Record Atlantic SSTs continue in the hurricane Main Development Region

By: Dr. Jeff Masters , 8:03 PM GMT on May 15, 2010

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Sea Surface Temperatures (SSTs) in the Atlantic's Main Development Region for hurricanes had their warmest April on record, according to an analysis of historical SST data from the UK Hadley Center. SST data goes back to 1850, though there is much missing data before 1910 and during WWI and WWII. The area between 10°N and 20°N, between the coast of Africa and Central America (20°W - 80°W), is called the Main Development Region (MDR) because virtually all African waves originate in this region. These African waves account for 85% of all Atlantic major hurricanes and 60% of all named storms. When SSTs in the MDR are much above average during hurricane season, a very active season typically results (if there is no El Niño event present.) SSTs in the Main Development Region (10°N to 20°N and 20°W to 85°W) were an eye-opening 1.46°C above average during April. This is the third straight record warm month, and the warmest anomaly measured for any month--by a remarkable 0.2°C. The previous record warmest anomalies for the Atlantic MDR were set in June 2005 and March 2010, at 1.26°C.


Figure 1. The departure of sea surface temperature (SST) from average for May 13, 2010. Image credit: NOAA/NESDIS.

What is responsible for the high SSTs?
As I explained in detail in a post on record February SSTs in the Atlantic, the Arctic Oscillation (AO) and its close cousin, the North Atlantic Oscillation (NAO), are largely to blame for the record SSTs. The AO and NAO are climate patterns in the North Atlantic Ocean related to fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores-Bermuda High. If the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), this creates a weak Azores-Bermuda High, which reduces the trade winds circulating around the High. During December - February, we had the most negative AO/NAO since records began in 1950, and this caused trade winds between Africa and the Lesser Antilles Islands in the hurricane Main Development Region to slow to 1 - 2 m/s (2.2 - 4.5 mph) below average. Slower trade winds mean less mixing of the surface waters with cooler waters down deep, plus less evaporational cooling of the surface water. As a result, the ocean heated up significantly, relative to normal, over the winter. Negative AO/NAO conditions have been dominant much of this spring as well, resulting in further anomalous heating of the MDR waters. This heating is superimposed on the very warm global SSTs we've been seeing over the past few decades due to global warming. Global and Northern Hemisphere SSTs were the 2nd warmest on record this past December, January, and February, the warmest on record in March, and will likely be classified as the warmest or second warmest on record for April, since NASA just classified April as the warmest April on record for the globe. We are also in the warm phase of a decades-long natural oscillation in Atlantic ocean temperatures called the Atlantic Multi-decadal Oscillation (AMO). This warm phase began in 1995, and has been partially responsible for the high levels of hurricane activity we've seen since 1995.

What does this imply for the coming hurricane season?
The high April SST anomaly does not bode well for the coming hurricane season. The three past seasons with record warm April SST anomalies all had abnormally high numbers of intense hurricanes. Past hurricane seasons that had high March SST anomalies include 1969 (0.90°C anomaly), 2005 (1.19°C anomaly), and 1958 (0.97°C anomaly). These three years had 5, 7, and 5 intense hurricanes, respectively. Just two intense hurricanes occur in an average year. The total averaged activity for the three seasons was 15 named storms, 11 hurricanes, and 6 intense hurricanes (an average hurricane season has 10, 6, and 2.) Both 1958 and 2005 saw neutral El Niño conditions, while 1969 had a weak El Niño.

The SSTs are already as warm as we normally see in July between Africa and the Caribbean, and we have a very July-like tropical wave approaching the Lesser Antilles Islands this weekend. However, wind shear is still seasonably high, and the tropical waves coming off of Africa are still too far south to have much of a chance of developing. The GFS model is indicating that shear will start to drop over the Caribbean the last week of May, so we may have to be on the watch for tropical storms forming in the Caribbean then.

