Wednesday, December 31, 2008

New Year/s Eve Snow Storm

(updated below)

Snowfall was fairly intense there for a while this afternoon...with some northeastern stations reporting rates up to 2" / hour.

At times...VSBYs went below 0.25 SM beneath 100' ceilings. Network warning radars observed widespread banding signatures south of the mid-level deformation zone.

Cold columns and an energetic short wave made for extremely high SN:H2O (ALB @ 46:1...BGM @ 31:1...and BDR @ 17:1).

Turned out to be a marginal contest storm with the majority of stations reporting little more than nuisance amounts...although spotter reports from MA and NH were notably greater. Map shows preliminary snowfall reports from CDUS41 and PNS bulletins at post time.

UPDATE:
ALB - 7.2"; 55:1
BOS - 6.5"; 16:1
ORH - 6.4"; 16:1
BDL - 4.9"; 16:1
CON - 3.8"; 17:1
PVD - 4.9"; 19:1
CON - 3.8"; 17:1

New daily records @ BDL...BDR...BOS...ORH...and PVD.

In hindsight...this storm was probably contest-worthy.

Thursday, December 25, 2008

Interim Standings

After three snow storms...Emoran holds a slim 0.027 margin over donsutherland1 with dmcguriman in third.

Under the ‘two-thirds’ rule…forecasters who have entered at least two forecasts are included in this interim summary.

Full forecaster statistics table and charts here.

SUMSQ errors for each contest snow storm are normalized with a 'Z-score'...then averaged to compute the standings. Forecasters who have entered at least 2/3 of all snow storm contests are included in the standings.

If a forecaster has participated in more than two-thirds of all snow storm contests...then Z-scores from their 'best two-thirds' forecasts are used to calculate Interim and Final standings. Same idea as dropping the lowest quiz score before the final grade is computed.

Wednesday, December 24, 2008

Snow Storm #3: Results

Senior forecaster emoran made the best synoptic-scale forecast for NEWxSFC/s third snow storm. His forecast verified with 79.2 SUMSQ error points (Z-Score = -1.013).

He completed the trifecta with lowest Total Absolute Error (25.45") and Average Absolute Error (1.21"). His 90.2% R-SQ score...a measure of how well a forecast captures the variability of the observed snowfall... was also ranked first.

Emoran had the lowest station errors @ CAR BTV BDL MDT PHL BWI and made perfect forecasts @ BDL PHL BWI.

Congratulations emoran!

Emoran wins one FREE month of StormVista GOLD for his efforts.

2nd Place: donsutherland1 (90.8"; -0.880)
3rd Place: Raven (101.5"; -0.758)

Three forecasters came within 5% of the 97.7" " storm-total snowfall.

Full forecast verification and results summary here.

Tuesday, December 23, 2008

Snow Storm #3 - Coastal Frontogenesis


Click image to animate.

Note the sharp temperature gradient between PWM and Buoy 44005. The buoy is located 78 NM east of PWM.



Rapid deepening of -2.7 mb / hr at 00z concurrent with strongest horizontal temperature gradient of 0.372°F / NM. Strong temperature gradients initiate ageostrophic circulations across the boundary leading to pressure falls and upward vertical motion.

PWM observed a record 14.5" snowfall from this storm. The old record of 12.4" was set in 1933. Snow totals are often suppressed at PWM b/c of its proximity to the coast; however...in this case...the station remained on the cold side of the coastal front and all precipitation fell as snow.

WSI - DEC Update - Winter '08 / '09

From Reuters UK...
""Most of the East should be quite mild in January, before the pattern shifts again in February and March to allow for below-normal temperatures to return to the Northeast," WSI forecaster Todd Crawford said.

"Although February and March are expected to be colder than normal on average, the Northeast will experience greater temperature fluctuations than other regions, WSI said.

[...]

""Current oceanic and atmospheric indicators are quite similar to those observed during the winters of the early 1960s, when cold western U.S. winters were commonplace," Crawford said."
NE CONUS (relative to normal)
JAN - warmer
FEB - colder (except NJ/DE/MD)
MAR - colder

Snow Storm #3: Preliminary Verification

Preliminary storm-total snowfalls from CDUS41...PNS...and CF6 bulletins for Sunday and Monday.

Seven new daily records were set on Sunday.
PWM - 14.5" (12.4"; '33)
CON - 10" (7.9"; '14)
BGR - 9.7" (7"; '95)
BTV - 9.1" (7.8"; '10)
ORH - 8" (6"; '54)
ALB - 6.6" (5.7"; 1887)
BDL - 5" (2.6"; '75)

SN:H2O @ PWM and CON estimates derived from METAR 6///// and P///// groups.

