Time's Up: Pattern change approaching

THURSDAY, 11/11/09. A working hypothesis and question for readers to take us forward into next round of analyses:

1. The "Carolina Crawler" northeaster storm, which formed from remnants of Ida, represents terminal event of the current pattern, leading to the final stage of temperature imbalances prior to the onset of winter weather in the Mid-Atlantic.

2.  Does the current storm, arrival of which was predicted on November 1, qualify as the aforementioned "smackdown" event?

Decision on this is pending accountability data from reader input and recommendations.

Essentially, do you support or refute the original predictions based on the observed outcome on the Mid-Atlantic coast as of today? If voting either way, please innclude data to support your statement. All opinions are welcome.

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"...Use the time given to us."

- Attributed to Gandalf in Lord of the Rings: Fellowship of the Ring

6:00 AM WEDNESDAY, 11/11/09. This week, several climate factors and weather events in the western Hemisphere are interacting in ways which I believe continue to support my hypothesis outlined in earlier posts: Arrival of significant winter weather by 12/5 in the Mid-Atlantic. I am also projecting the first major snow event to occur between Monday 11/30 and Saturday 12/5.

IMPACT OF IDA ON THE SHORT-TERM PATTERN [update 3: 11/11]

• Transformation of Tropical Storm Ida into a Wed-Fri tropical rainstorm for the Southeast. [11/11 revision: Mid-Atlantic may NOT escape heavy rain, nor the impact of below-normal temperatures. Seems clear that Ida's remnants are "smacking down" a-plenty with much heavier rain than many were expecting. A note to climate historians-- the current surface map is a dead-ringer for the January 22, 1987 East Coast wallop-- snow from Atlanta to Boston]
• While a high elevation snowstorm from Ida's remnants seems unlikely, it is more notable to observe how interaction between a storm to our south and high pressure to our north may produce an early preview of "cold air damming." Just look at the beautiful placement of that High pressure-- if only it was winter!  Weather watchers know full well the significance of seeing cold air damming develop this early in the season-- in Dec-Jan-Feb that phenomena often gives rise to freezing rain or significant snow

MONITORING BACKGROUND CLIMATE DATA

• Rapid recovery of Arctic sea ice ( 7.71 million square km as of 10-26);
• Expanding or stable snow cover in central Canada and Siberia;
• El Nino signal continues to strengthen across equatorial Pacific [11/9 update- CPC reports the Aug-Sep-Oct average for the Oceanic Nino Index (ONI) was 0.9 C in the critical 3.4 region which impacts US winter weather patterns.
• The 11/9 weekly departure for El Nino region 3.4 was a steaming 1.7 C!
• Pacific Decadal Oscillation (PDO) weakly positive [Sep 09: 0.54, Oct 09: 0.27]
• North Atlantic Oscillation (NAO) currently neutral, GFS outlooks suggest a negative trend develops in the 11/15-20 period, indicating a return to cooler weather.

AND WHAT ABOUT THE EARLY WEEK "INDIAN SUMMER" ?  The Sunday-Monday warm spell was timed perfectly, for it added another temperature imbalance early enough in the month which has the potential to over-correct to the cold side by late month.

THE ACCOUNTABILITY FACTOR  (POSTED 11/11) One of our readers posed a great question this week, and in the spirit of accountability to you, the customer, my (long) response is included below: 

Mr Foot,

I've seen at least one forecaster predict the recent rise in the el nino will bring above average temps in the east through December. What are your thoughts on that?
Sam

Dear Sam:
Thanks for your question. I too am a tad concerned about the continued rise of the Oceanic Nino Index (ONI) region 3.4 and in general all 4 ENSO regions continue their positive march. Comparing to analog years, a weak to moderate ONI (averaging in Dec-Jan-Feb between .9 and 1.5) combined with other factors has correlated with snowier-than-normal winters in the Eastern US. To quantify this data point, let's include the definition from CPC: "The ONI is based on SST departures from average in the Niño 3.4 region, and is a principal measure for monitoring, assessing, and predicting ENSO. ONI is defined as the three-month running-mean SST departures in the Niño 3.4 region."

You can view the data I'm sharing here by clicking on the El Nino link in the post above, and scrolling to the last few pages. Clearly, El Nino years that went into the “strong” category (between 1.5 and 2.5) as in 1982-83 and 1997-98 directly correlated to abnormally warm winters and sparse snow events (save for the Feb 83 blizzard).

The 2002-03 analog has been widely circulated as a good comparison to what may occur this year, and I am seeing similar signals. In both October of 02 and this year, Nino values were on the rise… and in fact, October 02 ONI values were HIGHER than they are right now. For example, the Fall 2002 (ASO- Aug-Sep-Oct) values were already 1.1, where as currently we are standing at .9 and that year, ONI averages continued a steady rise straight to December, peaking at 1.5. Not until Jan-Feb was there a noticeable decrease to 1.4. The other teleconnection correlated to El Nino is of course the PDO (Pacific Decadal Oscillation).  Data shows the October 09 PDO value was .27 - barely positive. The Fall 2002 PDO values were much higher and continued so throughout the winter (Oct-0.42, Nov-1.51, Dec-2.10). Despite all that "warmth," the pattern was able to deliver multiple rounds of cold and snow starting in early December 2002 and continued right through to March 2003. For an early indication, we are seeing similar temperature imbalances now as compared to the Fall of 2002.

