Wednesday, April 08, 2015

Winter '14 / '15 - Season-total Snowfall Forecast Contest: MAR Totals

Monthly station snowfall summary for MAR-15.
Rank ordered by percent of monthly normal.


Green ==> 75th percentile
White ==> Less than 75th and greater than 25th percentile
Red ==> 25th percentile
 
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Teleconnection Indexes
AO:  +1.837
NAO:  +1.45
PNA:  +0.49
PDO:  2.00
QBO:  -28.15 (monthly record)
MEI:  .650 (FEB-MAR)

Saturday, March 28, 2015

Winter '14 / '15 - Sudden Stratospheric Warming: Watch #2 - Update 4

Incoming!

 
Deep layer Easter easterlies.
 
 
PV displacement
 
Split vortices.
 
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Major SSW event has begun!
 
 

Wednesday, March 25, 2015

Winter '14 / '15 - Sudden Stratospheric Warming: Watch #2 - Update 3

ECMWF continues its forecast for a SSW event in the near-term.

Monday, March 23, 2015

Winter '14 / '15 - Sudden Stratospheric Warming: Watch #2 - Update 2

Complete break down of the Polar vortex at month's end.
Deep ... deep layer wind reversal (easterlies up and down the Polar atmosphere) 
 

Prediction:  cold spring in the east.

Tuesday, March 17, 2015

Winter '14 / '15 - Sudden Stratospheric Warming: Watch #2

ECMWF predicts a reversal by displacement of the Polar vortex beginning 24-MAR-15 ...


... and a deep ... icy trough INVOF Baffin Bay.
 
mid-to-late April could turn out quite interesting.

Wednesday, March 11, 2015

Winter '14 / '15 - Season-total Snowfall Forecast Contest: FEB Totals

Monthly station snowfall summary for FEB-15.
Rank ordered by percent of monthly normal.


Green ==> 75th percentile
White ==> Less than 75th and greater than 25th percentile
Red ==> 25th percentile
 
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Teleconnection Indexes
AO:  +1.043
NAO:  +1.32
PNA:  +0.49
PDO:  +2.30 (monthly record)
QBO:  -28.62 (monthly record)
MEI:  +0.468 (JAN-FEB)

Monday, March 09, 2015

Winter '14 / '15 - Interim Standings: 5

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


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Complete interim statistics table and charts at the Contest/s web site here.
All verified forecast statistics from all forecasters for all Winter '14 / '15 contest storms here.

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SUMSQ errors for each contest snow storm are normalized with a 'Z-score' ... then averaged to compute the standings.

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