Where's spring? 2nd most extreme March jet stream pattern on record extends winter

By: Dr. Jeff Masters , 3:15 PM GMT on March 20, 2013

Share this Blog
41
+

Punxatawney Phil got it way wrong. Pennsylvania's famous prognosticating rodent predicted just three more weeks of winter back on February 2. It's the first day of spring, but winter remains firmly entrenched over the eastern half of the U.S., where temperatures of 5 - 25°F below average have been the rule all week. The culprit is the jet stream, which has taken on an unusually contorted shape that is allowing cold air to spill down over the Eastern U.S. and Western Europe, but bringing near-record warmth to portions of Greenland. One measure of how contorted the jet stream has become is by measuring the difference in pressure between the Icelandic Low and the Azores High. There are two indices used to do this--one called the Arctic Oscillation (AO), which treats the flow over the entire Northern Hemisphere, and another called the North Atlantic Oscillation (NAO), which is more focused on the North Atlantic. The two are closely related about 90% of the time. When these indices are strongly negative, the pressure difference between the Icelandic Low and the Azores High is low. This results in a weaker jet stream, allowing it to take large, meandering loops, letting cold air to spill far to the south from the Arctic into the mid-latitudes. The AO index hit -5.2 today (March 20). This is the second most extreme March value of the index since record keeping began in 1948; only an AO value of -6.3 in March 1970 was more extreme. We've had some wildly variable jet stream patterns in recent years in the Northern Hemisphere. Just last year, we had the opposite extreme in March, when our ridiculous "Summer in March" heat wave brought a week of temperatures in the 80s to the Midwest U.S. The first day of spring today in Chicago, IL is expected to have a high temperature of just 25°F--a 60 degree difference from last year's high of 85°F on March 20!


Figure 1. The jet stream is taking a large dip to the south over the Eastern U.S., allowing cold air to spill southwards and bring winter-like conditions.

Unusual winter jet stream patterns tied to Arctic sea ice loss
Unusual jet stream contortions in winter have become increasingly common in recent years, according to a March 2013 paper by Tang et al., "Cold winter extremes in northern continents linked to Arctic sea ice loss". They found a mathematical relationship between wintertime Arctic sea ice loss and the increase in unusual jet stream patterns capable of bringing cold, snowy weather to the Eastern U.S., Western Europe, and East Asia, typical of what one sees during a strongly negative Arctic Oscillation. They theorized that sea ice loss in the Arctic promotes more evaporation, resulting in earlier snowfall in Siberia and other Arctic lands. The earlier snow insulates the soil, allowing the land to cool more rapidly. This results in a southwards shift of the jet stream and builds higher atmospheric pressures farther to the south, which increases the odds of cold spells and blocking high pressure systems that can cause extended periods of unusually cold and snowy weather in the mid-latitudes.

Related posts
From Heat Wave to Snowstorms, March Goes to Extremes by Andrew Freedman of Climate Central
Extreme jet stream causing record warmth in the east, record cold in the west (January 2013)
Arctic sea ice loss tied to unusual jet stream patterns (April 2012)
Our extreme weather: Arctic changes to blame? (December 2011)
Florida shivers; Hot Arctic-Cold Continents pattern is back (December 2010)
Jet stream moved northwards 270 miles in 22 years; climate change to blame? (June 2008)

I'll have a new post on Thursday.

Jeff Masters

()
Gusty Winds (novembergale)
High winds create huge waves behind ice dunes on Lake Erie this last day of winter.
Gusty Winds
After the blizzard (springsun)
Extreme severe winterconditions in the northeast of Germany, Kap Arkona. Source: wetterzentrale
After the blizzard

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 368 - 318

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13Blog Index

368. MTWX
Quoting VR46L:


Hope it stays that way !


Unfortunately I know it won't...

Our severe season, which usually runs from about Jan. 1st to the end of May, has been wierd this year. We are having fewer instances of severe weather, but those few have been on the extreme side. Take Monday's hail and 80 MPH wind gusts, and Hattiesburg's tornado last month for example...
Member Since: July 20, 2009 Posts: 23 Comments: 1393
351 Skyepony: Great pics. My favorite is this one by Alan Campbell in SW Brandon... That green in the sky really gives away the heavy hail...

Matches the skin tones of the Wicked Witch of the West. I wonder whether Oz's director had that particular weather phenomenum in mind while deciding upon her look.
Member Since: Posts: Comments:
Put me in for 15/7/2
Member Since: Posts: Comments:
Got cloudy outside. Looks like the NWS finally got the temperature forecast for the first time in a week right. Got to 53 like they said, then it has been steadily falling. Looks like I am in for some sprinkles, seeing light green on radar.

