Saturday, December 17, 2016

Winter '16 / '17 - Snow Storm #1: Near Miss

ACY Boardwalk (1928)
The season/s first snow storm out-performed not only the numerical models but the professional meteorologists responsible for issuing the official forecasts.

Heaviest significant snowfall (>= 4") at first-order reporting stations was observed along and either side of a line from CON - BOS - BDR - BDL - ORH - CON.  In addition to these five forecast points ... PWM at 3.6" and CAR at 3.5" ended up being close enough to have warranted a 'call for forecasts' and a contest-worthy snow storm had the writing been on the wall Thursday evening.  As it was ... NE snowstorm legend Paul Kocin painted a large swath of 40% probability for at least 4" on WPC/s afternoon package.

Models were late catching on to this storm/s potential.  Similar circumstances plagued last year/s contests ... as well.

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Station / snowfall (")
BDL 6.5 (daily record)
ORH 6
BDR 5.3 (daily record)
CON 4.7
BOS 4.3
PWM 3.6
CAR 3.5
BGM 3.4
BGR 3.3
PVD 3.2
BTV ... ISP 3
EWR ... JFK 3 (daily records)
HYA 2.5 (est.)
ALB 2.4
ABE ... MDT ... PHL <1
ACY ... BWI ... IAD ... DCA T



2 comments:

Unknown said...

Maybe need to rethink when to have a "call for forecasts". If it has a chance of being a storm we send in predictions and it is only a contest worthy storm if X number of stations see 4" plus of snow. That way we don't "miss" a storm and if it never develops we toss the forecasts and wait for the next one.

TQ said...

If it were only than simple :)
Hybrid storms (snow-to-rain) are the most difficult.

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A lot of work comes with issuing a 'Call for Forecasts'.

Hundreds of emails have to been sent (50 at a time ... 30' apart so as not to be flagged as spam or blocked by my ISP).
The contest/s web site has to be updated.
The contest/s web log has to be updated.

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Then it becomes a judgment call deciding whether the storm was contest-worthy (six to eight stations with more than nuisance storm-total snowfall i.e., >= 4").

Collecting surface ... upper air ... and remote sensing data used in the final analysis and storm summary reporting takes time while the event is unfolding. All for naught if the storm fizzles.

Believe you me ... no one is more disappointed when a snow storm slips through the cracks.
Bottom line: a contest-worthy storm has to be reasonably well predicted by the numerical models and WPC 24-to-36 hours before the first flakes fall for a 'Call for Forecasts' to be issued.