Fred fading; halfway point of hurricane season reached

By: Dr. Jeff Masters , 1:40 PM GMT on September 10, 2009

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Hurricane Fred peaked in intensity yesterday afternoon, attaining Category 3 strength with 120 mph winds. It is quite unusual to have such a powerful system so far east in the Atlantic, and Fred is only the third major hurricane to exist east of 35W. Fred is also the strongest hurricane so far south and east in the data record. However, this type of system would have been difficult to document before satellite pictures began in the 1960s.

Fred's glory is past, and the storm is on a downslide now, thanks to moderate wind shear of 15 - 20 knots and dry air eating into the hurricane's southwest side. The shear and the dry air will increase over the next few days, with the shear rising above 40 knots by Monday morning. Sea surface temperatures (SSTs) will also cool to near the 26.5°C threshold needed to sustain a tropical cyclone. The combination of high shear, dry air, and cool SSTs will likely kill Fred by Tuesday.


Figure 1. Hurricane Fred at peak strength, 8:55am EDT UTC 9/9/09. At the time, Fred was a Category 3 hurricane with 120 mph winds. Image credit: NASA.

Elsewhere in the tropics
An upper-level low pressure system has moved over Texas and is expected to spawn a surface low pressure system along the Texas Gulf of Mexico coast on Friday. This low will probably have characteristics of both a tropical and extratropical storm. The surface low is likely to move northeastward and move ashore near the Texas/Louisiana border region on Saturday or Sunday. There will be some high wind shear to the west of the low (shear is currently a high 25 knots), so it is uncertain whether this low will be capable of developing into a tropical cyclone. Regardless, this storm will bring heavy rain capable of causing flooding--and help alleviate the exceptional drought conditions over Southeast Texas.

Early next week, we should be alert for tropical storm development over the waters between the Bahamas and North Carolina, along an old frontal zone. None of the reliable models are forecasting tropical storm development in this area or in the Gulf of Mexico, though.


Figure 2. The climatological halfway point of the Atlantic hurricane season is today, September 10.

Halfway point of hurricane season
September 10 marks the halfway point of the Atlantic hurricane season. Despite a late start (Tropical Storm Ana did not form until August 15, the latest start to a hurricane season since 1992), our number of storms has been near average. An average Atlantic hurricane season has 5 named storms, 3 hurricanes, and 1 intense hurricane by the midpoint of the season. So far this year, we've had 6 named storms, 2 hurricanes, and 2 intense hurricanes. A better measure of hurricane activity that takes into account their destructive power is the Accumulated Cyclone Energy (ACE) index. ACE for an individual storm is computed by squaring the maximum sustained winds of the storm at each 6-hourly advisory, and summing up over the entire lifetime of the storm. As of 5am EDT this morning, the seasonal ACE tally was 37.5. This number should rise to around 40 by the end of the day, thanks to the presence of Hurricane Fred. Over the period 1950 - 2005, the average ACE index for a half-season was 51, so 2009 ranks about 20% below average for the halfway point of the season. But when compared to the hurricane seasons we've been having since the current active hurricane period began in 1995, this year has been quite inactive. Between 1995 and 2008, the average ACE index for the halfway point of the season was 72. Thus, 2009 is about 45% less active than what we've been accustomed to over the past 14 years.

We've been lucky this year that the steering currents have aligned to keep our two major hurricanes, Bill and Fred, out to sea. What will the rest of the season have in store for us? I'll present an analysis on Friday.

Twenty years ago on this date
On September 10, 1989, the strong tropical wave that had moved off the coast of Africa the previous day acquired an organized circulation at the surface and began building a concentrated area of heavy thunderstorms near its center. A new tropical depression, the 12th of the season, was born. Moving westward at 20 mph, the depression brought strong, gusty winds and heavy rain showers to the Cape Verdes Islands as it passed to the south. Forecasters at the National Hurricane Center predicted that the steadily organizing tropical depression would strengthen into a tropical storm within the next day or two. The next name on the list of Atlantic tropical storm names for 1989: Hugo.


Figure 3. AVHRR visible satellite image of Tropical Depression Twelve taken on September 10, 1989. Image credit: Google Earth rendition of the NOAA HURSAT data base.

