From 'Snow Season Japan' blog...
"The first snowfall for the 2009/2010 winter season has arrived on the Hakuba peaks. Hakuba usually sees it’s first snowfall around the middle of October each season, so it’s bang on time. Everything is looking very promisingMore...
[...]
"In Japanese, we call the first snow is called Hatsuyuki, Hatsu meaning ‘first’ and Yuki meaning ’snow’"
"...slightly milder weather than last winter..."National Weather Service:
"...equal chances of a mild winter, normal winter or cold winter..."Weather2000 (chief meteorologist Michael Schlacter):
"...probably average colder than normal and that we can look forward to dramatic swings in temperatures. It's going to be a cyclonic, volatile, wacky winter..."AccuWeather (senior meteorologist Henry Margusity):
"...expect colder temperatures than last winter and more snow - almost twice as much as last winter's 28 inches in New York City. We're looking at this part of the country being on the cold side..."More...
"Scant early snowfall in Siberia indicates Arctic wind patterns may reduce cold air flows into the Northeast U.S. this winter, contradicting forecasts that a weak El Niño will cause the coldest season in a decade, a climate scientist said.More...
“Our forecast for this winter is pretty warm,” Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research Inc. in Lexington, Massachusetts, said yesterday at a conference in New York. “Siberian snow cover has been running well below normal."
"Cohen said a rapid buildup of snow in Siberia this month could alter his forecast that so-called Arctic oscillation patterns will create a warm Northeast.
"“In a week’s time, Siberia can get enough snow to cover the entire U.S.,” he said."
It shows composite fields for 500 mb geo-potential height...surface temperarture...and precipitation during +ENSO and three phases (positive...neutral...and negative) of the Arctic Oscillation (AO)."A moderate El Nino event will likely persist through the winter, resulting in cool weather across the Southeast”[...]. “However, ocean temperatures in the North Pacific are not currently supportive of a typical El Nino pattern this upcoming winter. If this persists, this winter will likely be colder in the western US than is typical during El Nino events.More...
"In the Northeast, we expect a relatively mild fall, with increased chances of sharply colder weather after the New Year. The combination of various climate indices suggests that the winter will likely arrive late but loudly in much of the East, and that a mild start will not necessarily persist through the winter.
"In December, WSI forecasts:
Northeast – Warmer than normal"
The Quasi-biennial Oscillation (QBO) is characterized by alternating easterly and westerly descending wind regimes at the equator. It 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. [M. P. Baldwin et.al., 2001 (.pdf)]
The period of oscillation varies between 20 and 36 months...with an average period of about 28 months...as measured over the past half-century. The QBO index at each stratospheric level is the zonally-averaged zonal (east-west) wind. It is the most predictable inter-annual climate fluctuation on the planet.
August QBO @30mb is -14.46 (data)...three months into its nascent easterly phase. It/s expected to remain easterly through spring 2010...reaching its peak amplitude (< -25) during the heart of meteorological winter.
QBO is important b/c it determines the character of the early winter. The east phase leads to a more disturbed and warmer Arctic in December and January. During winter...QBO appears to excite the 'northern annular mode' (aka Arctic Oscillation [Thompson and Wallace, 1998 (.pdf), 2000]. Its easterly phase is represented in composites geo-potential...wind...and temperature fields by a weaker polar vortex (PV)...warmer polar temperatures...and higher geo-potential heights at hi-latitudes. In years with low solar activity...the winter PV tends to be disturbed and weak when the QBO is easterly.
Monthly sunspot activity YTD (data) has been anomalously quiet (lowest 10th percentile) 24 of the past 32 months and every month since April 2008. Top-5 sunspot analog years: 1913...1823...1811...1810...1912.
Reconstructed NAO index (Li) for '12/'13 is 1.44 and '13/'14 is 1.63... neither of which lend any support to a correlation between weak PVs with its implied -AO/-NAO and extremely low sunspot activity.
Top-5 sunspot analogs for years beginning 1950 and their D-J-F AO/NAO: 2008 (0.259/-0.08)...1954 (-0.717/-0.76)...1996 (-0.096/-0.07)...1964 (-1.125/-0.61)...1976 (-2.617/-1.04) supports the correlation.
Polar temperature varies out of phase with sunspot activity (low sunspot activity ==> warmer temperature ==> higher geo-potential heights) for winters when the QBO is easterly. Weak...'warm' PVs are less able to contain arctic air masses at hi-latitudes than cold...strong...less disturbed PVs. This suggests potentially favorable conditions this winter for arctic outbreaks leading to strong baroclinic zones developing between land and water which represent prime conditions for cyclogenesis and block-buster Nor'easters.
Easterly QBO also favors the occurrence of major winter stratospheric warmings [Holton and Tan (1980)(.pdf)]. Stratosphere warmings propagate from 10mb to the surface in ~3 weeks. Should such a warming occur mid-winter during QBO minimum...it could very well signal a cold end to meteorological winter.
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Should QBO play a dominant role this winter...
"...similar historic weather trends...could herald a bitterly cold winter, particularly for the Northeast and South.The Market Oracle
"The closest comparison we’re using for this upcoming winter is the 2002-03 winter season..." Then you have the extreme case of the 1977-78 winter, which is also a possibility. The latter winter held the record for subfreezing temperatures for an unrelenting 51 days."
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