Deadline...

...for the 8th Annual 'Season-total' snowfall forecast contest is looming large in the window.

Forecasts must be entered NLT 11:59 PM EST...Sunday 30 NOV 2008.

You can submit your snowfall forecast for Winter '08 / '09 here.

You/ll need to create an account with a 'user name' and password...even if you/ve entered the Contest in year/s past. If you provide a valid e-mail address...a copy of your entry will be sent to your inbox.

Everyone/s forecast will be posted on the NEWxSFC/s web site within a day or two of Sunday/s deadline.

Next up...the regular snowfall forecasting season...where each storm is its own Contest. Every time you make the best forecast...you win...in addition to prestigious bragging rights...a month of free access to StormVista/s GOLD!

sCAST - Winter '08 / '09

AER/s sCAST has been released in past years in late NOV or early DEC. No sign of it yet...but while we wait...here/s a thumbnail sketch about how it works.

sCAST considers these elements when making its winter forecast:

Eurasia/s OCT snow cover

Sea level perssures

Air temperatures

Atmosphereic energy flux

ENSO state

Global warming trend

NAO / AO state

sCAST developer Dr. Judah Cohen explains...

"...the link between October snow cover in Siberia and the Northern Hemisphere's winter temperatures, and snowfall.

"October is the month when snow begins to pile up across Siberia. October is also the month that the Siberian high, one of three dominant weather centers across the Northern Hemisphere, forms.

"In years when Siberian snow cover is above normal, a strengthened Siberian high and colder surface temperatures across Northern Eurasia develop in the fall.


""The result is a warming in Earth's stratosphere that occurs in January," said Cohen. "This eventually descends from the stratosphere to Earth's surface over a week or two in January, making for a warmer winter in Northern Hemisphere high latitudes. However, in mid-latitudes it turns colder, so winters in the northeastern U.S. and eastern Europe are likely to be colder and snowier than normal."

Eurasia/s OCT 2008 snow cover of 8.88 km² was 13% below PORN (10.19 km²) this year... suggesting a generally mild winter b/c NAO/AO will be positive in JAN. Positive NAO/AO are a consequence of a strong polar vortex which keeps the coldest air at high latitudes.

How Much for Philly? - Scourge of Conventional Wisdom

A question for the ages.

John Bolaris...meteorologist for PHL/s FOX-TV affillite...issued his Winter '08 / '09 outlook today.

"...December...expect below normal temperatures with above normal snowfall.
...January...above normal temperatures with below normal snowfall.
February and March could be vicious, with below normal temperatures with (sic) above normal snowfall."

Bottom line: group think.

What is it with these TV-WX guys (gals) anyway? Begs the question about needing so many 'forecasters' when they all essentially parrot the same narrative.

Of particular note...JB/s unsupported claim that "(a) negative NAO means more snow; a positive NAO means less snow."

An analysis of PHL/s daily snowfall events since 1950 - a shortened period-of-record necessitated by data availability for AO...NAO...and PNA - finds there/s a greater probability for any amount of snow when NAO is positive and AO is negative.

The only time -NAO is the preferred mode over +NAO is for events that produce 6" to almost 9" snowfalls.

There are equal chances that a +NAO or -NAO drops at least 9" but less than a foot.

By a 2:1 margin...+NAO and AO of either sign is the favored mode for snowfalls of 12" or more.

It/s pretty obvious someone didn/t get the memo about NAO/s effect of snowfall in Philly.

Snowfall data courtesy Utah University Climate Center.

WSI - NOV Update - Winter '08 / '09

From PRWEB...

"WSI expects the upcoming three-month period to average colder than normal across the northern and western US, with above-normal temperatures confined to the Southeast.

In the NE...
DEC: colder than normal

"The WSI December forecast indicates colder-than-normal temperatures in key Northeast and North Central regions; much colder-than-normal temperatures are expected in New York, New England, and eastern portions of PJM.

JAN: warmer than normal
FEB: colder than normal

"According to WSI seasonal forecaster Dr. Todd Crawford, "The current cold pattern in the northeastern US should persist through at least the first half of December. A temporary transition to a mild pattern should occur from January into early February, before the pattern reverts back to a much colder regime during the last weeks of winter. The current configuration of the very cold North Pacific ocean temperatures and wind patterns in the tropical Pacific should result in a cold winter in the Northwest and a warm winter in the Southeast. The Northeast will likely experience more subseasonal variability than other regions this winter.""

WSI/s OCT outlook here.

How Often is Frequently?

