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bluewave

Strongest NEPAC Block On Record 2013 Into 2014

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2013 will probably be remembered as the year of the record EPO region block.

This massive 500 mb block was the major driver of the weather patterns across

North America in 2013. 

 

 

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Your link shows a positive EPO.  bluewave is showing a negative EPO.

 

 

He is showing the loading pattern for a +EPO, so you just inverse it for a negative EPO....it requires the bulk of the height anomalies to be over Alaska....bluewave's map shows the bulk of the positive anomalies south of the typical EPO loading pattern. It is still a negative EPO, but not centered in the heart of the EPO region.

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He is showing the loading pattern for a +EPO, so you just inverse it for a negative EPO....it requires the bulk of the height anomalies to be over Alaska....bluewave's map shows the bulk of the positive anomalies south of the typical EPO loading pattern. It is still a negative EPO, but not centered in the heart of the EPO region.

 

Gotcha.

 

Question, what defines the EPO loading pattern as the "proper" or "right" spot.  How do we come up with it? 

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Gotcha.

 

Question, what defines the EPO loading pattern as the "proper" or "right" spot.  How do we come up with it? 

 

The loading patterns of various teleconnections (like EPO, NAO, PNA, etc) are based on the leading modes of variability over a specific domain (could be the Northern Hemisphere, Pacific+North America domain, Atlantic domain, etc). This is done through computing the EOFs of 500mb height (or SLP) climatology.

 

So then to calculate the daily index value, you project the daily 500mb height pattern onto the loading pattern. So basically when the current pattern matches the loading pattern, the projection will be positive, and when the current pattern is opposite the loading pattern, the projection will be negative.

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Even though the greatest 500 mb anomaly was skewed toward the southern side

of the EPO region, the ridge still set the record for EPO area even with the 

southern edge of the anomaly cut off.

 

 

 

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The loading patterns of various teleconnections (like EPO, NAO, PNA, etc) are based on the leading modes of variability over a specific domain (could be the Northern Hemisphere, Pacific+North America domain, Atlantic domain, etc). This is done through computing the EOFs of 500mb height (or SLP) climatology.

 

So then to calculate the daily index value, you project the daily 500mb height pattern onto the loading pattern. So basically when the current pattern matches the loading pattern, the projection will be positive, and when the current pattern is opposite the loading pattern, the projection will be negative.

 

 

I get that.  But how do we define what the domain will be for these patterns when the atmosphere is so variable and fluid? 

 

I hope I make sense.

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I get that.  But how do we define what the domain will be for these patterns when the atmosphere is so variable and fluid? 

 

I hope I make sense.

 

The indices describe specific patterns that reoccur over time that impact temperature and precipitation in definable ways for

certain geographic regions. The massive ridge near the EPO region this year lead to record drought on the West Coast

along with a quick drought reversal over the Southeast. The Arctic cold entering the U.S. along with record warmth over

Alaska was all part of this pattern.

 

This year was just a very extreme version of a precipitation pattern that you would expect from a -EPO. Notice how the drought expanded further south and was historic along the West Coast

due to the ridge extending further south.

 

 

 

 

The ESRL site has a range of maps that you can create for positive and negative phases.

So a map for one phase will be reversed for the other phase.

 

http://www.esrl.noaa.gov/psd/data/correlation/

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If San Fransisco gets less than 1/4 of rain it will be the driest January on record. According to the GFS, they make it.  Also record highs and fire danger.

 

Here's the articles from Wunderground Blogs.

 

http://www.wunderground.com/news/california-records-highs-fire-danger-drought-20140113

 

http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=233

115.jpg

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LOL...OH my god... 

 

 

 

Your link shows a positive EPO.  bluewave is showing a negative EPO.

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  the   -EPO  / -WPO    doesnt matter ....   the  AO is super  positive   well   has been  super  positive there  this  winter is   going to     blow torch

 

  any day now   now

 

  no wait .. this time we really mean it  

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If San Fransisco gets less than 1/4 of rain it will be the driest January on record. According to the GFS, they make it.  Also record highs and fire danger.

