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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See y'all later. I still do not have power...at least 2000 people in North Nashville are without power. Good thing is the temperature is below 75. Plus my computer's battery is drained so bye everyone. Until power is restored. :(
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Derived from the 10July6amGMT (NHC) ATCF data for HurricaneEmilia:
Its vector had held steady at 9.2mph(14.8km/h) WNWest
MaxSusWinds had decreased from 115knots(132mph)213km/h to 110knots(127mph)204km/h
And minimum pressure had increased from 950millibars to 953millibars

For those who like to visually track H.Emilia's path...
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 KaimuBeach
10July12pmGMT: H.Emilia had been headed toward passing over NanawaleEstates
10July6pmGMT: H.Emilia was heading toward passing over ParadisePark in ~12days6hours

Copy&paste 19.384n154.934w, 19.518n154.807w, 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, 13.6n113.3w-19.624n154.949w into the GreatCircleMapper for more information
The previous mapping for comparison
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1269. LargoFl
Quoting StormTracker2K:


Seabreeze collision happened right over downtown Tampa. You guys will probably get 3" to 4" of rain out of this.

cannot believe the thunder, like a war zone right now
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Quoting #1253 Tribucanes


It can be hard to tell if anyone is sarcastic on the internet... Wish there was a way to see everyone's faces while discussing on various forums or blogs... no more trolls hiding in the dark or sentences interpreted wrongly. Wouldn't that be something??
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Quoting StormTracker2K:


Seabreeze collision happened right over downtown Tampa. You guys will probably get 3" to 4" of rain out of this.



didnt you just have a storm roll through?
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Eye is clearer than earlier with a small burst of convection just south of it.

Member Since: July 6, 2010 Posts: 113 Comments: 32830
Back for a little bit then gone till 8.
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Quoting Patrap:
<--- Bowing out gracefully to walk the dog n da park of Audubon.


Uptown, New Orleans
Elevation

20 ft

Station Select
Now

Light Rain
Temperature
77.7 F
Feels Like 80 F


Take care buddy!
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Quoting Patrap:
<--- Bowing out gracefully to walk the dog n da park of Audubon.


Uptown, New Orleans
Elevation

20 ft

Station Select
Now

Light Rain
Temperature
77.7 F
Feels Like 80 F


Thanks for pointing out your location loco
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Quoting Jedkins01:
Getting absolutely hammered here, radar does not do this cell justice, constant thunder, rain gauge rainfall rate has been between 2 and 4 inches per hour, and I'm getting gusts of 40 to 50 mph here. This small cell in Pinellas went from a shower to a full blown mature cell in just the last 2 minutes.


Seabreeze collision happened right over downtown Tampa. You guys will probably get 3" to 4" of rain out of this.

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1261. LargoFl
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Coincedence?
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting Jedkins01:
Getting absolutely hammered here, radar does not do this cell justice, constant thunder, rain gauge rainfall rate has been between 2 and 4 inches per hour, and I'm getting gusts of 40 to 50 mph here. This small cell in Pinellas went from a shower to a full blown mature cell in just the last 2 minutes.


Do you have a rain gauge?
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Quoting Patrap:
<--- Bowing out gracefully to walk the dog n da park of Audubon.

New Orleans Weather at a Glance

Weather Station - report

Uptown, New Orleans
Elevation

20 ft

Station Select
Now

Light Rain
Temperature
77.7 °F
Feels Like 80 °F


Sounds very nice for a July afternoon!
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1257. Patrap
<--- Bowing out gracefully to walk the dog n da park of Audubon.


Uptown, New Orleans
Elevation

20 ft

Station Select
Now

Light Rain
Temperature
77.7 F
Feels Like 80 F
Member Since: July 3, 2005 Posts: 428 Comments: 129844
1256. LargoFl
Quoting Jedkins01:
Getting absolutely hammered here, radar does not do this cell justice, constant thunder, rain gauge rainfall rate has been between 2 and 4 inches per hour, and I'm getting gusts of 40 to 50 mph here. This small cell in Pinellas went from a shower to a full blown mature cell in just the last 2 minutes.
..yes this is a bad one alright
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1255. LargoFl
..geez just tons of lightning and thunder like cannonfire lol..just hope we dont get a tornado or two out of this line coming at us
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1254. Patrap
When I quote someone's image I usually use a #1251 for example
Member Since: July 3, 2005 Posts: 428 Comments: 129844
Patrap's humor is not for all that's for sure. Several offended by his Florida word play. He's bitingly sarcastic with some of his friends and they give sarcasm to each other in healthy doses. I thought he and Rita didn't like each other earlier with their banter. That's all it was though, banter. I think it's better to ask one's intent when reading something like Patrap's Florida word play. If I recall correctly, at least three dropped Patrap a line saying they were not amused by his Florida word play. At the same time I know Patrap has good relationships with many, many from Florida here, I never took it as seriously intent. If one's not familiar with Patrap though it would be very easy to take his comments out of context. And yes, when irked he can become rather condescending. One of the best for posting here though, lots of great info I've really appreciated from Patrap.
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Getting absolutely hammered here, radar does not do this cell justice, constant thunder, rain gauge rainfall rate has been between 2 and 4 inches per hour, and I'm getting gusts of 40 to 50 mph here. This small cell in Pinellas went from a shower to a full blown mature cell in just the last 2 minutes.
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Getting a few pop ups here now.