Jeff Masters

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Quoting TexasHurricane:


oh,ok - sorry

channel 6

Watching Low Near Brownsville....



Low pressure is slowly becoming better organized near Brownsville this evening. This low will likely move slowly to the north-northeast and has some potential for some development. It is possible that it could become a tropical depression or tropical storm in the next 24-36 hours. The low should move inland near Freeport Saturday with widespread heavy rains spreading into our area. In fact through Sunday, rainfall totals to near 10 inches will be possible in isolated spots. With plenty of clouds, temperatures will be below normal for afternoon highs.


thanks, I try to learn on here to keep up with any storms since rita. I don't like for them to sneak up on us at all. Sometimes I know alot more from trying to learn and stay informed on this blog than I do from any news channel, of course I do appreciate all of our news channels.
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1512. hydrus
Quoting tornadodude:
Howdy guys, just thought I'd stop by for a little while, finished some more math, no problems with is tonight xD
I use to love math. Until they put a nifty page of calculus in my face...aaaarrrrgggghhhh!!!!
Member Since: September 27, 2007 Posts: 1 Comments: 22694
1510. JLPR
Quoting hydrus:
where in P.R. are you?


Carolina
Member Since: September 4, 2007 Posts: 36 Comments: 5223
1509. hydrus
Quoting JLPR:
yep Georges went right thru PR
The last one to manage that was Jeanne in 04 as a TS

I remember there was a calm in the storm, the eye, which we used to secure a shrub tree that is in our front yard since it had fallen to the right
and thanks to that it is still in my front yard today =]
where in P.R. are you?
Member Since: September 27, 2007 Posts: 1 Comments: 22694
Howdy guys, just thought I'd stop by for a little while, finished some more math, no problems with is tonight xD
Member Since: June 28, 2006 Posts: 25 Comments: 8360
1506. Seawall
Thanks for the comments from Channel 6; I can't receive them anymore since I'm east of Vidor, on the LA line.
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Quoting weatherganny:


I know,I live on the Texas/La border and I missed what they said.They are my locals too.I really would appreciate it.


oh,ok - sorry

channel 6

Watching Low Near Brownsville....



Low pressure is slowly becoming better organized near Brownsville this evening. This low will likely move slowly to the north-northeast and has some potential for some development. It is possible that it could become a tropical depression or tropical storm in the next 24-36 hours. The low should move inland near Freeport Saturday with widespread heavy rains spreading into our area. In fact through Sunday, rainfall totals to near 10 inches will be possible in isolated spots. With plenty of clouds, temperatures will be below normal for afternoon highs.

Member Since: July 2, 2009 Posts: 0 Comments: 2811
1504. hydrus
Quoting ElConando:
Shear has lowered in the Western/central GOM now as evidence by the amount of cloud cover. However shear is still imo affecting convection from forming.
Have no illusions, El-Conando, things are going to get really interesting with our tropical waters. Just my harmless opinion.
Member Since: September 27, 2007 Posts: 1 Comments: 22694
Quoting weatherganny:


Thanks so much


You're welcome.
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Quoting homelesswanderer:


Ch 6 said that it could be a tropical depression or storm, slow to develop, head this way with tons of rain.

Ch 12 doesn't think it will develop, but it could. they think we will only see 20 or 25 mph winds. Alot of rain but not as much as ch 6.


Thanks so much
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1500. hydrus
Quoting ElConando:
this the no name 1982 storm you speak of?
That is the %^**%&*!!!..It really was Quite a powerful storm. A lot of damage from surge over a large part of the coast. I feel they played this particular storm down a bit because of sloppy news reports.
Member Since: September 27, 2007 Posts: 1 Comments: 22694
Quoting jasoniscoolman09:


nvm *face palm*
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Shear has lowered in the Western/central GOM now as evidence by the amount of cloud cover. However shear is still imo affecting convection from forming.
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1496. JLPR
Quoting TexNowNM:


I liked your story. The point was it was interesting.


thank you =]

PR is very lucky, for being an island(well actually various islands) in the middle of the ocean it hasn't been visited by hurricanes for awhile
Member Since: September 4, 2007 Posts: 36 Comments: 5223
Quoting TexasHurricane:


channel 6 news and channel 12 news. Our locals...


