Midwest heat wave generates a heat index of 131° in Iowa; Bret no threat

By: Dr. Jeff Masters , 1:18 PM GMT on July 19, 2011

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A unusually intense, long-lasting, and widespread heat wave with high humidities continues to plague the Central U.S. The heat index--how hot the air feels when factoring in both the temperature and the humidity--exceeded 100°F in twelve states on Monday and thirteen on Sunday, with the dangerous heat extending from Texas northwards to North Dakota, Minnesota, and Wisconsin. At least thirteen deaths are being blamed on the heat in the Midwest. The heat index hit a remarkable 131°F at Knoxville, Iowa on Monday, and a heat index in excess of 120° was recorded at numerous locations in Iowa, Minnesota, and Illinois.


Figure 1. Predicted maximum heat index for Thursday, July 21, 2011. Portions of 33 states are predicted to have a heat index in excess of 100°F. Image credit: NOAA.

A 1-in-7-year heat wave coming for the Eastern U.S.
The extreme heat will shift slowly eastwards this week, peaking in Chicago on Wednesday, Detroit and Pittsburgh on Thursday, and New York City and the mid-Atlantic states on Friday. Temperatures near 100°F are expected in Detroit on Thursday and New York City on Friday. Detroit has hit 100°F 18 different years in its 137-year record, and New York City 22 years out of the past 140 years, so this heat wave is expected to be about a 1 in 7 year event. While that makes it a notable heat wave, the most remarkable feature of this July 2011 U.S. heat wave is the humidity that has accompanied the heat. A heat index over 130°F, such as was observed yesterday in Iowa, is very rare in the U.S., and extremely dangerous. According to Christopher C. Burt, wunderground's weather historian, the only place in the world where a heat index over 130°F is common is along the shores of the Red Sea in the Middle East. A major reason for the remarkably high humidities accompanying the July 2011 Midwest heat wave is the record flooding the region experienced over the past three months. As pointed out by wunderground's climate change blogger Dr. Ricky Rood in his latest post, with hundreds of thousands of acres of farmland still inundated by flood waters, and soils saturated over much of the Upper Midwest, there has been plenty of water available to evaporate into the air and cause remarkably high humdities. This makes for a very dangerous situation, as the human body is not able to cool itself as efficiently when the humidity is high. The extreme heat will last through Sunday in the mid-Atlantic, but should end on Monday, when a cold front is expected to sweep across the region. However, the latest models suggest the heat will re-amplify over the Midwest next week.


Figure 2. Tropical Storm Bret at peak intensity, at 5:15 pm EDT on Monday, July 18, 2011. At the time, Bret was building an eyewall and had begun to clear out an eye. Image credit: NASA/GSFC.

Tropical Storm Bret weakens
Tropical Storm Bret enjoyed a brief burst of intensification yesterday afternoon that brought the storm's winds up to 65 mph. However, Bret has sucked in a lot of dry air today, and is now a much weaker storm with winds of just 50 mph. Satellite imagery shows that Bret has not improved in organization this morning, thanks to dry air to the northwest that has been blown into the storm's core by upper-level northwesterly winds. Wind shear is a high 20 - 25 knots, and is expected to remain in the high range for the next three days. The combination of high wind shear and dry air nearby should act to keep Bret from strengthening, and the storm should slowly decay as it heads out to sea over the next few days. Bret is not a threat to any land areas.

None of the reliable models predict tropical cyclone development over the remainder of the Atlantic through July 26.

Weakened Typhoon Ma-on nearing Japan
Typhoon Ma-on has weakened to minimal Category 1 typhoon with 75 mph winds, and is battering a large swath of the south coast of Japan with tropical storm-force winds, as the storm slides northeast along the coast. Ma-on is expected to turn eastwards out to sea by Wednesday, and is not likely to bring tropical storm-force winds to the troubled Fukushima Nuclear Plant.