Please report errors in Remarks.
Final results and storm summary Wednesday.

Monday, December 22, 2008

Snow Storm #2: Results


Journeyman forecaster Bruced39 made the best synoptic-scale forecast for NEWxSFC/s second snow storm. His forecast verified with 112.6 SUMSQ error points (Z-Score = -1.318). His 81.3% R-SQ score was also ranked first.

Bruced39 had the lowest station errors @ PWM BTV PVD BDR.

Congratulations bruced39!

Bruced39 wins one FREE month of StormVista GOLD for his efforts.

2nd Place: donsutherland1 (123.9"; -1.199)
3rd Place: emoran (125.9"; -1.179)

Five forecasters came within 5% of the 119.85" storm-total snowfall. Not only does the forecast need to get the storm-total snowfall right...but it has to be put in all the right places.

Intern / Rookie class: First-time forecaster Anthony placed first.

Full forecast verification and results summary here.

Sunday, December 21, 2008

Snow Storm #3: The Forecasts



11 forecasters for this week/s third snow storm. One additional entry than reported last night b/c our server delayed transmission of a timely entry. Never before has there been so many contest-worthy storms at one time.

Station forecasts here.



Bonus snows expected over northern forecast stations with respectable amounts farther south.



NAO and PNA closer to normal...but AO flying high near outlier territory.



Verification began last night @ midnight. Snowfall continues over the forecast area at post time and is expected to continue into Monday afternoon. Preliminary storm-total snowfalls will be posted early Tuesday with the final results available on the web site Wednesday.

Snow Storm #2: Preliminary Verification

Preliminary storm-total snowfalls from CDUS41...PNS...and CF6 bulletins for Friday and Saturday.

Five new daily records were set on Friday.
ORH - 11.6" (10"; '45)
BTV - 8.6" (5.2"; '96)
ALB - 7.8" (4.2"; '86)
PWM - 6.5" (4"; '61,'45,1885)
CON - 6.5" (5"; '85)

SN:H20 @ HYA...ABE...EWR are estimates derived from METAR 6///// and P///// groups.

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

Friday, December 19, 2008

Snowfall Expected for Most of Shijiazhuang This Weekend

From the Handan Daily...
At 17 o’clock yesterday, provincial weather services in Shijiazhuang released warning of the coming strong winds and cold weather. The experts from the provincial weather services indicated that at the end of this weekend, the weather in the whole province will change into cloudiness from the cold winds and most of the areas will have snowfall.

Call for Forecasts: Snow Storm #3 - Winter '08 / '09

Don/t put those shovels and snow blowers away quite yet. More inventory on the way.

The third snow storm in less than a week is expected to affect the forecast area beginning Sunday. This one will approach from a lower latitude and undergo approximately 12+ hours of rapid deepening off the upper mid-Atlantic and southern New England coast. A moderately strong arctic HIGH progged to hold its position north of the LOW throughout the event...locking in lo-level cold air. Aloft...a more potent upper LOW with a forecast 100+ kt jet max at the base of the trof...will enhance the system/s dynamics and storm-total snowfall potential.

Make the best forecast and you/ll win one month of FREE access to StormVista GOLD. Details here.

Deadline: Saturday...20 December...2008 @ 10:30 PM EST

Forecast element: storm-total snowfall
Verification period begins: 12:01 AM EST Sunday...21 December 2008

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

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...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.

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The Northeast Weather Snowfall Forecast Contest (NEWxSFC) is celebrating its 10th anniversary this winter. The Contest began during the '99/'00 season on USENET/s ne.weather news-group. It/s the longest...continuously held snowfall forecasting contest for the NE CONUS on the Internet.

The Contest is open to any and all of the following:
Amateur and professional forecasters; broadcasters with or without trained Seals; weather-biz types and wanna-bees; wish-casters...astrologers...and other class of dreamers; Pollyannas or Cassandras; registered Nostradamusts; non-violent megalomaniacs; woolly-bear caterpillars or their agents; pest detectives...NE.Wx Usenet NG or GoogleGroup regulars and lurkers...refugees from EUSWx...StormVista...Golden Snowball...and meteorologists.

What is a contest-worthy event?

Snow Storm #2: The Forecasts



18 forecasters...including 2 new Rookies. Moderate snow occurring early this evening and more on the way this weekend.

Station forecasts here.



Forecaster consensus for a wide-spread New England event with heavy snowfalls expected at many stations.



What/s up with that CW about 'needing' -NAO...-AO...+PNA for a significant snow storm?



