Extreme storms and extreme heat hit the U.S.

By: Dr. Jeff Masters , 5:50 PM GMT on June 30, 2012

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A violent line of organized severe thunderstorms called a derecho swept across the U.S. from Illinois to Virginia on Friday, damaging houses, toppling trees, bringing down power lines. The storms killed six people in Virginia, two in New Jersey, and one in Maryland, and left at least 3.4 million people without power. The thunderstorms in a derecho (from the Spanish phrase for "straight ahead") create violent winds that blow in a straight line. The traditional definition of a derecho is a thunderstorm complex that produces a damaging wind swath of at least 240 miles (about 400 km), featuring a concentrated area of thunderstorm wind gusts exceeding 58 mph (93 km/hr.) A warm weather phenomenon, derechos occur mostly in summer, especially June and July in the Northern Hemisphere. They can occur at any time of the year and occur as frequently at night as in the daylight hours. As seen on our wundermap with the "go back in time" feature turned on, Friday's derecho began near Chicago in the early afternoon, then marched east-southeast, peaking in intensity over Virginia and Washington D.C. on Friday evening. The derecho was unusually intense due to the extreme heat, which helped create an unstable atmosphere with plenty of energy to fuel severe thunderstorms.


Figure 1. Radar image from our wundermap with the "go back in time" feature turned on for 11 pm EDT Friday June 29, 2012, showing the derecho over Washington D.C. and Baltimore. Click on the "hour" button above the wundermap to advance the time by one hour to watch the progress of the derecho across the country.


Figure 2. NOAA's Storm Prediction Center (SPC) logged 871 reports of damaging winds on Friday. Twenty one of these reports were for winds over 80 mph. The highest wind gust was in Oswego, Illinois: 92 mph.



Figure 3. A dramatic change in the weather in Buckeye land: the temperature at Ohio State University in Columbus, Ohio dropped from 97°F to 68° after passage of Friday's derecho. The storm brought a wind gust of 82 mph to campus, and 0.86" of rain.

Historic heat wave topples Dust Bowl-era extreme heat records
A historic heat wave on a scale and intensity not seen in the U.S. since the great heat waves of the 1930s Dust Bowl era set new all-time heat records for at least ten major cities Friday. According to wunderground's weather historian Christopher C. Burt, fifteen of the 303 major cities he maintains records for on the wunderground extremes page have set all-time heat records in the past four days. The only year with more all-time heat records is 1936, when 61 cities set all-time heat records. In 2011, which had the 2nd warmest summer in U.S. history, only ten of the 303 cities set all-time heat records during the entire summer. With the the hottest month of the year (July) still to come, 2012 threatens to rival the great Dust Bowl summer of 1936 for extreme heat.

All-time records for any date tied or broken on Friday:

109° Nashville, TN (old record 107° 7/28/1952
109° Columbia, SC (old record 107° on two previous occasions)
109° Cairo, IL (old record 106° on 8/9/1930)
108° Paducah, KY (ties same on 7/17/1942
106° Chattanooga, TN (ties same on 7/28/1952)
105° Raleigh, NC (ties same on 8/21/2007 and 8/18/1988)
105° Greenville, SC (old record 104° 8/10/2007 although 106° was recorded by the Signal Service in July 1887)
104° Charlotte, NC (ties same on 8/9 and 10/2007 and 9/6/1954)
102° Bristol, TN (ties same on 7/28/1952-this site now known as `Tri-State Airport')
109° Athens, GA. This is just 1° shy of the Georgia state record for June of 110° set at Warrenton in 1959.

All-time state June heat records set Friday:

113° Smyrna, TN (old record 110° in Etowah in June 1936)
109° Cairo, IL (old record 108° in Palestine in June 1954)

Also of note: Atlanta, GA hit 104° (its all-time June record), and just 1° shy of its all-time record of 105° set on 7/17/1980. The forecast for Atlanta on Saturday calls for a high of 105°F, which would tie for the hottest day in the city's history.

Wunderground's weather historian Christopher C. Burt has a new post called The Amazing June Heat Wave of 2012 Part 1: The West and Plains June 23 - 27 summarizing the early portion of this week's historic heat wave. He plans to make a follow-up post on Sunday summarizing the records set on Friday and Saturday.

