98L may develop into a tropical depression near Florida; Ma-on a threat to Japan

By: Dr. Jeff Masters , 3:09 PM GMT on July 17, 2011

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A tropical disturbance (Invest 98L) has formed off the east coast of Florida, along the tail end of a cold front that pushed off the coast late last week. This disturbance has the potential to develop into a tropical depression that will bring heavy rains to the northern Bahamas and east coast of Florida today through Tuesday. Satellite imagery shows that the disturbance has become more organized this morning, with an expanding area of intense thunderstorms, the beginnings of a surface circulation, and upper-level outflow on the east and north sides of the storm. Some rotation of 98L is also evident on long-range radar out of Melbourne, Florida, but the rain showers are poorly organized and there is little evidence of low-level spiral banding. Wind shear is a moderate 10 - 20 knots, and sea surface temperatures are 27 - 28°C, which is plenty warm enough to support a tropical storm. There is dry, continental air over North Florida, and upper level winds out of the northwest are driving this dry air into the center of 98L, retarding development.


Figure 1. Morning satellite image of Invest 98L.

Forecast for 98L
The models are shy about developing 98L; only the HWRF model shows a tropical depression developing. The SHIPS model predicts that wind shear will be in the low to moderate range, 5 - 15 knots, over the next five days. NHC is giving 98L a 30% chance of developing into a tropical depression by Wednesday. Given the recent satellite and radar presentation of the storm, I'd put those odds higher, at 50%. A hurricane hunter aircraft is scheduled to investigate 98L this afternoon.

Steering currents are weak off the coast of Florida, and 98L can be expected to move slowly at less than 5 mph over the next two days. The HWRF and GFDL models predict 98L will execute a clockwise loop, heading towards the coast of Florida on Monday, then looping northeastwards towards South Carolina later in the week. The track of 98L will depend strongly on how intense the storm gets; a weak system is likely to stay farther to the south, while a stronger system will "feel" upper level winds with a west-to-east component, and tend to move to the northeast, parallel to the coast.

None of the reliable models predict tropical cyclone development over the remainder of the Atlantic through July 23.

U.S. heat wave to last at least another week
An unusually intense, widespread, and long-lasting heat wave over the majority of the U.S. continues to set numerous daily record highs. The latest long-range forecasts from the GFS and ECMWF models predict that the ridge of high pressure responsible for the heat wave will remain entrenched over the center or eastern portion of the country during the coming week, so the heat wave should continue for all but the Pacific Northwest through July 23. The GFS model does show that the ridge will break down some during the period 10 - 16 days from now, but such long range forecasts have low skill, and the heat wave could easily continue through the remainder of July. I'll present a more detailed look at the heat wave later this week.


Figure 2. Microwave satellite image of Typhoon Ma-on at 08:26 UTC July 17, 2011, over the West Pacific Ocean. The typhoon was undergoing an eyewall replacement cycle, with the inner eyewall collapsing and a new, larger eyewall forming from an outer spiral band. Image credit: Navy Research Lab, Monterey.

Typhoon Ma-on headed towards Japan
Powerful Category 3 Typhoon Ma-on is headed northwestward towards Japan, and is expected to brush the east coast of the main island of Honshu on Tuesday. The typhoon has weakened some over the past day, thanks to an eyewall replacement cycle where the inner eyewall collapsed, and a new, larger eyewall formed from an outer spiral band. Once this process completes, Ma-on is expected to intensify into a Category 4 storm. With water temperatures along the path of the typhoon ranging from 29 - 30°C, and wind shear expected to remain in the low to moderate range of 5 - 15 knots, Ma-on has the potential to hit Japan as a major Category 3 storm. The typhoon is unusually large, with winds of tropical storm force (39+ mph) extending out almost 350 miles to the north of the storm. A large portion of the south coast of Japan will receive tropical storm-force winds and large battering waves from Ma-on. Although the typhoon is currently a minimal Category 3 storm, its large size means that Ma-on has a tremendous amount of total kinetic energy, characteristic of a Category 5 storm. This means that Ma-on has the potential to bring a large and highly destructive storm to the coast on the right front side of where the eye makes landfall. If the eye remains just offshore, as some models are predicting, this storm surge will largely miss Japan, though.

