Cold snow Storm Cali likely 14-17 Mon-Thur

[donbrown]

The high pressure just off San francisco should dissipate the next few days causing the jet stream to shift over Xalifornia and drag some Hawaii moisture our way mixed with the cold jet stream.

Not sure of snow altitude levels or amounts but it is gonna snow for at least 24 hours 14-17 February.

Will post when I know more

 

[tudizzle]

Bring it!

I happen to show up on the 17th just in time for some of that Cali Pow!


same time last year near Sonora....

 

[skibreeze]

Bring it!

 

[donbrown]

PRECIPITATION-WISE...THE FOCUS WILL BE ACROSS THE PACIFIC
NORTHWEST AS A COUPLE COLD FRONTS MOVE INTO THE REGION...AND FOR
THE MOST PART...WHERE CYCLONIC ONSHORE FLOW PERSISTS THROUGHOUT
THE MEDIUM RANGE PERIOD. LIQUID EQUIVALENT AMOUNTS OF 3 TO 5
INCHES ARE POSSIBLE HERE THROUGH THE PERIOD...WITH LOCAL AMOUNTS
OF 8 INCHES POSSIBLE.

The above is from NOAA http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html
But are they talking WA and Oregon?



California station is saying a big MAYBE ...15-18 Feb

OVER THE NEXT SEVERAL DAYS, THE RIDGE WILL REMAIN IN PLACE WITH SOME SLOW WARMING THROUGH THE WEEKEND. BY EARLY NEXT WEEK THE FORECAST MODELS (YOU GUESSED IT) TRY AND BREAK DOWN THE RIDGE AND PUSH A TROUGH OF LOW PRESSURE INTO AND THROUGH THE AREA MONDAY NIGHT AND TUESDAY. I HAVE RAISED POPS TO THE CHANCE CATEGORY FOR THIS TIME FRAME HOWEVER CONFIDENCE IS NOT THAT HIGH THAT THE BREAK THROUGH WILL OCCUR PER THIS MODEL RUN.

 

[donbrown]

Today saying change is MOST likely but not sure of the amount of moisture.

MEDIUM RANGE MODELS ARE STILL SHOWING A SHIFT IN THE LONGWAVE
PATTERN OVER THE EAST PAC AND NOAM WITH TIME. THIS INVOLVES THE
WEAKENING OF A STRONG UPPER LOW OVER HUDSON BAY CANADA...WHICH
BRINGS COLD AND SNOW TO MUCH OF THE EASTERN US...AND THE DEMISE OF
A PERSISTENT LONGWAVE RIDGE OFF THE WEST COAST KEEPING CA DRY.


THIS SHIFT IN THE PATTERN WILL BRING THE FIRST IN A SERIES OF
TROFS INTO THE PAC NW THIS WEEKEND. AS THE RIDGE OVER CA SHIFTS
EAST...THE RESULTING QUASI ZONAL FLOW WILL BRING INCREASING
CHANCES OF PRECIP TO CENTRAL CA AS EARLY AS MON NITE OR
TUES...WITH MORE SHORTWAVE ENERGY FOLLOWING THE NEXT 2 DAYS AT
LEAST. WHETHER THIS PATTERN SHIFT IS/OR WILL BE A PERMANENT
CHANGE...OR JUST TEMPORARY...IS UNKNOWN. BUT CONFIDENCE IS
BETTER THAN AVERAGE FOR SOME FORM OF CHANGE DAYS 5 AND BEYOND.

 

[donbrown]

Mammoth saying snow likely ... amounts not stated ... yet to 6000-7000 feet.

So snow fall could begin any time after Midnight Monday night. 500ht Heights are around 552dm at that time, so a snow level around 6000 to 7000 feet to begin with seems good depending upon the dew point and 700mb temps. The nature of the moisture is subtropical so it may end up a bit higher to start with. At the moment…..the isentropic surface along with the front slide through Southern Mono during the afternoon Wednesday. With some additional energy coming through Wednesday night.

A following shot of energy comes off Japan about the morning of the 14th. Although it really does not spin up for another day. Will watch that one the next couple of days….

 

[BossRev]

I'm with Diz and Skib......

BRING IT!!

 

[donbrown]

Two weather forecast computer models.

One says starts storming Monday trhe other says Tuesday.

BOTH models say storm will last to at least Thursday, and will be in waves.

Warm at first then getting cooler to 6000 feet.

So snow more likely dates 15-17 of February.

If this happens ... more storms to come.