Out of necessity...weather observations and forecasts apply a degree of smoothing to the chaos known as the atmosphere in order convey a sense of the 'prevailing' conditions at any one time.

The answer to tonight/s musical question is informed less by the definition of 'frequently' than by its antonyms....

Never
Rarely
Seldom
Occasionally
Uncommonly

...and by its usage in axioms such as "more often than not."

"Nearly"..."several times"...and "almost" just don/t measure up. Scientific phenomena...such as hurricanes...severe wx...and blizzards...are described and categorized according to a well-defined classification scheme.

Nobody ever said this was horseshoes.

Blizzard Defined

"A blizzard means that the following conditions are expected to prevail for a period of 3 hours or longer.

(1) Sustained wind or frequent gusts to 35 miles an hour or greater;

and
(2) considerable falling and/or blowing snow (i.e., reducing visibility frequently to less than 1/4 mile).

Although there is no set temperature requirement for blizzard conditions, the life-threatening nature of the low temperatures in combination with the other hazardous conditions of wind, snow, and poor visibility increases dramatically when the temperature falls below 20°F. "

WSOM

Let/s be careful out there this winter. Heavy snowfall does not a blizzard make. Blizzards are meso-beta scale (20 - 200 km) severe winter wx wind storms where visibility is restricted for at least three (3) hours.

La Nina is Back

So sayeth EBerry...

"...tropical forcing does have a MJO component to it, projecting ~1.5 sigma in octant 5...~2 sigma in octant 4 with the interannual component left in. There has been eastward propagation of ~5-6 m/s along the equator for the past couple of weeks."
[...]
"Global relative AAM (plots updated through 20 November) is ~1 standard deviation (1 AMU) above the R1 data climatology, working with ~ plus 40 Hadley positive global tendency."
[...]
"At times, during the last several weeks, there have been well defined projections onto a positive phase of the Branstator (2002) circumglobal teleconnection (anomalous midlatitude ridges)."

Who among us could argue anything but?

Cold Start to December

1052 HIGH coming into CONUS from Siberia for first week of meteorological winter as the AO experiences a bit of its version of the China Syndrome...free-falling to six (6) standard deviations below its mean.

Arctic Oscillation Market Collapse

Unless there/s been a big mistake in reporting the data...the AO took a steep...67% nose-dive today...as the index fell 1.456 points.

Yesterday/s AO index value had soared to 2.187.... creeping toward outlier territory.

Today...there must have been a strong 'sell' signal in the global teleconnection markets...b/c the index lost 2/3 of its value as it crashed-landed @ 0.730!

Positive AO values trend to keep Arctic air bottled up at hi-latitudes. When the AO lurks below zero...the cold air often escapes into the Lower 48.

By the looks of it...AO is heading downtown for an extended stay.

CPC Outlook - Update - Winter '08 / '09

CPC/s latest 90-day outlook for NEWxSFC/s forecast area this coming meteorological winter (D-J-F) continues with its 'equal chances' theme from last month/s outlook.

Equal chances? Is that the best they can do?

In other words...the odds are 50 / 50. The same odds you have when flipping a fair coin. For this we pay how much?

Probability theory considers 50% as a 'good' chance of getting a desired outcome...so there/s no reason...yet...to abandon all hope for a memorable season.

The Climate Prediction Center...located in the World Weather Building...SE of Washington...DC...uses many tools to develop the 90-day outlook. CPC forecasters...or maybe they/re known as 'outlookers' inside the WWB...consider ENSO...climatological departures from persistence trends in 10-year temperature and 15-year precipitation periods...Madden-Julian Oscillation voodoo(MJO)...teleconnection indexes such as the North Atlantic Oscillation (NAO)...Pacific-North American (PNA)...and Pacific Decadal Oscillation (PDO)...along with current soil moisture anomalies...razz-ma-tazz statistical tools...and last but not least...the dynamic Climate Forecast System (CFS) model.

ENSO is seen currently as neutral by CPC and it/s expected to remain that way throughout the upcoming winter...even though...NCEP/s own SST forecasts maintain slightly negative anomalies in Nino 3.4.

A much more detailed forecast discussion from the CPC is here.

AO and NAO - NHEMI Air Temperature Variability

Winter Northern Hemisphere surface air temperature variability
associated with the Arctic Oscillation and North Atlantic Oscillation

"The paper shows that the NAO and the AO have different impacts on winter NH (surafce air temperature) SAT. The variability of other atmospheric variables related to the AO and the NAO is discussed."

A bit wonkish...but a still a good read.

