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


More coming up the coast so get ready!
Member Since: October 26, 2011 Posts: 0 Comments: 2651
Quoting StormTracker2K:


Finally a normal "Summertime Pattern" across the Southern US something we haven't seen in many years now.


Tropical rains over TX now
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Quoting StormTracker2K:


Finally a normal "Summertime Pattern" across the Southern US something we haven't seen in many years now.


yes occasionally but not the constant kind like this
Member Since: June 17, 2011 Posts: 11 Comments: 6468
Quoting washingtonian115:
Oh geez it's regular thunderstorms in Florida.Ohhh the horror.Everyone is gonna die.....


LOL!
Member Since: October 26, 2011 Posts: 0 Comments: 2651
Quoting weatherh98:


youre right, its still a LOT closer though

Interesting from your scetch, map, that the Arctic ocean was almost a landlocked inland sea during the ice age!
This probably contributed to the lenth of the ice age as not even currents passed through the area. Now with more water and warmer at higher sea levels rapid heating must be in order.
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over 7000 lightning strikes with the line of storms that came through here, looks like FL. summertime pattern is back!
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Quoting RitaEvac:
Extreme weather: Get ready to see more of it, scientists say

People at the bottom of page on CNN are acting crazy, folks fighting about it's not real, it's real, yada, yada, yada.


i would click on the link... if it werent cnn...
Member Since: June 17, 2011 Posts: 11 Comments: 6468
Quoting weatherh98:

blobs blobs everywhere


Finally a normal "Summertime Pattern" across the Southern US something we haven't seen in many years now.
Member Since: October 26, 2011 Posts: 0 Comments: 2651
Quoting weatherbro:


Actually back then the westerlies were screemin' year round with fronts drying out the Peninsula even through the dog days of Summer(that term is a misnomer)! So even if they could collide, forget about the rain as prehistoric Florida was a steppe Climate.:) Even the Yucatan Peninsula saw their seabreeze t-storms obliterated! I bet what would be Walt Disney World was covered in snow 1/4th of the year!!!
I was just wondering what the tropical wx season might have been like back then... lol
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Extreme weather: Get ready to see more of it, scientists say

People at the bottom of page on CNN are acting crazy, folks fighting about it's not real, it's real, yada, yada, yada.
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Oh geez it's regular thunderstorms in Florida.Ohhh the horror.Everyone is gonna die.....
Member Since: August 14, 2010 Posts: 10 Comments: 16756
No end in sight in Fort Myers. Expect 5" to 7" of rain out of this mess. We had 7" of rain yesterday over lake Apopka to my west so it may happen again today but this time across SW FL.

Member Since: October 26, 2011 Posts: 0 Comments: 2651
1359. hydrus
Quoting weatherh98:
florida during ice age


then you would have the "neverglades"
Yep, and just a short trip across the Yucatan Channel..I bet commerce was well established for the folks back then..:)
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Quoting ncstorm:


If someone is having a bad day then dont take it out on the blog..stop making excuses for him and as he said so eloquent yesterday to someone, he dosent like people speaking for him..you may just catch it yourself sport..

but seriously, Baha, I am going to start calling you the Peacekeeper..your heart is in the right place
See, unlike youse guys, I just don't sweat it. I learned early on that the [-] key can be the key to serenity on this blog.

I'm not making excuses for Pat; "having a bad day" is an OBSERVATION. I been [-]ing him all day, not making excuses for his comments. And I appreciate icmoore's comments, which I think finally got his attention. Some days it's better just to get off the blog before you get put off. I'm glad he took a break.

As for "catching it myself", I can give as good as I get just about anytime... I just rarely find it appropriate to do so here. And too much wasted effort.

I thought we had some good discussion about GW impacts and what pple should be doing about them; that was the good of the blog today. I wasn't going to let somebody else's unhappiness ruin my day off.

YMMV
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Quoting StormTracker2K:

blobs blobs everywhere
Member Since: June 17, 2011 Posts: 11 Comments: 6468
Quoting StormTracker2K:


More "blobology". That blob southeast of Texas sure did dump on us. ;)
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This is a pic of that strong storm that passed thru here an hour ago..

Member Since: October 26, 2011 Posts: 0 Comments: 2651
Member Since: October 26, 2011 Posts: 0 Comments: 2651
This looks like a pattern to where thunderstorms are going to build even after sunset here across E C FL as there are thunderstorms building in from the south and some out in the Atlantic which may come ashore later this evening.