 

Here's the articles from Wunderground Blogs.

 

http://www.wunderground.com/news/california-records-highs-fire-danger-drought-20140113

 

http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=233

115.jpg

 

Driest year on record for California with an expansion of extreme drought conditions on the recent update.

 

http://www.mercurynews.com/science/ci_24904396/california-drought-whats-causing-it

 

 

As California struggles through a run of historically dry weather, most residents are looking at falling reservoir levels, dusty air and thirsty lawns.

But meteorologists have fixed their attention on the scientific phenomenon they say is to blame for the emerging drought: a vast zone of high pressure in the atmosphere off the West Coast, nearly four miles high and 2,000 miles long, so stubborn that one researcher has dubbed it the "Ridiculously Resilient Ridge."

Like a brick wall, the mass of high pressure air has been blocking Pacific winter storms from coming ashore in California, deflecting them up into Alaska and British Columbia, even delivering rain and cold weather to the East Coast. Similar high-pressure zones pop up all the time during most winters, but they usually break down, allowing rain to get through to California. This one, ominously, has anchored itself for 13 months, since December 2012, making it unprecedented in modern weather records and leaving researchers scratching their heads.

"It's like the Sierra -- a mountain range just sitting off the West Coast -- only bigger," said Bob Benjamin, a forecaster with the National Weather Service in Monterey. "This ridge is sort of a mountain in the atmosphere. In most years, it comes and goes. This year it came and didn't go."

 
 

 

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If it's this bad now, I can't imagine how bad it will get during next fall's Santa Ana season (assuming this pattern continues for the rest of this rainy season).

Looks to be a neural to slightly negative PAN for the month of Feb. Rain chances should increase.

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And on the other side of the coin the Block has allowed us here in the Great Lakes to see our snowiest month ever

 

And the second and third coldest winter on record to date for Northern Minnesota.

 

http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=dlh&storyid=99873&source=0

 

 

So far this Winter Season (December 1st through January 26th) of 2013-2014, International Falls ranks as the 3rd coldest on record.  Duluth is tied for the 2nd Coldest Average temperature for the Winter Season. The following is a list of the top 3 coldest winter seasons to date at International Falls and Duluth.

International Falls

1.  -4.8 degrees average temperature from December 1, 1978 through January 26, 1979

2.  -4.1 degrees average temperature from December 1, 1976 through January 26, 1977

3.  -3.5 degrees average temperature from December 1, 2013 through January 26, 2014

 

Duluth

1. 2.7 degrees average temperature from December 1, 1976 through January 26, 1977

2. 3.8 degrees average temperature from December 1,  2013 through January 26, 2014

2. 3.8 degrees average temperature from December 1, 1917 through January 26, 1918

 

 

 

 

 

 

 

 

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And the second and third coldest winter on record to date for Northern Minnesota.

 

http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=dlh&storyid=99873&source=0

 

 

So far this Winter Season (December 1st through January 26th) of 2013-2014, International Falls ranks as the 3rd coldest on record.  Duluth is tied for the 2nd Coldest Average temperature for the Winter Season. The following is a list of the top 3 coldest winter seasons to date at International Falls and Duluth.

International Falls

1.  -4.8 degrees average temperature from December 1, 1978 through January 26, 1979

2.  -4.1 degrees average temperature from December 1, 1976 through January 26, 1977

3.  -3.5 degrees average temperature from December 1, 2013 through January 26, 2014

 

Duluth

1. 2.7 degrees average temperature from December 1, 1976 through January 26, 1977

2. 3.8 degrees average temperature from December 1,  2013 through January 26, 2014

2. 3.8 degrees average temperature from December 1, 1917 through January 26, 1918

 

attachicon.gif145.gif

 

attachicon.gifT.gif

 

 

 

 

 

 

 

 

Wow... that December cold snap is still showing up as a minor cold anomaly on the map!  That will probably be eaten away by warmer anomalies by the end of winter...

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