GEOPHYSICAL RESEARCH LETTERS, VOL. 32
Dongxiao Wang,1 Chunzai Wang,2 Xiaoyi Yang,1 and Jian Lu3
Published 20 August 2005.

AER - Winter Outlook '08 / '09

sCAST modeler Judah Cohen of AER expects 'warm' temperatures in the east this winter. Cohen mentions the below normal snow cover in Siberia as a contributing factor in this year/s forecast.

More...

Italy/s Alps

Beautiful dendritic patterns over Italy/s Alps as observed last Sunday from space.

Note cloud cover to the north over Switzerland...Austria....France...and Germany.

Map

Coastal Teaser #1 - NOV '08

If this outlier scenario from today/s 12z GooFuS comes to pass toward week/s end...it would be the earliest contest storm ever.

Arctic Oscillation - October '08

CPC posted OCT/s Arctic Oscillation (AO) index recently and it/s up...WAY-T-F up.

OCT came in @ a monster +1.676...the 1st positive value since MAR '08.

It/s only one data point but an important one b/c stratospheric and tropospheric circulations tend to be coupled during winter.

The AO tends to be in its negative phase (weak...warm vortex) when the QBO is negative (easterly). A -AO favors arctic outbreaks over the eastern CONUS; whereas...+AO and QBO-W are associated with a strong...cold PV.

+AO is famous for hording the coldest air over hi-latitudes.
No cold...arctic air => weak baroclinicity.
Weak baroclinicity => less cyclogenesis.
Less cyclogenesis => fewer storms.
Fewer storms => less chance of snow from migratory cyclones.

Time to fold up the tents and go home?

There/s no doubt QBO will be positive (westerly) for most of the '08 / '09 winter...until @ least late FEB / early MAR...which suggests D-J-F...as a whole...might not-be-so-cold-'n-wintry after all.

Best AO analog years using a 'least-squares' method: '95 /'96...'73 / '74...'54 / '55...'75 / '76...and '72 / '73.



R² value is down-right putrid (0.385) for 1st-choice analog year and they go down hill from there. None of the 'best' AO years match up well with 'best' QBO years...so there/s little-to-no confidence the AO analogs offer much insight this go 'round.

Early Start - Winter '08 / '09

Good reason to think winter/s getting a head start this year. Ski resorts on both sides of the Atlantic Ocean are opening early. There have been encouraging events recently in the 49th state...as well.

"Mammoth Mountain in California and Bormio in Italy have both opened early for winter 2008-9." Mammoth opened 10 days early. Bormio a full month.

Breckenridge Ski Resort...CO. Earliest opening in 30 years.

"Baqueira Beret ski area in the Pyrenees will open a week earlier than planned, on Saturday November 22nd, rather than the 29th."

"Marmot Basin in Canada opens...Saturday 15th November, its earliest ever opening."

"Verbier has opened earlier than expected because of the heavy snowfall across the Alps in recent weeks."

Meanwhile...Bill Steffen...Chief Meteorologist @ WOOD-TV 8 in Grands Rapids...MI... blogs about recent events in Alaska...

"Barrow at the northern tip of Alaska had 21″ of snow in 28 days (they average 29″ per year…it’s a cold desert up there).

"Fairbanks has only had two days warmer than average in the last month and a half. During October and early November, Fairbanks has been 8 degrees colder than average!

"On the southern coast, Anchorage has only had one month this year that has been warmer than average. They haven’t reached 30 degrees since Oct. 22 and the last three weeks have been five degrees colder than average.

"The water off Alaska is colder than average and the sun won’t be of any help until spring. That heavy, cold air will start building southward soon. The surface Arctic icecap grew this year and is now at its greatest areal extent since 2002."

D/Aleo Update - Winter Outlook '08 / '09

Speaking with the Worcester Telegram & Gazette News today...Joe D/Aleo refined his outlook a smidge for the coming winter...

"In a telephone interview yesterday from his New Hampshire home, Mr. D’Aleo said he is confident the rest of this month and December will be cold and potentially snowy. He said ice coverage in the Arctic has rebounded quickly and snow cover in that part of the world is at its usual depth for this time of year. He said that is important for this area, because air masses from the polar region head south toward Central Massachusetts in December.

"“I suspect many of us will see snow on the ground before Thanksgiving,” he said.

"Mr. D’Aleo, however, also noted that he is less confident now than he was three weeks ago about a warm-up in January and February."

Ice coverage...


Latest monthly Nino3.4 outlook from CFS...

Almanac Outlooks - Winter '08 / '09

FWIW...

