July 2012: hottest month in U.S. history

By: Dr. Jeff Masters , 7:16 PM GMT on August 10, 2012

During the 1930s, a series of epic heat waves gripped the U.S., drying up the soil in an unprecedented drought that brought about the great Dust Bowl. The most intense heat hit during July 1936, which set a record for hottest month in U.S. history that stood for 76 years. That iconic record has now fallen, bested by 0.2°F during July 2012, which is now the hottest month in U.S. history, said NOAA's National Climatic Data Center (NCDC) this week. So far in 2012, we've had the warmest March on record, 3rd warmest April, 2nd warmest May, and warmest July. These remarkably warm months have helped push temperatures in the contiguous U.S. to the warmest on record for the year-to-date period of January - July, and for the 12-month period August 2011 - July 2012. Twenty-four states were record warm for that 12-month period, and an additional twenty states were top-ten warm. The past fourteen months have featured America's 2nd warmest summer (in 2011), 4th warmest winter, and warmest spring. The summer of 2012 is on pace to be a top-five warmest summer on record, and could beat the summer of 1936 as the warmest summer in U.S. history.


Figure 1. When the temperature peaked at an all-time high of 108° in Minneapolis, Minnesota on July 14, 1936, the want-ad staff at the 'St. Paul Daily News' was provided with 400 pounds of ice and two electric fans to cool the air in the press room. Photo from the Minnesota Historical Society.


Figure 2. Year-to-date temperature, by month, for 2012 (red), compared to the other 117 years on record for the contiguous U.S., with the five ultimately warmest years (orange) and five ultimately coolest years (blue) noted. The 2012 data are still preliminary. The year-to-date period of January - July was the warmest on record by a huge margin--1.0°F. Image credit: NOAA/NCDC.


Figure 3. For the fourth consecutive month, a new U.S. record for hottest 12-month period was set in July 2012. Five 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 - July 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 46% during the year-to-date January - July 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 seven months of 2012, and 74% 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 16th greatest since 1910. Extremes in 1-day heavy precipitation events were the 24th greatest in the 103-year record.


Figure 4. NOAA's U.S. Climate Extremes Index (CEI) for January - July shows that 2012 has had the most extreme first seven months of the year on record, with 46% of the contiguous U.S. experiencing top-10% extreme weather.

Little change to the U.S. drought during the past week
The great U.S. drought of 2012 remained about the same size and intensity over the past week, said NOAA in their weekly U.S. Drought Monitor report issued Thursday, August 9. The area of the contiguous U.S. covered by drought dropped slightly, from 63% to 62%, and the area covered by severe or greater drought stayed constant at 46%. The area of the country in the worst drought categories (extreme to exceptional drought) doubled from 10 percent last month to 22 percent this month. The extreme dryness and excessive heat devastated crops and livestock from the Great Plains to Midwest. During July, the area of the U.S. covered by moderate or greater drought was 57%, ranking as the 5th largest drought in U.S. history:

1) Jul 1934, 80%
2) Dec 1939, 60%
3) Jul 1954, 60%
4) Dec 1956, 58%
5) Jul 2012, 57%



Video 1. This is Not Cool: Peter Sinclair's July 2012 video from the Yale Forum on Climate Change and the Media couples historical footage with contemporary clips and news segments. In one of the latter, for instance, NBC anchor Brian Williams opens the network’s flagship news program with the words: “It’s now official. We are living in one of the worst droughts of the past 100 years.” NASA scientist James Hansen is featured testifying about risks of “extreme droughts” in the nation’s breadbasket, and I'm featured in a few clips talking about the drought of 2012.

I'll have a new post by noon Saturday.

Wunderground's weather historian Christopher C. Burt has a post looking back at the great Heat Wave of July 1936.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 1645 - 1595

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35Blog Index

Good morning everyone! To me it looks as though TD7 has degenerated into an open wave. HH haven't really found a center, and 850 mb vorticity shows an elongated structure which is indicative of an open wave and the LLC falling apart.

