CONTEST STATUS - Updated: FRI ... 23-MAR-18 @ 6 PM EDT

Winter '17 / '18 - Snowfall Forecast Contests

19th Annual 'Regular Season'
- Interim Standings ... as of Snow Storm #7 here
- Forecaster Storm Stats ... as of Snow Storm #7 here

- Snow Storm #8: 21-MAR-18
The Forecasts! here
Preliminary STP verifications here

- Snow Storm #7: 12-MAR-18
FINAL Results here
Winning forecast issued by: iralibov

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

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

16th Annual 'Season-total'
FINAL results here

Sunday, December 28, 2014

Winter '14 / '15 - Weakening Polar Vortex ==> Sudden Stratospheric Warming: UPDATE 3

Minor warming in progress INVOF Siberia.

10-hPa temperature change in a week in the Northern Hemisphere
The contour interval is 5 °C. The pink and light blue shadings indicate warming and cooling, respectively. The red shading denotes warming for values higher than 25 °C.
"A stratospheric warming is called 'minor' if a significant temperature increase is observed ([...] >= 25°C in a ... week or less) at any stratospheric level in any area of winter time hemisphere. The polar vortex is not broken down and the wind reversal from westerly to easterly is less extensive." (REF)
Imagery courtesy Tokyo Climate Center, Climate Prediction Division

Major warming appears imminent.

"Major SSWs occur when the westerly winds at 60N and 10 mb  reverse direction. A complete disruption of the polar vortex (PV) is observed.  The PV will either be split into daughter vortices ... or be displaced from its normal location over the pole." (WMO)

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