Winter '17 / '18 - 17th Annual 'Season-total' Snowfall Forecast Contest: FINAL Results

UPDATE 2:  10:45 PM EDT ... FRI ... 06-APR-18

All better (I hope)

 

UPDATE:  10:15 PM EDT ... FRI ... 06-APR-18

Senior NEWxSFC forecaster Roger Smith was inadvertently omitted from the FINAL Results summary (operator error - Excel copy down mistake).  Fix in the works

 

 h/t Roger 'Eagle Eye' Smith

 

--- 

 

 Complete station-by-station forecaster verifications at the Contest/s web site here (direct link)

Perfect forecasts
iralibov @ PVD (47")

Near misses (< 1" error)
Mitchel Volk
0.1" @ ALB (74.9")
0.2" @ PHL (29.8")
0.2" @ ORF (15.2")
0.3" @ CON (85.3")
0.4" @ NYC (35.4")

Any.wx
0.1" @ BDR (39.9")
0.5" @ BTV (81.5")

33andrain
0.1" @ IAD (11.9")
0.6" @ BOS (58.6")

iralibov
0.1" @ RDU (8.9)
0.6" @ BOS (58.6")

kevinmyatt
0.4" @ NYC (35.4")
0.4" @ RIC (12.4")

Brad Yehl
0.2" @ BDL (48.4")

donsutherland1
0.6" @ EWR (34.4")

MarkHofmann
0.8" @ DCA (7.8")

Smallest station forecast error yet percent error >= 10%
Mitchel Volk
11.1" @ PWM (91.1")
2.2" @ SBY (17.2")

TQ
11.1" @ PWM (91.1")

Any.Wx
11.1" @ PWM (91.1")

donsutherland1
16.5" @ BGR (109")

33andrain
8.9" @ ORH (88.9")

iralibov
10.2" @ ACY (34.2")

Roger Smith
2.2" @ SBY (17.2")

snocat918
1.6" @ BWI (15.4")

MarkHofmann
0.8" @ DCA (7.8")

---

Season-total snowfall from all stations (1,234") came in 35% above the period-of-record normal (914").  Winter '17 / '18 ranks 4th among other Contest years since winter '04 / '05 ... the season when BGR and BGM were added to the station list.

Winter '17 / '18 - 17th Annual Season-total Snowfall Forecast Contest: Observed Snowfall Station Summary

Bonus snows for 84% of forecast stations.

 

RED: <= 25th percentile
WHITE: > 25th and < 75th percentile
GREEN: >= 75th percentile

Winter '17 / '18 monthly snow totals
DEC:  http://newxsfc.blogspot.com/2018/01/winter-17-18-season-total-snowfall.html
JAN:  http://newxsfc.blogspot.com/2018/02/winter-17-18-season-total-snowfall.html
FEB:  http://newxsfc.blogspot.com/2018/03/winter-17-18-season-total-snowfall.html
MAR:  http://newxsfc.blogspot.com/2018/04/winter-17-18-season-total-snowfall.html

Winter '17 / '18 - Coastal Teaser #4

UPDATE 2:  9 AM EDT FRI ... 06-APR-18
Not happenin'

---
UPDATE:  7:30 PM EDT THU ... 05-APR-18
Not lookin'good.
Maybe a nice surprise lurks in the overnight runs.

Possible 'Call for Forecasts' in the AM.

---
Snow Storm #9?

Should the present NWP trend continue ...
Call for Forecasts:  THU ... 05-APR-18
Deadline for entries:  10:30 PM EDT ... FRI ... 06-APR-18
Verification period:  12:01 AM EST ... SAT ... 07-APR-18 till TBD

Watch this space.

Winter '17 / '18 - Season-total Snowfall Forecast Contest: MAR totals

Station snowfall summary for MAR-18.
Rank ordered by percent of monthly normal.

---
Green ==> 75th - 100th percentile
White ==> Less than 75th and greater than 25th percentile
Red ==> 0 - 25th percentile

---
Teleconnection indexes and month-over trend (updated as they become available)
AO:  -0.941⇩
NAO:  -0.93⇩
PDO:  -0.05⇩
QBO:  -19.77⇩
SOI:  10.5⇧

Winter '17 / '18 - Snow Storm #7: NESIS

CAT 2
NESIS 3.15

Winter '17 / '18 - Coastal Teaser: #3

UPDATE:
SAT ... 31-MAR-18 @ 10 PM EDT

Nothing contest-worthy about this event ATTM.

Slightest chance the 00z ... 01-APR-18 NWP runs will suggest otherwise ==> possible SUN AM  'Call for Forecasts'.

---
Snow Storm #9?

Should the present NWP trend continue ...
Call for Forecasts:  SAT ... 31-MAR-18
Deadline for entries:  10:30 PM EDT ... SUN ... 01-APR-18
Verification period:  12:01 AM EST ... MON ... 02-APR-18 till TBD

Watch this space.

Winter '17 / '18 - Regular Season Interim Standings: 6

Under the ‘two-thirds’ rule … forecasters who have entered at least SIX forecasts are included in interim standings #6.

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)

 ---
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.

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

Winter '17 / '18 - Snow Storm #8: FINAL Results

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

	1st - Brad Yehl
	SUMSQ:	278
	SUMSQ Z:	-1.279
	STP:	28.9	(3)
	TAE:	65.1	(1)
	AAE:	2.50	(1)
	2nd - Shillelagh
	SUMSQ:	380
	SUMSQ Z:	-0.845
	STP:	43.4	(5)
	TAE:	73.7	(2)
	AAE:	2.95	(2)
	3rd - donsutherland1
	SUMSQ:	483
	SUMSQ Z:	-0.408
	STP:	64.9	(9)
	TAE:	90.3	(5)
	AAE:	3.34	(4)
	HM - iralibov
	SUMSQ:	489
	SUMSQ Z:	-0.383
	STP:	60.1	(7)
	TAE:	87.3	(3)
	AAE:	3.23	(3)

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
Dotted blue line below (above) solid red line ==> under (over) forecast

Station by Station Comparison of Top Forecasters

Winter '17 / '18 - Snow Storm #8: Preliminary STP Verifications

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.

---
Stations observing at least Trace - 24 (89%) [corrected]

Given a forecast station observed measurable snowfall ...
Stations observing at least:
4" - 10 (42%)
8" - 5 (21%)
12" - 2 (8%)
16" - 1 (4)

Melt-water
ISP - 1.28"
MDT - 1.13"
PHL - 1.03"
JFK - 0.91"

Max precipitation:  ISP - 1.28"

New daily records:
21-MAR-18 (7)
ISP - 14" (1.8"; 2013)
ABE - 13.2" (4.3"; 1964)
MDT - 11.9" (7.5"; 1964)
JFK - 8.4" (0.8"; 1993)
EWR - 7.9" (5.3"; 1958)
PHL - 6.7" (4.7"; 1932)
IAD - 4.8" (2.3"; 1964)

22-MAR-18 (1)
ISP - 4.4" (3"; 1992)

SFC analysis:  03z ... 22-MAR-18

METAR KISP 220256Z 01017G28KT 1/8SM R06/2000V3000FT +SN FG VV003 00/00 A2964 RMK
AO2 PK WND 03033/0231 SLP036 ==> SNINCR 5/12 <== P0023 60040 T00000000 51001 =

5" / hour!

---
Please report errors in Comments along with a link to the correct data.
FINAL Results post expected SAT evening ... 24-MAR-18

Winter '17 / '18 - Regular Season Interim Standings: 5

Under the ‘two-thirds’ rule … forecasters who have entered at least FIVE 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)

---
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.

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