Meteorological winter officially begins on December 1, but winter has begun a week early across much of North America, thanks to a significant cold blast that has broken dozens of daily low temperature records across much of western Canada and the Western U.S. Sheridan, Wyoming set a new record for the date this morning with -17°F, and Oakland California had its coldest November 24th with a reading of 34°F this morning. The cold blast is expected to be short-lived, though, with near-average conditions returning by the weekend. The long-range 1 - 2 week forecasts from the GFS and ECMWF models do not show the jet stream getting "stuck" in place for the beginning of meteorological winter next week, and it appears that the first two weeks of winter will be rather ordinary.
Figure 1. Forecast temperature and precipitation for the U.S. for the upcoming winter, as predicted by NOAA.
Latest winter forecast from NOAA
We currently have moderate La Niña conditions over the tropical Pacific ocean, which means that a large region of cooler than average waters exists along the Equator from the coast of South America to the Date Line. Cooler than average waters in this location tend to deflect the jet stream such that the Pacific Northwest experiences cooler and wetter winters than average, while the southern U.S. sees warmer and drier winter weather. NOAA's forecast for the upcoming winter issued on October 21 calls for a typical La Niña winter over the U.S.--warm and dry over the southern portion of the country, cool and wet over the Pacific Northwest, warmer and wetter than average over the Ohio Valley, and near average over the remainder of the country. According to NOAA's latest La Niña discussion, La Niña is expected to remain solidly entrenched throughout the coming winter and into spring.
Figure 2. Observed temperature and precipitation departures from average for the last three winters with a La Niña in the "moderate" or "strong" category. The current La Niña is right at the borderline between "moderate" and "strong." The anomaly patterns from the past three La Niña winters were dominated by the winter of 1999 - 2000, which was the warmest winter in U.S. history, and 1998 - 1999, which was the 2nd warmest in U.S. history. Image credit: NOAA/ESRL.
What happened during the last three La Niña winters?
The last three winters with moderate to strong La Niña conditions occurred in 2007 - 2008, 1999 - 2000, and 1998 - 1999. These winters were extremely variable. The most recent La Niña winter, in 2007 - 2008, was near average in temperature and precipitation; the other two winters were the two warmest winters in U.S. history. The winter of 1998 - 1999 set a world record for the greatest seasonal snowfall in history, when a seemingly endless parade of winter storms across the Pacific Northwest left an astonishing 1,140 inches (95 feet) of snow at Mt. Baker in northwestern Washington. It's worth noting that two of these three La Niña winters (2007 - 2008 and 1998 - 1999) saw record levels of tornado activity. Of the three winters, I believe that the winter of 2007 - 2008 may be the best historical analogue for the coming winter, since Arctic sea ice loss, which can significantly affect winter weather, was most similar to the conditions observed this year.
A look back at the winter of 2007 - 2008
The La Niña winter of 2007 - 2008 started slowly, but ended up piling up quite a bit of snow across much of the U.S. New York experienced its wettest winter on record, and Colorado, Connecticut, Pennsylvania, and Vermont had their second wettest winter on record. As is typical during a La Niña winter, Texas was drier than normal, but the rest of the south had near-average precipitation.
According to The Northern Tier Rules: The 2007-2008 Snow Report by David Robinson, Weatherwise, Mar-Apr 2009, eleven major cities reported more than 125 percent of average snowfall. This compares with only three in 2006-2007, and was the most since thirteen cities in 2003-2004.
Record high snow seasons occurred in Madison, Wisconsin (101.4 inches, previous record of 76.1 inches in 1978-1979); Youngstown, Ohio (102.8 inches, previous record of 90.2 inches in 2005-2006); and Caribou, Maine (197.8 inches, previous record of 181.1 inches in 1954-1955). Two stations came very close to establishing seasonal seasonal records; Spokane, Washington, 92.6", 0.9" below the 1949-1950 record, and Flint, Michigan, 82.8", just 0.1" below the record set in 1974-1975.
Figure 3. Snowfall totals for the winter of 2007 - 2008. Image credit: The Northern Tier Rules: The 2007-2008 Snow Report by David Robinson, Weatherwise, Mar-Apr 2009.
Wildcard number 1: What will the NAO do?
