CONTEST STATUS - Updated: WED ... 13-DEC-17 @ 8:30 PM EST

Winter '17 / '18 - Snowfall Forecast Contests
19th Annual 'Regular Season'
Snow Storm #1
Synoptiscope in VCP32

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

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

Thursday, November 24, 2011

Winter '11 / '12 - Great Appalachian Storm of 1950


Kevin Myatt at the Roanoke Times reminds us of a blockbuster snow storm from a Thanksgiving weekend long ago. 

Known at the time as 'The Storm of the Century' ... Miller 'B' cyclogenesis occurred along shore of the Carolinas on the 24th ... rapidly deepened (26mb / 12hrs) over the Chesapeake Bay  / Delmarva on the 25th...then became trapped beneath a strong 1042 mb blocking HIGH to its north.

Kevin notes...

"The Great Appalachian Storm of 1950 left behind 9 inches of snow in Roanoke and 14inches in Wytheville, with 4 to 12 inches common across our region (ED:  SW VA).

"But it was far worse elsewhere. Parts of West Virginia, eastern Kentucky and western Pennsylvania saw 2 to 4 feet of snow. Winds topped 100mph in New York. The storm is blamed for more than 300 deaths and about 1million people cut off from electricity."
Some other interesting minutia about this historic early season snow storm...

Snowfall totals...
Youngstown...OH - 29"
Pittsburg...PA - 30"
Elkins...WV - 34"

Notable wind gusts were observed at...
Newark (EWR)...NJ - 108 mph
Bear Mountain (N of NYC) - 140 mph
Concord (CON)...NH - 110 mph
Mount Washington (MWN)...NH - 160 mph

Other storm effects...
- Coastal flooding breached dikes and flooded runways at LaGuardia Airport in New York.
- Crop damage and record minimum temperatures in the deep south (Birmingham:  5°F; Atlanta:  3°F;  Nashville:  -1°F)
- Some coastal areas in New England reported greater damage than the famed '38 hurricane.
- "...(T)he Ohio State-Michigan football game went on as scheduled (in Columbus), despite blizzard conditions. Nearly 50,000 fans showed up to watch the “Blizzard Bowl,” with a Rose Bowl berth the payoff. Michigan won the game 9–3 without making a single first down and only gaining 27 yards on offense." (Weatherwise Mar-Apr 2011)

Charts and graphs after the jump.
The event was poorly forecast by the manual methods common to the era and later served as the impetus for the development of numerical weather prediction (NWP) models.


Northern annular indexes were both strongly negative with the Arctic Oscillation rising sharply in the days before coastal cyclogenesis.


Other teleconnection indexes for NOV...
PDO:  -2.46
QBO:  -2.18 (extended period of negative state)
MEI:  ON -1.168 ND -1.261 (moderate la Nina)
Sun spots:  54.8 (quite sun - relative min during last quarter of Cycle 18)

The storm didn't make the cut for a NESIS rating even though it was a long duration event and laid down deep snows across several states.

From the Daily Wx Map archives...
SAT 25-NOV-50 and SUN 26-NOV-50

From Monthly Weather Review (NOV-50)...
Full latitude trof along 85W.  Note the strong warm air advection into the western edge of the western Atlantic ridge impeding the trof from lifting out.
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Other resources...
NWS Jackson NY - The Great Appalachian Storm of 1950
Monthly Weather Review - The Destructive Storm of November 25-27, 1950 (.pdf)
Wikipedia - Great Appalachian Storm of November 1950
The Norm Phillips Symposium - Thanksgiving Weekend Storm of 1950

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