I know,I live on the Texas/La border and I missed what they said.They are my locals too.I really would appreciate it.
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1494. hydrus
Quoting F4PHANTOM:

Alica comes to mind.Securing a split tree, as the eye passed, before it fell on the house.Standing in 4ft. of water on a ladder.
Young and dumb.
Ah yes Alicia-August of 83 if my memory still sharp. Oh, El-nino was there too. Galveston and Houston still got whacked...
Member Since: September 27, 2007 Posts: 1 Comments: 22694
Quoting weatherganny:


Could you tell me what 6 and 12 are saying must have missed that---I'd appreciate it


Ch 6 said that it could be a tropical depression or storm, slow to develop, head this way with tons of rain.

Ch 12 doesn't think it will develop, but it could. they think we will only see 20 or 25 mph winds. Alot of rain but not as much as ch 6.
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1492. Gumluvr
Quoting tornadodude:


I know exactly what you mean, I live in Indiana now (really big on basketball) but I lived in Atlanta Tx for 8 years


Hey Matt! We evacuated to Atlanta, Tx during Ike. I liked the place. We found a nice hotel that allowed our pets. They told us to call them a few days ahead of another storm and they would save us some more rooms. Ike was still blowing like crazy when he came through there. Kinda freaked me out. Hotel lost a lot of shingles. Tornado in next town tore up a bunch of houses.
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1491. Seawall
La/TX State Line here...
Rita in 05, Humberto in 07, Gustav (not bad here, but really bad around Baton Rouge), and Ike in 08.
Lots of damage from wind in Rita here where I live and job in Orange, TX, was flooded in Ike. Ike packed some winds here but nothing like Rita. I know, I stayed during both. Rita was a hell cat; you could hear the tornadoes over and above the wind. Before you ask why didn't I evacuate during Rita? It involves elderly parent who doesn't like to leave. It's hard to make the decision to stay in a major hurricane, and I don't recommend it. Ike (wind wise) was loud, but nothing like Rita. The flooding from Ike in Orange County, TX was almost ungodly from Orange to Bridge City. I spent many a youthful summer in Crystal Beach, TX, and the storm surge from Ike.. well let's say.. Crystal Beach is rebuilding a year after Ike and it will take years for that community to resemble it's old self. I now have convinced the parent it's time to leave during a major storm, and we have a major evacuation plan in place and plan on following it in the future.
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Quoting JLPR:


wasn't trying to make a point
I was just saying


I liked your story. The point was it was interesting.
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this the no name 1982 storm you speak of?
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1488. JLPR
Quoting VortMax1969:



So, what is your point?
Frances and Jenne made landfall in Florida here that year.



wasn't trying to make a point
I was just saying
Member Since: September 4, 2007 Posts: 36 Comments: 5223
Quoting KoritheMan:


Actually, I think it is "Zhorzh". It's a French name, so it's somewhat difficult to pronounce.


Yep, that's more like it.
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Quoting F4PHANTOM:

That's why I'm on this blog. To get up to date info. from models and bloggers and to interpret what I gather.


Yep. That's why I'm here as well. Found this just after Edouard came by last year. I was sure glad he didn't pull an Humberto. But there wasn't much said locally at all. Then of course I was real glad I found this before Ike.
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Joe Bastardi's Blog this eve.
Talk amongst yourselves.



THURSDAY 11 PM

HOW CAN I SLEEP WHEN I AM WATCHING WHAT I ALWAYS WANTED TO SEE AS A KID..EXCEPT I AM NOT AT HOME ( HOME TO ME WILL ALWAYS BE JERSEY.. OR RHODE ISLAND... AND WHEN THE AGGIES WIN, TEXAS A AND M)

It figures that a tropical cyclone, the first since 1903 to hit south Jersey from the southeast is a) not named and b) I am not there for it.

Lets put it this way.. while there is no solid eye, there wasnt one with Doria in 1971 on the 11 pm news as it was coming up through the Delmarva. But there sure is a vivid rotation center. And trying to tell me this should not be classified, I dont see how that can be.

It will get a score as a 2 in the impact... tropical storm conditions are occuring ( actually the worse is coming in the early morning hours and just after sunrise with this.

