U.S. experiences warmest 12-month period on record--again

By: Dr. Jeff Masters , 9:04 PM GMT on July 09, 2012

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Thanks in part to the historic heat wave that demolished thousands of high temperature records at the end of June, temperatures in the contiguous U.S. were the warmest on record over the past twelve months and for the year-to-date period of January - June, said NOAA's National Climatic Data Center (NCDC) on Monday. June 2012 was the 14th warmest June on record, so was not as extreme overall as March 2012 (first warmest March on record), April (third warmest April), or May (second warmest May.) However, temperatures were warm enough in June to set a new U.S. record for hottest 12-month period for the third straight month, narrowly eclipsing the record set just the previous month. The past thirteen months have featured America's 2nd warmest summer (in 2011), 4th warmest winter, and warmest spring on record. Twenty-six states were record warm for the 12-month period, and an additional sixteen states were top-ten warm. The year-to-date period of January - June was the warmest on record by an unusually large margin--1.2°F.


Figure 1. This time series shows the five warmest years that the contiguous U.S. has experienced, and how the year-to-date temperature evolved each month throughout those years. The time series also shows the 2012 year-to-date temperature through June, which was the warmest first half of any year on record for the lower 48. The 2012 data are still preliminary. Image credit: NOAA/NCDC.


Figure 2. Four of the top-ten warmest 12-month periods in the contiguous U.S. since 1895 have occurred since April 2011. Image credit: NOAA/NCDC.

Most extreme January - June period on record
NOAA's U.S. Climate Extremes Index (CEI), which tracks the percentage area of the contiguous U.S. experiencing top-10% and bottom-10% extremes in temperature, precipitation, and drought, was 44% during the year-to-date January - June period. This is the highest value since CEI record-keeping began in 1910, and more than twice the average value. Remarkably, 83% of the contiguous U.S. had maximum temperatures that were in the warmest 10% historically during the first six months of 2012, and 70% of the U.S. of the U.S. had warm minimum temperatures in the top 10%. The percentage area of the U.S. experiencing top-10% drought conditions was 20%, which was the 14th greatest since 1910. Extremes in 1-day spring heavy precipitation events were near average.


Figure 3. NOAA's U.S. Climate Extremes Index (CEI) for January - June shows that 2012 has had the most extreme first six months of the year on record, with 44% of the contiguous U.S. experiencing top-10% extreme weather.

Tuesday Webinar on the future of extreme weather impacts on business
I'm presenting a 12-minute Webinar talk on the future of weather-related disasters at 2 pm EDT Tuesday July 10. If you want to register (it's free) and listen in, visit the propertycasualty360.com web site. The title of the webinar is, "The Year-Round CAT Season: Is Your Business Prepared for Increasingly Frequent Severe Weather?"

"New McCarthyism" targets climate scientists
Bill Blakemore with ABC News has an interesting five-part interview with climate scientist Dr. Michael Mann, where Dr. Mann explains how a "New McCarthyism" is targeting climate scientists. I reviewed Dr. Mann's excellent book, "The Hockey Stick and the Climate Wars", earlier this year.

A 1 in 1.6 million event?
I originally wrote in this post that "Each of the 13 months from June 2011 through June 2012 ranked among the warmest third of their historical distribution for the first time in the 1895 - present record. According to NCDC, the odds of this occurring randomly during any particular month are 1 in 1,594,323. Thus, we should only see one more 13-month period so warm between now and 124,652 AD--assuming the climate is staying the same as it did during the past 118 years."

It has been pointed out to me that the calculation of a 1 in 1.6 million chance of occurrence (based on taking the number 1/3 and raising it to the 13th power) would be true only if each month had no correlation to the next month. Since weather patterns tend to persist, they are not truly random from one month to the next. Thus, the odds of such an event occurring are greater than 1 in 1.6 million--but are still very rare. I appreciate hearing from those of you who wrote to point out a correction was needed.

