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.