Member Since: October 26, 2011 Posts: 0 Comments: 2651
Quoting ClimateChange:
I actually believe 1 in 1.6 million is a reasonable estimate. I keep reading that the monthly temperature is not truly random -- most of this, I see coming from usual suspects who try to minimize every weather event to hide the effects of climate change. However, I'd like to see more evidence of the correlation before I can agree with that assertion. It's not as obvious a proposition as they make it seem. I agree that on a month-to-month basis, there's probably some correlation. However, Lucia found an "autocorrelation" coefficient of only 0.163 for U.S. data, which isn't much greater than chance. The corresponding value for the global series was much greater, 0.935. Using the 0.163 correlation, even she found odds of around 1 in 500,000 -- much lower than her original estimate, which incorrectly presumed the global correlation would apply to US figures. However, I'm trying to ascertain whether this correlation is truly valid.

Yes, I agree on a month-to-month basis, there is some correlation in U.S. temperature. A warm month is more likely to be followed by a warm month than otherwise. However, I don't know if this accurately considers the variability in the climate signal to changes in external drivers, such as ENSO and the other oceanic oscillations. On a month-to-month basis, these would likely be minimal. However, on a 13 month period, these would be substantial. The state of these various drivers can change substantially over that period of time. So I'm curious as to whether Lucia's model considers correlation only on a month-to-month basis, or if it also considers the correlation between a value 13 months ago and a current value, a value 12 months ago and a current value, and so on. I wouldn't be surprised if the correlation in those cases is actually negative -- that is, less than random chance would indicate.


Link
Member Since: June 17, 2011 Posts: 11 Comments: 6468
I actually believe 1 in 1.6 million is a reasonable estimate. I keep reading that the monthly temperature is not truly random -- most of this, I see coming from usual suspects who try to minimize every weather event to hide the effects of climate change. However, I'd like to see more evidence of the correlation before I can agree with that assertion. It's not as obvious a proposition as they make it seem. I agree that on a month-to-month basis, there's probably some correlation. However, Lucia found an "autocorrelation" coefficient of only 0.163 for U.S. data, which isn't much greater than chance. The corresponding value for the global series was much greater, 0.935. Using the 0.163 correlation, even she found odds of around 1 in 500,000 -- much lower than her original estimate, which incorrectly presumed the global correlation would apply to US figures. However, I'm trying to ascertain whether this correlation is truly valid.

Yes, I agree on a month-to-month basis, there is some correlation in U.S. temperature. A warm month is more likely to be followed by a warm month than otherwise. However, I don't know if this accurately considers the variability in the climate signal to changes in external drivers, such as ENSO and the other oceanic oscillations. On a month-to-month basis, these would likely be minimal. However, on a 13 month period, these would be substantial. The state of these various drivers can change substantially over that period of time. So I'm curious as to whether Lucia's model considers correlation only on a month-to-month basis, or if it also considers the correlation between a value 13 months ago and a current value, a value 12 months ago and a current value, and so on. I wouldn't be surprised if the correlation in those cases is actually negative -- that is, less than random chance would indicate. If the correlation is actually negative, then the true probability might be even lower than 1 in 1.6 million.
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Quoting MAweatherboy1:
Exactly the wording I would've used...

A RATHER SMALL AMORPHOUS BLOB IS ALL THAT REMAINS OF THE DEEP
CONVECTION ASSOCIATED WITH DANIEL.

Looks like the surface circulation is likely to last until tomorrow, though.

See... blob can too, be meteorological... lol

Quoting LargoFl:
I hope GT isnt involved in this over in Tampa.........................The afternoon heat and sea breeze are helping to produce another round of heavy showers and thunderstorms.
Officials with Tampa Electric said nearly 5,000 customers are without power. Check to see if your area is affected.

In Hillsborough County, officials said there are "widespread" reports of downed tree limbs and power lines in the area of east Adamo Drive. A power pole has been reported down at Palm River and Falkenburg Road.

Fire officials said they have also received reports of a tree that has fallen on a house on 10th Street in Tampa.

The storms are moving WNW at 10 miles an hour. Storms may contain heavy rain, frequent lightning, and small hail.
Although parts of the Bay area didn't get rain yesterday, many did, as thunderstorms moved along and in from the Gulf of Mexico.