Jeff Masters

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935. beell
Quoting PcolaDan:
Cantore tweet

@JimCantore
Jim Cantore
For my Met GEEKS out there: 9000 CAPE in North Dakota!! http://www.spc.noaa.gov/exper/mesoanalysis/new/vi ewsector.php?sector=13&parm=scp&underlay=1 #


Wow!

That would yield an updraft velocity of around 65-70 m/s.

Strong enough to float pumpkin sized hail.
Member Since: September 11, 2007 Posts: 141 Comments: 16200
Quoting emcf30:


Yea this is crazy


Hopefully that weather can help with the firefighting in Ontario around Lake Winnipeg. Here in the Upper Peninsula of Michigan, air quality was terrible from the smoke......felt like a vice on the lungs. Very piney smell to it.
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This thing is persistent, I would have thought this would be a tropical depression by now. But no, it's a 50-60 mph tropical storm according to recon, with a tropical depression/weak tropical storm appearance. It is trying though, with nearly half of the center under deep convection.

Member Since: July 6, 2010 Posts: 113 Comments: 31409
Quoting PcolaDan:
Cantore tweet

@JimCantore
Jim Cantore
For my Met GEEKS out there: 9000 CAPE in North Dakota!! http://www.spc.noaa.gov/exper/mesoanalysis/new/vi ewsector.php?sector=13&parm=scp&underlay=1 #


Yea this is crazy
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Quoting RukusBoondocks:
there is a lot of cyclonic turning in the atlantic hold on folks


Agreed, I am definitely seeing more spins than in recent days. Season seems to want to kick-in a little quicker this year.
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I've stopped "forecasting" Bret. Whatever I say he's going to do, he does something else. Not even the opposite, so I can do the "anti-forecasting" thing.

Bleh.
Member Since: October 25, 2005 Posts: 19 Comments: 21403
Invest 99

Wind: 30 MPH — Location: 33.2 64.3W — Movement: E

This area of disturbed weather has the potential for tropical development





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most of the models seem to be coming on board with a strong disturbance east of the islands in 4days time. dry air will not be be a problem as the disturbance is producing an abundabce of moisture at the moment. very strong vorticity. but little convergence and divergence.
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there is a lot of cyclonic turning in the atlantic hold on folks
Member Since: February 13, 2011 Posts: 0 Comments: 294
Arctic sea cover shrinking at record pace

The annual Arctic slush cup has begun to sizzle in earnest, with the worst July coverage yet reported by satellite monitoring.

Damaged by the early start to the melt season and then basked in much warmer air than normal, Arctic sea ice has shrunk so fast during the past few weeks that it's now dipped into record minimum territory for the time of year, according to the National Snow and Ice Data Center.

Arctic sea ice extent declined at a rapid pace through the first half of July, and is now tracking below the year 2007, which saw the record minimum September extent, the NSIDC reported in its latest sea ice update.

As of July 17, the area of the Arctic Ocean covered by ice had shrunk to 2.92 million square miles -- the smallest extent ever seen for mid-July since satellite monitoring began in the 1970s. It's 865,000 square miles below the average cover for that date seen between 1979 and 2000. A frozen polar bear-and-seal habitat larger than Alaska and California combined has been transformed into mostly open water.

Although maps generated by satellite analysis show the pack has retreated far north from the shores of Alaska's Beaufort and Chukchi seas, the extent of sea ice was particularly low in the Barents, Kara, and Laptev seas of the far northern Atlantic Ocean, and along Canada in Hudson and Baffin bays, the NSIDC reported.

During the first half of July, a high-pressure cell persisted over the northern Beaufort Sea, as it did in June, and is linked to the above-average air temperatures over much of the Arctic Ocean, the NSIDC report explained. To date in July, air temperatures over the North Pole were (11 to 14 degrees Fahrenheit) higher than normal.




