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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Quoting wxchaser97:
TS Jose

Any similarities
TS Daniel


Daniel is more bigger...lol
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Quoting HurricaneHunterJoe:


I tink so


Looking at the loops 98E has gotten a lot more organized recently and should be bumped up to 90% or more next TWO.
Member Since: September 3, 2011 Posts: 13 Comments: 3477
Dry Thunderstorm Threat for the Northern Rockies
A disturbance moving through the Northwestern U.S. has the potential to kick off isolated thunderstorms across the northern Rockies. These thunderstorms will likely produce little precipitation. Should a lightning strike spark a fire amid the dry and gusty conditions of the northern Rockies, fire could spread quickly. Link
Member Since: March 16, 2012 Posts: 127 Comments: 7972
Quoting WxGeekVA:




Future Fabio


I tink so
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Quoting wxchaser97:
Dead Daniel


Extreme Emilia


She still has some very nice towers
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1615. Buhdog
HMmmmmmm, here is in Cape Coral (swfl) low level clouds are streaming south? Wonder if a low is forming south or east of us.
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TS Jose

Any similarities
TS Daniel
Member Since: March 16, 2012 Posts: 127 Comments: 7972

Quoting OneDrop:
The mosquitoes are the worst I've seen in 25 years. I used to be a fishing guide in Everglades National Park and I have never seen anything like it this year. You can here them coming when you approach a mangrove island to fish and they are hungry!! Here in Volusia county in NE Florida, they are so friggin' bad that they've sprayed 3 times in my neighborhood since late May.


Anyone in here from Naples FL right now? When I lived there they used to fly the DC-3'S over the city with a diesel/whatever insecticide they used to kill em. Kinda like Robert Duval smelling the napalm in Apocalypse Now and saying " It smells like victory".
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Quoting wxchaser97:
Dead Daniel


Extreme Emilia




Future Fabio
Member Since: September 3, 2011 Posts: 13 Comments: 3477
11/0000 UTC 15.4N 137.6W T1.5/2.5 DANIEL -- East Pacific
11/0000 UTC 14.2N 115.1W T4.5/5.0 EMILIA -- East Pacific

Member Since: March 16, 2012 Posts: 127 Comments: 7972
1610. Sangria
Great pics, Jedkins.....thought it was bad sitting in my house.....would have hated to be driving in it, this afternoon.....
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Dead Daniel


Extreme Emilia
Member Since: March 16, 2012 Posts: 127 Comments: 7972
Hmmm... looks like we're going to get some more rain tonight...



G'night, all.

Enjoy the rest of the evening.
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Quoting spathy:


The mixup in the atmosphere sure caused some wicked CL> Gr lightning. I was waiting for the vibrations to break a window at any moment. 20 sec rumblings and instant shock-waves were relentless for an hr or so.
Awsome!

Sure sounds scary cool.
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This was headed north to Speech class this afternoon, this thunderstorm had a severe thunderstorm warning at the time. In the first photo there is a strong updraft beneath the thick wall cloud/outflow boundary, it had some weak rotation and was hanging very low, although it looked pretty creepy it never gained any organization, thankfully that atmosphere isn't too favorable for tornadoes, however these nasty sea breeze collisions can sometimes spin up weak tornadoes from low level shearing.

The second photo was a wall cloud formation extending out from the cell before I drove beneath it.
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Quoting Grothar:


Thank you.



