CONTEST STATUS - Updated: SAT ... 14-APR-18 @ 9 PM EDT

Winter '17 / '18 - Snowfall Forecast Contests

19th Annual 'Regular Season' Snowfall Forecast Contest
- FINAL Results here
1st Place: Brad Yehl
2nd Place: Don Sutherland
3rd Place: NWS ER WFOs
HM: Herb @MAWS

17th Annual 'Season-total' Snowfall Forecast Contest
- FINAL Results here
1st Place: Don Sutherland
2nd Place: Mitchel Volk
3rd Place: Brad Yehl
Climo: 5th place

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

16th Annual 'Season-total'
FINAL results here

Tuesday, December 20, 2011

Winter '11 / '12 - Arctic Oscillation - Day 20

The persistantly positive state of the Arctic Oscillation (AO) may be starting to lean toward a long awaited change of sign.

This three day Height-Latitude Cross Section of Zonally Averaged Zonal Wind loop shows deep-layer easterly winds blowing over the pole...a weakening polar vortex (PV)...and a strengthening sub-tropical jet (STJ)...all of which are favorable ingredients for the Arctic Oscillation to finally go negative.

As a result...the AO has ducked below zero for the first time in what seems like ages.


Whether this trend continues remains to be seen.
Recent daily AO data here.

Contours show zonal wind speed with an interval of 2.5 m/s.
Easterly winds are shaded in warm colors.
Graphics courtesy the Japanese Meteorological Agency (JMA).

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