Jeff Masters

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1921. ScottLincoln
11:24 PM GMT on July 11, 2012
Quoting Neapolitan:
There's an excellent in-depth dissection/discussion of the Esper et al paper over on RealClimate.org. In brief, while the reconstruction is welcomed both for its finer precision at certain timescales and its handling of the so-called divergence problem, the paper's authors may be slightly overstating their conclusions. What's most exciting, however, is that tree ring data corroborate instrumental data; the rapid warming since 1900 is readily apparent in both records.


This has been starting to make the rounds quickly already, I'm glad RealClimate addressed it. I've seen news articles already misunderstanding the conclusions or seeing what they want to see. It doesn't prove anything, it doesn't refute anything. As with any single study, it suggests; for this study it suggests a steeper natural warming trend since the Roman Warm Period than some other studies. Contrary to some poorer analysis, it actually suggests that the modern warming period halted and reversed a more substantial natural cooling, thus providing even more evidence for significance of our enhanced greenhouse effect.
Member Since: September 28, 2002 Posts: 5 Comments: 2870
1920. VINNY04
3:47 PM GMT on July 11, 2012
Quoting Autistic2:
Any one know why my quote button would stop working?
it happend to me yesterday. it seems to happen alot you just have to wait for the next comment page to pop up.
Member Since: March 6, 2011 Posts: 0 Comments: 243
1919. Some1Has2BtheRookie
2:16 PM GMT on July 11, 2012
Deleted
Member Since: August 24, 2010 Posts: 0 Comments: 4728
1918. Xyrus2000
2:15 PM GMT on July 11, 2012
Quoting JupiterKen:


Too bad you are not a scientist. These temperatures are well within their average for this date. Always the alarmist.


Well within range? According to who?

Resolute, Canada was in the 60's and 70's. That is well above normal for this time of year, or any time of year for that matter. Similar conditions existed across the arctic, where temperature anomalies where anywhere from 5 to 10+ degrees above normal. Further, SST anomalies are also indicate much above normal temperatures for a lot of the arctic.

And if you don't want to believe temperature and sensor measurements, then how about some visual imagery? MODIS imagery of the arctic shows the rapid melting, and clearly shows the fractured and slush like nature of the western half of the ice (which will soon be melting away completely.

Here's a site that shows you every metric you'd care to look at in regards to the arctic: Link .

It's quite likely we will see a new minimum extent this year, and pretty much certain that we will hit a new low for volume (the more important number). But you can continue pretending that nothing is happening.
Member Since: October 31, 2009 Posts: 0 Comments: 1224
1917. hydrus
2:10 PM GMT on July 11, 2012
Quoting Patrap:
The K storm came together on 05 near this Miami thingee.


Dis is B-A-D Mojo,
Moving over Miami W-SW too.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
1916. Some1Has2BtheRookie
2:01 PM GMT on July 11, 2012
Deleted
Member Since: August 24, 2010 Posts: 0 Comments: 4728
1915. StormTracker2K
1:55 PM GMT on July 11, 2012
Quoting Patrap:
The K storm came together on 05 near this Miami thingee.


Dis is B-A-D Mojo,



Some on here don't get it Pat. This systems can form fast in the area especially with steering favoring a Rita or K track.
Member Since: October 26, 2011 Posts: 0 Comments: 2651
1914. WunderAlertBot (Admin)
1:54 PM GMT on July 11, 2012
JeffMasters has created a new entry.
1913. Xyrus2000
1:52 PM GMT on July 11, 2012
Quoting spathy:
"exactly how a changing climate will impact specific elements of weather, such as clouds",
Like clouds that can cool the temps.
They dont even know how that type of feedback will unfold in the future.
Or they ignore it.


No GCM I'm aware of ignores clouds, nor are scientists ignorant of what kinds of feedbacks can result from clouds in the future.