Verification began last night @ midnight. Snowfall continues over the forecast area at post time and is expected to continue into Saturday afternoon. Preliminary storm-total snowfalls will be posted early Sunday with the final results available on the web site Monday evening.

Thursday, December 18, 2008

Snow Storm #1: Results

Wxduff made the best synoptic-scale forecast for NEWxSFC/s inaugural snow storm. His forecast verified with 10.3 SUMSQ error points (Z-Score = -1.106).

He hit the trifecta with 1st place finishes for Total Absolute Error (9.05") and Average Absolute Error (0.57"). His 86.3% R-SQ score was second-highest of all entries.

Wxduff made perfect forecasts @ CON HYA EWR and had the lowest errors @ BGR PWM CON HYA EWR.

Congratulations Wxduff!

Wxduff wins one FREE month of StormVista/s GOLD for his efforts.

2nd Place: donsutherland1 (14.4"; -0.939)
3rd Place: dmcguriman (19.4"; -0.675)

Rookie forecaster 'weatherT' came within 0.7" of the 26.7" storm-total snowfall.

Full forecast verification and contest summary here.

Snow Storm #1: Preliminary Verification

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

No new daily records were set.

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

Call for Forecasts: Snow Storm #2 - Winter '08 / '09

Round 2! After a slow start...we/re off the races.

Good prospects for a good dump as a second...stronger wave cruises into the forecast area on Friday for Snow Storm #2. Progs continue the idea of enhanced omega from coupled jet structure and strong...lo-level forcing courtesy warm-air advection.

Make the best forecast and you/ll win one month of FREE access to StormVista GOLD. Details here.

Deadline: Thursday...18 December...2008 @ 10:30 PM EST

Forecast element: storm-total snowfall
Verification period begins: 12:01 AM EST Friday...19 December 2008

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

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...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.

------------------------------------------------------

The Northeast Weather Snowfall Forecast Contest (NEWxSFC) is celebrating its 10th anniversary this winter. The Contest began during the '99/'00 season on USENET/s ne.weather news-group. It/s the longest...continuously held snowfall forecasting contest for the NE CONUS on the Internet.

The Contest is open to any and all of the following:
Amateur and professional forecasters; broadcasters with or without trained Seals; weather-biz types and wanna-bees; wish-casters...astrologers...and other class of dreamers; Pollyannas or Cassandras; registered Nostradamusts; non-violent megalomaniacs; woolly-bear caterpillars or their agents; pest detectives...NE.Wx Usenet NG or GoogleGroup regulars and lurkers...refugees from EUSWx...StormVista...Golden Snowball...and meteorologists.

What is a contest-worthy event?

Wednesday, December 17, 2008

Snow Storm #1: The Forecasts



Twelve forecasters including three rookies for the inaugural event. Not much of a storm...but a good warm-up for Friday/s event.

Station forecasts here.



Forecaster consensus for a northern New England event.



No support from teleconnections. Just lucky to get a barely contest-worthy storm.



Verification began last night @ midnight. Snowfall has all but ended over the forecast area at post time. Preliminary storm-total snowfalls will be posted Thursday evening with the final results available on the web site Friday evening.

Tuesday, December 16, 2008

Coupled Jets



Good looking signature ahead of Friday/s snow storm.

Transverse...ageostrophic circulations in the entrance region of the polar jet advect cold air into the storm from the NW. Transverse...ageostrophic circulations in the exit region of the sub-tropical jet advect moist air into the storm from the SE. Enhanced omega occurs at the intersection of these circulations.

GooFuS also throws in some additional forcing with strong...low-level...warm air advection.

Could be a memorable event.

Monday, December 15, 2008

Call for Forecasts: Snow Storm #1 - Winter '08 / '09

The season has started!

Warm-advection snowfalls expected late Tuesday night and continuing into Wednesday across northern New England. Monday evening/s NAM forecast projections have reversed course from its earlier anemic trend and now suggest storm-total snowfalls will be contest-worthy.

Make the best forecast and you/ll win one month of FREE access to StormVista GOLD. Details here

Deadline: Tuesday...16 December 2008 @ 10:59 PM EST

Forecast element: storm-total snowfall
Verification period begins: 12:01 EST Wednesday...17 December 2008

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

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

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

New and returning forecasters will 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.

------------------------------------------------------

The Northeast Weather Snowfall Forecast Contest (NEWxSFC) is celebrating its 10th anniversary this winter. The Contest began during the '99/'00 season on USENET/s ne.weather news-group. It/s the longest...continuously held snowfall forecasting contest for the NE CONUS on the Internet.

