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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WEEEEEEEEEEEEL I am off to bed soon, I just wanted to say that

A. I am definetly going to find a Japanese Translation Site for making fun of Typhoon Names Accuratly
B. I am going to link my "Dust Bowl Complaints
C. I am Going to Stop capitalizing words so Often starting NOW|
D. I will not stop talking about Thunderstorms and Tornadoes like they are people...... hi Fred!
E. I am going to stop writing at 12:40 a.m. in the morning whrn I have to get up at 9! Probably 11p.m.
F. I am going to stop BROADCASTING MY THOUGHT ON THE BLOG COMMENT SECTION!!

And thats my pledge to stop "comment warming".

By the way, wind shear is hurting ALL cyclones bad, we have only had 2 Hurricanes out of 7 cyclones! One was a depression.
Member Since: Posts: Comments:
1712. hydrus
Quoting F5Tornado:
Im embarrased
About what?
Member Since: September 27, 2007 Posts: 1 Comments: 19497
Im embarrased
Member Since: Posts: Comments:
1710. hydrus
Quoting VEROBEACHFL1:
someone probably already answered you but in reality "longwang" for the chinese meant "dragon king", kinda like the u.s. equivelent to jim morrison as "the lizard king" --- or something like that........
I stand corrected, I said it was Dragon tail .
Member Since: September 27, 2007 Posts: 1 Comments: 19497
Couldn't sleep. Well it's not much but this finally updated.

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT FRI SEP 11 2009

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

WEAK PRES PATTERN ACROSS THE GULF OF MEXICO WITH A 1011 MB
SURFACE LOW JUST S OF BROWNSVILLE TEXAS. THE LOW IS FORECAST
TO MOVE TO THE NNE. SLY WINDS PICK UP ACROSS THE NORTHERN GULF
OVER THE WEEKEND AS A WEAK COLD FRONT APPROACHES THE TEXAS COAST
THE FRONT WILL MOVE OFFSHORE INTO THE NW GULF ON MON AND
EXTEND FROM SE LOUISIANA TO S TEXAS ON TUE.

So if there is actually a surface low there already then. Maye we'll have something to track instead of guess if it will exist. Lol.
Member Since: August 15, 2008 Posts: 10 Comments: 3665
1708. hydrus
Quoting JLPR:
Hello Fred

Blackout is over and im off to bed xD
goodnight
Adios.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1707. hydrus
Quoting Gumluvr:


Yeah, not much info for the first year it was used. Now, the second in 2005, the name is funny but not the fatalities. :( Hope, I didn't offend anyone. They really need to change there naming system but the names probably mean something totally different to them.
I know ,storm names was the issue and it lead inevitably to the dreaded typhoon Longwang-(which means dragon king in Chinese).
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1706. JLPR
Hello Fred

Blackout is over and im off to bed xD
goodnight
Member Since: Posts: Comments:
someone probably already answered you but in reality "longwang" for the chinese meant "dragon king", kinda like the u.s. equivelent to jim morrison as "the lizard king" --- or something like that........
Member Since: Posts: Comments:
Quoting Gumluvr:


Yeah, not much info for the first year it was used. Now, the second in 2005, the name is funny but not the fatalities. :( Hope, I didn't offend anyone. They really need to change there naming system but the names probably mean something totally different to them.


I made fun of more names then you could possibly imagine.
Member Since: Posts: Comments:
Quoting Gumluvr:


We can all breathe a sigh of relief when it does. Hopefully, the gulf won't be able to produce anything more than a TS this season. Don't worry about the spelling. LOL It is late for us. You do live near my area, correct?? TexNowNM emailed me and said she you were. I live North of Beaumont.


Nope, guess again, somewhere in the Dust Bowl.... Drum Roll please.... (I hate the dustbowl)

UTAH!!!! The site for the most boring weather on earth, and I am a severe weather enthusiast! Figures that I love severe weather and I just hate how thunderstorms come in, hit the rockies and

A. The low pressure system breaks apart and so does the thunderstorm
B. Just before hitting, the thunderstorm dissapates
C.The Salt Lake Splits the thudnerstorm in to halves, and the cirrus trails are the 'only thing that hits us.

Other things like, the other month, A cold front with rotation came 9in at almost the right time. And guess what was missing? MOISTURE!!! And what happened after the cold front passed??? MOSITURE CAME!! And raced the Cold front over Oklahoma!
Member Since: Posts: Comments:
1702. hydrus
Quoting HIEXPRESS:
BYX
Thank you very much , it is the place of my birth..MMEEEAAMMEEE! Oh, thats Key West.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1701. Gumluvr
Quoting hydrus:
Did you look it up?


