ATL: GRACE - Renmants - Discussion

[Nimbus]

Grace is a boring little tropical storm making a bee line for the Caribbean.
Shear has been very strong this year south of the islands so unless Grace finds some favorable conditions west of 50 there is not much we can speculate about.

[Sanibel]

2015 syndrome plain and simple. Not even a burst period like Danny.

[TJRE]

http://tropic.ssec.wisc.edu/real-time/m ... npage.html

tracking is what we do... regardless

OPC at 96hrs



http://www.opc.ncep.noaa.gov/Atl_tab.shtml

[Hammy]

2015 syndrome plain and simple. Not even a burst period like Danny.

Danny had much more favorable conditions too. NHC from the time this formed indicated it would be running into dry air in a few days. I'm not sure why anyone expected this to get any stronger than it did.



Would this be the cause of the Atlantic drying back up over the last few days?

[ConvergenceZone]

Conditions wise, 2015 is exactly what was predicted for 2015, so we shouldn't be surprised....

[Ntxw]

2015 syndrome plain and simple. Not even a burst period like Danny.

Danny had much more favorable conditions too. NHC from the time this formed indicated it would be running into dry air in a few days. I'm not sure why anyone expected this to get any stronger than it did.

http://i.imgur.com/LcQrugX.png

Would this be the cause of the Atlantic drying back up over the last few days?

I think that's a good assessment. Though Danny didn't have the best environment, shear wasn't as high over him and he moved slow. The passing CCKW (rising air) over him helped at first and he was able to build thunderstorms and keep them around his center. When shear really lowered he took advantage.

[cycloneye]

Is still TS Grace but.....

TROPICAL STORM GRACE DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072015
500 PM AST MON SEP 07 2015

Deep convection associated with Grace has been waning today, and
banding features are not evident. In fact, if the convection does
not make a comeback soon, the system will be too weak to classify
using the Dvorak technique. The current intensity is held at 40
kt, mainly based on the winds from an earlier ASCAT overpass.
Westerly shear on Grace is forecast to increase over the next
couple of days, but assuming that the convection will make at least
a little comeback, the system is forecast to maintain tropical storm
intensity for a day or two. This is consistent with the latest
intensity model consensus. The new NHC intensity forecast shows a
much sooner degeneration to a remnant low, compared to the previous
advisory. Clearly, Grace could dissipate much sooner than shown
here.

The storm continues its rapid westward motion, even a little faster
than earlier. A low- to mid-level ridge to the north of Grace
should maintain a swift motion toward the west or slightly north of
west over the next few days. The official track forecast remains
close to the latest dynamical model consensus. This is not quite
as fast as the ECMWF, but that model opens the system up into a
wave within 48 hours.

The 34-kt wind radii have been modified, based on earlier
scatterometer data that showed a lack of winds to tropical storm
force over the southern semicircle of the cyclone.

FORECAST POSITIONS AND MAX WINDS

INIT 07/2100Z 14.0N 37.5W 40 KT 45 MPH
12H 08/0600Z 14.1N 40.0W 40 KT 45 MPH
24H 08/1800Z 14.3N 43.3W 35 KT 40 MPH
36H 09/0600Z 14.7N 46.5W 35 KT 40 MPH
48H 09/1800Z 15.2N 50.0W 30 KT 35 MPH
72H 10/1800Z 16.0N 57.0W 25 KT 30 MPH...POST-TROPICAL
96H 11/1800Z...DISSIPATED

$$
Forecaster Pasch

[floridasun78]

GRACE other . El Niño storm came and want look like eastern Atlantic only place support system near Africa

[emeraldislenc]

Grace does not look to Amazing.

[ConvergenceZone]

at least with Grace, it's almost a 100% certainty that it's going to eventually open up into a wave. With the others, it was not near as evident.........





Disclaimer
---------------------------------------------------------------------------------------------------------------------------------------------------
The above post is not official and should not be used as a official prediction. It is the opinion of myself and may or may not be backed by sound meteorological data. For official information, please refer to the NHC and NWS products.

[abajan]

Grace does not look to Amazing.

She looks disgraceful

[emeraldislenc]

I know it was a play on words "Amazing Grace"

[Hurricaneman]

Grace looks like its on its last legs due to 20+kts of shear and sinking air

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[Hammy]

I honestly doubt this will survive another day, it doesn't even look like a tropical system at this point. It's literally being squashed by the subsidence.

[blp]

Nice blow-up right now over the center. It really needs this to stay alive.


http://www.ssd.noaa.gov/PS/TROP/floater ... imated.gif

[gatorcane]

Yep quite a burst of convection right over the center and I don't see it getting sheared off either.

The RAMMB floater is a bit ahead of the NHC floater (by one frame technically) and the convection continues to expand as of 01:45 UTC. Link below:
http://rammb.cira.colostate.edu/ramsdis ... display=12

[blp]

Looking at the shear maps it looks to be passing the worst of the immediate shear that was affecting it earlier and now looks to be entering the 15 to 10 knot shear zone. I think it should regain some strength over the next couple of days before getting hit with major shear over the Carribean.

[cycloneye]

TROPICAL STORM GRACE DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072015
1100 PM AST MON SEP 07 2015

After being devoid of any significant convection near the center for
almost 6 hours, a small burst of deep convection with cloud tops
colder than -80 deg C has developed since 0000 UTC just south of and
over the previously exposed low-level circulation center. This
recent convective development is the reason for keeping Grace as a
35-kt tropical storm. This intensity is supported by a Dvorak
current intensity estimate of T2.5/35 kt from TAFB and a couple of
32-kt ASCAT-B wind vectors.

The initial motion estimate is 275/17 kt. There is essentially no
change to the previous forecast reasonings over the past couple of
days. Grace is expected to gradually weaken and become more
vertically shallow, and be steered quickly westward by the moderate
low-level easterly trade wind flow on the south side of a deep-layer
ridge. The official track forecast is just an update and extension
of the previous advisory track, and lies close to the dynamical
model consensus, TVCA.

With increasing southwesterly to westerly vertical wind shear and an
abundance of dry mid-level air ahead of Grace, steady weakening is
expected due to these hostile environmental conditions. The only
saving grace is the cyclone's robust low-level circulation, which
could force periodic bursts of deep convection for the next 24 hours
or so, similar to the most recent convective development. However,
by 36 hours and beyond, westerly shear in excess of 25 kt should
cause the circulation to weaken significantly due to less frequent
and shorter duration convective bursts. Degeneration into a remnant
low is expected by 48 hours, followed by dissipation in 96 hours.
However, dissipation could occur sooner, similar to the ECMWF model
solution. The new NHC intensity forecast closely follows the IVCN
consensus model.

FORECAST POSITIONS AND MAX WINDS

INIT 08/0300Z 14.0N 39.2W 35 KT 40 MPH
12H 08/1200Z 14.1N 41.8W 35 KT 40 MPH
24H 09/0000Z 14.3N 45.1W 30 KT 35 MPH
36H 09/1200Z 14.7N 48.4W 30 KT 35 MPH
48H 10/0000Z 15.1N 51.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 11/0000Z 16.0N 58.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 12/0000Z...DISSIPATED

$$
Forecaster Stewart

[fendie]

TROPICAL STORM GRACE DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072015
1100 PM AST MON SEP 07 2015

...

The only saving grace is the cyclone's robust low-level circulation, which
could force periodic bursts of deep convection for the next 24 hours
or so similar to the most recent convective development.

...

$$
Forecaster Stewart

Glad to see the NHC jumping on the play-on-words bandwagon. Of course, most don't believe there's any 'saving grace.'

[emeraldislenc]

Good play on words saving grace