The U.S. and European cold blast: blame the NAO

By: Dr. Jeff Masters , 4:00 PM GMT on January 07, 2010

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The Deep South shivered through another frigid morning today, with low temperature records crumbling again over much of Florida. Lakeland hit 27°F, smashing the old record of 34°F; Melbourne hit 28°F, eclipsing the old record of 32°F; and West Palm Beach bottomed out at 37°F, besting the old record of 38°F. The cold wave is being driven by an unusual sharp and persistent kink in the jet stream that is being blocked from moving by a strong ridge of high pressure over Greenland. As a result, an exceptionally strong surface high pressure of 1055 mb over the North Central U.S. is pushing large amounts of cold, Arctic air southwards from Canada. No coldest January temperature records have been set yet from the cold blast, but the 500 largest U.S. cities have been averaging about 11 new daily low temperature records per day the first five days of January, according to the National Climatic Data Center. The cold will ease Friday in the Deep South, but return with a vengeance Saturday night though Monday morning, as another push of cold air descending from Canada promises to bring a cold wave that will approach the December 1989 and January 1977 cold waves in intensity, and may being some new all-time January low temperature records to the South.

Colder in Florida than Alaska and Greenland
The sharp kink in the jet stream has brought record warm temperatures to a few stations in Alaska and the Pacific Northwest this week, making much of coastal Alaska warmer than Florida. Cold Bay, Alaska, set a record high yesterday of 47°F, after recording a low temperature of 30°F. This made Cold Bay warmer than Pensacola, Florida, which had a high of 47°F and a low of 24°F. In fact, most of Florida--including Jacksonville, Tampa, Melbourne, and Tallahassee--recorded lows at or below the 27°F low recorded in Anchorage, Alaska yesterday. The jet stream kink has also brought temperatures more than 30°F above average to Greenland. The temperature in Narsarsuaq, Greenland at 10am EST today was 46°F, far warmer than most of Florida.


Figure 1. Departure of the surface temperature from average for the first three day of 2010 shows much colder than average conditions were present over the Southeast U.S., much of Europe, and Central Asia. Much warmer than average temperatures were present over the Northwest U.S., Greenland, the Arctic, and Southern Asia. A sharp kink in the jet stream was responsible for the temperature anomaly pattern. Image credit: NOAA/ESRL.

Snow in Florida?
It doesn't snow very often in Florida, and the Wikipedia list of snow events in Florida lists only seven such events over the decade of the 2000s. This weekend's cold wave may be able to generate some snow over isolated regions of Central Florida, though it appears that the odds of this happening are less than 30%. The most widespread snowfall in Florida history occurred on January 19, 1977, when snow fell over much of the state, with flurries as far south as Homestead. Snow flurries also fell on Miami Beach for the only time in recorded history.


Figure 2. North Atlantic Oscillation (NAO) index for September 9, 2009 - January 6, 2010 (black line) and forecast from the GFS model (red lines). The NAO index was strongly negative, near -2.0, for much of December and January. Image credit: NOAA/CPC.

The winter cold blast: blame the North Atlantic Oscillation (NAO)
Why has the winter been so cold over Eastern North America and northern Europe? Well, don't blame El Niño. El Niño winters are rarely this cold. Instead, blame the the North Atlantic Oscillation (NAO). The 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 has seen a very strong negative NAO, causing much of our cold weather over Eastern North America and Europe. The NAO index for the month of December 2009 was -1.93, which is the third lowest NAO index since 1950 for a winter month (December, January, or February). The only winter months with a lower NAO index were February 1978 (-2.20) and January 1963 (-2.12). January 1963 was one of the coldest months on record in the UK and the Eastern U.S.. February 1978 was the coldest February on record for five U.S. states, and featured the historic blizzards in both the U.S. and UK. The NAO so far for January 2010 has continued to stay strongly negative, ranging between -1.5 and -2.1. However, the blocking ridge over Greenland is forecast to weaken next week, allowing the sharp kink in the jet stream to straighten out. This will increase the NAO index to more typical values, allowing a return of more ordinary winter weather to the U.S. and Europe.