For those of you interested in a more detailed look at the early season tropical weather outlook, consult the excellent wunderblogs of StormW and Weather456. I'll be back with a new post on Monday.

Jeff Masters

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1069. Patrap
That is Kinda funny I thought as well..Lil blips deep in the sheared tropics catches a few untrained eyes, but that Whoppa of a 980 Low dosent ?

Sheesh
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1068. xcool
im wait on cmc and ngp
Member Since: September 26, 2009 Posts: 2 Comments: 15670
Quoting CaribBoy:
00Z GFS shows two low pressure systems forming in the caribbean... but this is still in the long range so they are likely ghosts.


I'm surprised nobody has yet mentioned the persistent forecast of a subtropical cyclone off the eastern seaboard in the next few days. The GFS, NOGAPS, and CMC have all been consistent in developing this.
Member Since: March 7, 2007 Posts: 575 Comments: 20553
Quoting WaterWitch11:
hi bord,
there was just one that caught my eye, it was a 3.9 in ventura county. i have been watching a while now and they don't get them that often. but a long time ago one of the channel islands cracked from an eq. i read it in a book, i can't seem to find it one the computer.

Hopefully the Earth stays quiet! Latest update on "E" from the UK/Iceland Met offices:

Volcanic ash update. — 0257 on Monday 17 May 2010

Latest information from the Icelandic Met Office indicates that the Eyjafjallajokull volcano continues to erupt. It is estimated that the current height of the ash plume is still between 23000 and 26000 ft (7 to 8 km), with extremes at 29500 feet (9 km). Following the spread of the plume southeastwards, there were numerous reports received during Sunday. These ranged from a milky sky in South Uist, smells of sulpher near Newcastle, visible ash clouds observed (from the both the ground and the air) in the skies above northern England, and at the end of Sunday of ash deposits in Waddington and Conningsby. Issued at 0252 on Mon 17 May 2010.

Member Since: August 25, 2009 Posts: 20 Comments: 6785
00Z GFS shows two low pressure systems forming in the caribbean... but this is still in the long range so they are likely ghosts.
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1064. Skyepony (Mod)
GISS put out the Apr numbers..April was easily hottest NH on record 132..1998 it was 81.

We've got a good shot at warmest year on record this year. With the thin ice that covered near average there thanks to the neg NAO & the heat, got to go with a record melt forecast for the year.
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hi bord,
there was just one that caught my eye, it was a 3.9 in ventura county. i have been watching a while now and they don't get them that often. but a long time ago one of the channel islands cracked from an eq. i read it in a book, i can't seem to find it one the computer.
Member Since: August 11, 2008 Posts: 3 Comments: 1606
1062. Patrap
We will have 100 year Cat 5protection.

We are building it everyday,..with Fed funding, but we could pay for it all if we got our share of the Billions in Oil Royalties that bypass the State.

All the info is available,,under COE "Task Force Guardian".
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1061. hydrus
Quoting tornadodude:
hey all,

hanging here at a coffee shop in Abilene, Texas, going to try to do some preliminary chasing today, just to get a feel for the area. Probably wont be able to do the webcam, as my trial ran out for my tethering program. As soon as I get back I'm investing in an air-card
I was listening to you and Oz today. Hope your chase is safe and successful.
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Quoting Patrap:


i didn't realize they were doing this. thanks for posting.
Member Since: August 11, 2008 Posts: 3 Comments: 1606
1059. Patrap
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Quoting WaterWitch11:
We Americans demand the government "step up to the plate" and fix the NOLA levy system NOW!!!!

i wouldn't hold your breath bord

I am not, but there is no need to endanger the lives of over 750,000 NOLA Metro residents.

On a positive note, you folks in CA haven't had any major tremors this weekend. That "character" who is forecasting a large quake is not very wise!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
We Americans demand the government "step up to the plate" and fix the NOLA levy system NOW!!!!

i wouldn't hold your breath bord
Member Since: August 11, 2008 Posts: 3 Comments: 1606
Quoting BDAwx:
did you guys know that Bermuda was colonized as a direct result of a major hurricane - in July 1609.