Some areas, including Town & Country and areas north, took on more than two inches of rain.
Uh... when is the RNC supposed to be meeting in Tampa again?

Quoting weatherh98:


I make my mom do it:)
[Darkly] I am very glad I am not your mom.
Member Since: October 25, 2005 Posts: 19 Comments: 21883
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The westside of FL is getting rocked right now. Also of note is that thunderstorms are forming near West Palm beach and moving NW almost merging with this active on the westside of FL.

Member Since: October 26, 2011 Posts: 0 Comments: 2651
Up to 3.07" in exactly one hour. Still pouring..
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Quoting BaltimoreBrian:
A few years ago I read about a computer simulation of Florida's climate during the ice ages. According to the simulations when sea level was more than 200 feet below today's level the Florida peninsula became too wide for sea breezes to collide. That took out about 20% of warm season rainfall in the peninsula.


Actually back then the westerlies were screemin' year round with fronts drying out the Peninsula even through the dog days of Summer(that term is a misnomer)! So even if they could collide, forget about the rain as prehistoric Florida was a steppe Climate.:) Even the Yucatan Peninsula saw their seabreeze t-storms obliterated! I bet what would be Walt Disney World was covered in snow 1/4th of the year!!!
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1345. ncstorm
Quoting BahaHurican:
Blue holes here suggest that the Great and Little Bahama Banks were likely large islands during the last ice age.

I said earlier, Pat is having a bad day... I know some expect those around them to be perfect all the time... we aren't being realistic when we do that. OTOH, having a bad day is not an excuse to take it out on others. And there's nothing wrong in calling somebody on excessive snarkiness, even if they've been around for a long time, the way some of us have. The minus key works for everybody, and is appropriate for just about everybody once or twice...

YMMV


If someone is having a bad day then dont take it out on the blog..stop making excuses for him and as he said so eloquent yesterday to someone, he dosent like people speaking for him..you may just catch it yourself sport..

but seriously, Baha, I am going to start calling you the Peacekeeper..your heart is in the right place
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Quoting BahaHurican:
Dunno about that... the channels between the Bahamas, FL and Cuba are fairly deep.


youre right, its still a LOT closer though
Member Since: June 17, 2011 Posts: 11 Comments: 6468
We've now had 2.47" of rain in 55 minutes.. And it is still pouring. I'm not understanding how this storm is still going temp outside is 71 degrees...
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Quoting MAweatherboy1:

Actually, it may be starting one... This kind of looks like concentric eyewalls...

b Would explain the pinhole eye too.
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Quoting weatherh98:


im not sure, you realize the cuban missile crisis if this were an ice age? we would be connected.

this is all theoretical, chaos theory would have changed things
Dunno about that... the channels between the Bahamas, FL and Cuba are fairly deep.
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Truth be told, I've only gotten a little bit of rain today and I'm right next to the seabreeze collision. A lot of lightning in the distance, and possibly another storm coming towards our area now.
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Quoting MAweatherboy1:

I think Jose is...



I agree. Jose was a BEAST!
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Quoting Pirate999:


I think you can call it "Armageddon" or "you are all going to die" storms and many will still not pay attention, much less get out of the way.


if i hear cat 4 imma thibk dangerous. then think, should i stay or go, i it weakens right before landfall...

when i hear super storm i think holy crud see you later.
Member Since: June 17, 2011 Posts: 11 Comments: 6468
Quoting weatherh98:


they know for a fact that that was the case. in under water caves on the southern coast, they found bat dung and Saharan dust
Blue holes here suggest that the Great and Little Bahama Banks were likely large islands during the last ice age.

Quoting icmoore:


I can appreciate that and as you can see I have been a member for a long time and I have appreciated his info and even plussed him many times however I have witnessed his harsh behaviour on many occasions, most would not qualify as sarcastic. Back to the weather now..lights have flickered and storms are popping up all around so I'll be looking at radars now.
I said earlier, Pat is having a bad day... I know some expect those around them to be perfect all the time... we aren't being realistic when we do that. OTOH, having a bad day is not an excuse to take it out on others. And there's nothing wrong in calling somebody on excessive snarkiness, even if they've been around for a long time, the way some of us have. The minus key works for everybody, and is appropriate for just about everybody once or twice...

