Unusual Chantal Disorganized, but has 65 mph Winds

By: Dr. Jeff Masters , 8:06 PM GMT on July 09, 2013

Share this Blog
72
+

Unusual Tropical Storm Chantal has strengthened a bit more as it speeds west-northwestwards at 26 mph away from the the Lesser Antilles Islands. Sustained winds of 38 mph, gusting to 52 mph, were observed at Martinique at 10 am AST as the storm passed. However, an automated weather station at the airport measured sustained winds of 60 mph, gusting to 78 mph, according to an official with Meteo-France. The Associated Press reported that Chantal ripped the roofs off of several homes on neighboring Dominica. An Air Force hurricane hunter aircraft measured top winds at their 1,000' flight level of 89 mph at 12:55 pm AST. Top winds seen by the aircraft's SFMR instrument were about 65 mph, in a small area east of Chantal's center. The Hurricane Hunters have departed Chantal, and the next plane is due in the storm at 8 pm EDT. Chantal's winds are unusually high considering the storm's high central pressure of 1006 mb and disorganized appearance on satellite imagery. Chantal is fighting dry air associated with the Saharan Air Layer (SAL), as seen on water vapor satellite loops. This dry air is creating strong thunderstorm downdrafts that are robbing Chantal of moisture and energy. Visible satellite loops show the outflow boundaries of these thunderstorm downdrafts at the surface, spreading to the northwest of Chantal. Martinique Radar shows a large area of heavy rain that is not well-organized, lying mostly to the west of the Lesser Antilles Islands.


Figure 1. MODIS image of Chantal taken at approximately 1 pm EDT Tuesday, July 9, 2013. At the time, Chantal had top winds of 65 mph, but looked very disorganized, due to high wind shear and dry air. Dry air is creating strong thunderstorm downdrafts that are robbing Chantal of moisture and energy. Outflow boundaries from these downdrafts are spreading out to the northwest of Chantal, as seen on this satellite image. Image credit: NASA.

An small-scale easterly jet creating high shear in Chantal
Chantal is not very impressive on satellite images, with a modest amount of heavy thunderstorms that are not well-organized. Only a small amount of upper-level outflow is visible. The reason for Chantal's rather disorganized appearance can be found by looking at this morning's balloon sounding from Guadaloupe. This island was just northwest of the center of Chantal when the balloon was launched at 8 am EDT. The sounding showed typical easterly trade winds at the surface of 12 knots (14 mph.) However, the winds rose quickly aloft, with a jet of easterly winds of 35 - 53 knots between 800 - 600 mb (about 7,000 - 15,000'.) But, by the time the ballon hit 500 mb (18,000'), the winds had died down to 15 knots. A change of wind speed from 12 knots to 53 knots and back down to 15 knots from the surface to 500 mb is a tremendous amount of wind shear, which will make it very difficult for a tropical storm to keep the surface center aligned with the upper level center. The traditional measure of wind shear, the difference in wind between 200 mb and 850 mb, was 44 knots in this morning's Guadaloupe sounding, but was a much higher 56 knots from 200 mb to 700 mb. The powerful easterly wind jet was not apparent at any of the other balloon soundings this morning at adjacent islands (Barbados, Puerto Rico, Saint Martin), and demonstrates that there is a lot going on the atmosphere at small scales we cannot see which makes intensity forecasting of tropical cyclones very challenging. Thanks go to Jason Dunion of NOAA's Hurricane Research Division for pointing out this morning's interesting Guadaloupe sounding.

Forecast for Chantal
Chantal will have difficulty intensifying much more before hitting Hispaniola on Wednesday afternoon. In their 11 am EDT wind probability forecast, NHC gave Chantal a 29% chance of becoming a hurricane before hitting Hispaniola. Working against intensification will be the high wind shear from the strong mid-level easterly jet discussed above, plus the fast forward speed of the storm--tropical storms moving faster than 20 mph in the deep tropics usually have trouble intensifying. In addition, the Eastern Caribbean is an area where the trade winds accelerate, helping drive sinking air that discourages tropical storm intensification. Dry air will also slow down the intensification process. Interaction with the high mountains of Hispaniola and high wind shear may be able to destroy Chantal by Thursday. The 2 pm EDT Tuesday wind shear forecast from the SHIPS model calls for shear to rise to the high range, 20 - 35 knots, Tuesday night through Friday. On Saturday, when Chantal is expected to be in the Bahamas, moderate wind shear of 10 - 20 knots is predicted. If Chantal survives until Saturday, it will then have the opportunity to re-strengthen. The latest 12Z run of the European model (ECMWF) dissipates Chantal as it crosses Hispaniola. The 12Z run of the American GFS model has Chantal barely surviving.