THIS SHIFT IN THE PATTERN WILL BRING THE FIRST IN A SERIES OF
TROUGHS INTO THE PACIFIC NORTHWEST THIS WEEKEND. THE RIDGE OVER
CALIFORNIA WILL SHIFT EAST BY MONDAY...OPENING THE DOOR TO A
TROUGH DROPPING OUT OF THE GULF OF ALASKA. THIS WILL WILL BRING
INCREASING CHANCES OF PRECIPITATION TO CENTRAL CALIFORNIA. THE
GFS BRINGS THE PRECIPITATION AS EARLY AS MONDAY NIGHT WHILE THE
ECMWF HOLDS IT OFF UNTIL TUESDAY. BOTH MODELS INDICATE MORE
SHORTWAVE ENERGY FOLLOWING WEDNESDAY AND THURSDAY AND POSSIBLY
LONGER.

 

[donbrown]

Storm very likely late Monday to Thursday and likely into Sunday !

Noone is saying depth amount.

Lows Tuesday at 7000 feet in the 20's
Wednesday lows in the teens
High temp Thursday 32 @ 7000 feet

Percent chance of rain/snow Tuesday Wednesday Thursday

Los Angeles 20% 60 20

Sequoias 40 70 30

Mammoth 50 90 50

Truckee 50 90 50

CONFIDENCE IS INCREASING IN A SHIFT TO A WETTER PATTERN FOR
CENTRAL CALIFORNIA NEXT WEEK. THE UPPER RIDGE WILL BE FLATTENED
A BIT AND CONTINUE SHIFT EAST SUNDAY AS A SHORTWAVE MOVES ACROSS
THE PACIFIC NORTHWEST. THEN A TROUGH DROPS OUT OF THE GULF OF
ALASKA MONDAY...WITH PRECIPITATION SPREADING INTO CENTRAL
CALIFORNIA BY MONDAY EVENING. A LONGWAVE TROUGH ESTABLISHES ITSELF
ALONG THE WEST COAST WITH ADDITIONAL SHORTWAVE IMPULSES ROTATING
THROUGH IT. THIS WILL CONTINUE THE CHANCE OF PRECIPITATION OVER
THE REGION THROUGH AT LEAST THURSDAY...AND POSSIBLY INTO NEXT
WEEKEND. AFTERNOON HIGH TEMPERATURES WILL DROP BACK TO A FEW
DEGREES BELOW SEASONAL AVERAGES DURING THE PERIOD...WHILE THE
CHILLY OVERNIGHT LOWS WILL WARM A FEW DEGREES WITH THE INCREASING
CLOUDS AND PRECIPITATION.

 

[donbrown]

STARTING wEDNESDAY

Northern Sierra (Tulare county north) snow levels 3000 feet

Kern County south 4500 feet

TROUGHS BUT THEY GENERALLY BRING THE COLDER AIR IN BY
WEDNESDAY NIGHT...LOWERING SNOW LEVELS TO AROUND 3000 FT IN THE
NORTHERN PORTIONS OF THE SIERRA ZONES AND AROUND 4500 FT IN THE
MOUNTAINS OF KERN COUNTY. AFTERNOON HIGHS WILL BE A FEW TO SEVERAL
DEGREES ABOVE CLIMO THROUGH MONDAY...THEN DROPPING BELOW SEASONAL
AVERAGES THROUGH THE END OF THE WEEK.

 

[donbrown]

No snow amount predictions ... yet.

Now say storm on and off Monday thru Friday most of it Wednesday-Thursday.


Local Mammoth forecaster taking WILD guess and saying 2.5 tot acc at lodge.

 

[donbrown]

Now saying storm Mon-Friday AND MAYBE A COUPLE MORE DAYS.

Snow levels revised to 5000 feet.

No snow amount calculations

Still think Wed-Thur bulk of the storm for snow fall.

 

[donbrown]

Can see low pressure system off Washington 12feb 302am pst. Low brings the cold and wet to an area.

All forecasting models still say storm Mon thru Thurs with most moisture WED-THURS... and then not sure.

One computer says stops on Friday and snow levels to 5000 feet. Other model says Storm thru weekend into Monday 14-21 Feb with levels to 2000-3000 feet.

This picture updates at least daily ... see date/time on pic

 

[donbrown]

Truckee at 90% for storm late Tuesday- early Thursday ... esp WED

Mammoth at 70%

Kern County at 50%

Los Angeles at 60%

(50 for Kern and 60 for LA is not a typo)

 

[donbrown]

Rain Tuesday 7000 feet ... Then snow to 5000 feet thru Thursday.

Mammoth expects 3 inches rain and 2.5-3.5 feert snow.

Another storm Friday - Saturday ... a warm one but coming from the south not north so might only get to Kern/Tulare County.

Don

...