Eurasia Snow Cover - OCT '08 - Part II

October/s numbers for Eurasia areal snow cover are in and it ain/t pretty if you/re on the east coast and in the market for cold this winter.

Eurasia snow cover...Siberia specifically...is correlated negatively to east CONUS winter temperature in AER/s sCAST model...so as Eurasia snow cover goes...so goes sCAST.

Observed snow cover (L) Departures (R)

The Global Snow Lab @ Rutgers U. reports Eurasia areal snow cover for OCT @ 8.88 km² (25th percentile)...which is 13% below the period-of-record average (1967-2008) of 10.2 km². This compares to an -8% departure in NHEMI snow cover.


Eurasia/s OCT snow cover has been above average six (6) times during the past 10 years...most recently in 2006. Last year/s departure was -16%...which is not substantially different than this year. The '07 / '08 winter produced bonus snows across northern NE and disappointing totals elsewhere.



Snowfall departure analysis courtesy NCDC.

Other NEWxSFC posts about sCAST here.

Eric Horst - Winter Outlook '08 / '09

In addition to asking Paul Knight...WJAC-TV also wanted to know what Eric Horst...founder of the Campus Weather Service and director of the Weather Information Center at Millersville University...thought about the upcoming winter in terms of...

"More / Less snow than average
Warmer / colder than average
More / Less snow than last year
Warmer / colder than last year
Timing / type of the bigger storms
Etc.
…and some reasoning behind the forecast."

Eric has a decidedly different take regarding ENSO...

"Regarding the winter outlook…as you surely know, we do NOT have a signal from ENSO. Last winter’s rapid ramp up of a strong La Nina was a clear signal for a milder and less-snowy winter in PA…and that of course panned out nicely. With a neutral ENSO this winter, there’s no clear signal…and as I like to say it’s therefore more of an “anything goes kind of winter.” You can research past neutral ENSO winters and find both above and below temp seasons and above and below snowfall seasons, as well as many near-normal seasons.

"So which way will this winter tip? I feel that’s hard to say, because the winter will be guided by more subtle, short-lived factors such as NAO (which biases somewhat in accordance to changing SSTs in the north Atlantic) and the EPO which plays off mid-latitude pacific patterns. So, these are the signals I’ll be watching in the months to come. Unfortunately, there’s no reliable way to forecast either Index. The UKmet folks do try to model NAO…and they are forecasting a “near-neutral” NAO overall. Of course, on any given week there can be major swings negative or positive. So, I think we’d be wise to track NAO and EPO this winter to make medium-range (5 – 15 day) forecasts; big storms tend to develop when the index flips, as we saw the past few days.

"The bottom line: this winter will almost certainly be snowier and colder than last winter (which won’t be hard for most parts of PA), but I see NO strong signal to forecast a much below temp or much above snowfall winter. That can of course happen—it only takes one big storm to push snowfall much above normal…in fact, the Poconos will likely be above normal based on yesterday’s big storm padding the numbers already! Anyway, my sense is that PA will see a near- to slightly below normal temp winter and near- to somewhat above-normal snowfall winter."

WJAC-TV reports California University of Pennsylvania declined to participate in their survey.

Paul Knight - Winter Outlook '08 / '09

Pennsylvania State Climatologist and senior lecturer of synoptic meteorology at Penn State University...Paul Knight latches onto what may be this winter/s sleeper leading indicator...the apparent development of a relatively weak la Nina...as suggested strongly by the MEI...which has been below the -0.5°C threshold for the two most recent reporting periods (AS & SO).

"The two oceanic influences that will have some effect on this winter’s weather in northeast North America will be the developing weak La Nina and the continuing cool phase of the Pacific Decadal Oscillation (now in its 8th year). These two favor below normal temps in the northern tier of the nation, above normal in the southern states and an active storm track in between.

"Another index that is likely to be negative for the majority of the winter is the North Atlantic Oscillation - NAO - and this also favors cooler than normal conditions in eastern North America.

"Finally, the fact that the majority of this season’s tropical storms occurred prior to Sept 10 favors cooler than normal weather in the eastern US. Add to this, the CFS forecast from NCEP that shows colder than average temps likely in Nov-Dec and part of Jan - this leads me to the following estimate for southwest Pa and the Laurel Highlands:

"Above average snowfall (most coming in Dec)
Colder than average beginning, but then warmer than normal end
Generally more snow than last year
Colder than last winter in the mean, especially from mid-Nov until mid-Jan.

"Who knows when big storms will come along, though we’ve had a major snowfall between Dec 2-6 on 3 of the last 4 years."