Chantal's fast west-northwest forward speed of 26 mph will slow to 20 mph by Wednesday morning and then 10 mph by Thursday night, as the storm "feels" the presence of a trough of low pressure over the U.S. East Coast. This trough will steer Chantal to the northwest and then north-northwest across Hispaniola and into the Bahamas. The trough of low pressure pulling Chantal northwards is expected to lift out the the northeast over the weekend, leaving Chantal behind off the coast of Florida. High pressure will likely build in, potentially forcing Chantal westwards into the Florida or Southeast U.S. coast, with a possible Sunday landfall.

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: 2136 - 2086

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54Blog Index

Good morning, Press. And Ike. And StormJunkie (somehow just typing Junkie didn't seem quite the thing!).

While an open wave might bring a sigh of relief to some, the rain could still be copious, which Florida does NOT need at the moment. Georgia and SC don't need any more, either...
Member Since: Posts: Comments:
Quoting 2092. IKE:

Back at you. Ive had 10.16 inches of rain this month...so far.


Hey neighbor, that's about the same amount of rain I've had at my house too. Looks like good chances for rain tonight and again tomorrow. Hopefully the weekend will be nice, the 4th weekend was a washout!
Member Since: Posts: Comments:
Quoting 2131. Grothar:


Methinks the "center" (if you can call it so) is a little off
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting 2123. weatherh98:



And then turning into a hypercane skirting the entire US coastline while staying three miles off shore?!?!?


LOL, not at all, but more of a chance to re-organize into "something"
Member Since: Posts: Comments:
Quoting 2118. PanhandleChuck:
Does anyone else have a bad feeling about this wave staying South a little further West,then heading North ......... Shoot the gap between Cuba / Mexico and getting into the Gulf?


yep I'm getting to feel that could happen
Member Since: June 13, 2009 Posts: 2 Comments: 12710
2131. Grothar
Member Since: Posts: Comments:
Quoting 2057. CycloneOz:
The ULL is the key to Chantal's track. Keep an eye on it.

Nice, Oz... I liked it. I agree about the ULL... Chantal is like a girl with a crush... she keeps chasing that ULL, but it keeps pulling away... nothing like unrequited love to be a bit deflating... but she never gives up!

lol

Quoting 2077. trHUrrIXC5MMX:


Hmmm.. I see

just like crappy Emily 2011
lol... I been thinking a lot about Emily this week....

Member Since: Posts: Comments:
if you havent seen jbs free weekly clip check it out. he said the river of cooler than normal water 20n just about the warmer than normal 10n itz area is favorable for july and early august development.
Member Since: Posts: Comments:
For the first time this year,the MDR sst anomalies fall to negative. Let's see when they rebound again but between the persistent sal and strong high pressure kicking up the trade winds have cause the waters to cool.

Member Since: Posts: Comments:
Chantal now appears to be just a strong t-wave which should move more westward than computer models have indicated, but it will have to be watched when/if it gets into the NW Caribbean for possible reorganization.
Member Since: Posts: Comments:
Quoting 2112. presslord:


because there is no such place...


How about 'East Georgia' and 'South Virginia'? :)
Member Since: Posts: Comments:
Quoting 2118. PanhandleChuck:
Does anyone else have a bad feeling about this wave staying South a little further West,then heading North ......... Shoot the gap between Cuba / Mexico and getting into the Gulf?



And then turning into a hypercane skirting the entire US coastline while staying three miles off shore?!?!?
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting 2112. presslord:


because there is no such place...


So you say...



Good to see ya Chuck....And all the other old timers.
Member Since: Posts: Comments:
If you look at the RGB loop below, it does look like the storm opened up:

Link
Member Since: Posts: Comments:
Quoting 2111. StormJunkie:


Sounds like that is the case all the way through the Carolinas too.

Oh, WTH...Now Firefox is telling me I misspelled Carolinas...


What up Junkie?
Member Since: Posts: Comments:
@2113. Exactly
Member Since: Posts: Comments:
Does anyone else have a bad feeling about this wave staying South a little further West,then heading North ......... Shoot the gap between Cuba / Mexico and getting into the Gulf?
Member Since: Posts: Comments:
Quoting 2110. JrWeathermanFL:
Time: 11:37:30Z
Coordinates: 17.1667N 69.75W
Acft. Static Air Press: 970.3 mb (~ 28.65 inHg)
Acft. Geopotential Hgt: 380 meters (~ 1,247 feet)
Extrap. Sfc. Press: 1013.3 mb (~ 29.92 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 113° at 39 knots (From the ESE at ~ 44.8 mph)
Air Temp: 22.9°C (~ 73.2°F)
Dew Pt: 22.2°C (~ 72.0°F)
Peak (10s) Flt. Lvl. Wind: 40 knots (~ 46.0 mph)
SFMR Peak (10s) Sfc. Wind: 39 knots (~ 44.8 mph)
SFMR Rain Rate: 0 mm/hr (~ 0 in/hr)
(*) Denotes suspect data

Still supports 45mph right?