Jeff Masters

From The Porch 1 (suzi46)
from our porch view of sunrise this morning..totally different from the 'splendiferous' shots 1-8 taken from the top of our field overlooking the mountains
From The Porch 1
First snow (Rowdyblue)
of winter in South Mississippi.
First snow
Wind blown snow (bikesnapper)
Like sand dunes or Antelope Canyon
Wind blown snow

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Quoting GeoffreyWPB:


Not at all. You were very accurate in your forecast. I hope the warming trend holds true for a little while. At least reach our average temps.


A recap on the "unknown precipitation" discussion you missed on Saturday..

We have "unknown precipitation" several times a year. I gave it a nickname of "SLOP", which is a combination of snow, sleet, rain, drizzle all at once!

There is:
SNEET- snow and sleet
SNIZZLE-snow and drizzle
SNAIN-snow and rain
FRIZZLE-freezing rain and drizzle
FRIZSNEET-freezing rain, drizzle, sleet and snow


Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting PensacolaDoug:


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2977. Patrap
re: #2973.

Money isnt always the objective in relief work.

It's more a matter of the heart.

And your words speak volumes of the kindness in yours.

I thank you for them here from portlight, gregpinehurstnc.



Member Since: July 3, 2005 Posts: 423 Comments: 127804
Quoting beell:
Incredible Tree Climbing Goats of Morocco

Is it true?


I'm sure that anyone who has raised goats can testify to their incredible athletic abilities. They can leap from a standing position to a narrow wall several feet over their heads, balance on it and then leap to another site. Trees or mountainsides - should make no difference.
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Quoting PcolaDan:


This is getting old fast. Flip flops and socks just don't make a good fashion statement.

But that's made up for by your AbFab Bar Mitzvah boy picture in your avatar!
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Quoting Bordonaro:


Geoff, I know that you probably wanna kick my butt! I just knew this Arctic outbreak would go above and beyond the call of duty!!

If it's any consolation, it was 16F Fri morn, 13F Sat morn and 17F on Sun morn and my electric bill doubled and then some!! And 58 hrs straight below 32F.


Your aware the only problem with temps below 32... it makes the greens harder to read.
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if i did not say so b4,, what you all did for that family,went far into the realm of donating, it was an act of love for a family,,, .i am sorry i did not havve the means to give yall any money at that time, work starts back here in march,, i know 10 $ aint alot,,golf season starts, and the touristas, start playing, and spending..i will send it,
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Quoting PensacolaDoug:


This is getting old fast. Flip flops and socks just don't make a good fashion statement.
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Quoting Bordonaro:


Geoff, I know that you probably wanna kick my butt! I just knew this Arctic outbreak would go above and beyond the call of duty!!

If it's any consolation, it was 16F Fri morn, 13F Sat morn and 17F on Sun morn and my electric bill doubled and then some!! And 58 hrs straight below 32F.


Not at all. You were very accurate in your forecast. I hope the warming trend holds true for a little while. At least reach our average temps.
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Lafayette, Purdue University Airport
Lat: 40.43 Lon: -86.93 Elev: 623
Last Update on Jan 10, 8:54 pm EST

Clear

16 °F
(-9 °C)
Humidity: 62 %
Wind Speed: SW 9 MPH
Barometer: 30.29"
Dewpoint: 5 °F (-15 °C)
Wind Chill: 4 °F (-16 °C)
Visibility: 10.00 mi.


Temperature has risen 4 degrees in the last 2 hours with the approaching Alberta Clipper
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Quoting GeoffreyWPB:


In 2040...bloggers will be asking "What is Fresca?" :)


Geoff, I know that you probably wanna kick my butt! I just knew this Arctic outbreak would go above and beyond the call of duty!!

If it's any consolation, it was 16F Fri morn, 13F Sat morn and 17F on Sun morn and my electric bill doubled and then some!! And 58
hrs straight below 32F

Member Since: August 25, 2009 Posts: 20 Comments: 6785
PBIA 40...Wind Chill 32
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Quoting Patrap:
LOL AIM,,Im gonna booty that Pic..

Im the one on the left,as usual,..and note the Swizzle stick too.