Good afternoon blog.
Member Since: Posts: Comments:
Quoting OrchidGrower:


Thanks, PBW! I've gotta get someplace where it does not freeze, so for now I guess The Villages are out of the running. After a little more warming, who knows?...
Leisureville, Boynton Beach Fl
Member Since: October 3, 2008 Posts: 0 Comments: 6000
363. VR46L
Quoting MTWX:


We are! Usually not hail this bad, but it has been surprisingly quiet, to be honest, so far this year...


Hope it stays that way !
Member Since: March 1, 2012 Posts: 0 Comments: 6971
362. MTWX
Quoting trHUrrIXC5MMX:


a nice green box with a check mark and the word "verified" next to your numbers...

:)


Sounds good!
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Member Since: Posts: Comments:
360. MTWX
Quoting VR46L:


Nope thats for sure ! but that area seems to be always in danger of severe weather.


We are! Usually not hail this bad, but it has been surprisingly quiet, to be honest, so far this year...
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Member Since: Posts: Comments:
Quoting MTWX:


We calling numbers for the season??

Put me down for 17-8-3...

Don't know why I picked those.. Just the first numbers that popped in my head... What do we get if we win??


a nice green box with a check mark and the word "verified" next to your numbers...

:)
Member Since: April 23, 2011 Posts: 104 Comments: 14873
Quoting hydrus:
I will when I can.


when you can? you can't know...?
what do you mean?
Member Since: April 23, 2011 Posts: 104 Comments: 14873
THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MARYLAND PORTION OF THE
CHESAPEAKE BAY...TIDAL POTOMAC RIVER...AND ADJACENT COUNTIES IN
CENTRAL MARYLAND AND NORTHERN VIRGINIA AS WELL AS THE DISTRICT OF
COLUMBIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

RAIN AND SNOW SHOWERS ARE POSSIBLE LATE THIS AFTERNOON AND
EVENING. A GALE WARNING IS IN EFFECT DURING THIS TIME WITH THE
POTENTIAL FOR THESE SHOWERS TO PRODUCE WIND GUSTS IN EXCESS OF 35
KT.
Member Since: Posts: Comments:
355. VR46L
Quoting MTWX:


I wouldn't either after Monday!!


Nope thats for sure ! but that area seems to be always in danger of severe weather.
Member Since: March 1, 2012 Posts: 0 Comments: 6971
354. MTWX
Quoting trHUrrIXC5MMX:
I have 33 bloggers( and one more to add in) listed in my hurricane score card as you probably saw

who else wants to participate??....feel free to tell me your numbers here or in my blog...


We calling numbers for the season??

Put me down for 17-8-3...

Don't know why I picked those.. Just the first numbers that popped in my head... What do we get if we win??
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Looks like the thunderstorm complex that has developed ahead of the trough about 75 miles west of Tampa is going to actually hold together as it approaches the coast unlike the last two rounds. Stability is decent, especially in areas that received a little more sun today.

I'm expecting a widespread 3/4", and the NWS seems to be thinking the same thing :)
Member Since: Posts: Comments:
Quoting trHUrrIXC5MMX:
I have 33 bloggers( and one more to add in) listed in my hurricane score card as you probably saw

who else wants to participate??....feel free to tell me your numbers here or in my blog...
I will when I can.
Member Since: Posts: Comments:
351. Skyepony (Mod)
Quoting MTWX:
More information and pictures from the storms Monday.


Great pics. My favorite is this one by Alan Campbell in SW Brandon..That green in the sky really gives away the heavy hail..

Member Since: Posts: Comments:
Friday has the potential to be a big day in eastern Texas. Instability is more than sufficient, dewpoints are forecast to be in the 60s, winds are from the south at the low-levels and west from the mid- to upper-levels, there is no cap, EHI values are well over 2, and lifted indices are under -5.

Skew-T and Hodo:



Member Since: Posts: Comments:
this isnt a cent fla soaking kinda rain :(.........
Member Since: Posts: Comments:
348. MTWX
Quoting VR46L:


From What I have observed of that office they don't take risks !


I wouldn't either after Monday!!
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Nam has the rain gone from florida by 10 pm..
Member Since: Posts: Comments:
346. VR46L
Quoting MTWX:
Even with the models still not quite agreeing on anything Jackson NWS just posted these...






Looks like we are primed for Round 2!!


