Sunday, January 16, 2022

Winter '21 / '22 - Snow Storm #2: The Forecasts!

BWI
13-DEC-60

Rookie      2
Intern      1
Journey      -
Senior      12
GOVT      1
PWSP      1
TOT      17

Forecaster table ranked by ascending storm-total precipitation (STP)

BLUE ==> 1st quartile
RED ==> 4th quartile
WHITE and GREY STP cells range between the 1st and 4th quartiles.

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

PNA making a half-hearted effort but NAO and AO just not that interested.


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

Saturday, January 15, 2022

Winter '21 / '22 - Snow Storm #2: RAW Forecasts

 

NYC
12-27-47
click through for the listing ...

Friday, January 14, 2022

Winter '21 / '22 - Snow Storm #2: Call for Forecasts!

HRW FV3 54-hr Forecast Valid 1 PM EST ... SUN ... 16-JAN-22
The long awaited and much anticipated mid-latitude cyclone arrives on the east coast SUN toting a steamer trunk brimming with mixed precipitation.  More than enough forecast stations for a contest-worthy snow storm.

- Enter your forecast at the 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 ... SAT ... 15-JAN-22
Verification begins: 12:01 AM EST ... SUN ... 16-JAN-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!

Thursday, January 13, 2022

Winter '21 / '22 - Coastal Teaser #2

 

Worst kept secret evah ...

Snow Storm #2 all but certain to affect most if not all forecast stations SUN into MON.  NWP models tease for a yuge event of mixed precipitation types makes for a challenging forecast.

Call for Forecasts likely FRI.

Deadline for entries would be 10 PM EST ... SAT ... 15-JAN-22


Sunday, January 09, 2022

Winter '21 / '22 - Snow Storm #1: 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 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 Forecasters

Saturday, January 08, 2022

Winter '21 / '22 - Snow Storm #1: Preliminary STP Verification

Accumulation-weighted SN:H20 (SLR)

UPDATE 1/8 @ 1:15 PM EST:  fixed snow totals for IAD ... BGM.  Thanks to 'anonymous' in comments for the eagle-eye. 

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

HYA
STP estimated from one report carried by BOSPNS within 2.2 SM of the station.  Station did not carry 6-and 7-group data.

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:  25 (93%)
Given stations with measurable snowfall ... stations observing at least:
4" - 14 (42%)
6" - 5 (19%)
8" - 2 (7%)

Max snow melt-water (minimum SLR 10:1)
ORH: 0.52"
BOS:  0.48"
BDL:  0.44"

Max precipitation (frozen + freezing + liquid):
ORH: 0.52"
BOS:  0.48"
BDL:  0.44"

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New daily record(s)
None

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Storm total snowfall
Image courtesy NOHRSC

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SFC analysis:  09z ... 07-JAN-21
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 SUN evening.

Friday, January 07, 2022

Winter '21 / '22 - Snow Storm #1: The Forecasts!

Central Park - NYC 09-JAN-1941
Central Park - NYC
09-JAN-1944


Rookie      -
Intern      1
Journey      -
Senior      10
GOVT      1
PWSP      1
TOT      13

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Forecasters rank-ordered by ascending storm-total precipitation (STP)

BLUE ==> 1st quartile
RED ==> 4th quartile
WHITE STP cells fall between the 1st and 4th quartiles


Heaviest snowfall (+5") consensus along and to the right of a line from BOS - PVD - ISP - ORH - BOS.  Lollypop expected at BOS (6.4")

Teleconnections (AO ... NAO ... PNA) unavailable since 05-JAN-22.

Forecasters' station-by-station forecasts posted to the Contest/s web site here.
http://www.newx-forecasts.com/

Direct link to the table of forecasts here.
http://www.newx-forecasts.com/NEWxSFC_23/storms/storm1_forecasts_07JAN22.htm

Thursday, January 06, 2022

Wednesday, January 05, 2022

Winter '21 / '22 - Snow Storm #1: Call for Forecasts!

An initially flat ... open shortwave in fast moving semi-zonal flow offers an opportunity for the first snowfall forecasting contest of Winter '21 / '22.  

On a more optimistic note:  NWP expects the shortwave to amplify as it reaches the coast.

While the progs aren/t offering much hope for a contest-worthy snow storm ... the latest NWS WFO point forecasts issued by BOX ... GYX ... and CAR point to at least six stations more than a nuisance snowfall (>= 4") could be observed.

NOTE:  snowfall expected to begin over southern interior stations before the 10 PM EST deadline.  Forecasts should include amounts observed on THU.  This is non-standard verification period driven by events (verification usually begins a few hours after the deadline at the start of the next day).

The forecasting contest for Snow Storm #1 may be cancelled prior to the deadline if at least six-to-eight stations seem unlikely to observe at least a 4" storm-total snowfall.

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Enter your forecast at the 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 ... THU ... 06-JAN-22
Verification begins: 12:01 AM EST ... THU ... 06-JAN-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!

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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).

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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.

Tuesday, January 04, 2022

Winter '21 / '22 - Coastal Teaser #1


Hot on the heels of the 03-JAN snow storm comes the chance for a contest-worthy nor'easter and the first snowfall forecasting contest of the '21 / '22 winter.

Progs currently advertising cyclogenesis along the trailing end of an arctic cold frontal boundary draped across the central Gulf coast states attended by a negatively-tilted trough aligned along the MS river valley THU AM with snow beginning over the forecast area early FRI AM.

A 'Call for Forecast' would be issued WED evening with a deadline for entries @ 10 PM EST ... THU ... 06-DEC-22 should current model trends continue.