LOL, it's just a tiny disappointment that the donkey isn't on the left, doh! It's all yours...
there's other goat & donkey books, btw...but this cover is the best, imo.
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2964. jipmg
They are forecasting a colder morning tomorrow in miami..

some areas in inland dade could see 20s..

and metro areas are forecasted to be in the low 30s, miami specifically 33..

old record was 37
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2963. KEEPEROFTHEGATE (Mod)
Quoting Bordonaro:


Is this storm going to tap any Arctic Air?? I sure hope not!


no on the 850 looks too cool down a bit but not that much with a quick building warm rtn flow


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2962. Patrap
Quoting GeoffreyWPB:


In 2040...bloggers will be asking "What is Fresca?" :)


I'll have a Link fer them WPB,

U betcha..!'
Member Since: July 3, 2005 Posts: 423 Comments: 127804
Quoting Bordonaro:


Is this storm going to tap any Arctic Air?? I sure hope not!


I'm afraid so(though how much is still in the air).
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2960. Patrap
LOL AIM,,Im gonna booty that Pic..

Im the one on the left,as usual,..and note the Swizzle stick too.

Member Since: July 3, 2005 Posts: 423 Comments: 127804
what is any ones idea on that system next friday?if it flurried in orlando its got to do it here,,lol. fyi, my sis had a time share in orlando, next week, i told her to cancel , all the smart people here,i said , i aint payin, 4$, for 2 minutes, in that human dryer,,for us to stand in it all day and just look,
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Quoting Patrap:
Wow..just realized I'll be 80 in Jan 2040.

And most likely watching the clock as my Main Blog BANN slowly winds down,..

..again.



In 2040...bloggers will be asking "What is Fresca?" :)
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Quoting Patrap:
I spent 6 Hours in a Car with atmoaggie on a fine Mission ,..2 weeks ago this Weds,

He's a Fine dude and One I'd follow into Hades door if asked.

Happy B-day to Him come tomorrow.


You're both fine dudes! I'm not sure why, but this book really reminded me of your Mission to CatAdjuster...except you both should be Goats! :)



When Goat offers to do the grocery shopping, Donkey knows that things might just get a little muddled! He writes out a list so that Goat will know exactly what to buy. But the market is such a dazzling place and Goat sees so many lovely things. Instead of apples, carrots, cabbages and ice cream, Goat buys a sun hat, an inflatable octopus, a trumpet and a pair of sunglasses decorated with strawberries! What ever will Donkey make of all the surprises that Goat has in his basket when he trots triumphantly back home? Goodness knows!
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Quoting weatherbro:


A classic Miller A Type system(or at least a coastal huger). Watch out for severe thunderstorms over the Florida Peninsula and blizzard conditions from The Central Gulf Coast straight to Bean Town!

I wonder, does anyone got model projections on how strong and where the 93 storm was headed(as opposed to what actually occurred)? That'd be interesting.


Is this storm going to tap any Arctic Air?? I sure hope not!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
2955. Patrap
Wow..just realized I'll be 80 in Jan 2040.

And most likely watching the clock as my Main Blog BANN slowly winds down,..

..again.

Member Since: July 3, 2005 Posts: 423 Comments: 127804
Quoting weatherbro:


That's three straight days I've seen them forecast this potential superstorm to the exact position and intensity! Could this be her twin 17 years later?!!


A classic Miller A Type system(or at least a coastal huger). Watch out for severe thunderstorms over the Florida Peninsula and blizzard conditions from The Central Gulf Coast straight to Bean Town!

I wonder, does anyone got model projections on how strong and where the 93 storm was headed(as opposed to what actually occurred)? That'd be interesting.
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Quoting GeoffreyWPB:


That "depends"....awful joke...I should ban myself :(
Quoting Orcasystems:


Is that where you have been finding those.. you should WU him the link.


You guys are killing me, ROFLMBAO.
Hubby can't figure it out; he thinks I'm laughing at the Simpson's 20th Anniversary show but it's not that funny.
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2951. Patrap
I spent 6 Hours in a Car with atmoaggie on a fine Mission ,..2 weeks ago this Weds,

He's a Fine dude and One I'd follow into Hades door if asked.

Happy B-day to Him come tomorrow.
Member Since: July 3, 2005 Posts: 423 Comments: 127804
Quoting weatherbro:


That's three straight days I've seen them forecast this potential superstorm to the exact position and intensity! Could this be her twin 17 years later?!!


