CONTEST STATUS - Updated: MON ... 11-DEC-17 @ 6 PM EST

Winter '17 / '18 - Snowfall Forecast Contests
19th Annual 'Regular Season'

Snow Storm #1
Call for Forecasts - CANCELLED
Insufficient areal coverage for more than nuisance snowfall amounts

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17th Annual 'Season-total'
Deadline for entries has passed
Forecasters' summary here

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Winter '16 / '17 - Snowfall Forecast Contests
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18th Annual 'Regular Season'
FINAL results here
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16th Annual 'Season-total'
FINAL results here

Friday, November 29, 2013

Winter '13 / '14 - 13th Annual Season-total Snowfall Forecast Contest - Call for Forecasts!

UPDATE:
Deadline extended to 11:59 PM EST Saturday...07-DEC-2013.
Had been unable to e-mail 'Call for Forecasts' announcements until today.

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NE.Wx's 13th annual ‘Season-total' Snowfall Forecast Contest is the absolute best...biggest...and probably ONLY chance to be recognized for your long-range snowfall forecasting acumen.

All you have to do is forecast the season-total snowfall at 25 east coast stations from RDU to CAR.

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The Contest is open to amateur and professional forecasters; broadcasters with or without trained Seals; any and all weather-biz types and / or wanna-bees; wish-casters...astrologers...along with any other universally recognized classes of dreamers; Pollyannas or Cassandras...registered Nostradamusts...non-violent megalomaniacs...woolly-bear caterpillars or their agents...pest detectives...NE.Wx NG veterans; refugees from AmericanWx and/or USWeather...including self-imposed exiles from Eastern...and of course... meteorologists.

In honor of USENET's ne.weather's patron saint Mr. Joseph Bartlo's final request (RIP)...trolls...goats...hat3-lsiters...and psests need not apply.

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Deadline:  SAT...30-NOV-13 @ 11:59 PM EST
Forecast element:  sum-total season-total snowfall @ each station
Forecast period:  01-DEC-13 through 31-MAR-14

Verification:  NWS preliminary climate reports (CLM or F6)
Error statistic:  total absolute error [Σ abs(forecast - observed)]

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Visit the Contest's website to enter your forecast.
Follow the link from 'Enter Season-total Forecast.'
Update your forecast as often as you want.  Only your last entry will be verified.

The reigning NE.Wx ‘Season-Total’ Snowfall Forecasting Champ-een is Donald Rosenfeld.
Last year's 'Season-total' forecast summary...verification...and final results ==> here.

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As always...there are NO costs...fees...advertising...or annoying requests for personal information to enter the contest.

Sunday, November 24, 2013

Winter '13 / '14 - Northern Hemisphere Annular Oscillations as Leading Indicators

UPDATE (04-DEC-14)
Winter/s '13 / '14 AO:  0.183

Chi-square analysis of the monthly indexes for the Northern Hemisphere Annular Oscillations (Arctic Oscillation (AO) and North Atlantic Oscillation (NAO)) suggest there's predictive value in the sign of their November values.

The contingency tables below show the number of events over the period of record (1950 - 2013) where the sign of November's AO or NAO index matched the sign of the three-month winter (D-J-F) average.


'True -' ==> NOV and Winter negative
'False -' ==> NOV negative and Winter positive

'False +' ==> NOV positive and Winter negative
'True  +' ==> NOV positive and Winter positive

The p-value represents the '95% confidence' threshold whether the two data sets are statistically independent.  If p-value is < 0.050, then the null hypothesis (the two data sets are independent) is rejected.

Both AO and NAO have p-values < 0.05; therefore, there's a relationship between the sign of their November index and the sign of their winter's average index.

When the AO's (NAO's) November index is negative, there is a 76% (56%) chance the winter's average index will also be negative.

It's important to note the relatively high 'false alarm' probability.
When November's AO (NAO) is negative, there's a 52% (30%) chance for a false alarm.


Charts show how the sign of November's AO (NAO) maps to the winter's average AO (NAO).

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The AO's (NAO's) current 30-day moving average is 2.119 (0.455) with Iittle chance of flipping to negative by month's end.  This suggests a 48% (70%) chance the average AO (NAO) index this winter will also be positive. The AO's false alarm probability is 24% (44%).

Add a westerly QBO into the mix and there are strong indicators this winter's Northern Hemisphere Annular Oscillations will average positive.

Winter '13 / '14 - Arctic Oscillation: NOV/s Daily Index 3rd Highest on Record

The Arctic Index (AO) reached 4.317 on 16-NOV...the third highest November value for the period of record (1950 - current).  Record high of 4.544 was set in 1979 followed by 4.444 in 1995.

Does this event offer any insight into the character of the upcoming winter?
Probably not.

QBO is correlated with the strength of the Polar Vortex (PV)
QBO-W (+) ==> strong PV ==> +AO
QBO-E (-) ==> weak PV ==> -AO

QBO-2013 is currently west (+)...has probably peaked...and will likely flip toward the end of the '13 / '14 winter.
QBO was wicked east the winter of 1979-80 and had just flipped into its easterly phase NOV-95.

MEI ESNO-79 was warm and cold in 1995.  La Nada is forecast for ENSO-13.


Chart:  30-day moving averages for AO...NAO...and PNA (SEP-11 through NOV-13).
Daily index data here.

Winter '13 / '14 - Outlooks

Thread updated periodically as new outlooks and forecasts are issued from a variety of sources.

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WxAmerica...

Since this upcoming winter season looks to be close to climatology (normal/mean appearance), the harshest period of December 23 - February 14 will likely be characterized by strong and persistent high-latitude blocking.
Whereas November and the first three weeks of December will likely have a more "up and down" or erratic character, suppressed storm tracks and strong Arctic intrusions are likely in the dead of winter.
The "January Thaw" may be short, with the potential for a fairly vast -EPO/-AO/-NAO alignment keeping colder air in play.

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Climate Prediction Center 0.5 month long-lead (Last Call!)...