Member Since: Posts: Comments:
TD7 officially going to be reclassified as an open wave soon? Was beautiful as a wave about a week ago, many here commented that it was a great looking invest. Been sad and piddly since and not getting any healthier. Wonder if the NHC is second guessing ever upgrading it to TD7?
Member Since: December 31, 1969 Posts: Comments:
1643. sar2401
Quoting CANTBELIEVEIT:
as usual no one listened to me 4 days ago when i was saying that td13 would go south and fall apart and that 93l would go fish and fall apart check my post from 4 days ago 1023


Why do you think no one listened to you? Several of us have been saying something similar as well. So far, at least, WU isn't giving out gold stars for correct guesses. Now, the real trick is to be right on track and intensity when we get a major. That's a lot tougher than predicting lousy looking storms aren't going to do much.
Member Since: Posts: Comments:
Quoting FLASPOTTER:
Wow can't believe the ships model brings TD7 to a hurricane.


It's on roids. GFS is best after cyclonesis. NOGAPS is good at predicting Cyclonesis.
Member Since: Posts: Comments:
The blob is easily more powerful than the "TD7".


Stick a fork in it baby, it's done.

LOL.

...at least for now anyway. Probably take a day or two to reorganize, if it ever does at all.
Member Since: Posts: Comments:
Quoting CANTBELIEVEIT:
as usual no one listened to me 4 days ago when i was saying that td13 would go south and fall apart and that 93l would go fish and fall apart check my post from 4 days ago 1023


you mean... TD-07... I have been saying it also.
Member Since: Posts: Comments:
1638. sar2401
Quoting FLASPOTTER:
Wow can't believe the ships model brings TD7 to a hurricane.


That's why most of us don't believe the SHIPS model this year. :)
Member Since: Posts: Comments:


Open-wave???
Member Since: Posts: Comments:
1635. sar2401
Quoting lovemamatus:


www.messagetoeagle.com

Patrap posted it last night. It doesnt look good.


It's just an M1 X class flare. They happen at least several times a year, and should occur more frequently through 2013 as we approach a sunspot maxima. We ham radio operators look forward to these flares to give us some rare long distance communications on the upper frequency bands.
Member Since: Posts: Comments:
Wow can't believe the ships model brings TD7 to a hurricane.
Member Since: Posts: Comments:
1633. SLU
Lowest pressure 1011mb, the center has opened up. The RECON might as well call it a day and save the fuel for when the real action starts.

Member Since: Posts: Comments:
Quoting SouthDadeFish:
Not sure if this has been posted yet or not but....

TRMM recently made a nice pass, but TD 7 remains poorly organized. Here is the 37 GHz color, which shows little, if anything, in the way of banding:



And here is the 85 GHz Horizontal, which also shows a disorganized storm:



Not only is it disorganized, but there is very little convection. This disorganized pattern is being confirmed be recon.




Member Since: Posts: Comments:
1630. SLU
Quoting kmanislander:
Finding S and SE winds now where they previously found SW winds on the first pass down. Opening up.


Yep i realised that. Should be deactivated at 11am or the NHC might hold on to it for precautionary reasons until it clears the islands
Member Since: Posts: Comments:
Here is my diatribe for today:

Looking ahead a little bit, and with the exception of TD7 and back to watching the models again, I could not tell you when/when the next system will spin up. Need to remind folks that the rise to the "peak" period is just starting and we will get several more storms between now and October.

As far as the Cape Verde season is concerned (and 80% of all Atlantic hurricanes in any given season form from CV waves), it was off to an earlier start than usual this year but we have seen Ernesto (in the Caribbean) and TD7 fizzle and struggle. The better route to go, rather than hype or downcast this season, is to analize what just happened with both systems.

Essentially, conditions in the Central Atlantic have not been "perfect" for these two systems because most other factors being equal, the dry air over the Central Atlantic, and most importantly, the forward speed of both systems in the Central Atlantic and Eastern-Central Caribbean (average speed of over 20 mph for both systems) did not allow them to stack up a well defined lower level circulation in spite of favorable SST's and moderate wind sheer.

The real question then is; Was this just normal July-Early August climatology factors working against both systems which will get better going into the next several weeks, or, is this going to be the general pattern (dry air and excessive forward speed due to stronger than average trade winds) over the next several weeks?

Climatology says that conditions will become more favorable (in the Central Atlantic and Caribbean) over the next several weeks and with all of the other factors going into the favorable mode, we need to keep a close eye on dry air issues and whether the trade winds slow down.

Also, assuming that the CV season started early, it would not be unreasonable to assume that the "closer to home" period might start a little early too in the Western Caribbean, Gulf, and Eastern Seaboard from frontal remnants due to the Fall like trofs and fronts which have arrived early as well.

