVEL UPSLOPE FLOW. THIS FLOW HAD AN OVER WATER TRAJECTORY THAT WAS SUFFICIENT ENOUGH TO PRODUCE THE CLOUD LAYER. DO NOT FORESEE MUCH CHANGE OVERNIGHT...THUS UPDATED THE FORECAST FOR THIS ZONE TO SHOW MORE CLOUDINESS. ALSO UPDATED THE CASCADE ZONES TO MENTION LOW CLOUDS AND FREEZING FOG IN THE PASSES DUE TO ELY UPSLOPE FLOW. MEANWHILE...A BLOCKING UPPER RIDGE OFFSHORE WILL RESULT IN CONTINUED DRY...NLY FLOW OVER THE AREA. EXPECT THE FLOW ALOFT TO BECOME MORE ELY ON WED AS THE RIDGE AXIS BECOMES E-W ORIENTED OVER CANADA.

THEN A LOW PRES SYSTEM EMANATING FROM NEAR THE GULF OF AK IS EXPECTED TO DIVE TOWARD THE AREA ON THU WITH RAIN OR SNOW DEVELOPING THU AFTERNOON. THIS SYSTEM BEARS WATCHING AS IT HAS THE POTENTIAL TO PRODUCE SIGNIFICANT SNOWFALL ACROSS MUCH OF THE LOWLANDS THU NIGHT.

CURRENT FORECAST LOOKS FINE...NO UPDATES PLANNED.

[weatherlover427]

We have already met our yearly rainfall totals here in Los Angeles so this is very concerning....

With 362 days left in the year?

Remember they also measure the rain totals from July 1st to June 30th ... Aveosmth means THOSE ones were the ones already met. We are barely halfway through that one (known as the water year) and there is still quite a ways to go.

Check this out:



Note how the red underlined line says "Since Jan 1". You'll note that, in that line, there is a number that reads 2.48. This number means that we were 2.48 inches of rain above normal for all of last year.