Jeff Masters

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1052. ncstorm
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Telling by the latest vortex it's pretty safe to say that 02L is now Tropical Storm Bret. Expect an upgrade at anytime.

D. 45 kt
H. EXTRAP 1009 mb
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Quoting Hurricanes101:
USA about to lose

I hope not....
I would hope they "Win"

Taco :o)
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Quoting TomTaylor:
Are none of you watching the women's world cup, USA vs. Japan?

Incredible game on ESPN, tied 2-2, went into extra time, and now going into penalty kicks.


WOW - what a way to lose that one.
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Quoting wpb:
first fish of 2011
Can't be a fish if it gets upgraded to TS within the next 12 hrs...especially if it keeps drifting S in the process. It's only a few miles, less than 50 IIRC from the Nern end of the Little Bahama Bank....
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Quoting TomTaylor:

Penalty kicks are an incredibly lame way to end an amazing game
Agreed. Has nothing to do whatsoever with how well they play but happens all the time. Many a soccer game is won with penalty kicks.
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Japan won
Member Since: July 22, 2010 Posts: 1 Comments: 3813
Quoting TomTaylor:

Penalty kicks are incredibly lame way to end an amazing game

And an even lamer way to lose. Ah, well...

At least it was Japan, and if any country "deserves" some good news, it's that one...
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i say we have a TS at 8pm


000
URNT12 KNHC 172108
VORTEX DATA MESSAGE AL982011
A. 17/20:54:00Z
B. 27 deg 30 min N
078 deg 06 min W
C. NA
D. 45 kt
E. 041 deg 25 nm
F. 060 deg 43 kt
G. 041 deg 25 nm
H. EXTRAP 1009 mb
I. 18 C / 178 m
J. 24 C / 178 m
K. 21 C / NA
L. NA
M. NA
N. 1234 / 01
O. 0.02 / 1 nm
P. AF304 01BBA INVEST OB 16
MAX FL WIND 43 KT NE QUAD 20:45:20Z
SLP EXTRAP FROM BELOW 1500 FT



they do upgrade some times at 8pm
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Quoting beltane:
washigntonian, then JFV should already be in jail, sice he has posted many full names and addresses here. He has also sent letters threatening physical harm to many bloggers. You must not lurk that much, or for that long, or you would have seen these things.
Keeper will vouch. JFV is not a joke, he is a dangerouns sick irresponsible boy.
I didn't know that.Well then I don't feel pity on him now.
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Quoting Hurricanes101:
USA about to lose

Penalty kicks are an incredibly lame way to end an amazing game
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Quoting cchsweatherman:


Neither do I.



nop what do you see this going sure not out too sea
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Quoting FrankZapper:
I love FISH. I especially like to cook deep sea bass for all the landcasters who don't appreciate their taste. A dash of Tabasco Hot Crow Sauce completes the dish.
Lol.
Quoting Hurricanes101:


well the good news is that we will not have to see you post until the next storm
Why did I just ROTFLMFAO
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Quoting Tazmanian:
too me i this dont see it going out too sea


Neither do I.
Member Since: April 14, 2007 Posts: 8 Comments: 5030
USA about to lose
Member Since: March 10, 2010 Posts: 1 Comments: 7233
Quoting islander101010:
you'll be as famous as stormtop if it doesnt



ok
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oh well waiting for WWE chat room too start for this weekend mony in the bank
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Quoting Tazmanian:
too me i this dont see it going out too sea
you'll be as famous as stormtop if it doesnt
Member Since: September 11, 2010 Posts: 0 Comments: 4018
Quoting HarryMc:


That was a wicked nice mouse click Taz... congratulations.




thanks
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Quoting TomTaylor:
Are none of you watching the women's world cup, USA vs. Japan?