My point is, Mother Nature might be a little ahead of the normal schedule this year so we also have to keep a real close eye on the next arrival of the MJO in the Atlantic basin from West to East.
Member Since: Posts: Comments:
I'll be back for the 11 AM update but the recent download showing more S winds where they previously found SW. I think I have seen enough.
Member Since: Posts: Comments:
1627. Msdrown
Quoting MAweatherboy1:

We had an M class flare this morning... Not sure if it produced a CME.

\

I think Pat posted this pic last night... Nothing too unusual about it:



I agree, doesn't look bad but I'm going to leave and check it out. Be back later hopefully with some info. Before I go I'll try to find that informative post from early this morning and repost it.
Member Since: Posts: Comments:
1626. Grothar
Quoting lovemamatus:


The contention was that the gash had increased 1 million km since Wednesday in size, and could portend an "unprecedented event". Pretty scary stuff.

The Hurricane Hunters are not scheduled to fly into it.


LOL
Member Since: Posts: Comments:
1625. Msdrown
Quoting Tazmanian:



i dont find that photo vary funny in fac i call that mean too a cat plzs dont re post it


Not a big cat lover but have been around them a few times and the more playfull types are always getting themselves into these sits. Not sure how that is mean, not trying to anger you.
Member Since: Posts: Comments:
Not sure if this has been posted yet or not but....

TRMM recently made a nice pass, but TD 7 remains poorly organized. Here is the 37 GHz color, which shows little, if anything, in the way of banding:



And here is the 85 GHz Horizontal, which also shows a disorganized storm:



Not only is it disorganized, but there is very little convection. This disorganized pattern is being confirmed be recon.
Member Since: Posts: Comments:
Quoting Msdrown:



Same thing as usual. They are in a very siesmic area. They have at least one big one routinely but it is usually in remote areas not like this. Or you could get political and something went wrong with there nuke projects.


Don't worry, I won't get political. Just saying.
Member Since: Posts: Comments:
Finding S and SE winds now where they previously found SW winds on the first pass down. Opening up.
Member Since: Posts: Comments:
1621. hydrus
Quoting Drakoen:
TD 7 is only undergoing the initial onset of shear. Shear should worsen in magnitude as the models forecast for the upper level trough to sink southward even further. Assuming it can suvive that over the next 48 hours it may find better upper level conditions in the central or western Caribbean, but at the moment the eastern Caribbean looks very hostile.
Yes. This T.D has a good amount of spin to it. Should be interesting to watch. If it makes it to the west side, we will have something to watch. The CMC keeps 07 in the picture nearing or on the Yucatan Peninsula in 144 hours.
Member Since: Posts: Comments:
Quoting kmanislander:
Must be really nice weather out there for them to be flying around at 1100 feet LOL


Although not "low Level Flying" per se - it probably makes a nice change for them and IMHO they thoroughly deserve a "perk" now and again
Member Since: Posts: Comments:
Quoting lovemamatus:


www.messagetoeagle.com

Patrap posted it last night. It doesnt look good.


Alright, I checked the website.
1. That was from the 5th.
2. They used unprecedented NOT TRUE.
A. Quebec blackout
B. Carrington Event
3. I am very aware of the dangers of a CME impacting the Earth.
Member Since: Posts: Comments:
1617. Msdrown
Quoting Astrometeor:


Looked at the USGS page on that too. Wonder what's going on over there...



Same thing as usual. They are in a very siesmic area. They have at least one big one routinely but it is usually in remote areas not like this. Or you could get political and something went wrong with there nuke projects.
Member Since: Posts: Comments:
Quoting Drakoen:
TD 7 is only undergoing the initial onset of shear. Shear should worsen in magnitude as the models forecast for the upper level trough to sink southward even further. Assuming it can suvive that over the next 48 hours it may find better upper level conditions in the central or western Caribbean, but at the moment the eastern Caribbean looks very hostile.


20 knots max but all in all not too bad. TD7 is really struggling and so is the HH in trying to pin down a center.

Member Since: Posts: Comments:
looks like the HH is finding a open wave
Member Since: December 31, 1969 Posts: Comments:
1614. Msdrown
Quoting AussieStorm:

Hurricane Hunters search for TD-07



so more or less like this.....



