Unusual Chantal Disorganized, but has 65 mph Winds

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

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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

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Quoting 478. ncstorm:
Hey Guys..been busy all day..

so no left turn into Florida now?





No but the overall angle is closer to FL, this may surprise NC watch out
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here comes the rain again..

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Quoting 478. ncstorm:
Hey Guys..been busy all day..

so no left turn into Florida now?


Hi NC not yet
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Wow, the plot thickens. When I briefly checked in the morning, the NHC had still shifted the cone slightly to the East and now it's shifting back to the West. What an irregular storm, pressure, wind speeds, structure, you just never know what's really going on with it.
I'll be going to bed soon and now I'm wondering what I will wake up to. Further WWD shift or back to the East? Looking at the steering patterns at the moment for weak to moderate systems, I'm not too surprised as they are more or less due west. I expect that this won't change much over night but I'm ready to put some crow onto my menu tomorrow if the erratic behaviour continues.
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Both dying
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477.

.."Charlie don't Surf !"

wait, das was a movie line me tinks..
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Quoting 475. Gearsts:
A what arrives?


Overnight hours thru Wednesday morning.
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Quoting 321. BaltimoreBrian:


Cut Off Low.

Actually in meteorological terms a col region can refer to a weakness in a ridge, or between to high pressure systems. Much like in geographical terms, the lowest point of a ridge between to peaks.
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Hey Guys..been busy all day..

so no left turn into Florida now?
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Is it possible this could pull a Charley track ?
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.."I don't know what I've been told, but convective less Tropical Storms ain't got no soul"..



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Quoting 474. Tropicsweatherpr:


So far nothing importat. Let's see when the trailing feed arrives if we get some action.
A what arrives?
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Quoting 451. Gearsts:
Not much coming


So far nothing important. Let's see when the trailing feed arrives if we get some action.
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TUTT will shear them
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Link to enlarge

As most of you will know, I'm a complete lay person, concerning weather. As most of you might know too, I like the above moisture product. First of all, because of it's nice colours :) - the curtains in my living room are coloured in a similar way. But second, as I'm watching those tropical systems for some years now, I've found it very useful to monitor whether MIMIC-TPW shows some turning in a tropical wave or not. When there isn't any, the most impressive clouds won't help much (in the moment); thus I'm not surprised there isn't a yellow crayon out for the system(s) leaving the african coast yet. On the other side I would never discount a system/wave which is still showing a decent turning, even when clouds and convection aren't very impressive in the moment. They could fire again at any moment when environment becomes more favourable.
Chantal's wave still maintains it's turning momentum until now, a little broader though. Maybe it will be disrupted by the mountains of Hispaniola, but this hasn't happened yet.
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Thank you Grothar for your SHIFT



Results for Provo, TCI (21.78N, 72.27W):
The approximate Closest Point of Approach (CPA) is located near 20.4N, 73.9W or about 140.8 miles (226.5 km) from your location. The estimated time of when the center of the storm will be at that location is in about 1 day, 13 hours and 13 minutes from now (Thursday, July 11 at 7:30AM AST).
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Quoting 462. Patrap:





Go ahead, pick a LOW,any LOW, go ahead..




notice the position the high, this is scary
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Quoting 463. Tazmanian:



i see 3 name storms line up there
Those are not TS yet.
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Quoting 459. GeoffreyWPB:

keep on shiftin W
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Chantal looks pretty ragged and fairly disorganized to me. Possible that the 65mph is based on outflow winds from earlier deeper convection?
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This morning models showed modest strengthening after Hati tonight they barley show a thing ....tomorow they may show a cat 4 at landfall, who knows
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Quoting 456. Gearsts:
OMG



i see 3 name storms line up there
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Quoting 456. Gearsts:
OMG





Go ahead, pick a LOW,any LOW, go ahead..

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Quoting 451. Gearsts:
Not much coming

not yet atleast
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no more dorian
Member Since: July 25, 2011 Posts: 0 Comments: 1102
Member Since: September 10, 2007 Posts: 0 Comments: 11453
The models dont mean anything until it tangles with the land out ahead of it. A deeper storm will feel the trough more then a weaker shallow system either a wave or a weak TS. If it is gonna be a FL even I would think a weak to mid TS at best if it is a GA/SC/NC event better chance of a stronger TS or even a minimal hurricane. Until it emerges into the SW atlantic you can throw these model runs out the window post 48 hours.
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A-Ha, I got it now!

.."Tenacious "C"....


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OMG
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Quoting 409. stormpetrol:


I have the center at 14.9N/64.1W, where do you have it?

just about the same

Quoting 412. DataNerd:
Latest windsat imagery:

Circulation appears to be undergoing reformation again.






it may be doing that

Quoting 419. stormpetrol:
I don't understand why some are talking about how disorganized Chantal looks, this is best she ever looked to me and some saying that it looks like an open wave, well I guess we're all entitled our opinion and thank goodness we all don't think alike or what a mess the world would be in!

you know
people look chantal looks good for being a TS with D-min approching it handling shear and it moving too fast it beating the odds
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1010 mb. would be like a walk in the park.

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Not much coming
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I know this is not related to the storm we have but it is weather related as far as the heat.My heart is so saddened for this family.Please keep them in your prayers.





MPD: 4-year-old found dead in car

Updated: Tuesday, 09 Jul 2013, 5:01 PM CDT
Published : Tuesday, 09 Jul 2013, 3:21 PM CDT
Candace Murphy



MOBILE COUNTY, Ala. (WALA) - Mobile police said a 4-year-old boy was found dead Tuesday afternoon, July 9 after having wandered away from home and into a hot car.

It happened at the Pine Oaks Mobile Home Park off Howells Ferry Road. Police were called to the scene around 2:15 after relatives notified them of a missing child.

A short time later, the child was found in a vehicle. Police have not released the name of the child.

Officials said the child's body will be taken to the Alabama Department of Forensic Sciences.

FOX10 News reporter Candace Murphy is on the way to the scene. You'll see her live reports on FOX10 News at 4 p.m
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Quoting 436. CaicosRetiredSailor:
This appears to forecast Chantal even a bit more to the West when it passes me...


AMZ101-100945-
SYNOPSIS FOR THE SW N ATLANTIC INCLUDING THE BAHAMAS
535 PM EDT TUE JUL 9 2013

.SYNOPSIS...RIDGE ALONG 32N WILL SHIFT S THROUGH THU THEN RETREAT
EASTWARD. TROPICAL STORM CHANTAL WILL RACE WNW ACROSS THE NE
CARIBBEAN WATERS TONIGHT AND WED...THEN WEAKEN AS IT CROSSES
HISPANIOLA WED NIGHT. THE CENTER OF TROPICAL STORM CHANTAL WILL BE
LOCATED NEAR THE WINDWARD PASSAGE EARLY THU... NEAR 22.0N 75.4W
THU AFTERNOON.
..MOVE ACROSS THE BAHAMAS TO NEAR 26.0N 77.5W FRI
AFTERNOON...THEN NORTHWARD EAST OF FLORIDA TO NEAR 28.0N 78.9W SAT
AFTERNOON AND TO 31.0N 80.0W SUN AFTERNOON.



Did it say "The Windward Passage"??
Member Since: July 17, 2009 Posts: 71 Comments: 26957
Quoting 430. Patrap:
Chantal reminds me of a Older Kid telling a younger kid to "Go Long", and pumps the ball, waves to the kid again deep, a lil Deeper and never throws da ball.


LOL
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Quoting 414. Patrap:
Miami
NEXRAD Radar

Base Reflectivity 0.50° Elevation
Range 248 NMI





DO keep a suspicious eye on that low off the tip of Florida.
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Quoting 342. MiamiHurricanes09:
Nope, he didn't do a PSA.

All of the ones in English are here:

https://www.youtube.com/playlist?list=PL63A9138A2 047B1A4
Quoting 342. MiamiHurricanes09:
Nope, he didn't do a PSA.

All of the ones in English are here:

https://www.youtube.com/playlist?list=PL63A9138A2 047B1A4
Thanks.
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Quoting 441. jeffreeysweetypie:
can we say irene?



nop
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443. HadesGodWyvern (Mod)
Category Four Typhoon Named Cyclone In Sea South Of Japan

At 21:00 PM UTC, Typhoon Soulik (935 hPa) located at 21.0N 136.5E has 10 minute sustained winds of 90 knots with gusts of 130 knots. The cyclone is reported as moving west northwest at 12 knots.

Storm Force Winds
==================
90 NM from the center

Gale Force Winds
===============
240 NM from the center

Dvorak Intensity: T5.5

Forecast and Intensity
=======================
24 HRS: 21.9N 131.4E - 105 knots (CAT 5/Intense Typhoon) South Of Japan
45 HRS: 23.0N 127.1E - 105 knots (CAT 5/Intense Typhoon) South Of Okinawa
69 HRS: 25.2N 122.2E - 100 knots (CAT 4/Very Strong Typhoon) East China Sea
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99 hrs. 1008 mb.

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Quoting 432. jeffreeysweetypie:
so you think florida will get hit?


If I was a betting man (which im not) most likely, the way its playing out. Models tend to over deepen troughs and the B.high is strong than we thought. When she exits Hispaniola we'll have a better idea. Stay prepared, and stay tuned.
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Quoting 419. stormpetrol:
I don't understand why some are talking about how disorganized Chantal looks, this is best she ever looked to me and some saying that it looks like an open wave, well I guess we're all entitled our opinion and thank goodness we all don't think alike or what a mess the world would be in!


It is odd, as she seems to be pulsing back & forth. She will look stronger & then weaker, then stronger again.
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Quoting 413. jeffreeysweetypie:
i love it when i am correct and what happened to the track that was showing this massive left turn right into central south florida come sunday? now the track shows it making a left into south carolins / georgia wow i was right on 2 days ago i knew it wouldn t hit florida


Alright, that's enough. Haven't you read anything here about the models (and potentially the NHC track) coming back West??!!

iggy-poof you go.
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This appears to forecast Chantal even a bit more to the West when it passes me...


AMZ101-100945-
SYNOPSIS FOR THE SW N ATLANTIC INCLUDING THE BAHAMAS
535 PM EDT TUE JUL 9 2013

.SYNOPSIS...RIDGE ALONG 32N WILL SHIFT S THROUGH THU THEN RETREAT
EASTWARD. TROPICAL STORM CHANTAL WILL RACE WNW ACROSS THE NE
CARIBBEAN WATERS TONIGHT AND WED...THEN WEAKEN AS IT CROSSES
HISPANIOLA WED NIGHT. THE CENTER OF TROPICAL STORM CHANTAL WILL BE
LOCATED NEAR THE WINDWARD PASSAGE EARLY THU... NEAR 22.0N 75.4W
THU AFTERNOON.
..MOVE ACROSS THE BAHAMAS TO NEAR 26.0N 77.5W FRI
AFTERNOON...THEN NORTHWARD EAST OF FLORIDA TO NEAR 28.0N 78.9W SAT
AFTERNOON AND TO 31.0N 80.0W SUN AFTERNOON.
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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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