For more details and analysis, plus NSIDC's usual collection of easy-to-read charts and maps, go to the sea ice portal.
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Thank you Pat that information is not what I am referring to.
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Quoting JrWeathermanFL:
How strong will Bret be by the 11:00 advisory

A.40
B.45
C.50
D.55
E.60
F.65
G.70
H.stronger

Im thinking C


B or C.
Member Since: July 6, 2010 Posts: 113 Comments: 31409
920. txjac
Quoting Patrap:
We could dunk Press in His Dress for Portlight and make it a dedicated booth.


5 Bucks a Pop..I'd drop a C-note easily



Awesome idea ...my aim is bad ...he could make a big amount off of me! Love to cook too!
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Quoting PcolaDan:
Cantore tweet

@JimCantore
Jim Cantore
For my Met GEEKS out there: 9000 CAPE in North Dakota!! http://www.spc.noaa.gov/exper/mesoanalysis/new/vi ewsector.php?sector=13&parm=scp&underlay=1 #

Crazy, not sure if i've seen that before. (not that I frequently checked mesoanalysis prior to the past 2 years)
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We could dunk Press in His Dress for Portlight and make it a dedicated booth.


5 Bucks a Pop..I'd drop a C-note easily

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Quoting Tazmanian:




we can get name storms too from in the ITCZ do you re call IVAN in 04?


They however are not apart of the ITCZ, and do not rely on the ITCZ to sustain themselves.
Member Since: July 8, 2005 Posts: 259 Comments: 23560
Operational Microwave Integrated Retrieval System


The operational Microwave Integrated Retrieval System (MIRS) aims to upgrade the NESDIS current operational Microwave Surface and Precipitation Products System (MSPPS) and build a one-stop shop for microwave products from various satellites with different instrumental configurations. With the capability of providing optimal and physically-based retrievals of atmospheric and surface state parameters, the operational MIRS will produce advanced near-real-time surface and precipitation products in all-weather and over all-surface conditions using brightness temperatures from the microwave instruments, which include AMSU-A and AMSU-B/MHS instruments on board of NOAA and EUMETSAT polar orbiting satellites, SSMIS on DMSP polar satellites and ATMS/CIM on NPP/NPOESS. The targeted operational products will include: vertical profiles of temperature and moisture, rainfall rate, total precipitable water, cloud liquid water, snow cover, snow water equivalent, sea ice concentration, ice water path, surface emissivity spectra and land surface temperature. These products will be made operationally available to users with different types (orbital, granule/Area of Interests, daily, monthly) and formats (HDF-EOS/HDF, NetCDF, BUFR, McIDAS and AWIPS) through a multi-year stratified phase approach.

With the current MiRS v5.0, the operational products from NOAA-18, NOAA-19, and MetOp-A include: temperature profile over ocean, moisture profiles over ocean and non-coastal land, total precipitable water over ocean and non-costal land, cloud liquid water over ocean, rain water path, ice water path, rainfall rate, snow cover, sea ice concentration, snow water equivalent, land surface temperature, surface emissivity over land and snow for all AMSU-A and MHS channels. The operational products from DMSP SSMIS include: total precipitable water over ocean, cloud liquid water over ocean, rain water path, ice water path, rainfall rate, snow cover, sea ice concentration, snow water equivalent, land surface temperature, surface emissivity over land and snow for all SSMIS channels. The SSMIS temperature and moisture profiles over ocean are also made available to users as demo products.

The MIRS retrospective data have being archived since August 30, 2007 starting from version 1.0, and can be acquired from the National Climatic Data Center and the Comprehensive
Large Array-data Stewardship System.



Surface Temperature

Please click the small images or the links to view big images


DMSP F16

NOAA 18

NOAA 19

METOP A

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Quoting Patrap:
We need a wunderground Fishing rodeo...


Apps, epirbs, NOAA radios,..Hurricane Prep, climate change Booth, a picnic and a Party with Music,food,and tainment' too..