By Tuesday night the tempo will pick up with moderate snowfall a possibility then heavy snow likely Wednesday and a good part of Wednesday night. This is because that although the cold polar front is expected to come through during the afternoon, several trailing vort maxes along with the upper flow natural to the Sierra should keep an active pattern going into the night. It looks like a good 3 feet possible on the plot by Thursday AM with the possibly of more snow over the Crest. Currently…HPC is forecasting about 3.00 inches over our area by Thursday AM. Considering how cold the storm is in back of the front with several inches of snow falling post frontal….we should easily get 3 feet plus by Thursday AM. The Dweebs will be updating the QPF on a daily bases…

Thereafter…..another system may effect the Sierra by Friday, however the upper jet by then favors more Southern California then Mammoth Lakes. It may be that we will just be an a cold showery pattern.

 

[donbrown]

NORTH OF KERN County ... MAMMOTH / Mono to Lassen

1-2 FEET ABOVE 7000 FEET MONO TO LASSEN COUNTY

Mammoth forecaster thinks 3 feet by thursday at ther lodge

High winds monday

Next storm Thursday which will likely be from Fresno south

2-3 inches rain from fresno to LA 17-19 Feb

FOR SUNDAY...MILD TEMPERATURES WILL STICK AROUND AND BE SIMILAR TO
YESTERDAY WITH LOWER VALLEYS IN THE MID TO UPPER 60S AND SIERRA
LOCATIONS IN THE 50S. WINDS HAVE BEGUN TO DECREASE SLIGHTLY THIS
MORNING...ALLOWING THE LAKE WIND ADVISORY AT LAKE TAHOE TO BE
CANCELLED. THIS BREAK IN THE WINDS...WITH WIND GUSTS BETWEEN 35 AND
50 MPH ALONG THE RIDGES...WILL NOT STICK AROUND VERY LONG AS THE
TROUGH DIGS SOUTHWARD TONIGHT.

FOR MONDAY...WINDS WILL INCREASE ALONG THE RIDGES INITIALLY BRINGING
50 TO 60KT 700MB FLOW TO THE REGION BY 12Z MONDAY. NAM BUFKIT
SOUNDING STILL SHOWING A CRITICAL LAYER MONDAY MORNING WHICH WILL
PROVIDE THE MECHANISM FOR A SIGNIFICANT DOWNSLOPE WIND EVENT
AFFECTING RENO AND SOUTHWARD ALONG THE HIGHWAY 395 CORRIDOR. MONDAY WIND
GUSTS ALONG THE RIDGES...ESPECIALLY IN THE TAHOE AND MONO...COULD
REACH BETWEEN 85 AND 100 MPH AT TIMES. HIGH CONFIDENCE REMAINS FOR
PERSISTENT AND WIDESPREAD ADVISORY LEVEL WINDS WITH THE POTENTIAL
FOR HIGHER WIND GUSTS IN WIND PRONE LOCATIONS THROUGH TUESDAY NIGHT.
THE HIGH WIND WATCH IS STILL IN PLACE OVER THE ENTIRE AREA FOR
MONDAY AND TUESDAY. DECIDED TO LEAVE BREAKING UP REGION INTO MORE
SPECIFIC WIND STATEMENTS FOR THE FOLLOWING SHIFT. KEPT IN BLOWING
DUST FOR THE LOWER VALLEYS SINCE MOST OF THOSE LOCATIONS HAVE NOT
HAD MUCH RAIN SINCE THE BEGINNING OF THE YEAR.

MOST PRECIPITATION WILL REMAIN CONFINED ALONG THE IMMEDIATE CREST
WITH SOME CHANCES FOR PRECIPITATION TO THE FAR NORTHERN CWA. TUESDAY
EVENING AS THE COLD FRONT APPROACHES... CHANCES FOR PRECIPITATION
WILL INCREASE ALONG THE NORTHWEST PORTION OF THE CWA. EXPECT THE
HEAVIEST QPF AND SNOW AMOUNTS TO REMAIN ALONG THE RIDGES IN THE
TAHOE BASIN AND NORTHWARD INTO PLUMAS AND WESTERN LASSEN COUNTY FOR
TUESDAY NIGHT. SNOW LEVELS WILL BEGIN TO FALL RAPIDLY IN THESE AREAS
WHICH WILL ALLOW FOR SOME SNOW TO BEGIN AFFECTING HIGHER SIERRA
PASSES. LINDAMAN

.LONG TERM...WEDNESDAY THROUGH SATURDAY...

NO MAJOR CHANGES IN THE EXTENDED FORECAST WITH MODELS IN GOOD
AGREEMENT WITH THE EVOLUTION OF THE LONGWAVE PATTERN THROUGH NEXT
WEEK. STRONG COLD FRONT WILL PUSH THROUGH THE REGION ON WEDNESDAY
WITH WIDESPREAD SNOW ON WEDNESDAY AND COLD TEMPS THE REST OF THE
WEEK.

