Major severe thunderstorm outbreak expected; U.S. drought intensifies

By: Dr. Jeff Masters , 2:16 PM GMT on July 26, 2012

A dangerous outbreak of organized severe thunderstorms with strong, damaging winds is expected this afternoon from Ohio eastwards through Pennsylvania and into New England, says NOAA's Storm Prediction Center (SPC). They have put the region, which includes Columbus, Pittsburgh, Philadelphia, and New York City, in their "Moderate Risk" area for severe weather, just one notch below the highest level of alert. Much of the region is also under advisories for extreme heat, with temperatures in the upper 90s expected. This extreme heat will help energize the thunderstorms by making the atmosphere very unstable. A cold front passing through the region will trigger the severe weather episode beginning around 2 pm EDT this afternoon, near the Indiana/Ohio border. This front already triggered a round of severe thunderstorms early this morning across Michigan, which knocked out power to 16,000 customers. This afternoon, severe thunderstorms may organize into a complex that features a bow-shaped echo. If such a complex brings violent straight-line winds in excess of 58 mph (93 km/hr) over a swath of at least 240 miles (about 400 km), it will be called a derecho (from the Spanish phrase for "straight ahead".) The atmosphere is not as unstable as was the case for the June 29 - 30 Mid-Atlantic and Midwest derecho, however. That storm was one of the most destructive and deadly fast-moving severe thunderstorm complexes in North American history. It killed 22 people, knocked out power to at least 3.7 million customers, and did hundreds of millions in damage.


Figure 1. Severe weather risk for Thursday, July 26, 2012, from NOAA's Storm Prediction Center (SPC).

U.S. drought intensifies
The great U.S. drought of 2012 held constant in size but grew more intense over the past week, said NOAA in their weekly U.S. Drought Monitor report issued Thursday, July 26. The area of the contiguous U.S. covered by drought stayed constant at 64% , but the area covered by severe or greater drought jumped from 42% to 46%. These are truly historic levels of drought, exceeded only during the great Dust Bowl drought of the 1930s and a severe drought in the mid-1950s. The July 2012 drought is second only to the great Dust Bowl drought of July 1934 in terms of the area of the contiguous U.S. covered by moderate or greater drought (if we assume the drought conditions measured in mid-July are representative of the entire month of July, which is a reasonable approximation given the lastest drought forecast.) The five months with the greatest percent area in moderate or greater drought, since 1895, now look like this:

1) Jul 1934, 80%
2) Jul 2012, 64%
3) Dec 1939, 60%
4) Jul 1954, 60%
5) Dec 1956, 58%

If we consider the area of the contiguous U.S. covered by severe or greater drought, drought conditions as of July 24, 2012 now rank in 3rd place:

1) Jul 1934, 63%
2) Sep 1954, 50%
3) Jul 2012, 46%
4) Dec 1956, 43%
5) Aug 1936, 43%


Figure 2. July 24, 2012 drought conditions showed historic levels of drought across the U.S., with 64% of the contiguous U.S. experiencing moderate or greater drought, and 46% of the county experiencing severe or greater drought. Image credit: U.S. Drought Monitor.

Extreme heat continues in the Heartland
St. Louis, Missouri's summer of extreme heat reached record levels on Wednesday, when the city hit 108°F. This marked the 11th day this summer in St. Louis with temperatures of at least 105°F, beating the old record of ten such days in 1934. The minimum temperature in the city fell to just 86°F, tying with July 24, 1901, as the warmest minimum temperature ever recorded in the city. St. Louis has seen just 0.53" inches of rain this month, far below the normal 3.35" it usually records by this point in July.

Jeff Masters

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120hrs
Member Since: March 16, 2012 Posts: 134 Comments: 8005
114hrs and the pressure is dropping
Member Since: March 16, 2012 Posts: 134 Comments: 8005
108hrs and theres something off Africa, will it persist?
Member Since: March 16, 2012 Posts: 134 Comments: 8005
84 hrs
Member Since: March 16, 2012 Posts: 134 Comments: 8005
78 hrs and theres a low coming off Africa.
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1344. Patrap
current c2small

wait for it,..

Member Since: July 3, 2005 Posts: 454 Comments: 144373
1343. Patrap
NOAA Space Weather Prediction Center Space Weather Alerts

Alerts in Graphical Timelines: Past 7 days and Currently in Effect
Alerts in Text Format: Current month and Previous month
Member Since: July 3, 2005 Posts: 454 Comments: 144373
Depression cloud.

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60hrs and no real development
Member Since: March 16, 2012 Posts: 134 Comments: 8005
1340. Patrap
..and If the Blog yer in starts Playing different tunes, I'll see you on the dark Side of the Blog..
Member Since: July 3, 2005 Posts: 454 Comments: 144373
1338. geepy86
Quoting EricSFL:
Amazing view of Florida at night. Image credit: NASA

I'm so glad I live in a dark spot
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Drought...