And a dunk booth of course.
I nominate JFV for the dunk booth.
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Quoting CybrTeddy:


Seems to be all in the ITCZ at this time.




we can get name storms too from in the ITCZ do you re call IVAN in 04?
Member Since: May 21, 2006 Posts: 5091 Comments: 114701
Quoting TropicalAnalystwx13:
Rut-Roh:



Seems to be all in the ITCZ at this time.
Member Since: July 8, 2005 Posts: 259 Comments: 23560
How strong will Bret be by the 11:00 advisory

A.40
B.45
C.50
D.55
E.60
F.65
G.70
H.stronger

Im thinking C
Member Since: Posts: Comments:
Cantore tweet

@JimCantore
Jim Cantore
For my Met GEEKS out there: 9000 CAPE in North Dakota!! http://www.spc.noaa.gov/exper/mesoanalysis/new/vi ewsector.php?sector=13&parm=scp&underlay=1#
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I have a weather question does anyone know if noaa polar orbiting satellites transmit l.i.r.t or do they just transmit a.p.t. and h.r.p.t. Do I have to receive this from the goes satellite. Thank you
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Quoting BahaHurican:
Depends on who volunteers, or is volunteered, to be dunked...


Oh yea, I can make a looooong list of write-in candidates, we could sell tickets and make some big bucks....lol...
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907. BDAwx
well hey!
I see you guys were looking for Bermuda earlier :)
I'm thanking pre-99L for its rains...
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Quoting EYEStoSEA:
LOLOL....now that's a real well thought out party plan....dunkin booth would go over exceptionally well...I would think.... :O
Depends on who volunteers, or is volunteered, to be dunked...
Member Since: October 25, 2005 Posts: 19 Comments: 21403
Easily.

We need to form a committee
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LOLOL....now that's a real well thought out party plan....dunkin booth would go over exceptionally well...I would think.... :O
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Yesterday someone compared Bret's structure to the Greek storms back in 2005...

5PM headline:
...DISORGANIZED BRET MAINTAINING INTENSITY FOR NOW BUT LIKELY TO WEAKEN SOON...

First reaction was that the headline is nearly identical to any of those for those Greek storms(Epsilon, ect..)

just a thought since the comparison was made yesterday.
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902. txjac
Quoting Patrap:
We need a wunderground Fishing rodeo...


Apps, epirbs, NOAA radios,..Hurricane Prep, climate change Booth, a picnic and a Party with Music,food,and tainment' too..


And a dunk booth of course.



WooHoo ...party at Pats!
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Rut-Roh:

Member Since: July 6, 2010 Posts: 113 Comments: 31409
We need a wunderground Fishing rodeo...


Apps, epirbs, NOAA radios,..Hurricane Prep, climate change Booth, a picnic and a Party with Music,food,and tainment' too..


And a dunk booth of course.
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HurryCane - I hear ya...

Good night and may the Hurricane Gods keep us safe for yet another season.

Although this is looking like it will be an interesting season...
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....get da Wookie some Irish Spring
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....Luke Frywalker....;^)
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what do we have here


EP, 04, 2011072000, , BEST, 0, 131N, 993W, 65, 987, HU



all so note the mb it drop from 994 too 987
Member Since: May 21, 2006 Posts: 5091 Comments: 114701
892. beell
EYES,
I thank you and most of eastern Harris County thanks you!
Member Since: September 11, 2007 Posts: 141 Comments: 16200
did someone say Cabo?

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Quoting Hurrykane:


LOL! How are you tonight, Dakster?

The NAM is a regional model NAM = North American Mesosscale model


Good and you?? Yeah -- I had a momentary mind fart...

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887. SLU
Quoting ackee:
I would agree with u does seem like the GFS is having and up and down year thus far seem like the CMC has improve somewhat


Yep
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Quoting beell:


Personal tip:

First, if you can, cover your mout before you sneeze. If you can't, clean your monitor, then look for Bermuda.


That is snot funny...
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Bret still appears to be maintaining 50 mph, although the NHC may lower it some based on appearance.
Member Since: July 6, 2010 Posts: 113 Comments: 31409

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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.