Yeah, not much info for the first year it was used. Now, the second in 2005, the name is funny but not the fatalities. :( Hope, I didn't offend anyone. They really need to change there naming system but the names probably mean something totally different to them.
Member Since: Posts: Comments:
1700. hydrus
Quoting HIEXPRESS:
BYX
I do not comprehend BYX..Please elaborate futher on radar situation.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
BYX
Member Since: Posts: Comments:
1698. hydrus
Quoting hydrus:
were is that radar out of?
It looks like the Fl Straits.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1697. hydrus
Quoting VEROBEACHFL1:
oh yeah, Typhoon Longwang 2005, well, he eventually "petered out" lmao...........
you get an A for wit sharp enough to shave with. ..that was good.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1696. hydrus
Quoting JLPR:


yep I laughed =P but the Typhoon was a strong one
plus the name has been used twice lol
in 2000 and in 2005
The 2005 Longwang from Wikipedia
Cool, I am glad you saw it, I have a witness.lol.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
oh yeah, Typhoon Longwang 2005, well, he eventually "petered out" lmao...........
Member Since: Posts: Comments:
1694. hydrus
Quoting HIEXPRESS:
Remnants of Erika
Pinhole eye (dreaded)?
BYX
were is that radar out of?
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1693. JLPR
Quoting hydrus:
You think that is stupid, Google typhoon Longwang (this is not a joke) and return here and tell me if you laughed.


yep I laughed =P but the Typhoon was a strong one
plus the name has been used twice lol
in 2000 and in 2005
The 2005 Longwang from Wikipedia
Member Since: Posts: Comments:
Remnants of Erika
Pinhole eye (dreaded)?
BYX
Member Since: Posts: Comments:
1691. hydrus
Quoting Gumluvr:


That is too funny for words. LMBO
Did you look it up?
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1690. Gumluvr
Quoting hydrus:
I am saying to you that name has already been used for a typhoon.


That is too funny for words. LMBO
Member Since: Posts: Comments:
1689. hydrus
Quoting F5Tornado:


Not a suprise if it is, the names go from things that seem to refer to "Typhoon Kwan Kwo Do" to "Typhoon Mushroom Soup!"
If I only knew how to link I would show it to you, Its worth a look. I have to learn more about these computers. My Tandy 64K was a lot different than the new ones of today.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1688. Gumluvr
Quoting F5Tornado:
Goodbye Fred..... Shear tendency increasing highly, there is an extremly remote chance of SUSTANABILITY in my opinion (Sorry for the bad spellink.... Lahing Ot Louoood)the SSTs, wind shear, and lower moisture are killing the hurricane. R.I.A. Fred


We can all breathe a sigh of relief when it does. Hopefully, the gulf won't be able to produce anything more than a TS this season. Don't worry about the spelling. LOL It is late for us. You do live near my area, correct?? TexNowNM emailed me and said she you were. I live North of Beaumont.
Member Since: Posts: Comments:
Quoting hydrus:
I am saying to you that name has already been used for a typhoon.


Not a suprise if it is, the names go from things that seem to refer to "Typhoon Kwan Kwo Do" to "Typhoon Mushroom Soup!"
Member Since: Posts: Comments:
1686. hydrus
Quoting F5Tornado:


Typhoon Whaaaa? (That probably will be a name) " Major Typhoon Whaaaa kills thousands due to excess laughter because or the Nationwide Broadcast, the citizens only took action after the power to the T.V. was cut, however hundreds may have died BECAUSE of laughing. In other news....."
I am saying to you that name has already been used for a typhoon.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
Goodbye Fred..... Shear tendency increasing highly, there is an extremly remote chance of SUSTANABILITY in my opinion (Sorry for the bad spellink.... Lahing Ot Louoood)the SSTs, wind shear, and lower moisture are killing the hurricane. R.I.A. Fred
Member Since: Posts: Comments:
1684. hydrus
Quoting Gumluvr:


I am still learning. I remember Storm talking about this and believe your correct. Some of the models are showing several vortexes in the gulf. If the shear map that I am looking at is correct, then the gulf may have a few surprises in store. Just my(still trying to get my learner's weather permit)opinion. LOL
Real quickly, the MJO or the Madden-Julian Oscillation, is the upward or downward motion of the atmosphere. Up or lifting air promotes development while sinking air precludes development.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
My public advisory on Mujigae at 11PM
Member Since: Posts: Comments:
Quoting hydrus:
You think that is stupid, Google typhoon Longwang (this is not a joke) and return here and tell me if you laughed.


Typhoon Whaaaa? (That probably will be a name) " Major Typhoon Whaaaa kills thousands due to excess laughter because or the Nationwide Broadcast, the citizens only took action after the power to the T.V. was cut, however hundreds may have died BECAUSE of laughing. In other news....."
Member Since: Posts: Comments:
1681. Gumluvr
Quoting hydrus:
The MJO is returning, this is going to change a couple of things.