The Contest is open to any and all of the following:
Amateur and professional forecasters; broadcasters with or without trained Seals; weather-biz types and wanna-bees; wish-casters...astrologers...and other class of dreamers; Pollyannas or Cassandras; registered Nostradamusts; non-violent megalomaniacs; woolly-bear caterpillars or their agents; pest detectives...NE.Wx Usenet NG or GoogleGroup regulars and lurkers...refugees from EUSWx...StormVista...Golden Snowball...and meteorologists.

What is a contesy-worthy event?

Synopti-scope® Detects Storm Signal

(updated below)

May not have too much longer to wait for this season/s inaugural snow storm.

Today/s 96-hour projection from the 12z GooFuS resolves a weak...warm advection event over northern portions of the forecast area mid-week.

The polar HIGH located north-northeast of the wave weakens slightly but holds its position as the LOW moves into the waters off Cape Cod and the Gulf of Maine.

Snowfall outlook...using 10:1 QFP...produces a 5 - 7" swath along and either side of a line from BGM - CON - BGR.

UPDATE:
Snow still seen as likely Tuesday night and Wednesday over northern New England; however...QPF has been trending lower today. Local NWS WFOs and HPC all leaning toward a nuisance-type event...all of which raises doubts about whether this storm will be contest-worthy.

GO / NO GO decision after this evening/s model runs.

Friday, December 12, 2008

First Nor'easter - Winter '08 / '09

First nor'easter to affect the forecast area this season was a dud.

Respectable storm-total snowfalls were scarce...
CAR - 4.1
BGR - 4
PWM - T
CON - 1
BTV - 9.2
ALB - 0.1
BGM - 3.6

NWP did a good job waving off this event by picking up on its predominate liquid / freezing character several earlier in the week.


Click image to animate.

Tuesday, December 9, 2008

Coastal Teaser #2 - DEC '08

(updated below - update II)

Healthy-looking nor'easter progged for end of the week...one that could affect about half the forecast area with this year/s inaugural contest storm. There/s a retreating HIGH as the storm gains latitude; however...cyclogenesis off the VA Capes would keep some of the cold air from escaping.

QPF @ 10:1 spits out 10"+ for ALB...CON...PWM...and BGR. Columns are currently depicted as cold enough for higher ratios...but let/s not get too far ahead of the story. Hard to tell where the cloud-tops are from GooFuS soundings b/c the moisture layers aloft are always depicted as being too deep.



Better get a snow storm in now while there/s cold air afoot b/c LR solutions have a decidedly 'mild' look to them well into Week 2.

If this scenario plays out...a call for forecasts would be made Wednesday evening with a late Thursday deadline.

UPDATE:
12/9/12z progs not all that encouraging for enough frozen precipitation at more than a handful of forecast stations nor are they in good agreement wrt timing. Yesterday/s GooFuS had the event Friday into Saturday...now it/s moved up a day.



HPC paints a 40% probability mainly over northern New England...with icing farther south across CT and MA.

GO / NO GO decision pending this evening/s model run(s).

UPDATE II:
12/10/00z NAM continues recent trend in its depiction of THU / FRI nor'easter as mainly a cold rain event over the forecast area with narrow band of IP / SN limited to northern edge of precipitation shield.

Potential appears marginal at this time for adequate conditions to warrant a call for forecasts.

Monday, December 1, 2008

Season-total Snowfall Forecast Contest - Winter '08 / '09

(updated below - Update II)

Deadline for entries has passed.

There were 30 entries this year...seven (7) of which came from Rookies. Welcome and good luck.

Good to see a strong turn out of Veteran forecasters...too. Last year/s contest winner 'duxpond' was a rookie back then and he/s back this year to defend his title.

Everyone/s forecast will be posted later today on the Contest/s web page.

Just for grins...this year/s forecasts were verified against last year/s snowfall totals with these results...ranked 1 to 10:
  • garymcm
  • TQ
  • bubbler86
  • Donald Rosenfeld
  • jackzig
  • weatherT®
  • duxpond©
  • Mitchel Volk
  • Raven
  • Don Rooney
® = rookie
© = defending champion

Update:


Click image to enlarge.

Update II:
Ranked by storm total precipitation.
Blue (red) cells indicate lowest (highest) tercile.



Period-of-record normal (PORN) snowfall: 916.9"
5 (26) forecasts below (above) PORN.
Consensus forecast: 18.9% above PORN
Minimum storm total precipitation (STP) forecast: 72% of PORN
Maximum STP forecast: 74% above PORN

All forecasts have been posted to the Contest/s web site.