CONTEST STATUS - Updated: MON ... 19-MAR-18 @ 7:20 PM EDT

Winter '17 / '18 - Snowfall Forecast Contests

19th Annual 'Regular Season'
- Interim Standings ... as of Snow Storm #6 here
- Forecaster Storm Stats ... as of Snow Storm #7 here

- Snow Storm #8
Call for Forecasts!
Deadline: 10:30 PM EDT ... TUE ... 20-MAR-18
Details 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

Wednesday, December 29, 2010

Winter '10 / '11 - Snow Storm #1 - Storm Evolution at 500 MB

Short-wave trough comes ashore in southern CA on 23-DEC-10...undercuts the short-wave ridge axis over the Rockies on the 24th...then phases with a northern stream short-wave in over the lower MS River Valley.  Note the strong cold air advection (CAA) driving the northern stream short-wave at 00z on the 26th prior to the phasing which causes the wavelength to shorten and amplify.

The mid-level circulation begins to close off 12 hours later at 12z on the 26th followed by a 12-hour 180 m height-fall between 00z and 12z on the 27th.  Large height-falls at 500 MB indicate strong cooling aloft associated with strong upward vertical motion (UVM).

Stream-phasing was one element behind the flip-flopping of NWP solutions in the run-up to the snow storm.

Graphics courtesy University of Wyoming

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