SNOWFALL WILL CONTINUE INTO WEDNESDAY MORNING AS THE JET PUSHES
SOUTH ALONG THE SIERRA...WITH SPILLOVER INCREASING EARLY WEDNESDAY
MORNING AS THE COLD FRONT PUSHES DOWN. INCREASING INSTABILITY WILL
HELP GET THE SPILLOVER INTO WESTERN NV...WITH SOME SNOW ACCUMULATION
POSSIBLE WEDNESDAY AS SNOW LEVELS CRASH DOWN BEHIND THE COLD FRONT.
STRONG FRONTOGENESIS COULD CAUSE A FEW HOURS OF SNOW ACCUMULATION
INTO THE LOWER VALLEYS ON WEDNESDAY...EVEN MORE IF IT COMES THROUGH
THE AREA WEDNESDAY MORNING. WILL HAVE TO KEEP A CLOSE EYE ON THE
TIMING AND DURATION OF THE LOW LEVEL FORCING WITH REGARD TO SNOW
AMOUNTS IN THE DESERT VALLEYS.
AS FOR THE SIERRA...WEDNESDAY WILL BE A DAY OF CONTINUOUS MODERATE
TO HEAVY SNOWFALL...WITH SNOWFALL RATES OF UP TO 2-3 INCHES PER HOUR
AT TIMES. STORM TOTAL SNOWFALL IN THE EASTERN SIERRA OF WESTERN
LASSEN COUNTY...EASTERN PLUMAS COUNTY...THE LAKE TAHOE BASIN AND
MONO COUNTY WILL END UP BETWEEN 1 TO 2 FEET WITH HIGHER AMOUNTS
POSSIBLE ALONG THE SIERRA CREST. MODELS HAVE BEEN REALLY CONSISTENT
WITH THE OVERALL QPF/SNOW AMOUNTS...BUT DETAILS OF THE SNOW TOTALS
WILL GET IRONED OUT IN THE NEXT COUPLE DAYS. HEAVY SNOWFALL WILL
LIKELY CREATE DELAYS AND/OR ROAD CLOSURES IN THE SIERRA ESPECIALLY
TUESDAY NIGHT THROUGH WEDNESDAY. WINTER STORM WATCH MAY NEED TO BE
ISSUED LATER TODAY.

ANOTHER UPPER LOW LOOKS TO AFFECT THE REGION AS WE GO INTO NEXT
WEEKEND...BUT MODELS ARE INCONSISTENT WITH THE TIMING. THIS WOULD
BRING ANOTHER PERIOD OF SNOW TO THE SIERRA AND WESTERN NV SOUTH OF
I-80. CONTINUED TO TREND POPS UPWARD FOR THIS SECOND SYSTEM AS
MODELS REMAIN CONSISTENT WITH THE OVERALL IDEA...ALTHOUGH TIMING IS
AT VERY LOW CONFIDENCE BEYOND THURSDAY. WITH THE LONGWAVE TROUGH
SETTLING INTO THE WESTERN STATES THROUGH NEXT WEEKEND...COLD
TEMPERATURES WILL CONTINUE ALONG WITH MOSTLY CLOUDY SKIES AND PERIOD
OF SNOW SHOWERS UNDERNEATH THE COLD POOL ALOFT. HOON

 

[donbrown]

http://wxweb.meteostar.com/models/noaaport_loop.php?PATH=/var/www/leads_images/satellite/EP1/IR/&NUMBLOOP=10

 

[donbrown]

Truckee at 100 % likely to get snow Wednesday.

Mammoth at 90%

Isabella at 80%

Mon-Tues light rain with severe winds up to 100 MPH gusts.

Then snow storm .. WED-THURS about 3 inches water so now they say 3-4 feet of snow Mammoth to Truckee at 8000 feet. 14-17 feb

Next storm Friday Saturday may only hit SOCAL with 1-3 inches rain. Levels to 4000 feet. 18-19 feb

FORCASTING MORE STORMS 21-26 feb but forecasters are unsure of the accurACY. So stay tuned.


Mammoth forecaster ... THE DWEEB

It will not be until Wednesday for the Moderate to Heavy snowfall. The cold front will probably come through early afternoon. Snowfall rates will increase to 2 to 3 inches per hour during the afternoon. HPC has a 2.84 bulls-eye near Yosemite for the 48 hours period between 4:00am Wednesday and 4:00am Friday. Although it appears that the lions share of precipitation of this storm will be up in Northern California, Mammoth Mountain could pick up as much as 3 feet by Thursday. The snow will be Cold and Powdery from Wednesday afternoon through the following several days. Ratios will begin about 10:1 then increase to 15:1 to as high as 20:1 by Wednesday night.

 

[BossRev]

That's music to my ears..