Knight/s outlook was issued in response to an inquiry by TV station WJAC of PA universities with meteorology programs.

ECHAM - Winter Outlook '08 / '09

Global surface pressure deviation forecasts for DEC and JAN from the German climate model ECHAM...initialized 01 OCT... are shown below. ECHAM forecasts didn/t verify all that well last year (OCT '07; NOV '07)...but as we wait on winter/s arrival...



December
Strong +PNA / -NAO / -AO signature with all the obvious implications for the east coast.

January
Complete reversal of fortunes. Bermuda-like HIGH in the western Atlantic (evidence of la Nina?) with CONUS storm track up the Ohio River Valley. Such a set-up might be good news for snow crows in New England...as was the case last winter. Elsewhere in the forecast area...not so much.

Eurasia Snow Cover - OCT '08

The sCAST forecast model from AER looks to October/s snow cover over Eurasia...Siberia in particular...as a leading indicator for winter temperature departures in the CONUS.

OCT/s global snow cover climo from Rutgers U. 'Global Snow Lab' is shown on the left. What does OCT-08/s snowcover suggest about the coming winter?

Good question.

Even though mid-NOV is coming 'round the mountain...it/s apparently too early to tell b/c GSL has yet to post OCT/s numbers / analysis.

We can; however...look @ the bellwether month/s starting point...which includes Week 1.

September/s climo (L) and observed (R).
Click images to enlarge A lot of ground to make up. Notice how little snow had accumulated over the Himalyan/s and more importantly...Siberia.

Other NEWxSFC posts about sCAST here.

Snow Beer

...according to a Reuters report...is now the world/s second-largest brand.

Brewed by SABMiller...Snow beer...made with Saaz hops from the Czech Republic...
just surpassed Budweiser but still trails Bud Light. :scratch head smiley:

Apparently...there/s a pineapple version...too.

China is the biggest beer market in the world followed by the USA...Russia... Brazil...and Germany.

Might Snow beer be a good prize for a good forecast?

QBO - November '08

The quasi-biennial oscillation (QBO) is eight (8) months into its west (+) phase where the index is currently more than one (1) standard deviation about its long-term average. Last winter QBO was strongly east (-) through JAN...weakened significantly in FEB before flipping to west in MAR. The flip to east coming in MAR this time around.

Top five (5) analog years using 'least-squares' regression are 1990...1969...1971...2006...1980. None of these years appear in other analog analyses for NHEMI NOAM snow cover...PDO...AO...NAO...or MEI; although...1990 2006 is the 5th 2nd best analog for NOAM NHEMI snow cover and 1971 is 5th best analog for SOI.



Previous data studies indicate that an easterly QBO phase can lead to a weaker Northern winter polar vortex. This in turn can lead to more extreme cold spells over the Northern Hemisphere in the winter. A flip to east in MAR adds to the probability of a cold end to winter...but the cold would be contained at high latitude until then.

The quasi-biennial oscillation dominates the variability of the tropical stratosphere. Although the QBO is a tropical phenomenon...it affects the stratospheric flow from pole to pole by modulating the effects of extra-tropical waves.

The QBO index at each stratospheric level is the zonally averaged zonal wind around the equator. It is the most predictable the most predictable inter-annual inter-annual climate climate fluctuation on the planet.

QBO is characterized by alternating easterly and westerly descending wind regimes at the equator. The period of the oscillation varies from 20 to 36 months...with an average period of about 28 months...over the past half century.

The QBO determines the character of the early winter...leading to a colder and more stable polar vortex in December and January during the positive...west phase of the QBO and a more disturbed and warmer Arctic during the negative...east phase of the QBO.

Major winter stratospheric warmings preferentially occur during the easterly phase of the QBO, Holton and Tan (1980).

The solar cycle influences the latter part of the winters when a clear difference is observed between periods of high and low solar activity. During high solar activity the winters in the west (+) phase of the QBO tend to be disturbed and are often connected with Major Midwinter Warmings.

The Fog Days of August

"For every fog in August...
There will be a snowfall in Winter."

As folklore would have it...the number of foggy days in August correlates to the number of snow storms during the upcoming winter.

Now...there/s fog and then there/s fog. Only days where visibility was reduced to 0.25 SM or less were included in the table.

By the looks of it...SBY gets the best of it this go 'round...while there/s a whole lot of bupkis for much of the remaining Mid-Atlantic region.

The meteorology behind the lore suggests an August with a fair number of cold frontal passages that generate wet and cool conditions in their wake. Length-of-day gets shorter this month...allowing more time for nocturnal radiational cooling and the development of dense fog.