What makes clouds so difficult is that, for the most part, clouds are very small scale phenomena, and even the highest resolution coupled models can only capture the larger events. The other problem is that clouds are a meteorological phenomena and depend greatly on the prevailing conditions, terrain, etc. so any cloud component of such models usually have error bars associated with them.

This is why scientists do thousands of runs with these models using slight variations of parameters to get a good feel about where the climate is going. And depending on where and how often the clouds form, they can have cooling or a warming effect. And even if they have a warming or cooling effect that does not imply that the planet will get warmer or cooler, as clouds are just one part of these models. It is not simply "more clouds == more cooling" like certain internet personalities would like you to believe.

And even if the models say something is going to happen does not mean the scientists automatically assume it will. The models are a result of science, not vice versa. The models are tools that can help provide insight into the climate system. They are not the end-all, be-all of climate science, and no credible climate scientist would ever claim such a thing.

The climate is not simple. In a number of cases, it isn't even intuitive. There is a considerable amount of advanced physics and mathematics that go into climate science; math and science that are used in a number of other fields. A skeptic understands the math and science, and attempts to find weaknesses and holes in the prevailing science using rigor and analysis. Deniers would have you believe that they can rip apart scientific results using grade school math and excel spreadsheets.
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1912. Patrap
1:52 PM GMT on July 11, 2012
The K storm came together on 05 near this Miami thingee.


Dis is B-A-D Mojo,
Member Since: July 3, 2005 Posts: 414 Comments: 125530
1911. Neapolitan
1:52 PM GMT on July 11, 2012
Quoting fireflymom:
Interesting article on climate research from Northern Europe going back to 138BC.  Easy read and most interesting.




Climate in Northern Europe Reconstructed for the Past 2,000 Years: Cooling Trend Calculated Precisely for the First Time  http://www.sciencedaily.com/releases/2012/07/12070 9092606.htm

There's an excellent in-depth dissection/discussion of the Esper et al paper over on RealClimate.org. In brief, while the reconstruction is welcomed both for its finer precision at certain timescales and its handling of the so-called divergence problem, the paper's authors may be slightly overstating their conclusions. What's most exciting, however, is that tree ring data corroborate instrumental data; the rapid warming since 1900 is readily apparent in both records.
Member Since: November 8, 2009 Posts: 4 Comments: 13260
1910. LargoFl
1:51 PM GMT on July 11, 2012
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1909. aspectre
1:51 PM GMT on July 11, 2012
Derived from the 11July12pmGMT (NHC) ATCF data for HurricaneEmilia:
14.3n115.1w - 14.5n116.2w has been re-evalutated&altered
14.2n115.1w - 14.5n116.2w - 14.7n117.0w are now the most recent positions

Its vector had changed from 12.7mph(20.5km/h) WNWest to 9.2mph(14.8km/h) WNWest
MaxSusWinds had had held steady at 90knots(104mph)167km/h
And minimum pressure had held steady at 970millibars

For those who like to visually track H.Emilia's path...
OGG is Kahului :: ITO is Hilo :: SAN is SanDiego ::CSL is CaboSanLucas

Easternmost dot on the connected line-segments is where TropicalStormEmilia became H.Emilia
Westernmost dot on the connected line-segments is HurricaneEmilia's most recent position

The longest line is a straightline projection thru H.Emilias's 2 most recent positions to the coastline
10July6pmGMT: H.Emilia had been headed toward passing over ParadisePark
11July12amGMT: H.Emilia had been headed toward passing 217miles(349kilometres) north of Kauai
(Closest passage at 25.369n159.021w. Not shown due to map scale)
11July6amGMT: H.Emilia had been headed toward passing over Pe'ahi,Maui
11July12pmGMT: H.Emilia was heading toward passing 1.1miles(1.7kilometres) North of TheBigIsland
in ~11days15hours