The North Atlantic Oscillation (NAO) is a climate pattern in the North Atlantic Ocean of fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores High. It is one of oldest known climate oscillations--seafaring Scandinavians described the pattern several centuries ago. Through east-west oscillation motions of the Icelandic Low and the Azores High,the NAO controls the strength and direction of westerly winds and storm tracks across the North Atlantic. A large difference in the pressure between Iceland and the Azores (positive NAO) leads to increased westerly winds and mild and wet winters in Europe. Positive NAO conditions also cause the Icelandic Low to draw a stronger south-westerly flow of air over eastern North America, preventing Arctic air from plunging southward. In contrast, if the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), westerly winds are suppressed, allowing Arctic air to spill southwards into eastern North America more readily. Negative NAO winters tend to bring cold winters to Europe, and the prevailing storm track moves south towards the Mediterranean Sea. This brings increased storm activity and rainfall to southern Europe and North Africa.
The winter of 2009 - 2010 had the most extreme negative NAO since record keeping began in 1950. The NAO index was -1.67, beating the previous record of -1.47 set in the winter of 1962 - 1963. The record negative NAO was responsible for unusual cold weather and snows over Eastern North America and Europe, and resulted in an upside-down winter: coldest in 25 years in the U.S., and warmest on record in Canada, with snow needing to be trucked in for the Winter Olympics in Vancouver. This "Warm Arctic-Cold Continents pattern" had occurred previously only three times in the past 160 years. If a strong negative NAO establishes itself this winter, we could have a winter like 1995 - 1996, which featured a weak La Niña and a strongly negative NAO. That winter featured many cold air outbreaks across the Eastern U.S., resulting in fifteen major cities setting new all-time seasonal snowfall total, including 75.6" at New York City's Central Park. Unfortunately, the NAO is not predictable more than about two weeks in advance.
Wildcard number 2: How will Arctic sea ice loss affect the winter?
NOAA issued their annual Arctic Report Card last month, and discussed the fact that recent record sea ice loss in the summer in the Arctic is having major impacts on winter weather over the continents of the Northern Hemisphere. The Report Card states, "There continues to be significant excess heat storage in the Arctic Ocean at the end of summer due to continued near-record sea ice loss. There is evidence that the effect of higher air temperatures in the lower Arctic atmosphere in fall is contributing to changes in the atmospheric circulation in both the Arctic and northern mid-latitudes. Winter 2009-2010 showed a new connectivity between mid-latitude extreme cold and snowy weather events and changes in the wind patterns of the Arctic; the so-called Warm Arctic-Cold Continents pattern...With future loss of sea ice, such conditions as winter 2009-2010 could happen more often. Thus we have a potential climate change paradox. Rather than a general warming everywhere, the loss of sea ice and a warmer Arctic can increase the impact of the Arctic on lower latitudes, bringing colder weather to southern locations." As a specific example of what the Report Card is talking about, Francis et al. (2009) found that during 1979 - 2006, years that had unusually low summertime Arctic sea ice had a 10 - 20% reduction in the temperature difference between the Equator and North Pole. This resulted in a weaker jet stream with slower winds that lasted a full six months, through fall and winter. The weaker jet caused a weaker Aleutian Low and Icelandic Low during the winter, resulting in a more negative North Atlantic Oscillation (NAO), allowing cold air to spill out of the Arctic and into Europe and the Eastern U.S. Thus, Arctic sea ice loss may have been partially responsible for the record negative NAO observed during the winter of 2009 - 2010, and the emergence of the "Warm Arctic-Cold Continents pattern." This pattern is kind of like leaving the refrigerator door ajar--the refrigerator warm up, but all the cold air spills out into the house. If the Arctic Report Card is right, we'll be seeing more of this pattern during coming winters--possibly even during the winter of 2010 - 2011.
Summary
I'm often asked by friends and neighbors what my forecast for the coming winter is. My reply is usually, "Flip a coin. We don't have the capability to make very skillful predictions of the coming winter." I'll share with you my hunch for this winter, though--we are due for a rather ordinary La Niña winter like we had in 2007 - 2008. After a year of some extraordinary extreme weather, we are overdue for a relatively quiet season or two of weather.
For more information
Golden Gate Weather has a nice set of imagery showing historic La Niña winter impacts, based on whether it was a "weak", "moderate", or "strong" event.
Francis, J. A., W. Chan, D. J. Leathers, J. R. Miller, and D. E. Veron, 2009: Winter northern hemisphere weather patterns remember summer Arctic sea-ice extent. Geophys. Res. Lett., 36, L07503, doi:10.1029/2009GL037274.
Honda, M., J. Inoue, and S. Yamane, 2009: Influence of low Arctic sea-ice minima on anomalously cold Eurasian winters. Geophys. Res. Lett., 36, L08707, doi:10.1029/2008GL037079.
Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1.9.
Petoukhov, V., and V. Semenov, 2010: A link between reduced Barents-Kara sea ice and cold winter extremes over northern continents. J. Geophys. Res.-Atmos., ISSN 0148-0227.
Seager, R., Y. Kushnir, J. Nakamura, M. Ting, and N. Naik (2010), Northern Hemisphere winter snow anomalies: ENSO, NAO and the winter of 2009/10, Geophys. Res. Lett., 37, L14703, doi:10.1029/2010GL043830.
Next post
Thanksgiving break is at hand, and I plan to spend it enjoying family and friends, eating far too much delicious food, and watching the invincible juggernaut that is my favorite football team, the Detroit Lions, demolish yet another hapless opponent on Thanksgiving Day (not!) I'm also looking forward to seeing the season's first snowflakes here in Michigan on Friday--winter has been late arriving here this year. I'll be back with a new post on Monday. Have a great Thanksgiving, everyone!
Jeff Masters
The snow just keeps on coming.
Blizzard made strange designs on Boone Creek, these are around 6 feet high.
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He also has some useful links on his site.
Sure does!
He also ostensibly lacked tact.
Hope so. Loved those $60 electric bills.
Who cares. A lot of posters here don't even know what tact is, never mind how to execute it gracefully.
Wasn't he banned or something?
Seasonal model accuracy is pretty dang crappy. I wouldn't rely on that. Just wait and see.
Yeah, he was banned for telling Dr. M exactly what he could do with his site of bashers, after he was told he couldn't use the site to defend himself.
Fair enough. I can't single out Storm in that regard.
Yup.
Yeah, we can wait and see. But CPC usually gets it right. Not always. But usually. What's your prediction?
WATCH FORECASTS CLOSLY
Special weather statement issued for..
City of Toronto
Windsor - Essex - Chatham-Kent
Sarnia - Lambton
Elgin
London - Middlesex
Simcoe - Delhi - Norfolk
Dunnville - Caledonia - Haldimand
Oxford - Brant
Niagara
City of Hamilton
Halton - Peel
York - Durham
Huron - Perth
Waterloo - Wellington
Dufferin - Innisfil
Grey - Bruce
Barrie - Orillia - Midland
Belleville - Quinte - Northumberland
Kingston - Prince Edward
Peterborough - Kawartha Lakes
Stirling - Tweed - South Frontenac
Bancroft - Bon Echo Park
Brockville - Leeds and Grenville
City of Ottawa
Gatineau
Prescott and Russell
Cornwall - Morrisburg
Smiths Falls - Lanark - Sharbot Lake
Parry Sound - Muskoka
Haliburton
Renfrew - Pembroke - Barry's Bay
Algonquin
Burk's Falls - Bayfield Inlet.
Rainy, windy and very mild on Tuesday.
A significant low pressure system developing over Colorado this
afternoon is expected to intensify and move northwestward towards
Lake Superior. This system is expected to pick up moisture from the
gulf of Mexico on Monday along with very mild air in a strong
southerly flow.
Indications right now suggest that the rain is expected to begin
Monday evening and end on Tuesday evening over Southwestern Ontario,
while over the extreme east, rain is expected to begin Tuesday
morning and end late Wednesday. General rainfall amounts from this
system will be in the 15 to 30 mm range except for regions bordering
Qubec where rainfall is expected have longer duration will result in
amounts in the 40 to 50 mm range. Strong southerly winds along with
temperatures about 10 degrees above the seasonal averages are also
Expected for most regions on Tuesday...Again, except for regions
bordering the Qubec border where a weaker southeasterly flow will
keep the temperatures about 5 degrees above average.
This is a dynamic developing system. There are still uncertainties
about its exact track and development details. Environment Canada
will continue to monitor the development of this system closely and
update this statement accordingly and/or issue watches and warnings
if the rainfall amounts are significantly more than what is expected
at this time.
Listen for further statements. Additional information may also be
found by consulting the latest public forecast. The next public
forecast will be issued by 5 AM.
END/OSPC
Mine was.. 'Ridge pumping'
I'm aware of the other issues, which I choose not to believe were the cause.
Speaking of tactless...
America is on the decline, its a sad state of affairs, I will never be a lemming and follow the crowd, as millions of people continue to waste their lives in America. People here have become, weak, cold, selfish, lazy and unloving/ and or uncaring. I'm not putting that label by any means on all Americans. But there certainly is an increase in the amount of these traits in people.