But here I am , wishing I was home..stuck here in the weather desert in central pa, never to see something like this again. Sure big hurricanes with better definition may come up the coast.. but from the southeast in September like this. Saying this is not warm core does not stand the smell test . It has been over warm water for 5 days now. It has a closed rotary circulation with outflow. It is producing gales. ITS MOVING NORTHWEST FOR GOODNESS SAKES. WHAT NEXT ISBELL, WITH THE CLOSED LOW THAT HAD IT WASNT TROPICAL. Of course there is a closed low to the west... how the heck can any tropical cyclone at this latitude move northwest. The 1903 storm was a hurricane, but accounts in the NYT were very dismissive of it, here is the track

http://proa.accuweather.com/adcbin/professional/storm-history.asp?storm=1903_at l_4


So let me ask you this..which is the bigger event. This, hitting from the southeast the way it is... or a recurving hurricane in the middle of nowhere

This is history.,.,even if those that are charged with recording it will not do it. We have certainly seen lesser storms with names tacked on to them in the middle of nowhere, with no way of verifying gales or the heavy rain

Think about this... just what the heck type of storm could possible do what this is doing at this time of the year on the mid atlantic coast. Its almost intuitive that it has to be tropical, and before we turned this into some agenda driven classroom, thats how it would have been classified. Pure and simple. So what you do is you trash all the tracks that came before this when you name things in the middle of nowhere without actual verification , but leave the ones that do have the same characteristics that made them tropical storms before, un named, This way you gradually rewrite history to your liking.. Its laughable.. Thunderstorms, the almighty discussion topic in developing tropical cyclones are circling west from off the water with a "non tropical" low. Simply amazing.


I guess that is the lesson.


I wish I was home, this is something I always wanted to see, and never will

Of course since it has no name... its not official, right?

ciao for now ***

THURSDAY 10 PM... WATCH THIS:

http://www.ndbc.noaa.gov/show_plot.php?station=chlv2&meas=wdpr&uom=E&time_diff= -4&time_label=EDT



Chesapeake light now has sustained winds of 49 gusting to 54!

The clear rotation center of the tropical storm is near 37 north and 74 west moving northwest about 10 mph. A turn more to th north northwest is likely by morning. Lack of recon and the kind of due diligence this deserves makes it tough to estimate what kind of wind we have, but sustained winds of 50 to 60 mph seem pretty much a good bet within 50 miles of the center on the northern and western sides.

After all we already have 49 mph

A wild night is getting wilder.

ciao for now **** THURSDAY 9 PM

SUSTAINED GALES IN VA COASTAL WATERS.

The light ship has sustained winds of 45 mph and has reported gusts over 50 mph already. Wind gusts to 45 mph have been reported over Delaware bay.

The center is at the southwest part of the major convective blow up that has developed east of the Delmarva and is rotating west. Banded rotating showers and thunderstorms can be seen off shore, but I see no eye feature yet, just a rotation center.

The track brings this to near Cape May NJ, but weakening, by noon tomorrow.

Our attention is turning to the gulf coast. While ignoring this system fully now, TPC is acknowledging the chance for development in the western gulf. The biggest threat looks to me to be a heck of alot of rain the next 5 days in southeast Texas and through the lower Miss valley, development or not. Again another system that is borderline, developing within a couple of days of impact.

Thanks for reading, ciao for now *****
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Gumluvr,

O-field is on a salt dome, thank God! Everybody, almost, got water except O-field. Some of the homes in the school district took water, and down the main road water came up from the bayou over the road, but no homes in O-field itself had water. It is pretty darn scary when you look at a map and see that area in the middle still dry, but water all around. It was weird! Mom and Dad didn't even have water get out of the banks of the drainage ditch by their house but most of the rest of the south part of the county flooded. An old survey mark (I mean old!) on my uncles land is 17 feet. That is pretty high for that part of Orange county.

According to the NOAA maps, we could get 10 feet on top of us with a cat 5 or a hurricane with a big enough wind field. That makes Kountze look reeeeealy nice!
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Quoting weatherganny:


Could you tell me what 6 and 12 are saying must have missed that---I'd appreciate it


channel 6 news and channel 12 news. Our locals...
Member Since: July 2, 2009 Posts: 0 Comments: 2811
1481. hydrus
Quoting JLPR:


I have been in a few only
but so far Georges takes the prize :P
Charley, Jeanne, David, Belle and the No name in June of 82. Those I will remember for the rest of my life.
Quoting redwagon:
I remember nobody could figure out how to pronounce 'Georges'.