Copy&paste ogg, 19.624n154.949w, 25.369n159.021w, 20.943n156.279w, ito, 8.8n156.2w, san, csl, 12.0n108.7w-12.4n109.4w, 12.4n109.4w-12.8n110.5w, 12.8n110.5w-13.2n111.7w, 13.2n111.7w-13.4n112.5w, 13.4n112.5w-13.6n113.3w, 13.6n113.3w-13.8n114.1w, 13.8n114.1w-14.2n115.1w, 14.2n115.1w-14.5n116.2w, 14.5n116.2w-14.7n117.0w, 14.5n116.2w-20.284n155.85w, 20.268n155.85w-20.284n155.85w into the GreatCircleMapper for more information
The previous mapping for comparison
Member Since: August 21, 2007 Posts: 0 Comments: 4860
1908. RitaEvac
1:51 PM GMT on July 11, 2012
Mornin, sport
Member Since: July 14, 2008 Posts: 1 Comments: 9625
1907. weathermanwannabe
1:49 PM GMT on July 11, 2012
Just east of Miami:

Station FWYF1
NDBC
Location: 25.591N 80.097W
Date: Wed, 11 Jul 2012 13:00:00 UTC

Winds: NE (40°) at 11.1 kt gusting to 13.0 kt
Atmospheric Pressure: 30.05 in and rising
Air Temperature: 75.2 F
Water Temperature: 84.6 F


Just east of Key Largo:

Station MLRF1
NDBC
Location: 25.012N 80.376W
Date: Wed, 11 Jul 2012 13:00:00 UTC

Winds: NE (40°) at 13.0 kt gusting to 14.0 kt
Atmospheric Pressure: 30.05 in and rising
Air Temperature: 77.4 F
Water Temperature: 82.8 F
View Details - View History

I guess the science loses this morning.

See Yall Later................... :)
Member Since: August 8, 2006 Posts: 0 Comments: 8269
1906. LargoFl
1:49 PM GMT on July 11, 2012
...............................stormtracker, all of this will be up by us later on today,whew
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1905. jeffs713
1:47 PM GMT on July 11, 2012
Quoting StormTracker2K:
People can say what they want but this is definitely sustaining convection and infact it appears to be growing in size!



Looks impressive on the visible sat.

Which would make sense considering its proximity to a ULL (providing lift) and divergent flow aloft (providing ventilation). That doesn't mean it is anything worthy of special note.
Member Since: August 3, 2008 Posts: 16 Comments: 5792
1904. Patrap
1:47 PM GMT on July 11, 2012
Refresh your browser, or re-start the system
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1903. LargoFl
1:47 PM GMT on July 11, 2012
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1902. Autistic2
1:46 PM GMT on July 11, 2012
Any one know why my quote button would stop working?
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1901. washingtonian115
1:44 PM GMT on July 11, 2012
Quoting ncstorm:
wow..what is that in the Atlantic..

I can't see it.
Quoting ncstorm:


thats scary that it only took about that short enough time for it flood cars and basements..
The clouds were a darkish green looking color yesterday.i had to check the weather report to see if we weren't under a tornado watch or something.Lol.The storms exploded when they got near the city.Luckly not that much thunder or lightning.We had some good wind.Measured a wind of 35mph.
Member Since: August 14, 2010 Posts: 10 Comments: 15707
1900. LargoFl
1:44 PM GMT on July 11, 2012
.....................amazing how there are no serious warnings yet down there
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1899. StormTracker2K
1:44 PM GMT on July 11, 2012
Low is forming off SE FL. These rain bands of rain are building all the back toward Nassua,Bahamas.
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1898. BrickellBreeze
1:44 PM GMT on July 11, 2012
Quoting StormTracker2K:
People can say what they want but this is definitely sustaining convection and infact it appears to be growing in size!



Looks impressive on the visible sat.