Relatively quiet in the Atlantic
An area of heavy thunderstorms, associated with an upper level low pressure system, has developed in the Gulf of Mexico along the Texas coast. This disturbance will probably move ashore over Texas before development into a tropical depression can occur, and NHC is giving it a 0% chance of development. The tropical wave approaching the Lesser Antilles (Invest 97L) has dissipated due to dry air, and is no longer a threat. None of the reliable computer models are developing anything during the next seven days.

Jeff Masters

Chicago Shelf (LarrySmit)
Chicago Shelf
Summer Heat (gardner48197)
Summer Heat
Smokey Clouds (LarrySmit)
Asperatus Clouds
Smokey Clouds
And the Sky Opened Up! (webgal)
Much needed thunderstorms came through west-central Illinois late this evening. The lightning was absolutely incredible!
And the Sky Opened Up!

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the MJO is now in phase 2. Development shouldn't happen for a few weeks now...
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Here's the derecho as it began in Chicago, and then as it crossed through Indiana.


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Quoting STXHurricanes2012:
So no cares about the near 13 inches near falcon dam....it caused the main highway to close due to high water!!!


pics orit didnt happen bro
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They said they didn't know where the wave was at 8 p.m. so that may be it showing some convection at 11:30. Anyhow, everything is more understandable in the morning. By the way my friend in Washington DC suburb says she's been without power for 24 hrs.
Is this because of the derecho?
Member Since: July 11, 2006 Posts: 14 Comments: 11358
Quoting Levi32:
Python is officially the coolest thing in the world. There are so many possibilities for making customized graphics now.

Current 500mb:



LOL @ all the ridging. This is brutal...
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@ Chicklet... see what u mean... think the wave they were drawing in at 36W somehow got retarded?
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Quoting BahaHurican:
It was added on the map... I thought I saw something there. Prolly read wrong...


This is the 8 p.m. Discussion which doesn't include any "PRECIPITABLE" water vapor imagery between 30 and 35W:

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 19N22W TO 11N23W MOVING W NEAR 10-15 KT.
UPPER AIR TIME SECTION DATA FROM DAKAR SENEGAL INDICATES THAT THE WAVE MOVED OFF THE COAST OF AFRICA BETWEEN 28/1200 UTC AND 29/0000 UTC. TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT THE WAVE LIES WITHIN A LARGE SURGE OF DEEP LAYER MOISTURE. THERE IS ALSO A BROAD CLEARING WITHIN THE SAHARAN AIR LAYER. SCATTERED MODERATE CONVECTION IS S OF THE WAVE FROM 6N-9N BETWEEN 19W-26W.

LOW-AMPLITUDE TROPICAL WAVE IS ALONG 12N36W TO 8N37W MOVING W NEAR 10-15 KT. THE WAVE WAS ADDED DUE TO A TRACKABLE AREA OF CONVECTION THAT COULD BE TRACED BACK TO THE COAST OF AFRICA.
HOWEVER...THE EXACT LOCATION OF THE WAVE IS DIFFICULT TO DISCERN DUE TO ITS LOW-AMPLITUDE. SCATTERED MODERATE CONVECTION IS FROM 8N-10N BETWEEN 35W-39W.

TROPICAL WAVE IS ALONG 19N58W TO 11N57W MOVING W NEAR 15-20 KT.
THE WAVE COINCIDES WITH A SURGE IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. VISIBLE SATELLITE IMAGERY SHOWS BROAD LOW-LEVEL CYCLONIC FLOW NEAR THE WAVE AXIS WHICH IS CONFIRMED BY AN OSCAT SCATTEROMETER PASS. SCATTERED MODERATE CONVECTION IS E OF THE WAVE AXIS FROM 10N-15N BETWEEN 54W-58W
Member Since: July 11, 2006 Posts: 14 Comments: 11358
Quoting Patrap:
At least 13 deaths blamed on eastern U.S. storms

Updated 9:52 PM ET

(CBS/AP) WASHINGTON - .