From What I have observed of that office they don't take risks !
Member Since: March 1, 2012 Posts: 0 Comments: 6971
NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WITH LOCALLY HEAVY
RAINFALL ARE POSSIBLE THIS WEEKEND AS A FRONT LIKELY STALLS OVER
SOUTH GEORGIA.
Member Since: Posts: Comments:
I have 33 bloggers( and one more to add in) listed in my hurricane score card as you probably saw

who else wants to participate??....feel free to tell me your numbers here or in my blog...
Member Since: April 23, 2011 Posts: 104 Comments: 14873
343. VR46L
Quoting RitaEvac:


Wasn't that bad on the mainland, 110mph storm, the wind doesn't blow that hard, maybe in gusts but that's about it


Aye from what I heard Galveston took the worst of it but they got the pier back up last year from what I understand
Member Since: March 1, 2012 Posts: 0 Comments: 6971
342. MTWX
Even with the models still not quite agreeing on anything Jackson NWS just posted these...






Looks like we are primed for Round 2!!
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Quoting FtMyersgal:


Then why isn't your handle IkeEvac? :)


Matagorda Bay is further down the coast towards Corpus Christi. Hurricane Rita was predicted to strike the Galveston area (Galveston/Trinity Bay area) as very powerful hurricane and evacuations were called for in these areas. The hurricane weakened, but still a strong hurricane, and moved more to the east just before making landfall at Sabine Pass.


Map of area

The evacuation for Hurricane Rita in the Houston/Galveston areas was a snafu and many thousands of people were left trapped in traffic just north of Houston.

Rita exposes evacuation plan problems

Hurricane Rita's evacuations resulted in more deaths than the hurricane itself along the Texas coast line. Even with this, I consider the evacuation a requirement that was very poorly executed. (Houston/Galveston luckily "dodged the bullet") Had it no been for the weakening and changing of directions just before landfall, then Rita would have done a lot more damage than it did. And Rita did a lot of damage. I lost the roof of my house in Rita, but most likely to small tornado as opposed to the straight line winds from Rita.
Member Since: August 24, 2010 Posts: 0 Comments: 4764
from the radar,storms are moving ESE..........
Member Since: Posts: Comments:
Quoting aspectre:
blog2369comment1022 AGWcreationists: Tell me exactly how carbon emissions can be curtailed without a dramatic change to American lifestyles.

US 5,461,014,000tonnes of carbon emissions _ _ EU 4,177,817,000tonnes of carbon emissions
US 315,521,000 people _ _ _ _ _ _ _ _ _ _ _ _ _ _ EU 500,900,000 people
US 17.31tonnes per person _ _ _ _ _ _ _ _ _ _ _ _ EU 8.34tonnes per person


A much higher percentage of people in Europe live in cities, which were developed over several centuries. This lowers their average commuting distance significantly. Europe is much smaller, so the average distance to the ocean is much less,w hich means the average land distance for transport of materials for import or export is less.

The U.S. has much more total agriculture and forestry, which means lots of people live in rural areas, but need to drive to cities several times per week.

It's not possible to just magically cut out commuting or transport needs, unless we somehow had like twice as much automation and just canned that many jobs. Then we'd have ten times as much unemployment.

Another meaningless statics argument. It's easy to quote that without understanding why it is what it is.
Member Since: January 25, 2012 Posts: 33 Comments: 1520
Quoting PalmBeachWeather:
Orchid...Check out the Villages in central Florida


Thanks, PBW! I've gotta get someplace where it does not freeze, so for now I guess The Villages are out of the running. After a little more warming, who knows?...
Member Since: Posts: Comments:
Quoting schwankmoe:


I understand exactly what he's talking about. if variations in solar intensity correlate with variations in cosmic ray flux, then a shortening of the overall sun cycle with no change in the overall average will not raise the average cosmic ray flux. It will merely make the cycle in cosmc ray flux shorten, but not change the average.


True, dat.
Member Since: Posts: Comments:
might be an over night/morning kinda rain.....
Member Since: Posts: Comments:
335. MTWX
More information and pictures from the storms Monday.
Member Since: July 20, 2009 Posts: 23 Comments: 1393
Quoting VR46L:


Aye its coming 5 years now, hope you never have to go through that again !


Wasn't that bad on the mainland, 110mph storm, the wind doesn't blow that hard, maybe in gusts but that's about it
Member Since: July 14, 2008 Posts: 2 Comments: 9680
Quoting Tropicsweatherpr:


I posted my numbers there.