LOL
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Quoting LargoFl:
..hopefully all your lakes etc will finally fill up, i know alot of folks over there were really worried just a month or two ago, good luck with your rains

I can't wait to read the rain gauges-- we just got what I swear was 3" in 30mins right on top of Lake Travis. That hasn't happened in.. almost two years. It's weird. Feels like when you have a water interruption that lasts and lasts and then suddenly cuts back on and every faucet in your house starts blasting!
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1601. OneDrop
Quoting AllBoardedUp:
Does the rain in Florida bring out the mosquitoes like it does here on the Texas coast? They have been horrible here the entire summer so far. Of course the high tides coming up farther in the marsh doesn't help either.
The mosquitoes are the worst I've seen in 25 years. I used to be a fishing guide in Everglades National Park and I have never seen anything like it this year. You can here them coming when you approach a mangrove island to fish and they are hungry!! Here in Volusia county in NE Florida, they are so friggin' bad that they've sprayed 3 times in my neighborhood since late May.
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Quoting spathy:

Hi San
Thats what it looked like to me,but yesterday it sure Got my eye!
Spathy how'd you come up with your user name?.
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1598. VINNY04
Quoting Tygor:
4th night in a row in San Antonio where the rain has somehow missed us. Thunder and lightning all around but nary a drop falling.
i feel your pain. it happens to us in tampa too.
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1597. ncstorm
OBX-looks something maybe trying to develop..

good vorticity.


Tropical Cyclone Formation
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1596. Tygor
4th night in a row in San Antonio where the rain has somehow missed us. Thunder and lightning all around but nary a drop falling.
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Quoting Grothar:


Thank you.


:O
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Quoting TheOnlyBravesFan:
I know I'm kinda off-topic ( at least it looks that way), but I couldn't resist sharing this. I'm at a summer weather camp here in D.C. and some of us campers just "happened" to notice the sky getting greener, and then saw a rotating wall cloud. This is the video we shot.

Howard University Wall Cloud
It's weather..so it's not off topic.But the sky was sort of a darkish green.Then it started to rain and at first normal..then hard for at least 20 minutes.I saw a few lightning strikes with with a rumble of thunder or two.I did measure a wind of 35mph.Hubby said he recorded one at 40mph.
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1591. VINNY04
Quoting Jedkins01:


It sure is!


I was on earlier reporting the storm as it started but then I stopped suddenly, I'm ok and everything is fine here just to let everyone know, I stopped reporting because i had to leave for school.

We had nearly 2 inches of rain today, gusts over 40 mph at times near 50. But the most impressive part of all was definitely the lightning. My gosh, I haven't seen that many close lightning hits in a while definitely the most impressive lightning so far this year.


Honestly this might be the first time in a long while we are seeing the classic summer time pattern in Florida. Although this weather might seem rather "freakish" it's not at all. Strong to severe thunderstorms that bring wind damage, flooding and freakish lighting is a common thing around here. We just haven't had this pattern n a while so it seems unusually but we are really seeing a more classic Florida summer. It's great to see it back!

It's not that we haven't had enough rain in recent years during the rainy season, its just that the past few days we had more just showery rainy weather instead of this pattern like this where we get powerful thunderstorms that produce incredible lightning shows almost every. We still got them but they were fewer the past few years than what i grew up with.


Well, they're back!

yah i missed this weather. heres to a productive lightning season!!!!!
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Quoting AllBoardedUp:
Does the rain in Florida bring out the mosquitoes like it does here on the Texas coast? They have been horrible here the entire summer so far. Of course the high tides coming up farther in the marsh doesn't help either.


Mosquitoes are absolutely brutal here around Tampa Bay. I have gotten torn up at 2 PM during hot sun while working on my car, at night they are even worse, you literally have to RUN to get away from them, they'll chase you down!

They were surprisingly pretty bad even during the severe drought before Debby. But the 12 inch plus widespread rain amounts and overall a wet June after such a severe drought must have stimulated the mosquitoes even more than normal. Because I get eaten up every time I'm outside.
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1589. Grothar
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1588. Grothar
Quoting HurricaneHunterJoe:


Good Artist


Thank you.
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Quoting GTcooliebai:
over 7000 lightning strikes with the line of storms that came through here, looks like FL. summertime pattern is back!


It sure is!


I was on earlier reporting the storm as it started but then I stopped suddenly, I'm ok and everything is fine here just to let everyone know, I stopped reporting because i had to leave for school.