Member Since: August 2, 2006 Posts: 47 Comments: 11709
Quoting TropicalAnalystwx13:
I live where the red + is. Lot's of lightning and heavy rain, but hail isn't a threat thankfully. Not large hail anyways.

Near Wilmington NC I guess..........Love the little town of Southport and Bald Head Island
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1249. Patrap
Quoting icmoore:


You go any way you like I prefer the quote feature...it makes it much easier to understand when you are trying to read back and catch up on the blog.


It does and it has its place..but we can remind others here now that you cant quote a image, nor radar, unless you grab the HTML out the quote and use the image button to show it.




Member Since: July 3, 2005 Posts: 428 Comments: 129844
It looks like the Bermuda Ridge will be splitting in two!!! With the West High going towards the Carolina's and the East High reconsolidating around the East Atlantic.
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I live where the red + is. Lot's of lightning and heavy rain, but hail isn't a threat thankfully. Not large hail anyways.

Member Since: July 6, 2010 Posts: 113 Comments: 32830
Hail here in Tampa. I'm off Martin Luther King, about 2miles west of I75
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Quoting TropicalAnalystwx13:

Rocky Point. Not really a city though lol.


if i were guessing, you live on a point. that is rocky.
Member Since: June 17, 2011 Posts: 11 Comments: 6539
1244. Patrap
Member Since: July 3, 2005 Posts: 428 Comments: 129844
Quoting TropicalAnalystwx13:

Rocky Point. Not really a city though lol.
Now for my stupid question Trop.....What state?
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1242. LargoFl
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1241. icmoore
Quoting Patrap:
If you feel you've been offended.


I heartliy apologise.

But relaying logic is not talking down unless you expected it.

I didnt quote anyone.


You did.

Dats how we got here.

Ill be going with post numbers in the futcha'..as the quote feature is overused ad nauseum.

I liked it better when we had to copy and paste and italicize.


You go any way you like I prefer the quote feature...it makes it much easier to understand when you are trying to read back and catch up on the blog.
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Quoting PalmBeachWeather:
What city are you in Trop?

Rocky Point. Not really a city though lol.
Member Since: July 6, 2010 Posts: 113 Comments: 32830
Quoting TropicalAnalystwx13:
Lightning and thunder is really going off here. The bolts are hitting close too because you can here the crackle.
What city are you in Trop?
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Quoting weatherh98:
is this what we are thinking?


Yep

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Lightning and thunder is really going off here. The bolts are hitting close too because you can here the crackle.
Member Since: July 6, 2010 Posts: 113 Comments: 32830
Quoting ProgressivePulse:


Yeah, that's a pretty classic "dangerous" set up for the Peninsula and the Gulf Coast. Good thing is that timing is on our side at the moment.

Oh yes!
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1235. Patrap
Tazaroo, Pin-Hole, definitely.



Member Since: July 3, 2005 Posts: 428 Comments: 129844
1234. bappit
Quoting BaltimoreBrian:



It sounds to me like VR46L is saying that people who believe manmade global warming is a serous problem use computers that use electricity. Therefore global warming doesn't exist.
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Quoting opal92nwf:

I thought so. We really have had our share of recurving storms the last few years, a pattern like that can only hold for so long.


Yeah, that's a pretty classic "dangerous" set up for the Peninsula and the Gulf Coast. Good thing is that timing is on our side at the moment.
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is this what we are thinking?
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting LargoFl:
..yeah the rest of the week its supposed to be heavier storms they say

This is the scientific forecast discussion.