In West Virginia, 232 Amtrak passengers were stranded Friday night on a train that was blocked on both sides by trees that fell on the tracks, spending about 20 hours at a rural station before buses picked them up.
Whoa... I've ridden that train... it's a great ride when the weather's great, but wouldn't want to be stuck on the New River in that situation... that sounds like numerous multiple trees...
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east carb wave stringing out some convection
Member Since: July 15, 2006 Posts: 174 Comments: 54616
Too cool to not share :)

http://www.examiner.com/video/ring-of-fire-derech o-radar-loop

Wow!
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Python is officially the coolest thing in the world. There are so many possibilities for making customized graphics now.

Current 500mb:

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Quoting Chicklit:


I don't see anything about this in the 8 p.m. Discussion.
It was added on the map... I thought I saw something there. Prolly read wrong...
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At least 13 deaths blamed on eastern U.S. storms

Updated 9:52 PM ET

(CBS/AP) WASHINGTON - Millions across the mid-Atlantic region sweltered Saturday in the aftermath of violent storms that pummeled the eastern U.S. with high winds and downed trees, killing at least 13 people and leaving 3 million without power during a heat wave.

Power officials said the outages wouldn't be repaired for several days to a week, likening the damage to a serious hurricane. Emergencies were declared in Maryland, West Virginia, Ohio, the District of Columbia and Virginia, where Gov. Bob McDonnell said the state had its largest non-hurricane outage in history, as more storms threatened. "This is a very dangerous situation," the governor said.

In West Virginia, 232 Amtrak passengers were stranded Friday night on a train that was blocked on both sides by trees that fell on the tracks, spending about 20 hours at a rural station before buses picked them up. And in Illinois, storm damage forced the transfer of dozens of maximum-security, mentally ill prisoners from one prison to another.

In some Virginia suburbs of Washington, emergency 911 call centers were out of service; residents were told to call local police and fire departments. Huge trees fell across streets in Washington, leaving cars crunched up next to them, and onto the fairway at the AT&T National golf tournament in Maryland. Cell phone and Internet service was spotty, gas stations shut down and residents were urged to conserve water until sewage plants returned to power.

The outages were especially dangerous because they left the region without air conditioning in an oppressive heat. Temperatures soared to highs in the mid-90s in Baltimore and Washington, where it had hit 104 on Friday.

"I've called everybody except for the state police to try to get power going," said Karen Fryer, resident services director at two assisted living facilities in Washington. The facilities had generator power, but needed to go out for portable air conditioning units, and Fryer worried about a few of her 100 residents who needed backup power for portable oxygen.

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I know Baha, been lurking for a long time, over two years, just saying; thanks.
Member Since: April 18, 2012 Posts: 0 Comments: 2437
its july now
ice will melt
at a rapid rate
till mid september

Member Since: July 15, 2006 Posts: 174 Comments: 54616


I don't see anything about this in the 8 p.m. Discussion.


Member Since: July 11, 2006 Posts: 14 Comments: 11358
Quoting Tribucanes:
WU is great, I come here for the before the storm: when, how fast, likelihood, and most importantly, the why. I guess the name says it all, but I'm shocked there's not more bloggers here. I luckily stumbled on this site. Thanks everyone who contributes their time, knowledge, and to the wishcasters; prognosticate on!
R u kidding? There's been nobody here this week but a few FL bloggers... Wait until August, when the season has really got going, and u get the Caribbean / Central American / Mexican / GoM / FL / NC / rest of the world bloggers on here... not to mention Orca and and the west coast gawkers... it can get really crowded in here... talking 100 posts in less than 10 minutes, IIRC from Irene last year....
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436. JLPR2
Quoting Tropicsweatherpr:
JLPR2,hopefully July is not as extreme as June was. Here is the June report from the San Juan NWS.

Link


I'm crossing my fingers and hoping lots of TW make their way to us to compensate for the rain that didn't fell on June.
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Member Since: July 15, 2006 Posts: 174 Comments: 54616
JLPR2,hopefully July is not as extreme as June was. Here is the June report from the San Juan NWS.

Link
Member Since: April 29, 2009 Posts: 75 Comments: 14406
Ya Goosegirl, almost four million without power during this heat wave was a really bad coincidence. I hope the Golden Rule applies and people are looking out for those in need without power for what could be days. Authorities doing great, opening extra cooling centers everywhere that was hit by this historic wind event. If this heat wave and drought doesn't subside in the next handful of weeks it's going to get extremely serious, as the good people of Colorado God bless their souls, know all too well.
Member Since: April 18, 2012 Posts: 0 Comments: 2437
Quoting JLPR2:
What's left of 97L has reached the Lesser Antilles.



