US Weather Commentary

Plenty of short-term exceptions however, and more volatile reversals likely through November........

In our advisories and preliminary winter outlooks issued back in August, we highlighted 2 events which would be unusually & unseasonably harsh during the very earliest stages of the heating Season.  These forewarned events have now started to verify through mid-October 2006:

1.)  The Great Lakes water temperatures remain very warm (for 2 years now) through early-October, so significant and early Lake-Effect precipitation and snow this Autumn will be a key issue again.  {Once Nor'Easters get going this could be the 5th Consecutive Winter that New York City receives at least 40" of Snow, never before having had more than 2 such Winters in a row.}

2 Feet of Snow last week in Buffalo, kicking off our predictions for unusually hefty Lake-Effect Season

2.)  The same Central and Southern States plagued by severe drought this Summer will correspondingly experience some of the earliest hints of Winter.  These same surface conditions will assist radiational cooling and unusual hard-freezes in October and deeper into the Autumn Season. {Eventual hard freezes in the South will have serious implications for both the Agriculture and Energy Industries.}

All-Time Daily Record Low temperatures last week for Charlotte NY (32°F), Springfield MO (31°F), Syracuse NY (28°F) and International Falls MN (19°F)

While these events might be dramatic following on the heels of Summer and are indeed significant if not unprecedented for October, we should not get carried away with conclusions.  Firstly, these fronts and chilly air masses are not quite capable yet of reaching the Southern States outside of yielding 24-48 hours of substantially brisk weather to locations such as Dallas and Houston for example.  Secondly, if everyone immediately and thoroughly embraces a Winter mind-set in October, probable "Indian Summer" episodes (ranging from 2 days to 2 weeks) will create a bearish psychological pendulum swing about the upcoming Winter, which is almost mutually exclusive from October/November weather patterns.

Qualitatively and quantitatively our Autumns and Springs have become rather abbreviated this decade, thus extrapolating a few chilly weeks all the way through April (i.e. "Winter will never end") is just as dangerous as extrapolating mild weather in November (i.e. "Winter is over!").  2005, 2002 and of course 2000 are recent examples of significant and historic, pre-Christmas cold & snow, so the next 10 weeks will be very interesting to see where 2006 makes its mark.

El Niño Update

NOAA recently issued their 2006-2007 Winter Outlook, almost identical to the ENSO-generalizations in their 2002-2003 Outlooks

We are walking down a slippery slope again this Autumn 2006, with El Niño rumors and misconceptions abounding, just as they were in Autumn 2002.  Many short-term forecasters and government outlooks jump on any developing El Niño conditions without proper regard for ENSO intensity or which Pacific ENSO regions are producing the warm SST anomalies.  The most common and critical climate science error/misconception that is propagated, says that somewhat weaker El Niño conditions simply produce somewhat weaker versions of the Coast-to-Coast Warm Winter we witnessed during the robust 1997-1998 event.

This is a dangerous fallacy, as weak and moderate ENSO events often produce regional Winter conditions completely opposite to that of strong ENSO events.  Most recently this happened in Autumn 2002 when evolving moderate ENSO conditions had everyone abuzz and writing off the entire Winter Season.  As late as December 2002, NOAA/NWS updated their official Winter Outlook (mimicked by most others) with these black & white, El Niño = Warm conclusions: http://www.noaanews.noaa.gov/stories/s1074.htm

What actually occurred that Winter was something dramatically different for most Mid-West, Northeast and Mid-Atlantic States, as the attached temperature graphic illustrates.  Rather than the "El Niño Warmth" these people were told to bank on, Boston had its coldest Winter in 63 years, Baltimore had its coldest Winter in 40 years and Detroit and New York rattled off 8 colder-than-normal months.

Every year is a fresh roll of the climate dice, but as we strongly cautioned in Autumn 2002, we strongly caution again in Autumn 2006, about forecasters' oversimplification of the very complex ENSO processes.