I didn't know that. Interesting. Thanks for sharing.
Member Since: March 7, 2007 Posts: 575 Comments: 20553
Quoting GainesvilleGator:
Here is an excerpt from the Internet:

"Eyjafjallajokul (pronounced ay-yah-FYAH-lah-yer-kuhl) erupted in April for the first time in nearly two centuries. During its last eruption, starting in 1821, its emissions rumbled on for two years."

Not that hard to pronounce. Lets all say Eyjafjallajokul five times really fast. Kuhl !

Has anyone started a contest on when Katla will erupt?



From the "Eruptions Blog", a blogger posted a link, we need Grothar to translate, it's in Icelandic, stating "E" has already dumped more ash than in the 1821-23 eruption. Ans it's still going strong, no visual today, fog and clouds have covered the summit.

At 250 million m3 the Eyja ash/lava emission has already exceeded that of the 1821-23 eruption.

But it's still much less than Katla in 1918 (700 million m3).

RÚV newsclip: http://dagskra.ruv.is/sjonvarpid/4497994/2010/05/16/1/

Posted by: Anna, Reykjavík | May 16, 2010 4:47 PM
Member Since: August 25, 2009 Posts: 20 Comments: 6785
1054. Patrap
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1053. Skyepony (Mod)
Mottt~ It was. They showed what looked like underwater plumes in shallow blue clear water. It was on 6, not accu..

Looks like a research boat it going to check it out.
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1052. Patrap
Inner Harbor Navigation Canal surge barrier work proceeding smoothly, corps says
By Masako Hirsch, The Times-Picayune
May 13, 2010, 8:13PM


Construction of the Inner Harbor Navigation Canal surge barrier is on track and should be completed by its June 2011 deadline, Army Corps of Engineers officials said during a tour of the work Thursday.

Construction began last May on the barrier, which is one way the corps plans on protecting some of the region's most vulnerable areas from surges created by so-called "100-year" storms, or hurricanes with a 1 percent chance of occurring each year. The barrier will block surge originating in the Gulf of Mexico and Lake Borgne from entering the Industrial Canal, which was blamed for some of the catastrophic levee failures in Hurricane Katrina.

With the start of hurricane season just 16 days away, corps officials said they are pleased with the progress.



View full sizeJohn McCusker/The Times-PicayuneMayor Mitch Landrieu, right, called the progress on the surge barrier 'a great first step,' but noted the possibility of dangerous storms still exists."We're much better off heading into this hurricane season than we have been before, and that includes last year," said Karen Durham-Aguilera, civilian director of the corps' Task Force Hope, which oversees much of the area's levee construction.

The barrier project consists of walls that will be 24 to 26 feet above sea level, and two navigation gates that will be placed across the Gulf Intracoastal Waterway on the New Orleans side of the barrier and at Bayou Bienvenue.

The corps is set to finish construction of the barrier's walls by July 4 and the floodgates by the start of next year's hurricane season.

According to Brig. Gen. Michael Walsh, commander of the corps' Mississippi Valley Division, the agency expects to complete work on improvements to the hurricane risk reduction system on both sides of the river to provide the congressionally mandated 100-year protection level with the $14.6 billion already appropriated for the work. After the projects are completed, they will be turned over to the state, which will assume their annual maintenance and operation costs.

Despite the size of the barrier, Walsh said it does not take away all the risk of storms like Katrina, which had 30-foot waves. Katrina was considered a 400-year event in studies of its effects conducted by corps scientists.

"All of the other requirements need to be looked at," including evacuation, zoning issues and insurance, to assure additional protection, Walsh said.

The corps also is still working on a study aimed at recommending to Congress additional improvements that would provide New Orleans and other Louisiana coastal communities protection from the equivalent of a Category 5 hurricane. The Louisiana Coastal Protection and Restoration Study, still awaiting approval in the office of the Assistant Secretary of the Army, recommends additional study before several combinations of higher levees and coastal restoration projects can be recommended to Congress for authorization and funding.

