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

Share this Blog
0
+

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

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 152 - 102

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23Blog Index

000
URNT10 KNHC 171626
97779 16250 11289 94200 70100 08015 64//2 /5765
RMK AF303 WXWXA 110717150241303 OB 02
;


Playing the waiting game at this point...
Member Since: Posts: Comments:
Quoting ProgressivePulse:
Adios shear




Leaning towards minimal impact in FL.
Member Since: Posts: Comments:
I think that there will be many surprises this year.

The 2011 season has been described by at least one forecaster, to go nuclear.

It's the same person who predicted that NASA would get hit in 2008, but that's all been swept nicely under the rug.
Member Since: Posts: Comments:
Quoting Grothar:


Morning PP, Seems most of the models have it moving back North at this time.





Yes but it is continuing to move south.
Member Since: Posts: Comments:
Quoting CybrTeddy:


No, defiantly not.

This is a trough split developing cyclone, which are rare in themselves. This is more of a Cristobal from 2008, a moderate-strong TS.



Defiantly?

chuckle chuckle!
Member Since: Posts: Comments:
2011 Storms
All Active Year


Atlantic
98L.INVEST

East Pacific
94E.INVEST

Central Pacific

West Pacific
08W.MA-ON

Indian Ocean

Southern Hemisphere
Member Since: Posts: Comments:
Fleet Weather Center Norfolk Tropical Feed
No Active Tropical Warnings in the Atlantic, Caribbean, or Gulf of Mexico
By Maritime.CDO@navy.mil (FWC-N CDO) from Fleet Weather Center Norfolk Virginia. Published on Sun, Jul 17, 2011.

As of Sun, 17 Jul 2011 16:30:02 GMT
Member Since: Posts: Comments:
Quoting mgdimarco:
Doesn't this appear to be a set-up for the Hurricane Andrew scenario?


No, defiantly not.

This is a trough split developing cyclone, which are rare in themselves. This is more of a Cristobal from 2008, a moderate-strong TS.
Member Since: July 8, 2005 Posts: 259 Comments: 24576
Quoting ProgressivePulse:
Morning Gro.

Large flock of Seagulls to your NNE


Sorry, NE, still got that twitch from yesterday and hit two N's


Morning PP, Seems most of the models have it moving back North at this time.



Member Since: Posts: Comments:
long range loop out of melbourne is interesting center seems to correspond well with the latest windsat
Member Since: September 11, 2010 Posts: 1 Comments: 5006
Quoting nrtiwlnvragn:



CIRA/NESDIS Experimental AMSU-A TC Intensity/Size Estimation - NOAA15

Tropical Cyclone AL982011 INVES
Current date/time: 2011 0717 1609 UTC
ATCF file date/time: 2011 0717 1200 UTC

AMSU swath date/time: 2011 0717 1444 UTC

Minimum Sea-Level Pressure: 1010 hPa
Maximum Surface Winds: 27 kt



1010 eh?
Member Since: Posts: Comments:
We have had a NW wind for the past 3 hours here in Palm Beach County, meaning a circulation center to our NE. The only time we ever have NW winds in the summer is when we have a tropical system to our NE.
Member Since: Posts: Comments:
Doesn't this appear to be a set-up for the Hurricane Andrew scenario?
Member Since: Posts: Comments:
In other news, it looks like Invest 94E may threaten Mexico in the long term.
Member Since: Posts: Comments:
Quoting ProgressivePulse:
Adios shear


Aw ish
Member Since: August 14, 2010 Posts: 10 Comments: 17823
Quoting MrstormX:
Any satellite estimates on this?



CIRA/NESDIS Experimental AMSU-A TC Intensity/Size Estimation - NOAA15

Tropical Cyclone AL982011 INVES
Current date/time: 2011 0717 1609 UTC
ATCF file date/time: 2011 0717 1200 UTC

AMSU swath date/time: 2011 0717 1444 UTC

Minimum Sea-Level Pressure: 1010 hPa
Maximum Surface Winds: 27 kt

Member Since: Posts: Comments:
When does the recon show up on google earth???
Member Since: Posts: Comments:
The NHC may be behind on the developement curve. It's happened before. "Humberto" comes to mind.
Member Since: Posts: Comments:
98L doesn't look that bad right now.Seems that I was right yesterday about the NHC bumping those odds up to 30%.Could see a 50% sometime today....
Member Since: August 14, 2010 Posts: 10 Comments: 17823
DATE/TIME LAT LON CLASSIFICATION STORM
17/1145 UTC 28.1N 79.3W T1.0/1.0 98L
Member Since: Posts: Comments:
Quoting southernbell72:
If this thing forms into anything stronger, what are the chances it will go into the gulf of mexico


It is hard to say right now. The models are all over the place.
Member Since: Posts: Comments:
Quoting AllStar17:


Although I do remember some people pointing out the possibility of this situation a couple days ago.