YMMV
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Ok I take it back, now it's lighting like crazy, pouring down rain, and it's windy.... 2.11" so far today...
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Quoting RitaEvac:
From hear on out on this blog when a storm hits 150mph, calling it Super Storm. A storm at 140mph....we'll start saying "we are nearing Super Storm now" how much you wanna bet it would catch on with TWC and media outlets and a new era of Super Storm would be born in the Atlantic.


Yes lets be trend setters! super storm at 150...

for example

Hurricane emilia almost became a super storm before weakening
Member Since: June 17, 2011 Posts: 11 Comments: 6468
Quoting BahaHurican:
Some pple around here [not pointing any fingers] would have to clean up their rooms first.


I make my mom do it:)
Member Since: June 17, 2011 Posts: 11 Comments: 6468
From here on out on this blog when a storm hits 150mph, calling it Super Storm. A storm at 140mph....we'll start saying "we are nearing Super Storm now" how much you wanna bet it would catch on with TWC and media outlets and a new era of Super Storm would be born in the Atlantic.
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Quoting icmoore:


Hmmm wow...born in FL and lived here my entire almost 57 years ... wouldn't live anywhere else either. Don't take too kindly to your name calling...grown ups should play by the rules, too.
Just a bunch of Hater wishing they lived in the second best state in USA :)..... Hawaii is 1st lol
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Quoting RitaEvac:
Lets break it down like this:

If you hear on the news it's a powerful cat 4 but not a cat 5.....or you hear it's a Super Storm (150mph) I think the latter part will catch your attention more so especially in America.


I think you can call it "Armageddon" or "you are all going to die" storms and many will still not pay attention, much less get out of the way.
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DANIEL WEAKENS A LITTLE MORE...
------------------------------------------------- -------------------------------

2:00 PM PDT Tue Jul 10
Location: 15.3°N 136.6°W
Moving: W at 17 mph
Min pressure: 1000 mb
Max sustained: 50 mph
Daniel is taking his clothes off and becoming a naked swirl.


EMILIA SLOWLY WEAKENING BUT STILL A MAJOR HURRICANE...
------------------------------------------------- -------------------------------

2:00 PM PDT Tue Jul 10
Location: 13.9°N 114.5°W
Moving: WNW at 9 mph
Min pressure: 953 mb
Max sustained: 125 mph
She has a better eye even though she is getting older.

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Quoting RitaEvac:


155mph wind might as well be cat 5. 156-155, makes no difference in light of things. I actually like the W PAC system, call 150mph storms Super Storms. Don't matter if it's cat 5, once it hits 150mph, it's Super in one way or another


yes but 154 would mean that any storm of 155 would be cat 5 as pposed to the 160

yes 150 would be a good mark to put in super
Member Since: June 17, 2011 Posts: 11 Comments: 6468
AND "our recent power outage was brought to you by our proud sponsor, Lightning. Putting people in the dark since the dawn of time."

Anyways, a little humor there. Now the heavy rain has stopped and we've gone all flash, bang everywhere...
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The left kinked line shows Daniel's path for its 72hours as a Hurricane

The right connected line-segments shows Emilia's path as a Hurricane, 36hours thus far.

Looks like Emily is about to make a run in Daniel's trough, if it hasn't been doing so already.
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Quoting SteveDa1:
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??
Some pple around here [not pointing any fingers] would have to clean up their rooms first.
Member Since: October 25, 2005 Posts: 19 Comments: 21883
Lets break it down like this:

If you hear on the news it's a powerful cat 4 but not a cat 5.....or you hear it's a Super Storm (150mph) I think the latter part will catch your attention more so especially in America.
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South of Houston we were gettng about 1 - 1.5" of rain an hour. Stream and street flooding over the past few hours. Still raining but not as hard. Combined with the rain yesterday and early this morning we have had quite a bit of water. My "official" gauge is my pool. When it overflows I know we've been dumped on; it's way overflowed. I'll take it though.
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Quoting MAweatherboy1:

I think Jose is...


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Quoting weatherh98:


i agree. more cat 5s.


155mph wind might as well be cat 5. 156-155, makes no difference in light of things. I actually like the W PAC system, call 150mph storms Super Storms. Don't matter if it's cat 5, once it hits 150mph, it's Super in one way or another
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1321. LargoFl
....................think i'll shut the puter down, way too much lightning and the lights are blinking..stay safe out there, see ya later
Member Since: August 6, 2011 Posts: 4 Comments: 37950

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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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