New Orleans Mayor Mitch Landrieu called the progress on the surge barrier "a great first step," but noted the possibility of dangerous storms still exists.

"It reminds us once again in a sobering way, the continuing threat that people face in South Louisiana," Landrieu said.

Landrieu also emphasized the need for preparation and evacuation plans.

"Prepare yourself," Landrieu said. "Be aware that hurricane season is on us. We are still vulnerable."
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Quoting GainesvilleGator:
Has anyone started a contest on when Katla will erupt?



That would be on the same level as having a contest as to when the Cubs will win the world series. ;>)
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting TexasGulf:
My main concern with the terms 100-year storm is that the federal government is proceeding as if a Katrina like event won't likely happen again this century.

As a roughly 50-year event (which Katrina was in my opinion), there is a 1:50 chance each year for a similar storm to hit New Orleans. Between now and 2020, there is a 1/5 chance of it happening again. By 2030, there is a 2/5 chance of New Orleans getting hit by another Katrina sized storm.

My concern is that, by building the levees and locks to withstand a strong Cat-3 hurricane storm surge, they are asking for failure in the future. Each year is a 1:50 gamble that it won't happen... but if you lose, the levees get over topped and the city gets flooded to the rooftops again. That's almost the same odds as having a '0' turn up on the roulette wheel... or about the same odds as cutting a deck of cards and the Ace of Spades comes up.

Why stop at reinforcing the levees for a 100-year storm (by definition) that actually occurs every 50-years per prior history. If an actual 100-year storm comes along, it will dwarf Katrina.




i agree. it's the silence scream.

Member Since: August 11, 2008 Posts: 3 Comments: 1606
Quoting TexasGulf:
My main concern with the terms 100-year storm is that the federal government is proceeding as if a Katrina like event won't likely happen again this century.

As a roughly 50-year event (which Katrina was in my opinion), there is a 1:50 chance each year for a similar storm to hit New Orleans. Between now and 2020, there is a 1/5 chance of it happening again. By 2030, there is a 2/5 chance of New Orleans getting hit by another Katrina sized storm.

My concern is that, by building the levees and locks to withstand a strong Cat-3 hurricane storm surge, they are asking for failure in the future. Each year is a 1:50 gamble that it won't happen... but if you lose, the levees get over topped and the city gets flooded to the rooftops again. That's almost the same odds as having a '0' turn up on the roulette wheel... or about the same odds as cutting a deck of cards and the Ace of Spades comes up.

Why stop at reinforcing the levees for a 100-year storm (by definition) that actually occurs every 50-years per prior history. If an actual 100-year storm comes along, it will dwarf Katrina.



They US Army Corp of Engineers need to shore up the levies around NOLA to withstand a CAT 4+ hurricane.

From chatting with Patrap and several other NOLA residents, we cannot afford to have another "Katrina type-catastrophe".

I believe that NOLA has the World's 4TH busiest port. We Americans demand the government "step up to the plate" and fix the NOLA levy system NOW!!!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
My main concern with the terms 100-year storm is that the federal government is proceeding as if a Katrina like event won't likely happen again this century.

As a roughly 50-year event (which Katrina was in my opinion), there is a 1:50 chance each year for a similar storm to hit New Orleans. Between now and 2020, there is a 1/5 chance of it happening again. By 2030, there is a 2/5 chance of New Orleans getting hit by another Katrina sized storm.

My concern is that, by building the levees and locks to withstand a strong Cat-3 hurricane storm surge, they are asking for failure in the future. Each year is a 1:50 gamble that it won't happen... but if you lose, the levees get over topped and the city gets flooded to the rooftops again. That's almost the same odds as having a '0' turn up on the roulette wheel... or about the same odds as cutting a deck of cards and the Ace of Spades comes up.