The funny thing is that our local mets showed this exact same senerio playing out last week. They were showing this system using what they call future track, moving South towards the Bahamas and then West towards South CFL then back to the NE somewhat. Showed it hanging around for several days turning into Weak TS. Weird how it is playing out.
Member Since: Posts: Comments:
Quoting scott39:
Higher pressures= slower developing TC.
I keep looking at the contrast with 1036.... might not a higher ridge make it easier for a higher pressure TC to get wound up?
Member Since: October 25, 2005 Posts: 19 Comments: 22734
Quoting southernbell72:
If this thing forms into anything stronger, what are the chances it will go into the gulf of mexico



Doesn't appear likely at this point.
Member Since: Posts: Comments:
Be back, Writing new blog post...
Member Since: October 3, 2010 Posts: 40 Comments: 4129
If this thing forms into anything stronger, what are the chances it will go into the gulf of mexico
Member Since: Posts: Comments:
Quoting ProgressivePulse:
Adios shear




stronger storm means a northward track..
Member Since: Posts: Comments:
Quoting CybrTeddy:
Man the curtains!
I'll be having my own blog update soon.
Think I may have to do one myself later today...
Member Since: October 25, 2005 Posts: 19 Comments: 22734
Adios shear


Member Since: Posts: Comments:
Toronto Pearson Int'l Airport
Date: 12:00 PM EDT Sunday 17 July 2011
Condition: Sunny
Pressure: 30.09 inches
Tendency: falling
Visibility: 15 miles
Air Quality Health Index: 5

Temperature: 89.2°F
Dewpoint: 62.2°F
Humidity: 41 %
Wind: W 11 gust 17 mph
Humidex: 99
Member Since: Posts: Comments:
Any satellite estimates on this?
Member Since: Posts: Comments:
Wind observations along the east coast of Florida as well as Freeport, Bahamas suggest that a circulation is certainly becoming more developed.
Member Since: Posts: Comments:
I think considering the proximity to land and the uncertainty i'd be very surprised if the NHC doesn't call this a TD shortly after recon makes it's first pass through,,,even if the cyclone doesn't meet the exact definition.
Member Since: November 7, 2009 Posts: 0 Comments: 23
98L has that snail shell look, needs to keep it up, and we have tropical depression two at the least...
Member Since: October 3, 2010 Posts: 40 Comments: 4129
Afternoon, all. I posted bunches of messages in the last blog before I realized we were at a new blog.... [I think I came in just as the blog was changing lol].... so I am reposting them from the last blog. Meanwhile I'm still playing catch-up...



Quoting BahaHurican:
Morning everybody. Hope you are enjoying your Sunday.

We got some decent rain from our current AOI yesterday. Much of the central part of New Providence was flooded due to locally heavy showers. I had a few laughs because it was obvious many drivers had forgotten how to respond to the localized flooding... And now the humidity feels more like its normal stifling self.... lol




Quoting BahaHurican:
Other feature that caught my eye this a.m. is the latest wave exiting Africa... looks like it's holding up, with some sort of associated low attached... Wouldn't that move into the WAtl some time in the next 5 days?

I'm also very interested - and concerned - to observe that Twaves moving across the basin seem to be up between 10N and 20N already, and the 1016 isobar is running along 15N as it approached the CAR.... that is a fairly fast lift in the last 10 days or so... and where do you get a 1036 high from???

Looks like some pple's implication that this may be a season of increased landfalls may be more than doomsaying.....


Quoting IKE:

"Not moving across Florida and into the GOM"........fine with me. Next.
Hey Ike. Good to see u in the blog...

Quoting hurricanehunter27:
Look's like Ma-on is finally getting rid of the dry air.
Looks like its little "sidekick" is pretty much gone, too. Guess that means the recurve towards Japan is still pretty much in play.... at most now we can hope for a slightly earlier recurve so the dirty side stays out to sea....

Quoting weathermanwannabe:


Thanks.......All we can do is wait for now although I would be a little nervous if I was in Florida/Bahamas with an organizing blob right next to the Gulf Stream just off the coast....
These ones seem to head off to the NW or NE away from us, depending on current steering. Course, looking at current analysis, this one seems set to sit there for a while....

Quoting AussieStorm:

That is looking nice, and obs or cams in Bahamas?
Not much on the north side. You should be able to get something from Grand Bahama or Abaco, if u search for either in the Wunderground weather stations section...
Quoting ProgressivePulse:
30kts reported up in the NE quad.

Also noting the westerly winds being reported from Eight Mile Rock....

Quoting Abacosurf:


http://www.rockybay.com/

elbow cay. SSW wind
Thanks, Abacosurf. I knew there was stuff out there, somewhere.... lol. Are u home to keep us up to date on what's happening in Abaco?