It doesn't appear to be as powerful, so, we'll see; I guess.
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2949. KEEPEROFTHEGATE (Mod)
Quoting AussieStorm:
Has anyone seen this monster for you guys next week....

ya aussie should know better in a few more runs waitin on 00z

here what i am looking at for the system shows dev beginning at the 96 hr peaking out at the 120 hr and beyond

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Quoting AussieStorm:
Has anyone seen this monster for you guys next week....



That's three straight days I've seen them forecast this potential superstorm to the exact position and intensity! Could this be her twin 17 years later?!!
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Quoting AwakeInMaryland:


I'm going to miss browsing Bed, Bath and Beyond for pics.


Is that where you have been finding those.. you should WU him the link.
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Quoting AwakeInMaryland:


Geoff, this is really, really funny.

Except I am suddenly despressed realizing that 30 years from now, Matt T-Dude will still be younger than I am now.

Would you be able to give me a lift in the Hovercraft and drop me off at the Revitalization Center?

AtmoAggie's Birthday is tomorrow, right? This Capricorn jag is depleting the store of Goat pics. Kudos to whomever posted the pic of the goats in the tree!


That "depends"....awful joke...I should ban myself :(
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Quoting Orcasystems:


To easy.. I expected better :(


I'm going to miss browsing Bed, Bath and Beyond for pics.
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Quoting drg0dOwnCountry:
Out Of Balance
How ExoonMobile impacts climate change (ground zero).
Sue ExxonMobile for crimes against humanity!

Link


Link
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Quoting gordydunnot:
I dont know about that but you are certainly quick. 2 minutes amazing.


Thats what his wife said :)
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Quoting GeoffreyWPB:


I can just imagine this blog thirty years from now...

1089 GeoffreyWPB 6:48 PM EST on January 10, 2040

Can't believe it's snowing in West Palm. I remember vaguely that last two times it snowed in south Florida, in 1977 and 2010. Gotta run and take the hovercraft to the super store. Gosh, mid-air collision insurance costs so much these days. If I see any snow, I'll take a picture with my bionic eye cam. Well, let me run my teeth through the dishwasher so I look good. BTW, yes eddye, you will school tomorrow, and on a side note, I think Director of NHC JFV is going a little overboard with his constant forecasts for a Cat. 5 Fla. strike. But I like the way he decorated his office with little fishes and things. Oh, and happy belated 49th B-Day Matt (:


Geoff, this is really, really funny.

Except I am suddenly despressed realizing that 30 years from now, Matt T-Dude will still be younger than I am now.

Would you be able to give me a lift in the Hovercraft and drop me off at the Revitalization Center?

AtmoAggie's Birthday is tomorrow, right? This Capricorn jag is depleting the store of Goat pics. Kudos to whomever posted the pic of the goats in the tree!
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Quoting KEEPEROFTHEGATE:
my wife always tells me i have second sight

It was the happy face wasn't it?
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2940. KEEPEROFTHEGATE (Mod)
its all good hello fla dano
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Quoting KEEPEROFTHEGATE:
my wife always tells me i have second sight


:)
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The giveaway is when you mention JFV....he always asks....Who is JFV? He does it everytime.
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I dont know about that but you are certainly quick. 2 minutes amazing.
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2936. KEEPEROFTHEGATE (Mod)
Quoting gordydunnot:
Keeper you should see if you can get a job with CSI Miami.
my wife always tells me i have second sight
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Keeper you should see if you can get a job with CSI Miami.
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Has anyone seen this monster for you guys next week....

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Hey KOG, you have some mail ha
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Quoting KEEPEROFTHEGATE:
that was easy


To easy.. I expected better :(
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Quoting Floridano:


Swell, yourself?


same thanks, so how's the cold treating ya?
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Freeze in Florida Tonight Will Be Worst Since 1989

So far, citrus-growers in Florida have gotten by with only light damage following several nights of sub-freezing temperatures over the past week. Tonight will likely prove more destructive as temperatures drop to the lowest levels in over 20 years. (more)
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2929. KEEPEROFTHEGATE (Mod)
Quoting Orcasystems:
He's back :)
that was easy
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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.