Why stop at reinforcing the levees for a 100-year storm (by definition) that actually occurs every 50-years per prior history. If an actual 100-year storm comes along, it will dwarf Katrina.


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1047. xcool
wow
Member Since: September 26, 2009 Posts: 2 Comments: 15670
1046. BDAwx
did you guys know that Bermuda was colonized as a direct result of a major hurricane - in July 1609.
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Quoting TexasGulf:
The Corps of Engineers reinforced the flood gates and levees in New Orleans to protect the canals against a surge during a Katrina-like storm which they call a Once-in-100-years event. They have this idea that Katrina or similar sized storm is a 100-year storm, or likely to happen only once per century.

I contend that history teaches otherwise, and that Katrina was a 50-year storm.

Hurricane Betsy made landfall on September 10th, 1965 at Grand Isle, Louisiana with a pressure of 948 mb, gusts of 160 miles per hour (mph), a forward speed of 22 mph and storm surge of 15.7 ft. New Orleans witnessed gusts of 135 mph and a 9.8 ft storm surge.

Hurricane Camille struck the Mississippi coast on August 17th, 1969 as a Category 5, with a pressure was 901 millibars and winds estimated at 175 mph. The storm surge was officially measured at 24.6 feet inside a surviving structure, but experts expect that it surpassed 28 feet.

Hurricane Katrina struck in 2005.

Can Katrina really be a Once-in-100-year event if storms of similar strength occurred 36-years and 40-years earlier? The definition of 100-year storm is based on the history of the region based on past climatology. Why would we assume that, with rising global temperatures, intense storms would maintain the same frequency?


i do not believe katrina was a
once in 100 year storm
or a
once in 50 year storm

what i do believe is that the corps of eng stuffed the levees in st bernard with newspaper and just because they say they are reinforced doesn't mean it's accurate. we have levee systems all through out the usa that are in ill repair and another major event could happen anywhere. you can not always go by history as markers for future events, it just doesn't work that way.

so i decided to look at the story again after posting this and page can no longer be found

http://www.wwltv.com/local/stories/wwl042408tpleveepaper.98095b74.html
Member Since: August 11, 2008 Posts: 3 Comments: 1606
is that oil near the gulf stream the subsurface oil plume or what?
Member Since: August 27, 2008 Posts: 0 Comments: 1497
1043. Motttt
Quoting Skyepony:
The local accumet said 2 models on the oil..one had it 3 miles from the gulf stream loop, the 2nd had it already in the loop. The later matches with reports from lastnight that is was headed SW in the gulf stream. He said Keys in a few days, end of next week & it's to Cocoa Beach.

realy sad sky
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Here is an excerpt from the Internet:

"Eyjafjallajokul (pronounced ay-yah-FYAH-lah-yer-kuhl) erupted in April for the first time in nearly two centuries. During its last eruption, starting in 1821, its emissions rumbled on for two years."

Not that hard to pronounce. Lets all say Eyjafjallajokul five times really fast. Kuhl !

Has anyone started a contest on when Katla will erupt?

Member Since: Posts: Comments:
1041. Skyepony (Mod)
The local accumet said 2 models on the oil..one had it 3 miles from the gulf stream loop, the 2nd had it already in the loop. The later matches with reports from lastnight that is was headed SW in the gulf stream. He said Keys in a few days, end of next week & it's to Cocoa Beach.
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Quoting Ossqss:


How about a training video in preparation? :)

Ah, one of my favorites... lol
Member Since: October 25, 2005 Posts: 19 Comments: 22081
Hey guys, I just finished writing a blog on the 1855 Louisiana hurricane, which struck central Plaquemines Parish on September 16. This is the first in a series of blogs I will be doing pertaining to Louisiana's hurricane history from 1851 to present.

