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

'53 Chevy
Deep Pt. Pleasant ... NJ (JAN-64)

JAN-22 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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JAN Forecast Station Highlights
20 stations at or above normal monthly snowfall.

Biggest Loser - ALB with 51% of its monthly normal snowfall.

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Season-Total-to-Date

JAN P-O-R-N contributes 279" (30%) toward the season-total snowfall (D-J-F-M) of 929".
JAN-22 observed snowfall:  439" (142% of monthly P-O-R-N; 46% of season-total snowfall)

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

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Teleconnections
AO / NAO / PNA data

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DEC snowfall totals:
https://newxsfc.blogspot.com/2022/01/winter-21-22-season-total-snowfall.html

Winter '21 / '22 - Snow Storm #4: 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 4 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

Forecast Skill Score measured against NWS ER WFOs
A positive skill value indicates the forecast/s improvement over the NWS forecasts.
Bias is the arithmetic difference between the average Forecast snowfall and the average Observed snowfall.

Winter '21 / '22 - Regular Season: Interim Standings #1

After a Blizzard
Marion Post Wolcott
Woodstock ...VT (1940)

Under the ‘two-thirds’ rule … forecasters who have entered at least TWO forecasts are included in Interim Standings #1.

Complete interim statistics table and chart at the Contest/s web site here (direct link)
Forecaster statistics for Winter '21 / '22 contest snow storms here (direct link)

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SUMSQ errors for each contest snow storm are normalized (i.e., standardized) with a 'Z-score' ... then averaged to compute the standings. If a forecaster has issued forecasts for more than two-thirds of all snow storm contests ... then Z-scores from their 'best two-thirds' forecasts are used to calculate the Interim and Final standings.

Similar idea as dropping the lowest test score before computing the final grade.

Winter '21 / '22 - Snow Storm #4: Preliminary STP Verification

Franklin ... NJ (FEB-1923)

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

HYA
STP estimated from NOHRSC reports using inverse distance weighting of vicinity reports.

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

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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:  23 (85%)
Given stations had measurable snowfall ... stations observing at least:
4" - 4 (15%)
8" - 3 (11%)
12" - 3 (11%)

Max snow melt-water (minimum SLR 10:1)
BTV - 1.02"
BGR - 0.79"
CAR - 0.76"

Max precipitation (frozen + freezing + liquid):
ABE - 2.230"
ORH - 2.22"
CON - 2.20"

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New daily record(s)
03-FEB-22
BTV - 6.5" (6.2"; 1910)

04-FEB-22
BGR - 11.4" (9.6"; 1990)

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Daily STP table.  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:  06z ... 04-FEB-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 MON evening.



 

Winter '21 / '22 - Forecaster Storm Statistics

Port Washington ... NY
02-FEB-61

Forecaster's summary statistics for snow storms #1 through #3 here.

Winter '21 / '22 - Snow Storm #4: The Forecasts

NYC
02-FEB-69

Rookie      -
Intern      1
Journey      -
Senior      6
GOVT      1
PWSP      -
TOT      8

 

 

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

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

Teleconnections

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

Winter '21 / '22 - Snow Storm #4: RAW Forecasts

 click through on Read more ...

Read more »

Winter '21 / '22 - Snow Storm #4: Call for Forecasts!

Marshfield Cemetery ... VT (1953)

Latest progs depict a multi-day ... contest-worthy event beginning late THU as Gulf of Mexico moisture ascends on SW winds aloft over a modified Arctic air mass migrating east across the northern tier of CONUS.

- Enter your forecast at 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 ... WED ... 02-FEB-22

Verification begins: 12:01 AM EST ... THU ... 03-FEB-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 - Snow Storm #3: 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 Snowfall by Observed Snowfall Scatterplots for Top 4 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 Forecasters

Forecast Skill Score measured against NWS ER WFOs
Positive skill values indicate a forecast/s improvement over the NWS forecasts.
Bias is the arithmetic difference between the average Forecast snowfall and the average of the total Observed snowfall.

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.