Incredible game
Nope.
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Quoting TomTaylor:
Are none of you watching the women's world cup, USA vs. Japan?

Incredible game



what dos that have too do with TD 2?
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1026. HarryMc
Quoting Tazmanian:
Quoting Guaricandilla2011:



poof


i feel better now


heh heh heh


That was a wicked nice mouse click Taz... congratulations.
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Quoting wpb:
first fish of 2011


well the good news is that we will not have to see you post until the next storm
Member Since: March 10, 2010 Posts: 1 Comments: 7233
too me i this dont see it going out too sea
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Quoting cchsweatherman:
There are some strong thunderstorms firing over and around the center of Tropical Depression 2. Based upon this, I find these solid tropical storm force winds being reported by the Hurricane Hunters quite believable. I strongly believe that we now have Tropical Storm Bret.
I'd be interested to see the reports from Marsh Harbour Abaco right now, in the midst of that strong band of storms. [which seems headed our way, so maybe I need to get on the road the way I should have been an hour ago... ]

Now, I'm kinda glad I'm not in Abaco or GB...

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Are none of you watching the women's world cup, USA vs. Japan?

Incredible game on ESPN, tied 2-2, went into extra time, and now going into penalty kicks.
Member Since: Posts: Comments:
thanks cybrted and drak...
yeah so the most accurate wind i found is 45 to 50 mph.
Member Since: October 3, 2010 Posts: 40 Comments: 4129
Quoting Guaricandilla2011:



poof


i feel better now


heh heh heh
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1019. ycd0108
The Serpent's Coil:
Good short read by Farley Mowat.
So far (i'm only half way through) it tells the story of a couple of "Fish Storm" Hurricanes in 1948: V11 in September and 1X in October, and some of the shipping involved. Few ships had functional Radar and Radio weather was also a bit spotty.
According to Mowat the North Atlantic was referred to as "the Western Sea" and an hurricane there was called a "Serpent's Coil"
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Quoting TxHurricanedude11:
Repeat This year wont be like last year eventhrough it started that way IT WONT CONTINUE...if u believe it than get some raw crow ready.


I might need to have some medium well crow with some extra hot sauce waiting around for me LOL! J/k
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1017. wpb
first fish of 2011
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Quoting beltane:
JFV, since you are so fond of posting the full names of our posters, maybe we should post YOUR full name. AND your parents full names. And your address. Let's add in the family in New York, too.

How about some information on your ill-bred offspring? You don't seem to care or support him, we don't think you'd mind.
Now that's just to extream,and people can go to Jail fot that.Okay to the weather.....
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1013. KEEPEROFTHEGATE (Mod)
Member Since: July 15, 2006 Posts: 165 Comments: 52265
Quoting beltane:
JFV, since you are so fond of posting the full names of our posters, maybe we should post YOUR full name. AND your parents full names. And your address. Let's add in the family in New York, too.

How about some information on your ill-bred offspring? You don't seem to care or support him, we don't think you'd mind.
touche
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Came back, and hooray 98L is now a TD 2.
Member Since: May 27, 2009 Posts: 0 Comments: 4355
Could see Bret sometime tonight into tomorrow morning.
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nhc does not pull any red cards
Member Since: September 11, 2010 Posts: 0 Comments: 4018
Quoting Guaricandilla2011:
Anyhow, Im off to jamar, bloggers, BBS, =).
Take your time. No hurry.
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There are some strong thunderstorms firing over and around the center of Tropical Depression 2. Based upon this, I find these solid tropical storm force winds being reported by the Hurricane Hunters quite believable. I strongly believe that we now have Tropical Storm Bret.
Member Since: April 14, 2007 Posts: 8 Comments: 5030
1009.3 mb
(~ 29.80 inHg)
Member Since: July 8, 2005 Posts: 259 Comments: 23012

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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.