IF there is a Closed low
Member Since: June 17, 2011 Posts: 11 Comments: 6539
2116. HCW
The only thing that Chantal is missing is a silver pole :)

Have a great day and stay classy my friends
Member Since: Posts: Comments:
Quoting 2112. presslord:


because there is no such place...


hahahaha, good morning sir!
Member Since: Posts: Comments:
Quoting 2109. StormJunkie:


Those are anomolies. So temps may be around, slightly below normal...But still looks like warm enough water is the least of her problems. Everything over 26c from what I can tell.




Yes but the positive Atlantic tripole can increase convection across the deep tropics and prevent weaker storms in the subtropics like we have had the last few years. Just something to keep and eye on because that could make a difference.
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting 2110. JrWeathermanFL:
Time: 11:37:30Z
Coordinates: 17.1667N 69.75W
Acft. Static Air Press: 970.3 mb (~ 28.65 inHg)
Acft. Geopotential Hgt: 380 meters (~ 1,247 feet)
Extrap. Sfc. Press: 1013.3 mb (~ 29.92 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 113° at 39 knots (From the ESE at ~ 44.8 mph)
Air Temp: 22.9°C (~ 73.2°F)
Dew Pt: 22.2°C (~ 72.0°F)
Peak (10s) Flt. Lvl. Wind: 40 knots (~ 46.0 mph)
SFMR Peak (10s) Sfc. Wind: 39 knots (~ 44.8 mph)
SFMR Rain Rate: 0 mm/hr (~ 0 in/hr)
(*) Denotes suspect data

Still supports 45mph right?
surface winds yes but does she still have a center is the question?
Member Since: Posts: Comments:
Quoting 2111. StormJunkie:


Sounds like that is the case all the way through the Carolinas too.

Oh, WTH...Now Firefox is telling me I misspelled Carolinas...


because there is no such place...
Member Since: Posts: Comments:
Quoting 2106. PanhandleChuck:


Hey Ike, long time no see. We're in that ballpark of that 10" range as well. Any decent size storm that heads our way will knock down copious amounts of trees this year!


Sounds like that is the case all the way through the Carolinas too.

Oh, WTH...Now Firefox is telling me I misspelled Carolinas...
Member Since: Posts: Comments:
Time: 11:37:30Z
Coordinates: 17.1667N 69.75W
Acft. Static Air Press: 970.3 mb (~ 28.65 inHg)
Acft. Geopotential Hgt: 380 meters (~ 1,247 feet)
Extrap. Sfc. Press: 1013.3 mb (~ 29.92 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 113° at 39 knots (From the ESE at ~ 44.8 mph)
Air Temp: 22.9°C (~ 73.2°F)
Dew Pt: 22.2°C (~ 72.0°F)
Peak (10s) Flt. Lvl. Wind: 40 knots (~ 46.0 mph)
SFMR Peak (10s) Sfc. Wind: 39 knots (~ 44.8 mph)
SFMR Rain Rate: 0 mm/hr (~ 0 in/hr)
(*) Denotes suspect data

Still supports 45mph right?
Member Since: Posts: Comments:
Quoting 2105. weatherh98:
Not so ideal SST's anymore


Those are anomolies. So temps may be around, slightly below normal...But still looks like warm enough water is the least of her problems. Everything over 26c from what I can tell.

Member Since: Posts: Comments:
no one know what will happen wannebe. i would not count out either storm trackers cat 2 e.cen fl. or dingalings poof forecast. too many variables. not changing my forecast a cat 1 right up the biscayne bay
Member Since: Posts: Comments:
2107. Grothar
Confidence is low on intensity. I repeat, confidence is low.




But hot on track.

Member Since: Posts: Comments:
Quoting 2092. IKE:

Back at you. Ive had 10.16 inches of rain this month...so far.


Hey Ike, long time no see. We're in that ballpark of that 10" range as well. Any decent size storm that heads our way will knock down copious amounts of trees this year!
Member Since: Posts: Comments:
Not so ideal SST's anymore
Member Since: June 17, 2011 Posts: 11 Comments: 6539
Quoting 2100. Grothar:


That... would be a nightmare... :(
Member Since: Posts: Comments:
Good Morning. My best friend from Miami, who has been through several hurricanes including Andrew, texted me last night with the following message; "Storm is going to be a non-event here".