That is good news for some of those islands that need the rain badly. Let's see how much rain falls in PR.
Member Since: April 29, 2009 Posts: 75 Comments: 14406
Quoting RTSplayer:


Has that been confirmed by human observers?

I didn't trust the radar estimates because in the past the radar nearly doubles it's estimates of extreme precipitation events.

Corpus Radar says over a foot, and Brownsville radar says over 10 inches in that area, but what does an actual rain gauge say?

well in the report when they had the flash flood warning they reported 9 inches that was three hrs ago...dont know much since
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Hey, I'm back! We got lucky and lost power for about 24 hours, I hear some folks may wait for another week. The entire state of WV has been declared a federal disaster area. The winds were intense, upwards of 80-90 mph and the entire line blasted thru at 100 miles per hour. I worried about those of you further east, but got knocked off line early in the storm. Washingtonian, glad to hear you and yours are safe. I will continue to serve as your weather scout and to get word out if the storms fire up again. Stay safe and cool!
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429. etxwx
Quoting Dakster:


If you watch the tests, that stuff is really strong. I saw some installed on a house down here and it definitely looks easier to install than plywood, but not as easy as accordion shutters. What is the cost difference? or have you not looked at getting those installed.

I cheated and got impact doors and windows. Although I still have some conventional windows left to do.


I'm mainly interested in it for protecting a fairly new - and large - sliding glass door. We have a log house so attaching shutters might be a bit tricky. There are no local dealers so I can't check the fabric out in person. I appreciate the feedback. Thanks Dakster!
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Bad, bad ridge, LOL. That is not a good setup...
Quoting KEEPEROFTHEGATE:





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WU is great, I come here for the before the storm: when, how fast, likelihood, and most importantly, the why. I guess the name says it all, but I'm shocked there's not more bloggers here. I luckily stumbled on this site. Thanks everyone who contributes their time, knowledge, and to the wishcasters; prognosticate on!
Member Since: April 18, 2012 Posts: 0 Comments: 2437




Member Since: July 15, 2006 Posts: 174 Comments: 54616
425. JLPR2
What's left of 97L has reached the Lesser Antilles.

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Quoting Dakster:


I care... But what can I say?

It sucks, you can't do anything about it. Hope no one get killed or flooded out of their homes.

Hope the Dam holds and doesn't break, as that would be really bad.


Hermine Sept '10 dumped 15" in 8 hours on us, but centex is built for floods by... flooding. I don't doubt the 13" at Falcon Lake. Blob gave us incredible moisture in Austin which we just shunted straight up and let the upper atmosphere dissipate it like it never happened.
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Quoting STXHurricanes2012:
So no cares about the near 13 inches near falcon dam....it caused the main highway to close due to high water!!!


Has that been confirmed by human observers?

I didn't trust the radar estimates because in the past the radar nearly doubles it's estimates of extreme precipitation events.

Corpus Radar says over a foot, and Brownsville radar says over 10 inches in that area, but what does an actual rain gauge say?
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Quoting etxwx:
Since it's kinda slow, I have a question. Has anyone had experience with the new hurricane fabric panels? (such as Astroguard from Home Depot) We're far enough inland we don't need extreme window protection, and we're getting kinda old to heft plywood around. Just curious if it's easy to install and seems sturdy enough. Thanks.


If you watch the tests, that stuff is really strong. I saw some installed on a house down here and it definitely looks easier to install than plywood, but not as easy as accordion shutters. What is the cost difference? or have you not looked at getting those installed.

I cheated and got impact doors and windows. Although I still have some conventional windows left to do.
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If it fails our terrorist enemies will have to pick a different target.

See Below:

As reported in OutRageToday.com, a recent drug cartel plot to blow up the Falcon Dam on the Rio Grand was narrowly averted recently, and could have affected 4 million US Citizens, agriculture and commerce. It is thought to resemble a strategy consistent with those of the Iranian backed Hezbollah.
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Quoting MAweatherboy1:

I doubt it... The start of the month was actually quite cool for many... I believe we're finishing at or slightly below average here in the Northeast... Still a hot month compared to average for a lot of the country, but probably nothing historic.