Anyone else see some rotation?
Member Since: March 22, 2012 Posts: 0 Comments: 723
1897. Patrap
1:43 PM GMT on July 11, 2012
Growing in numbers
Growing in speed
Can't fight the future
Can't fight what I see

People they come together
People they fall apart
No one can stop us now
'Cause we are all made of stars

Lessons of lovers
Left in my mind
I sing in the reaches
We'll see what we find



Member Since: July 3, 2005 Posts: 414 Comments: 125530
1896. fireflymom
1:43 PM GMT on July 11, 2012
Interesting article on climate research from Northern Europe going back to 138BC.  Easy read and most interesting.




Climate in Northern Europe Reconstructed for the Past 2,000 Years: Cooling Trend Calculated Precisely for the First Time  http://www.sciencedaily.com/releases/2012/07/12070 9092606.htm

Member Since: June 5, 2007 Posts: 0 Comments: 573
1895. hydrus
1:43 PM GMT on July 11, 2012
Quoting Grothar:


People can call it what they want; a baroclinic low, a tutt, a ULL, a front. Speaking scientifically, that is definetly a blob.

It does look like hurricane season wth those blobs on da pics.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
1894. weathermanwannabe
1:43 PM GMT on July 11, 2012
Nothing wrong with calling out the Blobs but it's the science behind the Blobs that is important.
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1893. Grothar
1:43 PM GMT on July 11, 2012
Quoting jeffs713:

What if the baroclinic low associated with the ULL to the east that is being influenced by the front to its north and the TUTT cell to its east doesn't want to be called a blob? What if it wants to be called a mass? Hmmmmm?


I like when you talk technical! LOL
Member Since: July 17, 2009 Posts: 63 Comments: 23703
1892. GeorgiaStormz
1:42 PM GMT on July 11, 2012
Wont leave this up for long, problably has been posted already by my trolly brother:

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1891. ncstorm
1:42 PM GMT on July 11, 2012
Quoting jeffs713:

The ULL at the center of the TUTT.


thanks!
Member Since: August 19, 2006 Posts: 13 Comments: 13441
1890. Patrap
1:42 PM GMT on July 11, 2012
Member Since: July 3, 2005 Posts: 414 Comments: 125530
1889. StormTracker2K
1:41 PM GMT on July 11, 2012
People can say what they want but this is definitely sustaining convection and infact it appears to be growing in size!



Looks impressive on the visible sat.
Member Since: October 26, 2011 Posts: 0 Comments: 2651
1888. Patrap
1:41 PM GMT on July 11, 2012
Member Since: July 3, 2005 Posts: 414 Comments: 125530
1887. jeffs713
1:41 PM GMT on July 11, 2012
Quoting ncstorm:
wow..what is that in the Atlantic..


The ULL at the center of the TUTT.
Member Since: August 3, 2008 Posts: 16 Comments: 5792
1886. LargoFl
1:40 PM GMT on July 11, 2012
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1885. ncstorm
1:40 PM GMT on July 11, 2012
Quoting washingtonian115:
Yes it came down hard for about 20 minutes.Yes we need for our drought.Bur not all at once.Could have more storms today.


thats scary that it only took about that short enough time for it flood cars and basements..
Member Since: August 19, 2006 Posts: 13 Comments: 13441
1884. LargoFl
1:40 PM GMT on July 11, 2012
Quoting Grothar:


People can call it what they want; a baroclinic low, a tutt, a ULL, a front. Speaking scientifically, that is definetly a blob.

..looks like miami is getting hammered
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1883. jeffs713
1:40 PM GMT on July 11, 2012
Quoting Grothar:


People can call it what they want; a baroclinic low, a tutt, a ULL, a front. Speaking scientifically, that is definetly a blob.


What if the baroclinic low associated with the ULL to the east that is being influenced by the front to its north and the TUTT cell to its east doesn't want to be called a blob? What if it wants to be called a mass? Hmmmmm?
Member Since: August 3, 2008 Posts: 16 Comments: 5792
1882. ncstorm
1:38 PM GMT on July 11, 2012
wow..what is that in the Atlantic..

