NE.Wx Snowfall Forecast Contests

Saturday, March 17, 2018

Winter '17 / '18 - Snow Storm #7: FINAL Results

Forecasters' station verifications and the storm summary at NEWxSFC/s home page.
http://www.newx-forecasts.com/


1st - iralibov
SUMSQ:	328
SUMSQ Z:	-1.379
STP:	31.6	(5)
TAE:	66.3	(1)
AAE:	2.46	(1)

2nd - donsutherland1
SUMSQ:	365
SUMSQ Z:	-1.041
STP:	29.7	(2)
TAE:	67.0	(2)
AAE:	2.48	(2)

3rd - TQ
SUMSQ:	394
SUMSQ Z:	-0.787
STP:	47.5	(8)
TAE:	75.0	(4)
AAE:	2.78	(4)

HM - Brad Yehl
SUMSQ:	400
SUMSQ Z:	-0.735
STP:	45.8	(7)
TAE:	67.8	(3)
AAE:	2.51	(3)

SUMSQ: sum of square errors (")
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
Dotted blue line below (above) solid red line ==> under (over) forecast

Snowfall analysis courtesy National Operational Hydrologic Remote Sensing Center
http://www.nohrsc.noaa.gov/interactive/html/map.html

Friday, March 16, 2018

Winter '17 / '18 - Snow Storm #7: Preliminary STP Verifications

by TQ @ 7:33 PM

Table of preliminary storm-total snowfall by station for WED and THU from CDUS41 (CLI) ... CXUS51 (CF6) and ... SAUS41 (METAR) bulletins.

Exceptions: none

SLR not available for some stations reporting measureable snowfall b/c liquid and / or freezing precipitation also occurred during the verification period.

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Stations observing at least:
Trace - 27 (100%)
4" - 14 (52%)
8" - 10 (37%)
12" - 6 (22%)
16" - 3 (11)
20" - 2 (7%)

Melt-water
ORH - 1.6"
PWM - 1.28"
BTV - 1.19"
BGR, BOS - 1.16"

Max precipitation: ORH - 1.6"

New daily records: 13-MAR-18
ORH - 21.8" (14.8"; 1993)
BOS - 14.5" (12.3"; 1993)
PVD - 9.5" (7"; 1993)

SFC analysis: 15z ... 13-MAR-18

13-MAR-93: the last Storm of the Century for the 20th century.

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Please report errors in Comments along with a link to the correct data.
FINAL Results post expected SAT evening ... 17-MAR-18

Thursday, March 15, 2018

Winter '17 / '18 - Regular Season Interim Standings: 4

by TQ @ 7:45 PM

Under the ‘two-thirds’ rule … forecasters who have entered at least FOUR forecasts are included in the interim standings.

Complete interim statistics table and chart at the Contest/s web site here (direct link)
Forecaster statistics for Winter '17 / '18 contest snow storms here (direct link)

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SUMSQ errors for each contest snow storm are normalized (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.

Same idea as dropping the lowest quiz score before computing the final grade.

Wednesday, March 14, 2018

Winter '17 / '18 - Snow Storm #6: NESIS

by TQ @ 7:18 PM

CAT 2
NESIS 3.45

inter '17 / '18 - Snow Storm #2: NESIS

by TQ @ 7:15 PM

CAT 1
NESIS 1.71

Monday, March 12, 2018

Winter '17 / '18 - Snow Storm #7: The Forecasts!

by TQ @ 7:39 PM

UPDATE: 17-MAR-18 @ 12:40 PM EDT
Corrected 'Consensus Forecasts and Extremes' chart.

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Rookie -
Intern 1
Journey -
Senior 8
GOVT 1
PWSP -
TOT 10

All forecasts posted to the Contest/s web site. (direct link)

Forecasts ranked by their verification period storm-total precipitation (STP).
BLUE = 25th percentile
RED >= 75th percentile
White STP and 4cast cells range between the 25th and 75th percentile

NWS ER WFOs (GOVT) forecasts derived from public issuances current at the deadline.