Feel free to take a look!
Member Since: March 7, 2007 Posts: 575 Comments: 20553
The Corps of Engineers reinforced the flood gates and levees in New Orleans to protect the canals against a surge during a Katrina-like storm which they call a Once-in-100-years event. They have this idea that Katrina or similar sized storm is a 100-year storm, or likely to happen only once per century.

I contend that history teaches otherwise, and that Katrina was a 50-year storm.

Hurricane Betsy made landfall on September 10th, 1965 at Grand Isle, Louisiana with a pressure of 948 mb, gusts of 160 miles per hour (mph), a forward speed of 22 mph and storm surge of 15.7 ft. New Orleans witnessed gusts of 135 mph and a 9.8 ft storm surge.

Hurricane Camille struck the Mississippi coast on August 17th, 1969 as a Category 5, with a pressure was 901 millibars and winds estimated at 175 mph. The storm surge was officially measured at 24.6 feet inside a surviving structure, but experts expect that it surpassed 28 feet.

Hurricane Katrina struck in 2005.

Can Katrina really be a Once-in-100-year event if storms of similar strength occurred 36-years and 40-years earlier? The definition of 100-year storm is based on the history of the region based on past climatology. Why would we assume that, with rising global temperatures, intense storms would maintain the same frequency?
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Things will be picking up soon Hurricane.
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Goodnight everyone.
Member Since: September 2, 2009 Posts: 130 Comments: 21193
Quoting GeoffreyWPB:


Just remember Judge Judy's Weather Book...Don't Pee On My Leg And Tell Me It's A Hurricane! :)
LOL.
Member Since: September 2, 2009 Posts: 130 Comments: 21193
Quoting MiamiHurricanes09:
Just posted a new blog. It is really in-depth of what the models are showing in the southwestern Caribbean. Feel free to comment. Enjoy!

Hurricane Season Blog #3: Models In Agreement Of Possible System Soon


Just remember Judge Judy's Weather Book...Don't Pee On My Leg And Tell Me It's A Hurricane! :)
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1033. xcool
wow haha video
Member Since: September 26, 2009 Posts: 2 Comments: 15670
1032. Ossqss
Quoting KEEPEROFTHEGATE:
nothing but ghosts and dreams


How about a training video in preparation? :)

Member Since: June 12, 2005 Posts: 6 Comments: 8186
Oh hey keeper!
Member Since: September 2, 2009 Posts: 130 Comments: 21193
Just posted a new blog. It is really in-depth of what the models are showing in the southwestern Caribbean. Feel free to comment. Enjoy!

Hurricane Season Blog #3: Models In Agreement Of Possible System Soon
Member Since: September 2, 2009 Posts: 130 Comments: 21193
1029. xcool
lmao
Member Since: September 26, 2009 Posts: 2 Comments: 15670
1028. KEEPEROFTHEGATE (Mod)
nothing but ghosts and dreams
Member Since: July 15, 2006 Posts: 171 Comments: 53787
1027. xcool
yeahh.
Member Since: September 26, 2009 Posts: 2 Comments: 15670
Quoting xcool:
Slow, ...
blog
Don't worry, once summer comes, pages will be full within 5 minutes
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Quoting xcool:
Slow, ...
blog


Nothing happening in the tropics for now...very quiet.
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1024. xcool
Slow, ...
blog
Member Since: September 26, 2009 Posts: 2 Comments: 15670
1023. KEEPEROFTHEGATE (Mod)

MODELS ARE MEANT TO BE USED AS GUIDANCE ONLY AND DONOT DEPICT FINAL OUTCOME TO ANY ONE EVENT
Member Since: July 15, 2006 Posts: 171 Comments: 53787
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1021. pottery
Had a few showers from that wave today, and heard one rumble of thunder off to my east. What is the forecast for the wind that is affecting it?
Member Since: October 24, 2005 Posts: 0 Comments: 24307

Evening folks. Too tired to post anything.
Stay safe out there. Goodnight!
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1019. aquak9
we can see the lightning from here, tho, SSI.

would rather see the rain.
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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.