Member Since: August 19, 2006 Posts: 13 Comments: 13441
1881. hydrus
1:38 PM GMT on July 11, 2012
Quoting Patrap:
G' morning wunderland
Good morning Pat.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
1880. Grothar
1:38 PM GMT on July 11, 2012
Quoting washingtonian115:
Blobs,blobs....and more blobs!!.


People can call it what they want; a baroclinic low, a tutt, a ULL, a front. Speaking scientifically, that is definetly a blob.

Member Since: July 17, 2009 Posts: 63 Comments: 23703
1879. LargoFl
1:37 PM GMT on July 11, 2012
.............this time of year we really have to watch these tropical waves coming across
Member Since: August 6, 2011 Posts: 4 Comments: 33283
1878. washingtonian115
1:36 PM GMT on July 11, 2012
Quoting ncstorm:


Yeah I saw on TWC last night that DC storm drains couldnt handle the heavy rains last night and a lot of basements were flooded out..unfortunately, the rain is supposed to last well into Monday for the east coast..
Yes it came down hard for about 20 minutes.Yes we need for our drought.Bur not all at once.Could have more storms today.
Member Since: August 14, 2010 Posts: 10 Comments: 15707
1877. LargoFl
1:36 PM GMT on July 11, 2012
Quoting StormTracker2K:


It's already lightning over here and it has gotten black just over the last 10 minutes.
..ok still mostly sunny here with some overcast in area's,just got back from clearwater beach, its real busy now with alot of people there,hope they are watching the skies, going to turn bad later on
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1876. GeoffreyWPB
1:34 PM GMT on July 11, 2012
Member Since: September 10, 2007 Posts: 0 Comments: 10577
1875. StormTracker2K
1:33 PM GMT on July 11, 2012
Quoting LargoFl:
..oh man we are in for it today


It's already lightning over here and it has gotten black just over the last 10 minutes.
Member Since: October 26, 2011 Posts: 0 Comments: 2651
1874. jeffs713
1:32 PM GMT on July 11, 2012
Quoting weathermanwannabe:


Thanks Jeff. I was the party pooper on the Florida blob but was waiting on someone from your parts to handle the Texas blob.......... :)

My pleasure. I do not discriminate. I rain on everyone's parade (pun intended).
Member Since: August 3, 2008 Posts: 16 Comments: 5792
1873. jeffs713
1:31 PM GMT on July 11, 2012
Quoting StormTracker2K:


It's very weak but as you can see something is trying to get going here.


"Very weak" meaning no 850mb vort, a ULL a couple hundred miles to the east, and thunderstorm activity being driven by upper-level divergence? (Check Link)
Member Since: August 3, 2008 Posts: 16 Comments: 5792
1872. ncstorm
1:31 PM GMT on July 11, 2012
Quoting StormTracker2K:



Yeah this area from SE TX up to NC is in for a deluge over the next several days due to a stalled frontal boundry.


Yeah I saw on TWC last night that DC storm drains couldnt handle the heavy rains last night and a lot of basements were flooded out..unfortunately, the rain is supposed to last well into Monday for the east coast..
Member Since: August 19, 2006 Posts: 13 Comments: 13441
1871. weathermanwannabe
1:30 PM GMT on July 11, 2012
Quoting jeffs713:
Huh? I'm in Houston (heck, that "swirl" is less than 10 miles from my house), and that is anything but "well defined". It is a kinda-sorta-really-not-organized MCS trying to get going. No swirl. No tropical entity forming. Not necessary for watching closely.

If we start watching that closely, we might as well start watching each individual thunderstorm that forms in the MDR.


Thanks Jeffs. I was the party pooper on the Florida blob but was waiting on someone from your parts to handle the Texas blob.......... :)
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About JeffMasters

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