Heaviest snowfall (>= 12") consensus along and to the right of CAR - BGR - PWM - BOS - PVD - ORH - PWM - CAR. Snow cone expected at BGR.

AO FTW! (again).

Sunday, March 11, 2018

Winter '17 / '18 - Snow Storm #7: RAW FORECASTS

by TQ @ 10:41 PM

Here

Winter '17 / '18 - Snow Storm #6: FINAL Results

by TQ @ 1:16 PM

Forecasters' station verifications and the storm summary at NEWxSFC/s home page.
http://www.newx-forecasts.com/


1st - Donald Rosenfeld
SUMSQ:	200
SUMSQ Z:	-1.171
STP:	16.1	(8)
TAE:	53.2	(1)
AAE:	2.22	(1)

2nd - Herb @MAWS
SUMSQ:	220
SUMSQ Z:	-1.005
STP:	4.7	(4)
TAE:	53.3	(2)
AAE:	2.32	(3)

3rd - NWS ER WFOs
SUMSQ:	249
SUMSQ Z:	-0.772
STP:	11.1	(6)
TAE:	56.4	(3)
AAE:	2.45	(5)

HM - Roger Smith
SUMSQ:	253
SUMSQ Z:	-0.745
STP:	22.9	(10)
TAE:	58.4	(5)
AAE:	2.24	(2)

SUMSQ: sum of square errors (")
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
Dotted blue line below (above) solid red line ==> under (over) forecast

Snowfall analysis courtesy National Operational Hydrologic Remote Sensing Center
http://www.nohrsc.noaa.gov/interactive/html/map.html

Saturday, March 10, 2018

Winter '17 / '18 - Snow Storm #7: Call for Forecasts!

by TQ @ 8:32 PM

UPDATE: 3:30 PM EDT SUN ... 11-MAR-18
Deadline: 10:30 PM EDT SUN ... 11-MAR-18 (as advertised)

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Meh. Our fortunes have faded with each model run.
Consider this 'Call for Forecasts' a marker just in case the storm develops into something contest-worthy.

13-MAR-1888

The deadline for entries could slip to MON evening if the main event appears more likely to affect northern forecast stations beginning TUE rather than those in the south on MON. Watch this space.

The forecast contest for Snow Storm #7 may be cancelled prior to the deadline if fewer than six stations are likely to observe at least a 4" snowfall.

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Forecast element: each station's verification period snowfall

Deadline for entries: 10:30 PM EDT ... SUN ... 11-MAR-18
Verification period begins: 12:01 AM EDT ... MON ... 12-MAR-18
Verification period ends: when snow associated with the primary storm ends

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Enter your forecast at the NEWxSFC/s home page here. 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. See how well your forecast stacks up against NWS Eastern Region Weather Forecast Offices.

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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).

NEWxSFC/s email client is permanently off-line.
Forecasters will no longer have a copy of their forecast emailed to them.
Apologies for the degraded service which is beyond my control.

Winter '17 / '18 - Snow Storm #6: Preliminary STP Verifications

by TQ @ 3:05 PM

Table of preliminary storm-total snowfall by station for WED through FRI from CDUS41 (CLI) ... CXUS51 (CF6) and ... SAUS41 (METAR) bulletins.

Exceptions:
HYA
METARs indicate Trace amount

SLR not available for some stations reporting measureable snowfall b/c liquid and / or freezing precipitation also occurred during the verification period.

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Stations observing at least:
Trace - 23 (85%)
4" - 13 (57%)
8" - 8 (35%)
12" - 3 (13%)
16" - 1 (4%)

Melt-water
PWM - 1.38"
ORH - 0.99"
PWM - 0.98"

Max precipitation: ACY - 2.11"

New daily records: 5
ISP - 6.5" (2"; 2013)
PHL - 6" (4"; 1969)
BDR - 6" (1.2"; 1969)
EWR - 4.6" (2.3"; 1969)
JFK - 2.8" (1.7"; 1969)