Thursday, January 03, 2008

Contest # 4 - Final Results

NEWxSFC/s perennial bridesmaid Shanabe (aka SYRMAX) finally made it to the alter of Contest #4 and crushed the field in doing so by verifying with a SUMSQ error score 47% better than the average error. His winning forecast accounted for 95% of the observed snowfall/s variability.

Shanabe hit the trifecta finishing first in Total Absolute Error (11.6") and Average Absolute Error (0.48"). His STP forecast error of 8.26" was good for second place.

Congratulations...Shanabe!

Full forecast verifications and contest summary @ the web site.

Contest # 4 - Teleconnections

Sharp drop in AO ahead of the storm associated with big push of arctic air into CONUS/ eastern half. PNA swung the distance of one STD from negative to positive along with a near-normal NAO moving into higher territory.

Favorable PNA and AO conditions produced MAX snowfall @ contest stations that were the lowest of the four snow storms to date.

Contest # 4 - Verification

Preliminary storm-total snowfalls from CDUS41 and CF6 bulletins for Tuesday and Wednesday.

BGR amount is suspect given PNS reports of 9 - 10" SE of the station on the coast and 10 - 12" 7 - 10 miles to the N.

New daily records
None


Final results and storm summary on Friday.
Please report errors in 'Remarks.'

Wednesday, January 02, 2008

Interim Standings

After three snow storms...donsutherland1 is in 1st Place with a hefty lead.

Click to enlarge

SUMSQ errors are normalized with a 'Z-score' for each snow storm contest...then averaged to compute the standings. Forecasters who have entered at least 2/3 of all snow storm contests are included in the standings.

If a forecaster has participated in more than two-thirds of all snow storm contests...then Z-scores from their 'best two-thirds' forecasts are used to calculate interim and final standings. Same idea as dropping the lowest quiz score before computing the final grade.

Contest # 3 - Final Results

Chief Forecaster Donsutherland1 finished in 1st place for contest snow storm #3. This is his second 1st place finish this year.

No only did he have the lowest SUMSQ error...he hit the trifecta with top honors for Total Absolute Error (30% improvement over Consensus) and Average Absolute Error (1.16").

Donsutherland1/s STP forecast for 60" had an error of 0.95" (total observed snowfall @ all stations less total forecast snowfall @ all stations). The R-square statistic of 0.837 shows his forecast accounted for 84% of the observed snowfall/s variability.

Congratulations...Don!

Full forecast verification and contest summary @ the web site.

Tuesday, January 01, 2008

Mild...Then Wild





Despite some disagreement among the ENSM members...teleconnection indice forecasts suggest movement toward a colder...stormier planetary flow regime for the EC around mid-JAN following a brief spell of mild wx.





Today/s GooFuS depicts a series of SE PAC cyclones coming ashore then migrating NE through the central CONUS...blocked from coming too far E by the stubborn SE heat ridge through D+8. The extended range progs create a hi-amplitude ridge W that allows intense arctic anticyclones back into the Lower 48.


When the cold returns...so do the EC storms.

Snowfall Summary - DEC '07

Bonus snows were observed over much of the Northeast in December...with some stations getting up to three and half times their period-of-record normal (PORN) amounts.

BOS snowfall of 27.7" was 360% PORN (7.7") and amounts to 68% of D-J-F-M PORN (41").
CON snowfall of 44.5" is 78% of their D-J-F-M PORN (57.3"). DEC normally contributes 24% of the CON/s season-total snowfall and 19% @ BOS.

Most stations...where DEC snowfall was well in excess of PORN...also observed below normal temperatures. BGR had the greatest departure of -4°F. The exception was ACY where DEC/s snowfall of 4.4" was 183% of PORN and temperatures were 1.7°F above normal.

RED ==> Top 25%
BLUE ==> Bottom 25%
White ==> everywhere in between

Contest # 3 - Verification

Preliminary storm-total snowfalls from CDUS41 and CF6 bulletins for Sunday and Monday.

SN-to-H2O ratio for MDT is estimated.

Minor discrepancy between amounts reported by 12/30 CDUS41 (0.9") and F6 (0.3") @ PWM.

CAR amount is suspect given its 10:1 ratio and the vertical temperature profile during the event; however..VCNTY PNS reports suggest 3.4" is likely correct.

New daily records
12/31
BGR - 8.2" (6.4"; 1972)
CON - 10.1" (6"; 1879)
PWM - 6.6" (4.3"; 1893)
ALB - 7.9" (6.4"; ?)

Final results and storm summary on Wednesday.
Please report errors in 'Remarks.'

Monday, December 31, 2007

Contest # 4 - The Forecasts

Maximum...average...median...and minimum station forecasts

Seven veteran forecasters. No rookies who must all be out partying tonight.

MAX STP: jackzig 61.25"
MIN STP: TQ 42.45"
AVG STP: 53.50"

Another northern New England event where the consensus heavy snowfall axis is expected from CAR - BGR - PWM - CON - BTV - CAR.

All forecasts have been posted to the NEWxSFC web site. Follow the link from Storm Contest Forecasts 'Contest # 4'. Forecasts are ranked from minimum to maximum STP.

Contest # 3 - Teleconnections

Heavy snows fell across northern portions of the forecast area...yet so-called 'critical heavy snowfall' teleconnection indices are all on the wrong side of zero for this event.

Not surprising. It/s another meteorological myth that can/t stand the light of data.