I still can't. Was it 'hor-hays'?
I cannot remember either,(shorz) is all that comes to mind.
Quoting KoritheMan:


What was notable about the 82 storm? Enlighten me.
Everything was beautiful, and inside of 15 minutes it was blowing a steady 50 knots. We were anchored near Marathon in the Florida Keys. All the vessels started to drag there anchors and were head towards the coral rocks, including us. We had a 1951 Chris Craft and made of double plank mahogany (very heavy) We managed to throw the other hook in time. It was close, We would have sunk. For some reason the wind would make the strangest sound as it went around the hull. don,t know why to this day.
Member Since: September 27, 2007 Posts: 1 Comments: 22694
Dose antone see anything geting close to ny for the rest of the season
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Quoting TexasHurricane:


LOL....yeah I know. I keep thinking it is going to be a 6.....


Could you tell me what 6 and 12 are saying must have missed that---I'd appreciate it
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Quoting Gumluvr:


Yep, but hubby was asleep and missed it. Kids woke him up. Remember what I told you on how he reacts when I tell him stuff about the weather. Well, I got an instant replay on that tonight. I think I will just let him stay in the dark. Mean, I know. LOL


Lol. Had to send mine to another room to watch the football game. He did say he was a channel 12 man. :)
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We have been so lucky here in ny
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Where is that StormT kid who said there was going to be a tropical storm in the GOM by today or tomorrow?
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1474. JLPR
yep Georges went right thru PR
The last one to manage that was Jeanne in 04 as a TS

I remember there was a calm in the storm, the eye, which we used to secure a shrub tree that is in our front yard since it had fallen to the right
and thanks to that it is still in my front yard today =]
Member Since: September 4, 2007 Posts: 36 Comments: 5223
1471. Gumluvr
Quoting homelesswanderer:


Just watched the locals. On totally opposite sides of the scale of course. But yeah I wanted to comment on Carey. I remember how he was about Allison. Lol. I cringe when he says somethings not coming here. Lol. Believe it or not Greg's calling for more chance of development this time.


Yep, but hubby was asleep and missed it. Kids woke him up. Remember what I told you on how he reacts when I tell him stuff about the weather. Well, I got an instant replay on that tonight. I think I will just let him stay in the dark. Mean, I know. LOL
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Quoting F4PHANTOM:

Have the same problem in Houston. 11 says major flooding and 13 says localized heavy rain. 13 does give two scenario's though .One along the coast and one in the direction of south La.


Sounds familiar. One of says 90% the other lowered his to 70% Sat. and 50% Sun. Earlier one said would go into Freeport. The other nothing. You just have no choice but to wait and see.
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Quoting ElConando:


It is said like george with an es to the end of it. Geor-ges.


Actually, I think it is "Zhorzh". It's a French name, so it's somewhat difficult to pronounce.
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sheesh i've been complaining about the atlantic being so dry this year, but the gulf seems to finally have a bit of moisture. just a bit. For once i want a strong mid-summer trough to just clear it out but for once that is not happening.

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1467. Gumluvr
Quoting TexNowNM:
Gumluvr,

Of course I know where Kountze is. We have actually considered moving there instead of to old family homestead because Kountze is out of storm surge territory. After looking at the new Noaa storm surge maps, Kountze is looking even better.

We are north of Orangefield and south of I10, so surge is a huge concern. I guess when we do move back to Texas we will go back to the old land. I know how Patrap feels about New Orleans. Home is home.


Yeah, home is home. How bad was the surge in that area? I know most of Orange was horribly flooded but not sure about Orangefield.
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Quoting redwagon:
I remember nobody could figure out how to pronounce 'Georges'.

I still can't. Was it 'hor-hays'?


It is said like george with an es to the end of it. Geor-ges.
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Quoting laflastormtracker:


Funny quote and good, wise words. Can't wait to hang tomorrow. I hope we can just on the 13th as well. Night :)


Night. Lol. :P
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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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