Our energy system depends on water. About half of the nation's water withdrawals every day are just for cooling power plants. In addition, the oil and gas industries use tens of millions of gallons a day, injecting water into aging oil fields to improve production, and to free natural gas in shale formations through hydraulic fracturing - All told, we withdraw more water for the energy sector than for agriculture. Unfortunately, this relationship means that water problems become energy problems that are serious enough to warrant high-level attention.

http://blogs.scientificamerican.com/plugged-in/20 12/07/26/will-a-lack-of-water-threaten-u-s-energy- production/
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48hrs
Member Since: March 16, 2012 Posts: 134 Comments: 8005
36 hrs and a barely closed 1014mb low in C ATL
Member Since: March 16, 2012 Posts: 134 Comments: 8005
1334. EricSFL
Amazing view of Florida at night. Image credit: NASA
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Quoting TropicalAnalystwx13:

The MJO comes back then.


Yep but will it be Strong enough to stir up trouble..

Tune in next week for "As the MJO Turns".....
Member Since: September 8, 2008 Posts: 2 Comments: 1340
24 hrs and not much happening
Member Since: March 16, 2012 Posts: 134 Comments: 8005
00Z gfs is running
Member Since: March 16, 2012 Posts: 134 Comments: 8005
00z GFS is running. Let's see if it has something developing or continues void on development.
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Quoting BahaHurican:
Hey mel! How's SoCal?

I hear u haven't been getting as much rain as u would like...



We don't LIKE rain!!! Live in San Diego so we only get rain in the winter. Nov maybe..dry last year.

It's been HUMID here though. Have the a/c on early this year.

I know we sound spoiled but honestly...the weather is whacked. Paul is saying that the weather is more hot than...I hear David bitching...Emmy.

And we have to convince people.

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I cant wait for when the mjo comes back.
Member Since: March 16, 2012 Posts: 134 Comments: 8005
Quoting canehater1:
The MJO remained active but was weak during the past week with the enhanced phase of the MJO centered over the Maritime Continent. Other types of tropical subseasonal variability continue to result in anomalous convection across the global tropics. The Indian monsoon circulation index has been weaker than normal for much of the summer, contributing to below normal rainfall for most of India since the beginning of June. Meanwhile, the North America monsoon remained active for the second consecutive week.

Typhoon Vicente developed near Luzon and intensified rapidly to become a powerful Category 4 typhoon as it approached southeast China. On July 23, Typhoon Vicente made landfall southwest of Hong Kong. Vicente has weakened since making landfall and its remnants are forecast to track west across northern Vietnam.

During Week-1, the weak MJO signal along with model guidance indicates increased chances for rainfall in the upper tercile across the Philippines, Taiwan, and the western Pacific. Enhanced convection and warmer-than-normal SSTs support elevated chances for tropical cyclone development in the western Pacific. Early in the period, heavy rain in northern Vietnam is expected along the path of former typhoon Vicente. The North America monsoon is forecast to remain active with above normal rainfall favored from Sonora north to the southwest U.S. The suppressed phase of a weak MJO signal is expected to favor below normal rainfall across the eastern Indian Ocean, Sumatra, and southern India. It should be noted that an ongoing cyclonic circulation may bring heavy rainfall to Uttar Pradesh and Madhya Pradesh, in north-central India, at the beginning of this period.

The week-2 outlook is uncertain due to a continued weak MJO signal and is largely based on model guidance. Above-normal rainfall is expected to continue across the Philippines, western Pacific, and may extend north to South Korea and southern Japan depending on the track of expected tropical cyclone activity. Elevated chances for tropical cyclone development are forecast in the South China Sea and western Pacific. Below normal rainfall is expected to expand eastward to the western Maritime Continent. Late in week-2 and beyond this period, conditions may become more favorable for tropical cyclone development in the main development region of the tropical Atlantic.

(From Global Trop Weather Outlook)

LinkLink

The MJO comes back then.
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1326. Patrap
Well this cant be good

LASCO

Member Since: July 3, 2005 Posts: 454 Comments: 144373
1325. Patrap
Quoting KEEPEROFTHEGATE:
sunset/sunrise summit camp





Is that one Guy holding a Fresca?
Member Since: July 3, 2005 Posts: 454 Comments: 144373
1324. KEEPEROFTHEGATE (Mod)
sunset/sunrise summit camp



Member Since: July 15, 2006 Posts: 200 Comments: 65791
The MJO remained active but was weak during the past week with the enhanced phase of the MJO centered over the Maritime Continent. Other types of tropical subseasonal variability continue to result in anomalous convection across the global tropics. The Indian monsoon circulation index has been weaker than normal for much of the summer, contributing to below normal rainfall for most of India since the beginning of June. Meanwhile, the North America monsoon remained active for the second consecutive week.

