Snow Storm #8: Preview

(updated below - Update II - Update III)

Wowser!

Storm 8 being loaded into the chamber with at least six weeks of winter to go! Could easily be 12+ contest-worthy storms this season...a NEWxSFC record.

Storm 8/s 'Call for Forecasts' may be issued SUN evening...if current model solutions and trends continue. Interesting event unfolding with a number of stations poised to measure wrap-around / comma head accumulations.

Long-wave amplitude forecast to increase rapidly along with shortening wave-lenght...but the flow regime is progressive. HPC decidedly cool to the idea in this afternoon/s 'Heavy snow / Icing' discussion of a winter storm for the east coast...but what do they know?

Today/s 12z NAM and GooFuS flock southern forecast stations beginning late in the day on MON and over most stations on into TUE.

A '2 to 3' hour earlier than usual 'deadline for entries' on MON is being considered to capture snowfall expected over southern forecast stations MON evening. Otherwise...the deadline would have to be SUN evening...which is a long 'a-double scribble' leadtime...given the main event looks to be TUE.

Image: MAR 1888 Blizzard...Newburgh...NY

UPDATE
02/01/00z progs are manna from heaven. NWP puts PHL underneath the crystal factory for 24-hours. Not that it/ll actually happen. Just saying.

UPDATE II
02/01/12z progs presenting quite a conundrum. NAM solutions still GO for Storm 8 even though the heaviest precipitation axis has shifted east.

GooFuS puts the storm several hundred miles farther east with no snow depicted for the east coast. 12z GooFuS a significant departure from its 00z and 06z solutions.

Will evaluate 18z runs and proceed from there. A 'Call for Forecasts' is still expected later today with the standard 10:30 PM deadline; although Contest #8 could be canceled on MON if 02/02/00z/12z model runs push the system well offshore.

Cancellation announcement...if required...will be made on the web log and StormVista...not via e-mail.

UPDATE III
18z runs of NAM and GFS in good agreement that Storm 8 will not happen TUE / WED.

VCP 32 - Call It A Single

Snow Storm #7: Results

Senior forecaster Donald Rosenfeld makes it two in a row having issued the best synoptic-scale forecast for NEWxSFC/s seventh snow storm. His 25 station forecasts verified with 56.4 SUMSQ error points (Z-Score = -1.318)...which was a 47% improvement over the average error of 106".

He hit the trifecta...placing first in Total Absolute Error and Average Absolute Error.
Total Absolute Error: 28" (29% better than average)
Average Absolute Error: 1.12" (29% better than average)

Donald Rosenfeld/s forecast had the lowest station errors @ PWM BDR ALB BGM MDT BWI and perfect forecast @ BDR.

Congratulations Donald Rosenfeld!

Donald Rosenfeld wins one FREE month of StormVista GOLD for his forecasting acumen.

2nd Place: skiGirl (57.7"; -1.283)
3rd Place: shanabe (60.6"; -1.205)
Honorable Mention: Raven (68.2"; -1.003)

Full forecast verification and results summary here.

Snow Storm #7: Preliminary Verification

Preliminary storm-total snowfalls for Tuesday and Wednesday from CDUS41...PNS...and CF6 bulletins.

Two new daily records.
BTV: 9.1" (5.3"; 1958)
BGM: 5.9" (5.1"; 2004)

HYA STP estimated from METAR 6-group data @ 10:1 in good agreement with vicinity reports carried in BOSPNS.

Please report errors in Remarks.
Final results and storm summary Friday evening.

Sudden Stratospheric Warming - Full On

Full-blown SSW underway with a reversal of the 10 mb wind extending below 60°N.

Broke through 50 and 70 mb...heading for 100.

Sudden Stratospheric Warming - Close @ Hand

Defined as a complete disruption / reversal of the polar vortex @ 60°N... a well-forecast MAJOR stratospheric warming appears close-at-hand.

The vortex has bifrucated @ 10 mb on JAN 24...30 mb on JAN 27...and is poised to reach 50 mb level in a few days.

The event gets a quick mention in WSI/s latest winter update...

""An incipient stratospheric warming event, which appears to be historic in magnitude, may continue to favor more Arctic air masses in mid-latitudes and increases confidence in the widespread cold forecast of the US these upcoming few months.""

Upper air plots courtesy Univeristy of Wyoming/s Department of Atmospheric Science





Wowzer!

Snow Storm #7: The Forecasts

14 forecasters...including 3 rookies...for the season/s seventh storm. Forecasters in the table above are ranked in ascending order by expected storm-total snowfall.

Station forecasts here.



Mid-Atlantic region gets a bone tossed its way. Best snows expected over northern stations...a season-long trend.



Teleconnections celebrating Opposite Day.



LOW pressure over Mississippi River on tonight/s surface chart expected to morph into...

Snow Storm #7: Raw Forecasts

Here.

13 entries...including 11 veterans and 2 rookies.

Formatted forecasts will be available at the Contest web site early tomorrow evening.

Overview and some summary charts will go up on the web blog around the same time...too.

WSI - JAN Update - Winter '08 / '09

NE...
Feb - colder than normal
March - colder than normal
April - colder than normal

""The general pattern of cold-north and warm-south observed during the winter so far will generally continue into early spring. The warmest temperatures, relative to normal, will be in the south-central and southeastern states while the coldest temperatures will continue to be observed in the north-central states.

"The cold Pacific Ocean suggests that the upcoming aggregate three-month period will be relatively cold nationwide, relative to normal, especially in March and April.

"An incipient stratospheric warming event, which appears to be historic in magnitude, may continue to favor more Arctic air masses in mid-latitudes and increases confidence in the widespread cold forecast of the US these upcoming few months.""

(updated to include full forecast discussion)

Full press release here.

Snow Storm #7: Call for Forecasts

Large-scale...two-day event expected over the forecast area on Tuesday and Wednesday as the long-wave trof currently over the west coast comes east.

HPC discounted today/s 12z solutions for widespread heavy snow from GooFuS as an outlier; however...long-range NWP models have been flip-flopping for days on the evolution of the western trof...so here/s hoping they/ve missed the boat.

Deadline: 10:30 PM EST Monday...26 January 2009

Forecast element: storm-total snowfall
Verification begins: 12:01 AM EST Tuesday...27 January 2009
Verification ends: 11:59 PM EST Wednesday...28 January 2009

Enter your forecast here.
Follow the link from 'Enter Storm Forecast.'

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Details here.

More prizes will be awarded at the end of winter for the best over-all forecaster.
Details here.

As always...there/s no cost...or fee...or annoying requests for personal information to enter.

If you are making your first forecast this year or you entered the 'season-total' forecast contest...you/ll need to create an account (user name / password / valid e-mail...if you want a copy of your forecast sent to your Inbox) before entering a forecast.

Image: Niagra Falls 2/9/1908