Helped keep me in perspective.......A small compact marginal TS is pretty much a non-event. It's land falling eye walls that we really need to worry about in the big scheme of things.
Member Since: Posts: Comments:
Quoting 2032. jeffreeysweetypie:
stop it
Hi, sweety, I see Chantal is coming for a visit.... lol.... maybe... quite different from an "out to sea" scenario...

Seriously, I didn't buy the eastern tracks because they unrealistically sent Chantal into the middle of that high, which has not budged for weeks, without any indication of what would create a weakness there. The over-my-head track made more sense because of the ULL, but I am not surprised to see that the trough that was supposed to pull Chantal is just going over the high instead of cutting deeply and it pushing back.

So enjoy, sweety... Chantal is a drama-queen, and just when she looks down and out, makeup smeared and everything, she may be plotting a comeback... lol
Member Since: Posts: Comments:
ASCAT pass says no closed circulation
OSCAT pass says no closed circulation
If recon goes in and finds only a wave structure the NHC has no choice...
Member Since: June 17, 2011 Posts: 11 Comments: 6539
2100. Grothar
Member Since: Posts: Comments:
I'd guess her center is closer to the northern ball of convection. Near the hot towers. But that is a guess at best...



but if it is near there, it is about to enter some very, very harsh terrain.
Member Since: Posts: Comments:
2098. ncstorm
Good Morning Everyone..

The Euro is taking remnants of Chantal right into NC..





Member Since: Posts: Comments:
Quoting 2088. islander101010:
might be an open wave but shes so vigorous she:ll be a cyclone again as soon a she turns nw


If, and only if she can survive any mountain interaction...Tough terrain for any storm; much less a weak system.
Member Since: Posts: Comments:
2096. IKE

Quoting BahaHurican:
Hey, Ike... looks like 2013 is not going to be another quiet July... :o)
Agree.
Member Since: Posts: Comments:
2095. emguy
Quoting 2079. StormJunkie:
Will need a few frames to really tell what she's up to.



If I placed a best guess on where she's at...she has a swirl....maybe a remanant type above the surface...that is just west of that southweternmost thunderstorm complex. Thunderstorm are indeed going up, but they are lagging her right now. It's the westerly shear that is going to be the big fight for now.
Member Since: Posts: Comments:
Hey, Ike... looks like 2013 is not going to be another quiet July... :o)
Member Since: Posts: Comments:
Quoting 2025. jeffreeysweetypie:
there will be at least 10 more different landfall tracks over the next 3 days and it wont even be a wave by then
And?
So?
I'd be very happy to see Chantal bypass Haiti. Cuba and FL and the NW Bahamas can stand a hit by a low-end TS or a vigorous open wave. There are hundreds of thousands of Haitians who would be spared the misery such a "wimpy" storm would bring.

However, ymmv....
Member Since: Posts: Comments:
2092. IKE

Quoting KEEPEROFTHEGATE:
nice to see ya ike
Back at you. Ive had 10.16 inches of rain this month...so far.
Member Since: Posts: Comments:
2091. RTLSNK
Member Since: Posts: Comments:
2090. Grothar
Looks like it is going to skirt Hispaniola. If the weakness in the ridge moves in it could turn earlier and then begin moving back west.


Member Since: Posts: Comments:
Quoting 2086. gator23:
oh. Is that where you live? Do you want this storm? I find that people's forecast track is often influenced by where they live. It just doesnt seem likely has Texas would be a 1000 plus mile swing which usually never happens


No I live further up the coast. Its a prediction I made and i'm sticking with it. If i'm wrong i'm wrong! I believe this will take a westward track rather than northerly at this point.
Member Since: September 2, 2011 Posts: 0 Comments: 1149
might be an open wave but shes so vigorous she:ll be a cyclone again as soon a she turns nw
Member Since: Posts: Comments:
Quoting 2065. KORBIN:
Up the west coast of Florida on a similar path would be much scarier if she developed. Since the majority of a storms strength is in the NE Quad.


how can you be able to divide this storm into quadrants...?? this best applies to strong and well developed hurricanes
Member Since: Posts: Comments:
2086. gator23
oh. Is that where you live? Do you want this storm? I find that people's forecast track is often influenced by where they live. It just doesnt seem likely has Texas would be a 1000 plus mile swing which usually never happens

Quoting 2075. Stormchaser121:

Well...I do mean Texas.
Member Since: Posts: Comments:

Viewing: 2136 - 2086

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54Blog 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
29 °F
Overcast