CONTEST STATUS - Updated: WED ... 21-FEB-19 @ 8:35 PM EST

Winter '17 / '18 - Snowfall Forecast Contests
19th Annual 'Regular Season'
- Interim Standings ... as of Snow Storm #4 here
- Forecaster Storm Stats ... as of Snow Storm #5 here

- Snow Storm #5: 17-FEB-18
FINAL Results here

- Snow Storm #4: 07-FEB-18
FINAL Results here

17th Annual 'Season-total'
Deadline for entries has passed
Forecasters' summary here

----------------------------------------------------
Winter '16 / '17 - Snowfall Forecast Contests
----------------------------------------------------
18th Annual 'Regular Season'
FINAL results here

---
16th Annual 'Season-total'
FINAL results here

Tuesday, February 20, 2018

Winter '17 / '18 - Snow Storm #5: FINAL Results

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

     
 1st - HWSNBN 
 SUMSQ:63  
 SUMSQ Z:-1.524  
 STP:5.2 (4) 
 TAE:29.9 (1) 
 AAE:1.30 (1) 
     
 2nd - NWS ER WFOs   
 SUMSQ:73  
 SUMSQ Z:-1.062  
 STP:5.8 (5) 
 TAE:30.4 (2) 
 AAE:1.32 (2) 
     
 3rd - donsutherland1   
 SUMSQ:84  
 SUMSQ Z:-0.630  
 STP:8.6 (8) 
 TAE:33.0 (6) 
 AAE:1.43 (6) 
     
 HM - Brad Yehl   
 SUMSQ:86  
 SUMSQ Z:-0.538  
 STP:30.8 (12) 
 TAE:32.9 (5) 
 AAE:1.43 (5) 
     

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

Monday, February 19, 2018

Winter '17 / '18 - Snow Storm #5: Preliminary STP Verifications

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

Exceptions:
PWM / CON
17-FEB CLI and CF6 bulletins carried 'MM'.
STP based on ASOS reports carried in PNSGYX.

HYA
METARs and vicinity reports carried in PNSBOX.

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 - 23 (85%)
4" - 8 (35%)
6" - 4 (17%)
8" - 0

Melt-water
ORH - 0.54"
PWM - 0.53"
BOS - 0.52"

New daily records:
None

Surface analysis:  03z ... 18-FEB-18
   
---
Please report errors in Comments along with a link to the correct data.
FINAL Results post expected TUE evening ... 20-FEB-18

Saturday, February 17, 2018

Winter '17 / '18 - Snow Storm #5: The Forecasts!

Rookie   -
Intern   1
Journey  -
Senior   9
GOVT    1
PWSP    1
TOT  12

All forecasts posted to the Contest/s web site.
http://www.newx-forecasts.com/NEWxSFC_19/storms/storm5_forecasts_17Feb18.htm
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) and PWSP (Private Weather Service Provider) forecasts derived from public issuances current at the deadline.

Heaviest snowfall (>= 4") consensus along and to the right of BOS - PVD - BDR - BDL - ORH - BOS with an isolated action center INVOF ABE.  Snow cone expected at PVD.

Tele-connection indexes (sigh).  AO racing to catch the bus (or not).

Median station forecasts (Power Map - Excel 2013)

Friday, February 16, 2018

Winter '17 / '18 - Snow Storm #5: RAW FORECASTS

Here

Winter '17 / '18 - Snow Storm #5: Call for Forecasts

Apologies for the truncated notice.

Sad looking area of LOW pressure progged to ride the STJ into the forecast area on SAT and lay down a stripe of frozen precipitation along the NW edge of the precipitation shield as it deepens off the SNE coast near the 40/70 benchmark.

Synoptics seem all wrong for a contest-worthy snow storm but hate to be left at the alter this late in the season after seeing the broad brush of plowable snow forecast currently by ER WFOs.

Whatever happened to those blockbuster nor'easters around Presidents Day?

The forecast contest for Snow Storm #5 may be cancelled prior to the deadline if fewer than six stations are likely to observe at least a 4" snowfall.

---
Forecast element:  each station's verification period snowfall
Deadline for entries:  10:30 PM EST ... FRI ... 16-FEB-18
Verification period begins:  12:01 AM EST ... SAT ... 17-FEB-18
Verification period ends:  11:59 PM EST ... SUN ... 18-FEB-18

---
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.

---
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.

---
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).

Wednesday, February 14, 2018

Winter '17 / '18 - Regular Season Interim Standings: 2

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



Complete interim statistics table and charts 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.

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

Saturday, February 10, 2018

Winter '17 / '18 - Snow Storm #4: FINAL Results

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

     
 1st - Herb @MAWS   
 SUMSQ:26  
 SUMSQ Z:-0.729  
 STP:16.8 (4) 
 TAE:17.3 (1) 
 AAE:0.82 (1) 
     
 2nd - donsutherland1   
 SUMSQ:29  
 SUMSQ Z:-0.682  
 STP:18.7 (5) 
 TAE:19.0 (2) 
 AAE:1.00 (3) 
     
 3rd - iralibov   
 SUMSQ:38  
 SUMSQ Z:-0.527  
 STP:22.3 (8) 
 TAE:22.3 (5) 
 AAE:1.01 (4) 
     
 HM - Mitchel Volk   
 SUMSQ:39  
 SUMSQ Z:-0.515  
 STP:16.4 (3) 
 TAE:20.2 (3) 
 AAE:0.96 (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

Friday, February 9, 2018

Winter '17 / '18 - Snow Storm #4: 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

HYA - Trace
METAR KHYA 080656Z AUTO 33012G19KT 10SM BKN021 OVC085 02/M01 A2996 RMK AO2 RAE03UPB16E19SNB03E16

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

9 minutes heavy sleet event @ ALB
METAR KALB 072109Z 35009KT 1SM R01/6000VP6000FT +PL BR BKN007 OVC010 M06/M08 A2993

---
Stations observing at least:
Trace - 19 (70%)
4" - 7 (37%)
6" - 5 (27%)
8" - 0

Melt-water
BGR - 0.53"
BGM - 0.52"
CAR - 0.52"

New daily records:
None

Surface analysis:  18z ... 07-FEB-18
  
---
Please report errors in Comments along with a link to the correct data.
FINAL Results post expected ~11 PM EST ... SAT ... 10-FEB-18

Thursday, February 8, 2018

Winter '17 / '18 - Sudden Stratospheric Warming: Watch #1 - Update 1

Full reversal at D+5 (12-FEB) comports very well with the earlier D+10 forecast.
 
Full reversal continues at least through D+10.
Huge implications for the weather associated typically with a negative Arctic Oscillation toward month's end and into MAR.
 
 
Where the AO/s full impact is wrt arctic/s cold air drainage appears to be on the other side of the globe under the 'W' ; however ... note the NW flow regime and +PNA is progged over CONUS.

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

Station snowfall summary for JAN-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:  -0.281⇩
NAO:  1.44⇧
PDO:  0.70⇧
QBO:  -19.02⇩
SOI:  8.9⇧