At least the H/H and this little guy are working it hard you have to give them that. Again Too Funny.
Member Since: Posts: Comments:
Quoting AussieStorm:

Taz, I'm sure the cat is fine.



so ture
Member Since: December 31, 1969 Posts: Comments:
Quoting MAweatherboy1:

That might be Ernesto.


Yes, maybe. The CMC solution is broadly similar to the 00Z ECMWF ensemble and 00Z NOGAPS deterministic runs, although the latter two take it further NW and kill it in colder waters.
Member Since: Posts: Comments:
Quoting Tazmanian:



i dont find that photo vary funny in fac i call that mean too a cat plzs dont re post it

Taz, I'm sure the cat is fine.
Member Since: Posts: Comments:
Quoting Msdrown:


Not sure what you mean?? There have been reports lately about solar flares and CME's. Someone on here late last night was talking about this who seemed very knowledgable.

We had an M class flare this morning... Not sure if it produced a CME.

\

I think Pat posted this pic last night... Nothing too unusual about it:

Member Since: December 31, 1969 Posts: Comments:
Quoting barbadosjulie:


Morning Barbados246, I'm guessing we could start to see something about 11am. Not entirely sure what that something is though as there are all sorts of reports.

Trinidad is completely flooded out right now, its reported about 3" of rain so far. Vehicles under water etc


Hey Juliet it can be so confusing reading everyones thoughts and still not sure what will happen but i guess thats life and we just have to wait on mother nature to take her course. Its such a lovely day outside its hard to believe we are going to have a rain far less a TD.
Member Since: December 31, 1969 Posts: Comments:
Quoting GeorgiaStormz:
lol we had imposter on here and i didnt realize...

Who, What, Where, Why, When????
Member Since: Posts: Comments:
1607. Drakoen
TD 7 is only undergoing the initial onset of shear. Shear should worsen in magnitude as the models forecast for the upper level trough to sink southward even further. Assuming it can suvive that over the next 48 hours it may find better upper level conditions in the central or western Caribbean, but at the moment the eastern Caribbean looks very hostile.
Member Since: Posts: Comments:
Quoting AussieStorm:

Hurricane Hunters search for TD-07



so more or less like this.....




i dont find that photo vary funny in fac i call that mean too a cat plzs dont re post it
Member Since: December 31, 1969 Posts: Comments:
Quoting RTSplayer:



Ugh...

this thing needs to be backed up to an older version. It's horribly over-rating storms this year. It's off by like 10mb and 10mph or more...


I don't pay any attention to that anymore. Way off
Member Since: Posts: Comments:
Quoting MAweatherboy1:

That might be Ernesto.


Actually that is Ernesto. Or at least what's left of him.
Member Since: Posts: Comments:
Quoting MAweatherboy1:
T numbers are still running too high:


UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 11 AUG 2012 Time : 124500 UTC
Lat : 14:05:52 N Lon : 57:26:32 W


CI# /Pressure/ Vmax
3.4 / 999.5mb/ 53.0kt


Final T# Adj T# Raw T#
3.2 2.8 2.3



Ugh...

this thing needs to be backed up to an older version. It's horribly over-rating storms this year. It's off by like 10mb and 10mph or more...
Member Since: Posts: Comments:
img src="">

could this be the weak center echo?
Member Since: Posts: Comments:
lol we had imposter on here and i didnt realize...
Member Since: Posts: Comments:
Quoting Tazmanian:
well it looks like the 1st TD of the season too bust

Shhhhh don't say that. wunderkidcayman will get upset.

Just Joking dude. How is the beautiful Cayman Islands Today?
Member Since: Posts: Comments:
1599. hydrus
A long way out, but I thought this would be a interesting pattern if it were to evolve.
Member Since: Posts: Comments:
Quoting Msdrown:


Thats funny.


Looked at the USGS page on that too. Wonder what's going on over there...
Member Since: Posts: Comments:
1597. Msdrown
Quoting AussieStorm:


This is what I get from Cuba Radar


Yea, that proves my point, check the date upper left and the time upper right. This was yesterdays and I checked it periodically through the day and it never changed.
Member Since: Posts: Comments:
Must be really nice weather out there for them to be flying around at 1100 feet LOL
Member Since: Posts: Comments:

Viewing: 1645 - 1595

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35Blog Index

Top of Page

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather