Winter '15 / '16 - Snow Storm #2: RAW Forecasts

Here

Winter '15 / '16 - Snow Storm #2: Call for Forecasts

MDT
07-FEB-67

Riding the 18z NAM and GFS.
Minimum number of stations in play.
A few more are close enough.

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Forecast element: storm-total snowfall
Deadline: 10:30 PM EST ... MON ... 08-FEB-16
Verification period begins: 12:01 AM EST ... TUE ... 09-FEB-16
Verification period ends: when the snow stops falling

Enter your forecast at the NEWxSFC/s home page @ http://www.newx-forecasts.com/
Follow the top-of-page link from 'Enter Storm Forecast.'

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As always ... there/s no cost ... no fee ... no advertising ... or annoying requests for personal information to enter a forecast.  It's just a fun exercise for winter wx enthusiasts to see who can make the best synoptic-scale snowfall forecast.

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If you are issuing your first forecast this winter ... or you entered the 'season-total' forecast contest ... you/ll need to create an account (user name / password / valid e-mail ... if you want a copy of your forecast sent to your Inbox.

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Contest may be cancelled before deadline if storm appears to fizzle.

Winter '15 / '16 - Phantom Storm #1

Today/s poorly-forecast nor'easter turned out to be a decent contest-worthy snow storm over coastal portions of southern New England.

Insufficient lead time to issue a 'Call for Forecasts.'

Near-blizzard conditions on Cape Cod.
Who knew?

Storm-total snowfall (")
ORH - 12.5
ISP - 9.8
PVD - 8.8
BDR - 8
BGR - 7.8
BDL - 6.6
CON - 5.1
PVD - 5.1
BOS - 4.6
JFK - 4.6
EWR - 2.8

Winter '15 / '16 - Sudden Stratospheric Warming: Watch #2

UPDATE (01-FEB-18):
As advertised ...

 

 

Looks yuge.

Beat the rush.
Start laying in supplies now.

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10 mb Temperature Anomalies
GFS Ensembles 10-JAN-16

"The models are now coming into better consensus for a stronger pulse of energy transfer beginning next week that is predicted to initiate a sudden stratospheric warming (SSW) at the end of the month."

 -  AER Arctic Oscillation Analysis and Forecasts (time sensitive)

Progs expect PV displacement v. PV split.

Winter '15 / 16 - Snow Storm #1: NESIS

Rank:  4
NESIS:  7.66
Category:  4
Description:  Crippling

Large format image here.

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The storm covered ~434,000 square miles and affected ~103 million people.

Of those, ~1.5 million people had more than 30" of snowfall; ~24 million had over 20".
- NOAA

Winter '15 / '16 - Snow Storm #1: FINAL Results

Full forecast verification and summary at NEWxSFC/s web site.

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	1st - Donald Rosenfeld
	SUMSQ:	1152.22
	SUMSQ Z:	-1.946
	STP:	14.0	(1)
	TAE:	135.8	(1)
	AAE:	5.22	(1)
	2nd - TQ
	SUMSQ:	1802.59
	SUMSQ Z:	-0.968
	STP:	108.6	(6)
	TAE:	143.9	(3)
	AAE:	6.00	(3)
	3rd - Mitchel Volk
	SUMSQ:	1942.0
	SUMSQ Z:	-0.759
	STP:	127.3	(7)
	TAE:	156.5	(5)
	AAE:	6.80	(6)
	HM - donsutherland1
	SUMSQ:	2151.8
	SUMSQ Z:	-0.443
	STP:	142.2	(9)
	TAE:	160.7	(6)
	AAE:	6.70	(5)

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SUMSQ: sum of square errors
STP: storm-total precipitation error
TAE: total absolute error
AAE: average absolute error
(number): category rank

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Click images to enlarge.

Winter '15 / '16 - Snow Storm #1: Preliminary Verification

Preliminary storm-total snowfalls for Friday though Sunday from CDUS41 and CXUS51 bulletins.  Good coverage and reporting.

DCA STP in question.
Vicinity reports suggest an under-measurement.
Sensitivity analysis on forecasts with a 30" verification shows no impact on top three finishers (HM flips) with minor shuffling in the pack's middle.
Note the SLRs are similar at IAD and BWI.

AP reporting on the controversy.
The two vicinity sites mentioned in the article are ~3 miles NNW (Adams Morgan neighborhood) and ~5 miles NW (Dalecarlia Reservoir) distant from DCA.

Meanwhile ... ~2 miles across the river to the east in Anacostia ... MD ... a trained spotter reported 19" and about the same distance to the SSE a 17" report from National Harbor ... VA

Reporting issues continue at SBY.
SBY/s 6" STP comes from a 'media' report carried in AKQ/s Public Information Statement (PNS).

HYA/s 14" STP comes from an 'amateur radio' report carried in BOX/s Public Information Statement (PNS).

Stations with STP but no SN:H2O had mixed freezing ... frozen ... and liquid precipitation.

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Boatload of new daily records for SAT ... 23-JAN-16
JFK - 30.3" (3.6"; 2005)
ABE - 30.2" (7.7"; 1966)
EWR - 27.5" (4.5"; 2005)
MDT - 26.4" (9.5"; 1982)
BWI - 25.5" (11.5"; 1935)
ISP - 23.4" (4.2"; 2005)
IAD - 22.1" (1.7"; 1982)
PHL - 19.4" (11.9"; 1935)
BDR - 12" (7.1"; 1965)
DCA - 11.3" (11"; 1935)
ACY - 10.1" (1.2"; 1948)
RIC - 5.3" (2.7"; 1908)
ORF - 1.2" (1"; 2000)
RDU - 1.2" (1.2", 1954) [22-JAN-16]

Areal coverage - The Great non-blizzard Blizzard JAN 2016

 

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Several new daily records exceeded those set in 1935.

Remarkably similar synoptics.
Parent HIGH over the upper Plains with an eastern extension over the NE.
Miller 'B' re-development off the Carolinas.

 

STP (liquid)

DC - 2.85"

BWI - 2.68"

RIC - 2.88"

 

 

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Please report any errors in Comments along with a link to the correct data.
Final results Tuesday evening.

Winter '15 / '16 - Snow Storm #1: DCA STP #FAA_FAIL

24-JAN-16
The 2016 non-blizzard Blizzard

UPDATE 1/25:
AP reporting on the controversy.

The two vicinity sites mentioned in the article are ~3 miles NNW (Adams Morgan neighborhood) and ~5 miles NW (Dalecarlia Reservoir) distant from DCA. 

Meanwhile ... ~2 miles across the river to the east in Anacostia ... MD ... a trained spotter reported 19" and about the same distance to the SSE a 17" report from National Harbor ... VA.

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Apparently ... DCA reported 17.8" STP (1.47 liquid) yet IAD and BWI measured 29.3" (2.63 liquid) and 29.2" (2.13 liquid) ... respectively.

This disparity has lead to questions about how much snow actually fell @DCA.

NWS vicinity reports in the PNS bulletin also suggest a possible under-measured of snow at Raygun/National.

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Reported snow liquid ratios (SLR)
DCA 12.1
IAD 11.1
BWI 13.7

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FAA contract personnel measure snowfall at many major airports.  May be one reason why so many SLRs are 10:1. 

That ... and not being able to find the snowboard when it's time to measure.

Winter '15 / '16 - Snow Storm #1: The Forecasts!

Rookie 0
Intern 0
Journey 0
Senior 13
TOT 13

Congratulations to snocat918 on achieving Senior forecaster status this season.

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Forecasts are ranked by their storm-total precipitation (STP).

BLUE ==> 25th percentile.
RED ==> 75th percentile.
Grey and white STP cells are between the 25th and 75th percentile.

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Heaviest snowfall (+12") consensus along and the the right of RIC - IAD - MDT - PHL - BWI - RIC.
Lollypop expected at IAD.

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Northern annular modes (AO / NAO) negative and rising.  Evidence of amplifying long wave seen in PNA/s rising index.

Everyone/s station-by-station forecast at the Contest/s web site.
RAW forecasts here.

Winter '15 / '16 - Snow Storm #1: RAW Forecasts

Baltimore ... MD
28-JAN-22

RAW forecasts here.

All forecasts and summary statistics will be posted at the Contest web site and the web log ... respectively after lunch FRI.

Having issues with Excel this AM.