Contest # 1 - Teleconnections

Sharp decline in AO and NAO the right before the storm day. Small rise in otherwise flat / negative PNA.

Near-simultaneous drop in AO / NAO and rise in PNA reflect L/W amplification associated with the storm.

Contest # 1 - The Forecasts

(updated below)

Click to Enlarge
Sixteen Fifteen forecasters...one rookie...and one late entry pending approval

Storm Total Precipitation (STP) forecasts range from a low of 55.7" (smadsen8486) to a high of 108" (Mitchel Volk).

Average STP is 78.9"

Clearly a northern New England event...where the consensus heavy snow axis (+6") extends from BTV - CAR - BGR - PWM - CON - BTV.

All individual forecasts have been posted to the NEWxSFC web site. Follow the link to 'Contest # 1 - The Forecasts'. The forecasts are ranked from minimum to maximum STP for all stations.

UPDATE: The 16th entry was disqualified b/c the forecaster took into account model data not available to other forecasters who entered on deadline.

The forecasts posted on the web site will be updated during verification.

Contest # 1 - Call for Forecasts

Hot on the heels of the ‘season-total’ contest deadline…the first storm of the new ‘individual storm’ season is progged to affect a good portion of the forecast area Sunday through early Tuesday. We/re off to a good start compared to last year when the first contest storm didn/t happen until February.14.

Deadline: 10:30 PM EST Saturday, 01 December 2007
Forecast verification begins: 12:01 AM EST Sunday, 02 December 2007

Forecasts must be entered via the Contest/s web site
Follow the link to 'Enter Storm Forecast.'

Forecasters need to register once before entering…even if they were registered last year.

Registration is simple… requiring only a user name and password. If you provide a valid e-mail address…a copy of your forecast will be sent to you. Please ensure your browser is enabled to accept first-party cookies.

All forecasts will be posted to the NE_Wx Google Group by the Contest Administrator before 11 PM EST Saturday, 01 December 2007 and to the Contest web site by Sunday evening.

More information about the contest/s rules…forecast verification…and scoring can be found at the main web site.

Updates and announcement are posted on the Contest/s web log

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Contest subject to cancellation before the deadline, if forecast conditions warrant.

Each contest must have a minimum of seven forecasters for the results to be included in the end-of-season scoring.

Please enter 0.05 for trace amounts instead of a 'T.' if no snow is expected at a station, please do not enter a zero, just leave it blank, instead.

The NE.Wx Snowfall Forecast Contest (NEWxSFC) is a multi-month event that continues into late March or early April. In general, contests are held whenever a decent, synoptic-scale storm rears its head and threatens at least a half-dozen forecast stations with more than nuisance snowfall amounts. Forecasters are called to post their 'storm total' snowfall predictions, on deadline, for 27 NWS / FAA observing stations scattered about New England and the Mid-Atlantic regions. The Contest Administrator determines the deadlines for entries; verifies all forecasts, and publishes the final results to the Contest/s web site.

Please be sure to read the rules before entering the contest b/c your entry constitutes agreement to abide by them.

You can find the Contest Rules and additional information about Error Scoring, current monthly snowfall climatology from NCDC, daily CPC teleconnection indices, daily NESDIS N-Hemi snow cover, and NWS Daily Climate Bulletins (CDUS41) by pointing your browser @ www.newx-forecasts.com

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The Retro Heat Ridge

Today/s D+10 ECMWF and GooFuS progs have kissed and made up following their recent spate of dissonant solns regarding the evolution of a La Nina-style heat-ridge parked over the SW ATL Ocean. Also note the hi-latitude block indicative of a strong negative phase of the Arctic Oscillation.


Should be good and chilly in the E and with the full latitude trof...good baroclinicity and opportunities for coastal storms.



There/s been talk of late in some 'well respected' quarters about a mid-month return to warmth -- as in 'abnormally warm' warmth -- when the full fx of La Nina become firmly established. It/s hard to see where that/s indicated or even remotely suggested if the D+10 and D+15 GFS ensemble means are to be believed.

Folklore - December

A green Christmas; a white Easter.

If there's thunder during Christmas week...
The Winter will be anything but meek.

The nearer the New Moon to Christmas Day...the harder the Winter.

If Christmas day be bright and clear
There’ll be two winters in the year.

Thunder in December presages fine weather.

Like in December like all the year long.

Winter '07 / '08 - What Is It About Week One?

Is there something special about the first week in December or is it merely a case of undue importance being placed on more recent events that makes it seem that way?

Questions about Week One/s seemingly 'stormy nature' have been raised b/c GooFuS LR solutions...as they/re wont to do now that winter grand entrance is waiting in the wings...have again begun dangling shiny objects before our eyes.

The first week of DEC has been a good period for snow storms in the NE the past half-decade. The table shows the number of contest stations reporting snow by year and day of week.

The only other period since 1948 where the first week of DEC was that active - defined as number of stations affected - was between 1954 and 1958.

CAR and BGM have the best chance (20 - 30%) of a measurable snowfall on any day during Week One. BGR has a 20% probability on three of the seven days.

As November 21st...so the winter

If that/s the case...then this winter will hew closely to the CW for 'above normal' temperatures...especially in SNE and the M-A.

A few stations in the NE were below normal yesterday. BGR - PWM - BOS - BDL - CON had departures from -1 to -3°F...due in large part to low overcast and light rain.

Elsewhere...
+1 to +4°F: CAR - BTV - PVD - BDR - ISP - JFK - EWR
+7 to +10°F: ALB - ABE - MDT - PHL
+12 to +20°: ACY - SBY - RIC - RDU - IAD - DCA - BWI

IAD took top honors at +20°F.

ECHAM/s October Outlook - Verification

Appears to be a miss grande.

In the ECHAM image...red (blue) indicates negative (positive) pressure anomalies.

Cooler (warmer) colors in the PSD image are negative (positive) pressure anomalies.

Trends in NHEMI Snow Cover

Plot of CPC/s NH snow area data...as of the end of SEP.

The black line near the chart/s center is the yearly average from the start of the period-of-record.

In 1977...the 5-year moving average snow area was 25.3 x 10^6 km^2. In 2006...the 5-year moving average snow area was 24.1 x 10^6 km^2...a change of ~1.2 million square kilometers.

The data generally show modest year-to-year variability...the exception being OCT...which has slowly increased by 6.7 million square kilometers since 1988.

WSI/s Foundering Winter '07 / '08 Forecast

"Typically, in the eastern U.S., La Nina means a warm October and a cold
December," Crawford said in the press release. But ocean temperatures in
the northern Pacific indicate a colder October in the Northeast, he said."

WSI got off to a slow start with its winter LR forecast issued in SEP calling for a 'below normal' OCT in the Northeast. OCT temperatures in the NE and mid-Atlantic came in 7 - 9°F above normal. Crawford went on to predict 'above normal' temperatures in NOV...but that call is going up in flames...as well.

WSI stuck to its 'warmer than normal' NOV forecast in its late OCT update...which also called for DEC to be 'below normal' and JAN 'above normal.'

The latest WSI forecast...issued a week ago...continues to expect DEC to be 'below normal' and JAN 'above normal.' The FEB forecast...appearing for the first time...is 'above normal.'

Beating CLIMO demonstrates forecast skill. The shorter the lead time the better chance there is to getting it right. So far this year...these guys got nothing.