I don't see you there.. ???
Member Since: April 23, 2011 Posts: 104 Comments: 14873
Quoting yonzabam:


I think you misunderstand what's meant by 'cosmic rays' (although I haven't read the original post). Cosmic rays come from deep space. The solar wind deflects them.


I understand exactly what he's talking about. if variations in solar intensity correlate with variations in cosmic ray flux, then a shortening of the overall sun cycle with no change in the overall average will not raise the average cosmic ray flux. It will merely make the cycle in cosmc ray flux shorten, but not change the average.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
NWS as profile picture??
Member Since: April 23, 2011 Posts: 104 Comments: 14873
329. VR46L
Quoting RitaEvac:


Because I created the name RitaEvac before Ike hit.

If I waited 3 more months, I would of called myself IkeSurvivor, because I didn't evacuate


Aye its coming 5 years now, hope you never have to go through that again !
Member Since: March 1, 2012 Posts: 0 Comments: 6971
wont get any daytime heating,no sun all day here...
Member Since: Posts: Comments:
spring weather first month march april fatal bandary moving east of springfiled north east of cassvile outline
Member Since: Posts: Comments:
Member Since: Posts: Comments:
sure taking its time getting here..we need this rain...
Member Since: Posts: Comments:
Quoting aspectre:
blog2369comment1022 AGWcreationists: Tell me exactly how carbon emissions can be curtailed without a dramatic change to American lifestyles.

US 5,461,014,000tonnes of carbon emissions _ _ EU 4,177,817,000tonnes of carbon emissions
US 315,521,000 people _ _ _ _ _ _ _ _ _ _ _ _ _ _ EU 500,900,000 people
US 17.31tonnes per person _ _ _ _ _ _ _ _ _ _ _ _ EU 8.34tonnes per person


We pay over $10 a gallon for gas in the UK. Power bills have increased to the point where they're a major political issue. But it does keep down CO2 emissions.

Other reasons include hardly any air conditioning, and subsidized home insulation.
Member Since: Posts: Comments:
Quoting trHUrrIXC5MMX:
check my blog for the latest Hurricane score card....
thanks for the 33 people listed.

see comment #3 down the page there.


I posted my numbers there.
Member Since: Posts: Comments:
Thanks Wil
Great info.
Member Since: December 28, 2006 Posts: 115 Comments: 1599
Quoting FtMyersgal:


Then why isn't your handle IkeEvac? :)


Because I created the name RitaEvac before Ike hit.

If I waited 3 more months, I would of called myself IkeSurvivor, because I didn't evacuate.

Then everyone would think I was blown away on Galveston or Bolivar and survived a nightmare only to tell folks I had no damage, none what so ever.
Member Since: July 14, 2008 Posts: 2 Comments: 9680
Quoting OrchidGrower:


Having been clobbered twice by other drivers, including one hit-n-run, my fantasy is to live on an island where we all just drive golf carts. (Then I look at Congress and think, "heck, my fantasy is simply to RETIRE....")
Orchid...Check out the Villages in central Florida
Member Since: October 3, 2008 Posts: 0 Comments: 6000
blog2369comment1022 AGWcreationists: Tell me exactly how carbon emissions can be curtailed without a dramatic change to American lifestyles.
54 1911maker: Little CO2 reductions are not going to cut it. We need large, quick reductions of CO2 output. Not later, now. Can we do that with out a major shift in every ones lives?

US 5,461,014,000tonnes of carbon emissions _ _ EU 4,177,817,000tonnes of carbon emissions
US 315,521,000 people _ _ _ _ _ _ _ _ _ _ _ _ _ _ EU 500,900,000 people
US 17.31tonnes per person _ _ _ _ _ _ _ _ _ _ _ _ EU 8.34tonnes per person
Member Since: Posts: Comments:
Quoting MississippiWx:
I admit that I used to be a skeptic on AGW. I'm sure I've had a small debate with some of you, in fact. However, I realized that I'm not a scientist that dedicates my life to studying and researching the planet's climate. Therefore, how can I offer a differing opinion that really amounts to much? If we could truly get past the human element of debate and our egotistical mindset about who is right or wrong, we might could make more progress. Personally, I see nothing wrong with making our climate cleaner and healthier to live in, but maybe that's just me. Until then, our egos will remain more important than the climate in which we and future generations live.
Fortunately, you don't need to be a climate scientist to read a graph :)




And for those who prefer satellites...

Member Since: Posts: Comments:

Viewing: 368 - 318

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13Blog Index

Top of Page

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.

Local Weather

Overcast
31 °F
Overcast