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SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL

Tropical Storm Chantal

Click for full size
Shifting a bit West from earlier models
I've been tied up, (and still am), so Chantal is a bit further along than it should be for a first post. As of this morning all the models are pushing her further West than previously predicted. It's likely going to be 24 hours or more before we know if Florida is a target or not.

Also from the last 4 hours of satellite images (as of 0330 Eastern) Chantal has lost almost all of her convection and rotation looks to have fallen apart. She may have just kicked the bucket, but lets give that another update or two before we throw in the towel.

I expect that the 5AM update from the NHC will be drastically different from the 11PM.

NHC 11PM Discussion

The satellite presentation of Chantal became less organized during
the late afternoon and early evening...but there has been a burst
of deep convection recently near the estimated center. The plane
has had difficulty fixing a center...with the wind field resembling
an open wave rather than a closed circulation. However...air space
restrictions prevented the plane from sampling the area farther
south...so it is inconclusive as to whether a closed circulation
still exists. Aircraft data also suggest that some weakening has
taken place...with peak 850 mb flight-level and bias-corrected SFMR
winds of 50 and 42 kt...respectively. The initial intensity is
lowered to 50 kt for this advisory...which could be generous.

The rapid forward motion of Chantal could suggest that westerly low-
to mid-level shear is affecting the cyclone...as shown by SHIPS and
UW-CIMSS analyses. The shear should limit any additional
intensification prior to the center moving over or near Hispaniola.
Interaction with the mountainous terrain of that island should
disrupt the circulation enough to cause significant weakening or
even possibly dissipation. Whatever remains of Chantal after that
will encounter hostile upper-level westerly winds associated with a
mid- to upper-level cyclonic shear axis over the southwestern
Atlantic in about 48 hours. The GFS suggests a decoupling of the
low- to mid-level centers...while ECMWF maintains more vertical
integrity. If the cyclone survives interaction with land and
strong shear...it could regenerate or restrengthen late in the
period. It should be noted that there is significant uncertainty
in the intensity forecast in the 3 to 5 day period.

Absent reliable center fixes...the speedy initial motion estimate...
285/25...of Chantal is quite uncertain. Based on available
aircraft data the center is relocated a bit to the south relative
to the previous track...which has a resulted in southward and
westward shift of the forecast track through 36 hours. A strong
subtropical ridge guiding Chantal rapidly west-northwestward is
forecast to weaken and shift eastward as a pronounced weakness
develops along the United States East Coast and extends southward
into Florida. This should result in the track of Chantal bending
northwestward and then northward after 36 hours. The official
track forecast leans on the weaker GFS solution which has a
shallower cyclone beyond 48 hours.

Forecast positions and Max winds

init 10/0300z 15.3n 66.2w 50 kt 60 mph
12h 10/1200z 16.7n 69.3w 50 kt 60 mph
24h 11/0000z 18.6n 72.8w 40 kt 45 mph
36h 11/1200z 20.6n 75.1w 35 kt 40 mph...over land
48h 12/0000z 22.6n 76.6w 35 kt 40 mph...over water
72h 13/0000z 26.5n 78.0w 35 kt 40 mph
96h 14/0000z 29.0n 79.5w 35 kt 40 mph
120h 15/0000z 31.0n 81.0w 40 kt 45 mph


SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL

Click for full size
At 1045 PM
Click for full size
Then at 0315 AM
A couple sat shots to show the decline.. As you can see.. She just looks like a disturbance (if that) in the latter image.


SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to SmokChsr

As of 0715, Chantal is actually looking much more organized than when I last posted. Also she is moving Westward quite fast. While this one is still predicted to turn North up the East coast of Florida, it can still easily end up in the Gulf. That of course is if it holds together. Time to play the wait and see game. As weak as it is, you can't put much faith in the models.

Right now I'd say the target area is anywhere from Louisiana to North Carolina. In those areas, if you have anything you need to get done for your preps might as well get started on them. even if this one doesn't visit you'll be that far ahead for the next one.



SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to SmokChsr

Former Tropical Storm Chantal

Looks like the NHC is throwing in the towel, although convection over the area has greatly increased. Reformation is still possible. If she does reform It looks like it will be to the North of her last location. Likely on the North side of the DR. If that happens all the current track models will mean nothing, and she'll be headed up or off the East Coast.

NHC 5PM discussion..

After finding something resembling a center earlier today...the same
Air Force reconnaissance plane spent several hours investigating
the storm and determined that Chantal no longer has a closed
circulation. The data showed a very strong wind shift associated
with the axis of a wave...which is now along 73 or 74 degrees west
longitude.

The remnants are still accompanied by a large area of disturbed
weather and strong winds between 40 to 45 knots east of the wave
axis. Even though Chantal has degenerated into a wave...the threat
of heavy rains over Hispaniola will continue for another day or so.
This weather will spread westward and then northwestward over
Jamaica and eastern Cuba during the next 24 hours so. Both the
ECMWF and GFS models show the remnants of Chantal moving into
the northwestern Bahamas and near the Florida Peninsula in a couple
of days.

Global models show strong wind shear in the area of the western
Caribbean...Cuba and Florida where the remnants of Chantal are
headed. This will probably inhibit any re-development.
Nevertheless...this disturbance will continue to be closely
monitored for any signs of redevelopment...and Air Force hurricane
hunter planes are scheduled to investigate the disturbance again
during the next day or so...if necessary.

Forecast positions and Max winds

init 10/2100z 16.5n 73.7w 40 kt 45 mph...remnants of Chantal
12h 11/0600z...dissipated



SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to SmokChsr

Re: Tropical Storm Chantal

The NWS satellites haven't been properly updating on their own sites since around 10PM yesterday.. In the mean time an area of heavy convection has developed just off the Bahama's around 25N, 75W. From the limited satellite views it's darn near impossible to tell if there is any rotation underneath it. It did show quite a bit of shear just North of the area.

I'm posting this as info, so it won't be a surprise, if Chantal makes a reappearance later today.