Yeah, this won't be a record warm June overall, but it's still very warm. I read earlier this month that there had been 12 straight months in the top third percentile of warmth. I suspect that trend will continue this month.
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Quoting STXHurricanes2012:
So no cares about the near 13 inches near falcon dam....it caused the main highway to close due to high water!!!


I care... But what can I say?

It sucks, you can't do anything about it. Hope no one get killed or flooded out of their homes.

Hope the Dam holds and doesn't break, as that would be really bad.

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418. etxwx
Since it's kinda slow, I have a question. Has anyone had experience with the new hurricane fabric panels? (such as Astroguard from Home Depot) We're far enough inland we don't need extreme window protection, and we're getting kinda old to heft plywood around. Just curious if it's easy to install and seems sturdy enough. Thanks.
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Caribbean Storm Update June 26th English & Espa�ol

Video Update


Blog Update


Video Update

Link


Link
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Quoting STXHurricanes2012:
Link
No one saw this coming! Thank you blob lol
So what were mets calling our blob - a disturbance in the GOM? I planned moving my sister's heavy furniture during the cloud cover, never got to hear any wx discussion of it.

Blob did drop temps to comfortable, after last Tuesday's 110 and ~100s since.
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Quoting MAweatherboy1:

I doubt it... The start of the month was actually quite cool for many... I believe we're finishing at or slightly below average here in the Northeast... Still a hot month compared to average for a lot of the country, but probably nothing historic.


Yeah, this won't be a record warm June overall, but it's still very warm. I read earlier this month that there had been 12 straight months in the top third percentile of warmth. I suspect that trend will continue this month.
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So no cares about the near 13 inches near falcon dam....it caused the main highway to close due to high water!!!
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Quoting BahaHurican:
I hate to mention it, but Russian heat wave of 2010...


I was just thinking about that the other day. Moscow is at close to 56 degrees North latitude. Most of America lies between 30 degrees and 45 degrees North. If it can be 90+ for over a month straight at Moscow with several days around 100, just imagine what it could possibly do in America with the right weather pattern. You place that same pattern in America, and you'd be taking 100-110+ for days on end.
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Quoting Grothar:


They all went right by you. Lucky

I will say who was lucky..The entire half of Southern Florida. If Wilma had not stalled over the Yucatan for two days, Wilma would have ripped across Florida with a very wide path of almost unimaginable destruction. Had she made landfall 40 or 50 miles north of were she it would have made it even more devastating.
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Quoting STXHurricanes2012:
Link
No one saw this coming! Thank you blob lol


too bad most of it is staying off shore.
Member Since: February 11, 2012 Posts: 0 Comments: 9732
409. etxwx
Quoting islandgirls:


Is it looking at you? Something or someone sure got its attention


Yup. I was standing on the dock on the other side of the pond when I took that pic. The cows always look at me when I come out since I'm the food lady and thus command their attention. :-)
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Link
No one saw this coming! Thank you blob lol
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Quoting RTSplayer:
OMG...

The dry air and heat over Texas killed almost all of that first wave of convection...

I was hoping a bit more consistent and widespread rain that that would happen...

As it is, only the immediate area around Brownsville, and also south of the border, is getting good rains..

I guess the good news is the AOI is re-firing back near it's original coordinates again, so maybe we'll get another chance over the next day or two.




and

Low clouds Gulf of Mexico LSU ESL

I got about 6 inches down here in brownsville! Falcon dam has gotten a foot and still going!!!
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Quoting RTSplayer:
So what's the word on this month's June?

With all the daily and monthly records set in so many places, I figure we will roll forward by ANOTHER month on the "Hottest 12 consecutive months in the U.S." records.


This may be the hottest U.S. June ever.

Just another quick (ironic) blob note before we move on, I think Bohonkweatherman got all that huge rain - the only rain that happened in centex.
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Not much heat relief coming, at least for the west... Maybe a little break in the Southeast...

Member Since: February 11, 2012 Posts: 83 Comments: 7844

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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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