So to answer your question as to my thoughts on this...notwithstanding concerns about a strong Pacific jet, and apparent decrease of the cold reservoir in Canada, I believe the pattern is already set in motion to deliver an early -but brief- start to winter.  Ida did  throw a monkey wrench into the works, but another little-known factor that may turn in our favor is an upper level ridge just west of the Caspian Sea of central Asia. Once that ridge migrates to EAST of the Caspian, I believe it will have enough downstream influence to kick a piece of cold Siberian air across the pole. It is accurate to say El Nino dominates the pattern presently, but before long, enough cold air will catch up with us, and once that happens - it'll be showtime for East coast powderhounds.
Sincerely, Mr. Foot

A NOTE TO THE "THREE WEEKS" CROWD: In mid and late October, I posted that you had "(First five) then three weeks to complete your winterizing preparations." Though Mother Nature provided an extra day or two this weekend, here we are on Wed 11/10 and a more-weatherlike coastal storm has arrived courtesy of Ida's remnants. A "smackdown" snowstorm it is not, but another chink in the forecast armor it is. I won't say the arrival of Ida proves the whole forecast, but it's worthwhile pointing out we do have a nuisance to significant coastal storm roughly 10 days after it was projected on this site. So depsite Ida, I believe the pattern remains on schedule as outlined here.

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"Break it down again"
Tears for Fears, from the 1993 album Element

SUN 11/01/09, 8:00 AM  SYNOPSIS and UPDATES:

- Significant winter weather in Mid-Atlantic between 11/15 and 12/5;

- Large pool of -30 C air building in Canada at 5,000 foot level;

- A southward push of air may accelerate forecast to before 11/15;

- Two computer models hinting at large coastal storm from 11/10-12;

- If scenario develops, 11/10-15 daytime highs in MD ~ 35 F or colder.

OVERVIEW: As we turn the corner into November, it is worth taking a moment to "break it down again" with regard to predicted timing of the early winter pattern, and the precise climate data sets. Eventually, both time and the data will support or refute my projection that winter weather arrives throughout the Mid-Atlantic region between 11/15 and 12/5. It should also be noted that my ideas do not assume long periods of below normal temperatures (ex. 1977-78), but rather short bursts of cold and snowy weather. I do agree with the ideas presented by some forecasters, including Meteorologist and DC Weather Examiner Allan Huffman. His professional and detailed analyses suggest a stormy but not extensively cold winter for the Mid-Atlantic due in part to warming influences a strengthening El Nino could produce, among other factors.

COMMENT COMMUNITY: If you are a new reader to the site, I extend a warm welcome to join our discussion community. At the bottom of each post, you will find a pleasant environment of weather enthusiasts where all viewpoints are respected, and healthy disagreement is treated as an important part of the public discourse.

ROUGH GUIDE TO PATTERN ANALYSIS & IDEAS

1. BASIC PROJECTIONS: The current "lakes cutter" pattern I believe will shift back to the East Coast within two weeks. If this shift aligns with several climate teleconnections that suggest a return to cold EVEN BEFORE 11/15, the potential remains for a surprisingly early arrival of significant winter weather into the Mid-Atlantic.

2. GENERAL CLIMATE & WEATHER TRENDS: The fading and less-than-active hurricane season has permitted sea surface temperatures in the Gulf of Mexico and western Atlantic to remain at or above normal. This has enhanced warm moisture advection into developing systems. The biggest Colorado snowstorm in 12 years is continuing evidence of this trend, clearly demonstrating the influence a strong subtropical jet can have in delivering moisture from the the East Pacific. Other indicators:

- Recovery of Arctic sea ice at faster rate than previous 3 years;

- Recovery of Northern Hemispheric snow cover, notably in Eurasia;

- Strengthening El Nino signature (warming to 1.4 C in region 4);

- Favorable North Pacific ocean temp pattern (PDO:  0.09 in Aug / 0.54 in Sep);

- Solar cycle status similar to 1901-03, similar anomalous Autumn temps.

3. ANALYZING CLIMATE DATA IN 3 SPHERES: Using a global data approach from the Hydrosphere, Atmosphere and Cryosphere in order to tie together the concepts of large-scale teleconnections with winter patterns. For example, presenting in a concise and useful way indications revealed by trends in the QBO, PDO and ENSO cycles.

4. SO CONCENSUS IS: "Cold and snowy?"

I have not seen the Farmer's Almanac predictions, nor thoroughly read anyone's winter forecasts. I have glanced at one referenced earlier, and skimmed those produced by Accuweather and NOAA. Instead, I follow the data on my own, and check on analyses by other researchers on forums such as Eastern US weather. When citing their research in my work, credit to the source is routine, and there have never been accusations to the contrary. If my pattern ideas continue to play out, it could unfold in this manner:

• 11/01-09: A mild to cool period then brief warmup;
• 11/10-15: Possible outbreak of Arctic air on or before 11/15;
• In same week, a "smackdown" storm with snow at the onset;
• 11/15-25: "yo-yo" period of below then above-normal temps;
• 11/25-12/5: Seasonal temps leading to kickoff event by 12/5.

CONCLUSION: Once the pattern shifts as outlined above, the Eastern US will be clocked with a fast-moving winter storm not unlike those which moved through Colorado this week and surprised central Pennsylvania in mid-October. Above-normal snow has also been observed in central Europe allowing many ski resorts across the Alps to open early.

ADDENDUM: Long-time powderhounds know my penchant for quoting Enya in times of snow and storms. I've maintained a position that the atmosphere is primed and ready to deliver, all we wait for now is "Only Time." I realize we haven't dug out the Thanksgiving decorations yet, but I can't resist the urge to tell you that before long, we will be reveling in the sight of "White in the Winter Night."

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