CONTEST STATUS - Updated: THU ... 31-OCT-19 @ 12:16 PM EDT

Winter '19 / '20 - Snowfall Forecast Contests
21st Annual 'Regular Season' Snowfall Forecast Contest
Contest starts once the flakes start a'flyin'

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19th Annual 'Season-total' Snowfall Forecast Contest
Deadline for entries: 11:59 PM EST ... SAT ... 30-NOV-19
Verification period: 01-DEC-19 through 31-MAR-20
Details here

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Winter '18 / '19 - Snowfall Forecast Contests
20th Annual 'Regular Season' Snowfall Forecast Contest
FINAL Results here

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18th Annual 'Season-total' Snowfall Forecast Contest
FINAL Results HERE
Forecaster verification table HERE

Wednesday, August 21, 2019

Winter '18 / '19 - Arctic Oscillation (AO) Analog Verification

The analog forecasting technique seeks associations to the AO state in the run-up to the coming winter with AO run-up states of past winters.  Presented here is the verification of AO analogs for the '18 /'19 winter.

The NEWxSFC method ranks analog years by their the sum of square errors (SSE) statistic.
Lower SSE errors ==> stronger analog

Constraining the number of analog winters for analysis to five is arbitrary.

In the run-up to Winter '18 / '19 ... '55 / '56 was the leading analog followed by '64 / '65 ... '84 / '85 ... '99 / '00 ... and '91 / '92.  Observed AO values for Winter '18 / '19 began neutral in DEC ... turned weakly negative in JAN ... then surged positive at meteorological winter/s end and into MAR.

A qualitative assessment of the analog forecast/s accuracy rates '84 / '85 as best.

A quantitative assessment of the other '84 / '85 teleconnections ... not so much.