Even worse Americans think we have some sort of magical advantage over others because "its America". No, its the hardworking and amazing people from all races and other nations from around the world that made America great. Now we have tons of people who do nothing but really mimic leaches by declining our nation. Then they boast that America is invincible because its just America. Once again, this horrible superiority complex is making America look horrible to the rest of the world, even more so because those who blast such information only make America degrade.
The fact is, America became great, and did become the worlds super power, but if things continue the way they are, that will not last a whole lot longer, if many people don't change big time.
Who said I was? I never do, but when they agree with me, I will mention them. It's always nice to have computer support. And waiting and seeing won't get us anywhere in seasonal forecasting. Lord knows our models surely won't.
Igor.
Seed maker DuPont Co., wind-turbine manufacturer General Electric Co. and insurer Zurich Financial Services AG are devising products to help the world adapt to climate change, a potential $135 billion-a-year market by 2030.
The companies are driven in part by the failure of international efforts to cut the greenhouse gases that scientists say contribute to global warming. Discussions last year in Copenhagen yielded little progress, and officials leading more than 190 countries in talks that begin today in Cancun, Mexico, say they don’t expect to achieve a binding agreement on measures to slow the growth of emissions.
Opens with some grim tones.
The hellish vision of a world warmed by 4C within a lifetime has been set out by an international team of scientists, who say the glacial progress of the global climate change talks that restart in Mexico today makes the so-called safe limit of 2C impossible to keep. A 4C rise in the planet's temperature would see severe droughts across the world and millions of migrants seeking refuge as their food supplies collapse.
I don't know exactly, but I would tend to think that weather here in Florida will not be as dry this winter, and it will be a little cooler then they predicted. This is because the weather this Fall has been dominated by weather patterns that reflect a normal winter, rather than La Nina. Thank God though, a warm dry winter is my worst nightmare. I like El Nino winters, lots of rain, and cold weather. I don't like Northern winters, but at the same time, I hate 80's in the winter here and endless sunny days. I like lots of active cold fronts with cold air and rainfall.
Anyway though, I'm not gonna make a prediction for the rest of the U.S. That's just too vast for me to attempt. But I do think Florida will experience more neutral weather conditions rather than warm and very dry.
Seconded.
Every track-deflecting trough.
I am 100% agreement with the information above that is posted, that is truly how science should be treated.
Please 'splain, Lucy. Or, use the Bat-phone.
Woohoo, buy their stock now!
Hmmmm ...
If I thought computer models were no good, it would be dishonest of me to cite them in support of my opinions.
They are not always wrong, and the reality is that if humans are right more often than the models on a general forecast, citing the models as support when they are right is not bad. Of course they will not always be correct, but give kudos to the models when they do get something right. Listing them as support of a forecast is just fine because they are right a good fraction of the time.
That was his explanation, actually. He explained it to one of the bloggers after he got his new site up. Can't find it now though. Batphone - ring ring!
There ya go. At least he didn't post in RED lol
Nah I wasn't accusing you of doing so, I just make statements like that to people. I am not actually making an accusation, if you know what I mean?
Anyways... Yeah, I really am only in this case disagreeing on Florida weather. I really don't see it being a super dry and super warm winter here in Central Florida. Of course, I'm not gonna be extreme and say it will be like the very cold and soggy El Nino winter we had last time here. I just believe we will have a more neutral winter here rather then La Nina like weather, like very dry and very warm.
Well computer models are more of great tools rather than forecasters themselves. Without them we would still have the the ignorance of the old days of meteorology. However, forecasters must not get lazy and let the models run the show for them and not put any effort. The forecaster must use his skill in how to use the computers in order to make the best forecast. Thank God we have computers that make millions of massive math equations and solve them in lightning amount of time.
Dang it, caught with a typo! I'll have to take out my "old eyes".
But basing your belief on the recent pattern could lead to - disappointment?
Ah excellent point...
+100
All I know is that the GFS for the last two runs has taken my Florida snowstorm away for Dec 8th... Maybe it'll bring it back on later runs. One can can always dream!
By the way, the upcoming system will bring very typical winter weather, rain, but not wild severe weather, and cool weather but not cold. At the same time, it doesn't follow La Nina weather either, which usually means no rain, massive outbreaks in fires, and lots of 80's in the winter.
OK, I fixed your typo in my reply too. Now nobody will ever know. ;-)
The Fish did good tho!
Exactly.
i noted that are H storm got upgrade too 70mph
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