Winter '18 / '19 - VCP32: Too Far Apart
Friday, February 22, 2019
Wednesday, February 20, 2019
Winter '18 / '19 - Regular Season Interim Standings: 2
Under the ‘two-thirds’ rule … forecasters who have entered at least THREE forecasts are included in Interim standings #2.
Forecaster statistics for Winter '18 / '19 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.
Tuesday, February 19, 2019
Winter '18 / '19 - Snow Storm #5: Call for Forecasts!
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| Norfolk ... CT 17-FEB-69 |
Call for Forecasts - CANCELLED
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Two separate snow-producing storm systems expected to affect two separate portions of the forecast area over the course of two days.
Each system taken by itself would not qualify as a 'contest-worthy' snow storm but when we cobble them together ... we get just enough stations likely to observe more than a nuisance snowfall to issue a Call for Forecasts.
The forecasting 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" storm-total snowfall.
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Forecast element: each station/s storm-total snowfall
Deadline for entries: 10:00 PM EST ... TUE ... 19-FEB-19
Verification begins: 12:01 AM EST ... WED ... 20-FEB-19
Verification ends: 11:59 PM EST ... THU ... 21-FEB-19
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Enter your forecast at the NEWxSFC/s home page here.
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.
You also get the chance to see how well your forecast stacks up against NWS Eastern Region Weather Forecast Offices (turns out they/ve pretty easy to beat!)
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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).
Monday, February 18, 2019
Sunday, February 17, 2019
Friday, February 15, 2019
Winter '18 / '19 - Snow Storm #4: FINAL Results
http://www.newx-forecasts.com/
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 Best Forecasts
Dotted blue line below (above) solid red line ==> under (over) forecast
Station by Station Comparison of Best Forecasts
Thursday, February 14, 2019
Winter '18 / '19 - Snow Storm #4: Preliminary STP Verification
Preliminary storm-total snowfalls for MON through WED from CDUS41 (CLI) ... CXUS51 (CF6) ... METARs ... and PNS bulletins.
Good coverage and reporting.
No exceptions.
HYA
STP estimated by inverse distance weighting of Barnstable county vicinity reports carried in PNSBOX.
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Stations observing >= Trace - 21 (78%)
Given stations with measurable snowfall; stations observing at least:
4" - 8 (38%)
6" - 4 (19%)
8" - 3 (14%)
10" - 1 (5%)
Max snow melt-water (minimum SLR 10:1)
CAR - 0.87"
BTV - 0.86"
BGR - 0.68"
Max precipitation (frozen + freezing + liquid):
PWM: 1.79"
ACY - 1.71"
BWI - 1.48"
New daily record(s)
13-FEB-19
CAR - 12.9" (8.1"; 2008)
Image courtesy NWS / NCEP /WPC
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Please report any errors in Comments along with a link to the correct data.
FINAL results NLT FRI evening.
Monday, February 11, 2019
Winter '18 / '19 - Snow Storm #4: The Forecasts!
Intern 1
Journey 1
Senior 13
GOVT 1
PWSP -
TOT 17
Forecaster table ranked ascending by storm-total precipitation (STP)
[DOH! My apologies for mis-classifying Forecaster JessicaCain - again - as an 'Intern' when in fact she was promoted to 'Journeyman' this year.]
BLUE ==> 25th percentile.
RED ==> 75th percentile.
WHITE and GREY STP cells range between the 25th and 75th percentile.
Heaviest snowfall (+8") consensus along and to the right of BGR - BTV - CAR - BGR. Lollypop expected at BTV.
Opposite Day on Planet Teleconnections.
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Everyone/s station-by-station forecast at the Contest/s web site.
Direct link to the forecast table.
Sunday, February 10, 2019
Saturday, February 9, 2019
Winter '18 / '19 - Snow Storm #4: Call for Forecasts!
Vertical temperature profiles from numerical weather prediction models suggest the possibility for mixed forms of frozen precipitation i.e., snow and sleet. Verifying storm-total snowfall totals will include sleet accumulations.
The contest for Snow Storm #4 may be cancelled prior to the deadline if fewer than six stations are likely to observe at least a 4" storm-total snowfall.
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Forecast element: each station's storm-total snowfall
Deadline for entries: 10:00 PM EST ... SUN ... 10-FEB-19
Verification begins: 12:01 AM EST ... MON ... 11-FEB-19
Verification ends: 11:59 PM EST ... WED ... 13-FEB-19
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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.
---
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.
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 pretty easy to beat!)
---
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).
Friday, February 8, 2019
Winter '18 / '19 - Regular Season Interim Standings: #1
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 '18 / '19 Regular season snow storm contest 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.
Thursday, February 7, 2019
Sunday, February 3, 2019
Winter '18 / '19 - Season-total Snowfall Forecast Contest: JAN Totals
JAN-19 snowfall summary by Contest forecast station.
Rank ordered descending by percent of monthly period-of-record-normal (P-O-R-N).
Green ==> 75th percentile
White ==> less than 75th and greater than 25th percentile (inter-quartile range)
Red ==> 25th percentile
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JAN Forecast Station Highlights
CAR
Record monthly snowfall (59.8")
Old record: 44.5" (1994)
IAD ... DCA ... BTV
More than double monthly P-O-R-N
Biggest losers
Observed v P-O-R-N
RDU: 0" v 2.5"
ORH: T v 2.9" (2%)
EWR: 0.9" v 8.3" (11%)
BDR: 1.2" v 8.9" (13%)
NYC: 1.1" v 7.5" (15%)
PVD: 1.6" v 10.2" (16%)
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Season-to-Date
On average ... JAN contributes 275.6" (30%) toward the season-total snowfall (D-J-F-M) of 914".
JAN-19 observed snowfall: 296.3" (32% of season-total snowfall)
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Teleconnection indexes and month-over tendency (updated as they become available)
AO:
NAO:
PDO:
QBO
SOI:
⇩⇧
Saturday, February 2, 2019
Winter '18 / '19 - Snow Storm #3: FINAL Results
Forecasters' station verifications and the storm summary available at NEWxSFC/s home page.
http://www.newx-forecasts.com/
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
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