Member Since: October 25, 2005 Posts: 19 Comments: 22734
Member Since: Posts: Comments:
Heat index in Fargo ND is 109 with an 81 degree dewpoint
Member Since: Posts: Comments:
Quoting SLU:
It's never a good idea to say that because none of the models predict any storm development that the Atlantic is quiet and will remain so for any period of time. These models can change their output literally overnight and "surprise storms" tent to pop-up at anytime like we saw with Bonnie last year and possibly with "Bret" in 2011. Furthermore, the computer models tend not to pick up on certain disturbances until they become better organised. Never a good idea to assume things will remain quiet because the models don't pick up on anything much.



Although I do remember some people pointing out the possibility of this situation a couple days ago.
Member Since: Posts: Comments:
NHC is expecting a Cyclone for flight two. They are basically saying that if Recon doesn't find anything in the first flight the second flight will be cancelled and replaced with another invest mission tomorrow.

FLIGHT TWO -- TEAL 71
A. 18/0600
B. AFXXX 0202A CYCLONE
C. 18/0300Z
D. 29.0N 78.5W
E. 18/0500Z TO 18/0900Z
F. SFC TO 10,000 FT
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
60 percent
zoom in

POSS T.C.F.A.
XX/INV/98L
MARK
27.77N/77.77W


To me that is most certainly a developing tropical cyclone.
Member Since: Posts: Comments:
109. SLU
It's never a good idea to say that because none of the models predict any storm development that the Atlantic is quiet and will remain so for any period of time. These models can change their output literally overnight and "surprise storms" tent to pop-up at anytime like we saw with Bonnie last year and possibly with "Bret" in 2011. Furthermore, the computer models tend not to pick up on certain disturbances until they become better organised. Never a good idea to assume things will remain quiet because the models don't pick up on anything much.

Member Since: Posts: Comments:
Interesting to see what recon finds...
Member Since: Posts: Comments:
I hope that my google earth doesnt lag with the recon option like it did on Arlene.
Member Since: October 3, 2010 Posts: 40 Comments: 4129
60 percent
zoom in

POSS T.C.F.A.
XX/INV/98L
MARK
27.77N/77.77W
Member Since: Posts: Comments:
Quoting CybrTeddy:
Recon still go, what does the bold mean however?


000
NOUS42 KNHC 171615
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1215 PM EDT SUN 17 JULY 2011
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 18/1100Z TO 19/1100Z JULY 2011
TCPOD NUMBER.....11-047

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA
FLIGHT ONE -- TEAL 72
A. 18/1800Z
B. AFXXX 0302A CYCLONE
C. 18/1500Z
D. 28.0N 79.5W
E. 18/1700Z TO 18/2300Z
F. SFC TO 10,000 FT

FLIGHT TWO -- TEAL 73
A. 19/0600Z
B. AFXXX 0402A CYCLONE
C. 19/0300Z
D. 28.5N 79.5W
E. 19/0500Z TO 19/1100Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: CONTINUE 12-HRLY
FIXES WHILE SYSTEM REMAINS A THREAT.
3. REMARK: FLIGHT SCHEDULED FOR 18/1800Z WILL CONVERT TO AN
LOW-LEVEL INVEST MISSION IF THE FLIGHT SCHEDULED FOR
17/0600Z IS CANCELLED.


Just means that if they cancelled the last flight scheduled for today, that they would change the first mission tomorrow from a cyclone to a low level invest mission.
Member Since: Posts: Comments:
Quoting CybrTeddy:
Recon still go, what does the bold mean however?


000
NOUS42 KNHC 171615
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1215 PM EDT SUN 17 JULY 2011
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 18/1100Z TO 19/1100Z JULY 2011
TCPOD NUMBER.....11-047

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA
FLIGHT ONE -- TEAL 72
A. 18/1800Z
B. AFXXX 0302A CYCLONE
C. 18/1500Z
D. 28.0N 79.5W
E. 18/1700Z TO 18/2300Z
F. SFC TO 10,000 FT

FLIGHT TWO -- TEAL 73
A. 19/0600Z
B. AFXXX 0402A CYCLONE
C. 19/0300Z
D. 28.5N 79.5W
E. 19/0500Z TO 19/1100Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: CONTINUE 12-HRLY
FIXES WHILE SYSTEM REMAINS A THREAT.
3. REMARK: FLIGHT SCHEDULED FOR 18/1800Z WILL CONVERT TO AN
LOW-LEVEL INVEST MISSION IF THE FLIGHT SCHEDULED FOR
17/0600Z IS CANCELLED.




There is a typo, they must mean the second flight scheduled for 18/06Z not 17/06Z as that time is long past.
Member Since: Posts: Comments:

Complete Update

TS BUSTED FORECAST ALIBI





Member Since: Posts: Comments:
Be back later; we are going to need recon data to try and figure out where a possible coc might be trying to form; a little hard to tell at the moment for me anyway and whether it is further north or south in the disturbance.
Member Since: Posts: Comments:

Viewing: 152 - 102

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23Blog Index

Top of Page

About

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

Local Weather

Overcast
36 °F
Overcast

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron