Winter '21 / '22 - Snow Storm #3: Preliminary STP verification

Boston Commons
Parkman Bandstand - 1933

CORRECTION:  daily snowfall record for BDR (had been listed as BGM) and BOS daily snowfall for 1/28/22 from 0.02" to 0.2".

h/t Roger Smith

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Preliminary verification of storm-total snowfalls for FRI through SUN from CDUS41 (CLI) ... CXUS51 (CF6) ... METARs ... and PNS bulletins.  Several issues with coverage and reporting.

HYA
STP estimated from PNSBOX reports using inverse distance weighting of vicinity reports.
http://en.wikipedia.org/wiki/Inverse_distance_weighting

CAR
Resolved conflict between 29-JAN-22 daily snowfall reports carried by Daily Climatological Report (CLI) of 9.2" and Daily Climate Data (CF6) of 8.2" by comparing vicinity PNSCAR storm-total snowfall reports.  The 1" difference made no difference in final rankings of the forecasts; however ... minor differences noted in the SUMSQ Z-score statistic.

BGR
Liquid equivalent missing from Daily Climatological Report (CLI) and Daily Climate Data (CF6) reports for 29-JAN-22.  Amount estimated from METAR reports from AWOS at Hancock County-Bar Harbor Airport (KBHB) in East Surry ... ME.

Liquid equivalents recovered from METARS for several stations with missing data in climate bulletins.

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Snow-to-liquid ratio (SLR) not reported for some stations with measurable snowfall b/c significant liquid and / or freezing precipitation also occurred during the verification period.

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Stations observing >= Trace:  27 (100%)

Given stations had measurable snowfall ... stations observing at least:
4" - 17 (63%)
8" - 12 (44%)
12" - 7 (26%)
16" - 5 (19%)
20" - 2 (7%)
24: - 1 (4%)

Max snow melt-water (minimum SLR 10:1)
ACY - 1.60"
CAR - 0.92"
BGR - 0.82"

Max precipitation (frozen + freezing + liquid):
ACY - 1.60"
CAR - 0.92"
BGR - 0.82"

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New daily record(s)
29-JAN-22
BOS - 23.6" (3.7"; 1957)
ISP - 23.2" (1.5"; 2014)
PVD - 18.8" (6.7"; 1912)
ORF - 14.7" (11.5"; 1973)
ACY - 14" (7.3"; 2014)
PWM - 11" (9"; 1957)
BDR - 9.6" (3.8"; 1973)
JFK - 9.3" (1"; 2014)
EWR - 6.6" (1.1"; 1986)
PHL - 5.8" (5"; 1904)

Orange cells indicate new daily record.
Trace amounts (0.05") are not included in STP.

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Storm total snowfall
Image courtesy NOHRSC

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SFC analysis:  18z ... 29-JAN-22
Image courtesy DOC / NOAA / NWS / NCEP / WPC

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Please report any errors in Comments along with a link to the correct data.
FINAL results expected NLT TUE evening.

Winter '21 / '22 - Snow Storm #3: The Forecasts

BGR
01-JAN-63

Rookie      1
Intern      1
Journey      -
Senior      12
GOVT      1
PWSP      1
TOT      16

Forecaster table ranked ascending by storm-total precipitation (STP)

BLUE ==> 1st quartile
RED ==> 4th quartile
WHITE and GREY STP cells range between the 1st and 4th quartile

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Heaviest snowfall (+12") consensus along and more-or-less to the right of BGR - PWM - BOS - HYA - PVD  - ISP - ACY - ISP - ORH - BGR.  Lollypop expected at HYA.

Teleconnections
Pretty impressive storm for such lousy indexes.

Everyone/s station-by-station forecast at the Contest/s web site.
Direct link to the forecast table.

Winter '21 / '22 - Snow Storm #3: RAW Forecasts

click Read more ...

NWS to follow.

Read more »

Winter '21 / '22 - Snow Storm #3: Call for Forecasts!

Knickerbocker Theatre
27/29- JAN-1922

High amplitude flow regime across CONUS ... courtesy RIDGE - WEST / TROF- EAST longwave configuration ... appears primed to deliver one heck of a contest-worthy snow storm for the last weekend of JAN.  It/s also the 100 year anniversary of the Knickerbocker Theatre fire.

- Enter your forecast at the NEWxSFC/s home page at http://www.newx-forecasts.com/

- Follow the top-of-page link from 'Enter Snow Storm Forecast'

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Forecast element: each station/s storm-total snowfall

Deadline for entries: 10:00 PM EST ... THU ... 27-JAN-22

Verification begins: 12:01 AM EST ... FRI ... 28-JAN-22
Verification ends: 11:59 PM EST on the day when flakes stop accumulating.

You also get the chance to see how well your forecast stacks up against NWS Eastern Region Weather Forecast Offices. Turns out they/ve been fairly easy to beat!

Who Can Enter
Amateur and professional forecasters; broadcasters with or without trained Seals; any and all other weather-biz types and / or wanna-bees; wish-casters ... astrologers ... along with any other universally recognized class of dreamers; Pollyannas or Cassandras ... registered Nostradamuses ... non-violent megalomaniacs ... woolly-bear caterpillars or their Agents ... pest detectives ... ne.wx NG survivors; riders on the StormVista ... refugees from AmericanWx and/or USWeather free agents ... including self-imposed exiles from Eastern Wx ... and of course ... meteorologists.

Read more »

Winter '21 / '22 - Coastal Teaser #3

DC
24-JAN-1940

Persistent Ridge-West / Trof East mid-level flow regime looking to cough up another contest-worthy snow storm this coming weekend.

Progs pointing to a Miller 'A' type storm beginning its long climb up the east coast on FRI then exploding into a meteorological 'bomb' (and no ... not a so-called 'bomb cyclone'; a made-up term never used by Sanders and Gyakum 1980) during SAT.

A 'Call for Forecasts' expected WED ... 26-JAN-22.

All else equal ... deadline for entries would be 10 PM EST ... THU ... 27-JAN-22.

Winter '21 / '22 - 'Season-total' Snowfall Forecast Contest: DEC Snowfall Totals

DEC-21 snowfall summary by forecast station.
Rank ordered descending by percent of monthly period-of-record-normal (P-O-R-N).

Green ==> 4th quartile
White ==> less than 4h and greater than 1st quartile (inter-quartile range)
Red ==> 1st quartile

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DEC Forecast Station Highlights
0 stations above normal monthly snowfall

Biggest Losers
ABE ... ACY ... BDR ... BOS ... BWI ... DCA ... EWR ... IAD ... NYC ... ORF ... PHL ... RDU ... RIC ... SBY observed less than 10% of normal monthly snowfall

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Season-Total-to-Date
DEC P-O-R-N contributes 203.3" (22%) toward the season-total snowfall (D-J-F-M) of 929".
DEC-21 observed snowfall:  86" (42% of monthly P-O-R-N; 9% of season-total snowfall)

Image courtesy NOHRSC @ http://www.nohrsc.noaa.gov/nsa/

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Teleconnections
AO / NAO / PNA data

Winter '21 / '22 - Snow Storm #2: FINAL Results and Storm Summary

Complete forecaster verification table and the FINAL Results / Storm Summary available at NEWxSFC/s home page.

SUMSQ:  sum of square error (")
SUMSQ Z:  Z-score
STP:  storm total precipitation error (")
TAE:  total absolute error (")
AAE:  average absolute error (")
(#):  category rank

Forecast by Observed Snowfall Scatterplots for Top Forecasts
Forecast/s dotted blue line below (above) the Observed snowfall/s solid red line ==> under (over) forecast bias.

Station by Station Comparison of Top 4 Forecasts and Observed Storm-total Snowfall

Forecast bias (average over/under per station) and skill score v. NWS ER WFOs.
For example ... Shillelagh's bias was on average a 1" under-forecast  The forecast was a 47% improvement over NWS ER WFOs.

Winter '21 / '22 - Snow Storm #2: Preliminary STP Verification

Preliminary verification of storm-total snowfalls for SUN through TUE from CDUS41 (CLI) ... CXUS51 (CF6) ... METARs ... and PNS bulletins.  Excellent coverage and reporting.

HYA
6- and 7-group precipitation data not carried in METARS.

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Snow-to-liquid ratio (SLR) not reported for some stations with measurable snowfall b/c significant liquid and / or freezing precipitation also occurred during the verification period.

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Stations observing >= Trace:  24 (89%)
Given stations with measurable snowfall ... stations observing at least:
4" - 5 (19%)
6" - 3 (11%)
8" - 2 (7%)
10" - 1 (4%)

Max snow melt-water (minimum SLR 10:1)
BGM:  1.18"
BTV:  0.57"

Max precipitation (frozen + freezing + liquid):
ORF:  1.97"
EWR:  1.87"
ISP:  1.60"

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New daily record(s)
16-JAN-22
DCA - 2.6" (2.2"; 1965)

17-JAN-22
BTV - 8.1" (8"; 1909)

Orange cells indicate new daily record.
Trace amounts (0.05") are not included in STP.

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Storm total snowfall
Image courtesy NOHRSC

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SFC analysis:  12z ... MON ... 17-JAN-22
Image courtesy DOC / NOAA / NWS / NCEP / WPC

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Please report any errors in Comments along with a link to the correct data.
FINAL results expected NLT THU evening.

Winter '21 / '22 - Snow Storm #2: Preliminary STP Verification

STATUS:  Preliminary STP table will be posted tomorrow ... WED ... 19-JAN-22 to account for snowfall observed today ... TUE ... 18-JAN-22.

The cyclonic circulation around the occluded MLK surface LOW near the mouth of the St. Lawrence River produced measurable 'lake effect' snowfall at BGM earlier today.

Winter '21 / '22 - Snow Storm #2: The Forecasts!

BWI
13-DEC-60

Rookie      2
Intern      1
Journey      -
Senior      12
GOVT      1
PWSP      1
TOT      17

Forecaster table ranked by ascending storm-total precipitation (STP)

BLUE ==> 1st quartile
RED ==> 4th quartile
WHITE and GREY STP cells range between the 1st and 4th quartiles.

Heaviest snowfall (+5") consensus along and to the right of CAR - CON - ALB - BGM - BTV - CAR  Lollypop expected at BTV.

PNA making a half-hearted effort but NAO and AO just not that interested.

Everyone/s station-by-station forecast at the Contest/s web site.
Direct link to the forecast table.