Convective coverage will continue the trend of recent days and
increase over the next couple, especially across our eastern zones.
The broad diffuse upper trough to our west will continue to enhance
convection on its southern and eastern periphery as it remains
nearly stationary. Water vapor imagery indicates a vort center over
the southeast Gulf of Mexico just northwest of the western tip of
Cuba. This feature has also been generating quite a bit of
convection. The surface reflection is a weak trough extending from
the Yucatan northeast to the southwest coast of Florida. Most of the
models bring this feature northwestward as the open wave it
currently is. The NAM develops the system into a deepening low and
then brings it to the coast near Mobile on Friday.
This is an
outlier solution, and considering this model's tendencies with
developing tropical features, it will be discounted. Nevertheless,
the trough will bring increasing moisture into the region. Low to
mid level flow will be out of the south-southeast (local sea breeze
regime type 6). This is a high pop regime. Everything therefore
points to a wet forecast. Pops on Wednesday will be in the likely
range across our Florida zones and 50 to the north. Add about 10 percent
on Thursday. The abundant clouds and numerous showers will keep
temps a bit cooler than recent days with highs generally in the
lower 90s. Lows will be in the lower 70s. Both these numbers are
very near climo.
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1229. bappit
Quoting BaltimoreBrian:


I don't like it either. I sort of assumed that it took in data from a few years before and a few years after each year. But with the final few years in the graph the binomial line being based on assumptions about what future temperatures will be. Not rigorous. But I'm not sure.

See if Dr. Masters will answer :)

So I looked it up on the internet. This is my source.

"Statisticians have borrowed several terms from the jargon of electrical engineering, and sometimes speak of a sequence of data as being %u201Cnoisy%u201D. This implies that the observations consist of two parts; a underlying signal (a meaningful pattern of variation), and a superimposed noise (a random variation with little meaning). These expressions are most likely to be encountered in time series problems, because research on radio-signal analysis has contributed greatly to this branch of statistics. In geophysics the smoothing process usually is known as filtering, and the mathematical equation describing the smoothing calculation is called a filter.

"The idea that a meaningful message is submerged in the mixture of often confusing data that a meteorologist accumulates is an appealing one, and attempts to apply time series techniques to meteorological and climatologically data are becoming increasingly prevalent.

"Electrical engineers have developed a number of techniques for enhancing a signal with respect to noise. Noise is short-term, and fluctuates rapidly. Signals, in contrast, tend to be long-term. In other words, successive values of the signal usually are autocorrelated, whereas noise at one point is completely independent of noise at adjacent points. As the signal tends to be the same from one point to nearby point and the noise does not, an average of several adjacent points will tend to converge on the value of the signal alone.

"The most obvious type of data smoothing is a simple moving average, but other calculations may be adopted instead. The moving average is calculated as the sum of N observations, divided by N (N should be an odd number), plotted at the central year in the observation series. By this, a 3-yr moving temperature average is calculated as the sum of temperatures three years in a row, divided by three, and the resulting average value plotted at the interval midpoint year. The interval midpoint year is also called the estimated point or year. It should be noted that, because the smoothing interval extends N/2 years on either side of the estimated year, the moving average cannot be computed for points at the beginning and at the end of the data sequence considered. If N is 11 years, for example, a smoothed estimate cannot be computed for the first five or last five years in a sequence. In other words, a uniformly smoothed graph can never extend all the way to the endpoints of the data series considered."

Edit: but a moving average is not a binomial filter.
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Grown up adult children
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1227. LargoFl
............................hey Stormtracker..you be Careful out there..52 mph wind gusts..thats a strong storm
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Quoting icmoore:


You don't need to talk down to me or explain about the blog's features I understand.


Put down the monkey food and walk away...
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1225. Patrap


Member Since: July 3, 2005 Posts: 428 Comments: 129844
This lightning is just unreal. it is striking literally every second right now.

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1223. LargoFl
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1222. Patrap

991
WUUS52 KILM 102006
SVRILM
NCC129-102030-
/O.NEW.KILM.SV.W.0117.120710T2006Z-120710T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE WILMINGTON NC
406 PM EDT TUE JUL 10 2012

THE NATIONAL WEATHER SERVICE IN WILMINGTON NC HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHERN NEW HANOVER COUNTY IN SOUTHEAST NORTH CAROLINA

* UNTIL 430 PM EDT

* AT 405 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
OF 60 MPH. THIS STORM WAS LOCATED NEAR SILVER LAKE...OR NEAR
WILMINGTON...AND MOVING EAST AT 10 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO...
MASONBORO...
SEAGATE...

MORE DANGEROUS THUNDERSTORMS MAY DEVELOP AND AFFECT OTHER COMMUNITIES
IN THE WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING AND HEAVY RAIN. FOR YOUR
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME
OR BUSINESS.



PLEASE REPORT HAIL...DOWNED TREES OR DAMAGING WINDS TO THE NATIONAL
WEATHER SERVICE IN WILMINGTON NC...TOLL FREE AT 877-633-6772...WHEN
YOU CAN DO SO SAFELY.

LAT...LON 3409 7786 3408 7786 3406 7787 3407 7793
3413 7794 3422 7794 3422 7780
TIME...MOT...LOC 2006Z 272DEG 8KT 3414 7790
Member Since: July 3, 2005 Posts: 428 Comments: 129844
1221. LargoFl
..just got soaked walking the dogs but the worst is just nearing me
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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