We had nearly 2 inches of rain today, gusts over 40 mph at times near 50. But the most impressive part of all was definitely the lightning. My gosh, I haven't seen that many close lightning hits in a while definitely the most impressive lightning so far this year.


Honestly this might be the first time in a long while we are seeing the classic summer time pattern in Florida. Although this weather might seem rather "freakish" it's not at all. Strong to severe thunderstorms that bring wind damage, flooding and freakish lighting is a common thing around here. We just haven't had this pattern n a while so it seems unusually but we are really seeing a more classic Florida summer. It's great to see it back!

It's not that we haven't had enough rain in recent years during the rainy season, its just that the past few days we had more just showery rainy weather instead of this pattern like this where we get powerful thunderstorms that produce incredible lightning shows almost every. We still got them but they were fewer the past few years than what i grew up with.


Well, they're back!

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1586. Sangria
Quoting spathy:

Piddly only because it not piddling around my doorstep.
I just love fish storms.
Has anyone mentioned the convergent spinning off my SWFL coast?
I dont think it can do anything bad but it sure sparks my interest.


Hiya Spathy......have watched it most of the day....around 24N/86W.....it's an ULL, and does not look to be working it's way down any, so don't think anything will happen with it....
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I know I'm kinda off-topic ( at least it looks that way), but I couldn't resist sharing this. I'm at a summer weather camp here in D.C. and some of us campers just "happened" to notice the sky getting greener, and then saw a rotating wall cloud. This is the video we shot.

Howard University Wall Cloud
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Quoting ncstorm:
lots of boomers..

still getting pounded at OBX. Is something developing of the NC coast?
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1583. Grothar
Quoting spathy:

Piddly only because it not piddling around my doorstep.
I just love fish storms.
Has anyone mentioned the convergent spinning off my SWFL coast?
I dont think it can do anything bad but it sure sparks my interest.


Just looks like our regular summertime showers. Hopefully we get some action soon. Here's a closeup for you.



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1581. ncstorm
lots of boomers..

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Quoting spathy:

Piddly only because it not piddling around my doorstep.
I just love fish storms.
Has anyone mentioned the convergent spinning off my SWFL coast?
I dont think it can do anything bad but it sure sparks my interest.
Yes i've mentioned it earlier but it probably won't be more than some good rains for someone.
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1579. OneDrop
Quoting sunlinepr:
Lots of boiling water around...

Is that huge swirl to the NE of the islands a gale center or just an ULL? Just curious if it might throw a swell toward the east coast of the US.
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Quoting aspectre:
13,000year-plus-old IceAge carving of a mammoth or mastodon found in Florida.


Good Artist
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Quoting Grothar:
Looking piddly.




will have too send EMILIA too the doc



i this send EMILIA the doc bill
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Quoting Grothar:


Don't feel bad. My kids make me do that, too!

Well..That's...different
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Quoting turtlehurricane:
Gotta love the parade of tropical cyclones in the eastern Pacific today. It's cool how you can see all the stages of a tropical cyclone's life at one time today in the below satellite photo alone. I made a little writeup about it on my blog http://weather.schematical.com/



Excellent work...
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1573. Grothar
Quoting Articuno:

i have to go to bed at 9 o clock at school nights, 10:30 in the summer time. :(


Don't feel bad. My kids make me do that, too!
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1572. Grothar
Quoting Some1Has2BtheRookie:



13,000 years old?

+ Mammoth or Mastodon?

+ Florida?

Hmmmmmmmmmm, I guess this explains Grothar's rug then. ;-) I guess he took it serious when they told him to write on the wall and they will read it later.


What do you think, blogging is new? We used to call it a "Wall Post", then some young kid created a webite and made billions. If I only knew.......!


98E has a tremendous moisture field.

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Quoting TropicalAnalystwx13:

It's 9 o clock.....

i have to go to bed at 9 o clock at school nights, 10:30 in the summer time. :(
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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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