I am still learning. I remember Storm talking about this and believe your correct. Some of the models are showing several vortexes in the gulf. If the shear map that I am looking at is correct, then the gulf may have a few surprises in store. Just my(still trying to get my learner's weather permit)opinion. LOL
Member Since: Posts: Comments:
1680. hydrus
Quoting JLPR:


although it looks more like a TS than a Hurricane
No question, Fred is taking a beating.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1679. hydrus
Quoting JLPR:
I cant believe Fred is still looking this good with all the shear

Eumetsat

since we are at Blackout :|
Did you read my post #1640?
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1678. JLPR


although it looks more like a TS than a Hurricane
Member Since: Posts: Comments:
1677. hydrus
Quoting F5Tornado:
I have tyo go in 30 min. and I have not visited in a while, but I did want to say that Fread in colliding iwht a whole lot of wind shear, and here is the link to it incase your interested:
Link

I think that thats why Fred is going to die really quicky. Your opinion counts...
Fred will hang in there longer than anticipated and surprise us. just my harmless opinion.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1676. JLPR
I cant believe Fred is still looking this good with all the shear

Eumetsat

since we are at Blackout :|
Member Since: Posts: Comments:
1675. hydrus
Quoting F5Tornado:


You kidding? Fifi? Thousands killed... that makes me almost vomit too. But even worse is that Japan will start naming Tropical Typhoons after pets, foods, and more "colorful names" Imagine "Hurricane Chowder" Or "Hurricane Shrimp"

Now thats stupid!
You think that is stupid, Google typhoon Longwang (this is not a joke) and return here and tell me if you laughed.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1674. hydrus
Quoting Gumluvr:


Our local wx guy said the gulf will be open soon. He is talking about the high that we have had protecting us this season. I am not a wishcaster, either. Just have to wait and see.
The MJO is returning, this is going to change a couple of things.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
Quoting hydrus:
If you want to read something semi-funny, read post#1640.


You kidding? Fifi? Thousands killed... that makes me almost vomit too. But even worse is that Japan will start naming Tropical Typhoons after pets, foods, and more "colorful names" Imagine "Hurricane Chowder" Or "Hurricane Shrimp"

Now thats stupid!
Member Since: Posts: Comments:
1672. Gumluvr
Quoting hydrus:
I had gummies once, I did not like them, but I never really had a sweet tooth any way... I believe we will have some action in the gulf worthy of some kind of watches within the next 36 hours. I am not wishcasting.


Our local wx guy said the gulf will be open soon. He is talking about the high that we have had protecting us this season. I am not a wishcaster, either. Just have to wait and see.
Member Since: Posts: Comments:
I have tyo go in 30 min. and I have not visited in a while, but I did want to say that Fread in colliding iwht a whole lot of wind shear, and here is the link to it incase your interested:
Link

I think that thats why Fred is going to die really quicky. Your opinion counts...
Member Since: Posts: Comments:
1670. centex
I've been given special wishcasting privileges because of drought. I've tried to use them wisely as not to waste. While I would like the GOM low to move inland and stall before moving NE, I'm not counting on that. Just abundance of tropical moisture with slow moving front and associated low is just fine. We take it any way we can get it.
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1669. Gumluvr
Quoting homelesswanderer:
Ah memories. Looking at all that reminds me that I agree with Ritarefugee's assessment of that Storm. Lol. Well good night yall. I'll never make it to the ECMWF run. See yall tomorrow. :)


If your still here, then goodnight to you, Tex and TexNowNM. I might stay up a little while longer.
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1668. hydrus
Quoting jeffs713:

Its true!

And for a more PG version, you can also use gummi bears. Just get them wet, and throw them at a smooth wall. Some will stick, some won't. (most won't, and would therefore be wasted, which makes gummi bear addicts like me sad)
If you want to read something semi-funny, read post#1640.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
1667. hydrus
Quoting jeffs713:

Its true!

And for a more PG version, you can also use gummi bears. Just get them wet, and throw them at a smooth wall. Some will stick, some won't. (most won't, and would therefore be wasted, which makes gummi bear addicts like me sad)
I had gummies once, I did not like them, but I never really had a sweet tooth any way... I believe we will have some action in the gulf worthy of some kind of watches within the next 36 hours. I am not wishcasting.
Member Since: September 27, 2007 Posts: 1 Comments: 19497
Ah memories. Looking at all that reminds me that I agree with Ritarefugee's assessment of that Storm. Lol. Well good night yall. I'll never make it to the ECMWF run. See yall tomorrow. :)
Member Since: August 15, 2008 Posts: 10 Comments: 3665
1665. 2ifbyC
Quoting TexNowNM:
There weren't any cows or horses back there, but where ever you walked, there were fleas.


It's tough being the only 'food source' in the neighborhood!
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Quoting hydrus:
Jeffs713-I have to say to you, that comment about the crap sticking to the wall, fricken hilarious .

Its true!

And for a more PG version, you can also use gummi bears. Just get them wet, and throw them at a smooth wall. Some will stick, some won't. (most won't, and would therefore be wasted, which makes gummi bear addicts like me sad)
Member Since: August 3, 2008 Posts: 16 Comments: 5792
Quoting hydrus:
What were the peak gusts in your location ? if that data even exists...


I don't know where Cad is from but here's a sense of Ritas wind field. Although I am not too sure she didn't have hurricane winds farther. But heres what they say.

Member Since: August 15, 2008 Posts: 10 Comments: 3665

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About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.