Typhoon Vicente developed near Luzon and intensified rapidly to become a powerful Category 4 typhoon as it approached southeast China. On July 23, Typhoon Vicente made landfall southwest of Hong Kong. Vicente has weakened since making landfall and its remnants are forecast to track west across northern Vietnam.

During Week-1, the weak MJO signal along with model guidance indicates increased chances for rainfall in the upper tercile across the Philippines, Taiwan, and the western Pacific. Enhanced convection and warmer-than-normal SSTs support elevated chances for tropical cyclone development in the western Pacific. Early in the period, heavy rain in northern Vietnam is expected along the path of former typhoon Vicente. The North America monsoon is forecast to remain active with above normal rainfall favored from Sonora north to the southwest U.S. The suppressed phase of a weak MJO signal is expected to favor below normal rainfall across the eastern Indian Ocean, Sumatra, and southern India. It should be noted that an ongoing cyclonic circulation may bring heavy rainfall to Uttar Pradesh and Madhya Pradesh, in north-central India, at the beginning of this period.

The week-2 outlook is uncertain due to a continued weak MJO signal and is largely based on model guidance. Above-normal rainfall is expected to continue across the Philippines, western Pacific, and may extend north to South Korea and southern Japan depending on the track of expected tropical cyclone activity. Elevated chances for tropical cyclone development are forecast in the South China Sea and western Pacific. Below normal rainfall is expected to expand eastward to the western Maritime Continent. Late in week-2 and beyond this period, conditions may become more favorable for tropical cyclone development in the main development region of the tropical Atlantic.

(From Global Trop Weather Outlook)

LinkLink
Member Since: September 8, 2008 Posts: 2 Comments: 1340
Also noting again how all the fronts and low pressure lines are just rolling over the top of this high... not doing much at all to split the ridge at all... :o(

Last year was bad enough. We really don't need another hurricane or hurricanes plural in the Bahamas this year.

And for those who think it's fun... NOT!
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1321. Patrap






Member Since: July 3, 2005 Posts: 454 Comments: 144373
Quoting BahaHurican:
So it's not reaching the ground?
Not where he was. There's plenty of NYC and area cams to see what's going on...more of a heavy mist at most. But there's certainly heavy rain elsewhere. Just not near NYC or Long Island.
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This is the ridge from the nether place... I sure hope this breaks down sooner rather than later...

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1317. Patrap
..is da Mojo Risin ?

Member Since: July 3, 2005 Posts: 454 Comments: 144373
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Quoting BahaHurican:
YOu mean it depends on the MJO?



Yes.
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Quoting CosmicEvents:
Re: 1301
.
I don't believe that this image accurately conveys the situation. It makes it appear that the storms are stronger and Long Island is right in the thick of it. I just spoke with Uncle Vinnie on the Suffolk county south shore and he said it was fine. He was out walking his dogs on the beach. Here's the radar:
.
So it's not reaching the ground?
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Re: 1301
.
I don't believe that this image accurately conveys the situation. It makes it appear that the storms are stronger and Long Island is right in the thick of it. I just spoke with Uncle Vinnie on the Suffolk county south shore and he said it was fine. He was out walking his dogs on the beach. Here's the radar:
.
Link
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Quoting KoritheMan:


At this point development weighs pretty heavily on the MJO. Conditions are definitely becoming more favorable.
YOu mean it depends on the MJO?

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Glad to see rain for those who need it badly...
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Quoting RussianWinter:
Models are coming soon right? Do you think any there is any chance they will change their mind on Cape Verde?


At this point development weighs pretty heavily on the MJO. Conditions are definitely becoming more favorable.
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Quoting melwerle:
Thanks Press for hooking us up tonight. I am forever grateful.

Melissa
Hey mel! How's SoCal?

I hear u haven't been getting as much rain as u would like...

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1307. KEEPEROFTHEGATE (Mod)
Quoting melwerle:


Nope...press is HOT. I've seen him in his best bar outfit. He's boss and don't mess with him.
iam sure he is no doubt i was just ribbing him a bit
Member Since: July 15, 2006 Posts: 200 Comments: 65791
Models are coming soon right? Do you think any there is any chance they will change their mind on Cape Verde?
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Quoting Doppler22:
Im leaving for tonight... with some rumbles of thunder in the distance night all!
Take care, Dopp
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...TROPICAL WAVES...

TROPICAL WAVE EXTENDS W OF THE CAPE VERDE ISLANDS FROM 20N31W TO
10N32W MOVING W AT 20 KT. THE WAVE IS WITHIN A DEEP LAYER
MOISTURE MAXIMUM AS INDICATED ON TOTAL PRECIPITABLE WATER
IMAGERY. A LARGE PLUME OF AFRICAN DUST IS HOWEVER SUPPRESSING
SIGNIFICANT CONVECTION. SCATTERED RAIN AND SHOWERS ARE WITHIN
120 NM OF THE WAVE AXIS.

TROPICAL WAVE EXTENDS FROM 23N47W TO 11N49W MOVING W AT 15 KT.
THE WAVE IS WITHIN A DEEP LAYER MOISTURE MAXIMUM AS INDICATED ON
TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED RAIN AND SHOWERS ARE
WITHIN 120 NM OF THE WAVE AXIS.

TROPICAL WAVE EXTENDS JUST E OF THE YUCATAN PENINSULA FROM
22N86W TO 15N87W MOVING W AT 15 KT. THE WAVE EXHIBITS BROAD LOW
LEVEL CYCLONIC TURNING. WIDELY SCATTERED MODERATE CONVECTION IS
OVER CENTRAL AMERICA AND THE W CARIBBEAN FROM 15N-22N BETWEEN
83W-90W.

...TROPICAL WAVES...

TROPICAL WAVE EXTENDS W OF THE CAPE VERDE ISLANDS FROM 20N31W TO
10N32W MOVING W AT 20 KT. THE WAVE IS WITHIN A DEEP LAYER
MOISTURE MAXIMUM AS INDICATED ON TOTAL PRECIPITABLE WATER
IMAGERY. A LARGE PLUME OF AFRICAN DUST IS HOWEVER SUPPRESSING
SIGNIFICANT CONVECTION. SCATTERED RAIN AND SHOWERS ARE WITHIN
120 NM OF THE WAVE AXIS.

TROPICAL WAVE EXTENDS FROM 23N47W TO 11N49W MOVING W AT 15 KT.
THE WAVE IS WITHIN A DEEP LAYER MOISTURE MAXIMUM AS INDICATED ON
TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED RAIN AND SHOWERS ARE
WITHIN 120 NM OF THE WAVE AXIS.

TROPICAL WAVE EXTENDS JUST E OF THE YUCATAN PENINSULA FROM
22N86W TO 15N87W MOVING W AT 15 KT. THE WAVE EXHIBITS BROAD LOW
LEVEL CYCLONIC TURNING. WIDELY SCATTERED MODERATE CONVECTION IS
OVER CENTRAL AMERICA AND THE W CARIBBEAN FROM 15N-22N BETWEEN
83W-90W.

....
CARIBBEAN SEA...
A TROPICAL WAVE IS PRODUCING CONVECTION OVER THE WESTERN
CARIBBEAN. SEE ABOVE. A 1004 MB LOW IS CENTERED OVER N COLOMBIA
NEAR 8N75W. ISOLATED MODERATE CONVECTION IS OVER N COLOMBIA AND
VENEZUELA. WIDELY SCATTERED MODERATE CONVECTION IS OVER CUBA
BETWEEN 76W-84W. 15-30 KT TRADEWINDS ARE NOTED BETWEEN THE
TROPICAL WAVES. STRONGEST SURFACE WINDS ARE JUST N OF N
COLOMBIA. SCATTERED MODERATE CONVECTION IS NOTED OVER E
NICARAGUA AND E HONDURAS FROM 12N-15N BETWEEN 83W-85W. SCATTERED
SHOWERS ARE OVER HISPANIOLA...PUERTO RICO...AND THE LEEWARD
ISLANDS. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED
OVER THE E CARIBBEAN NEAR 15N62W WITH STRONG SUBSIDENCE. AN
UPPER LEVEL TROUGH IS OVER THE NW CARIBBEAN ENHANCING
CONVECTION. EXPECT THE TROPICAL WAVE TO MOVE W OVER THE NEXT 24
HOURS WITH CONVECTION. ALSO EXPECT CONVECTION OVER PANAMA AND
THE SW CARIBBEAN OVER THE NEXT 24 HOURS.

I think I haven't seen so many ULHs for a while in the summer.
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Im leaving for tonight... with some rumbles of thunder in the distance night all!
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1302. Patrap
Quoting melwerle:


Nope...press is HOT. I've seen him in his best bar outfit. He's boss and don't mess with him.


I've dined with him numerous times here and in Fla, he is very well mannered and all for his Height.


: )

Member Since: July 3, 2005 Posts: 454 Comments: 144373
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Thanks Press for hooking us up tonight. I am forever grateful.

Melissa
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Quoting KEEPEROFTHEGATE:


yeah
in your dreams
and when
the sun shines


Nope...press is HOT. I've seen him in his best bar outfit. He's boss and don't mess with him.
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