Strong Tropical Wave WSW of CV Islands (INVEST 94L is up)

[RL3AO]

Successive GFS runs do have 355K PV becoming weaker and weaker in the Bahamas as it approaches.

The "no recurve" idea could be viable.

There does seem to be a trend of a weaker upper low.

[tailgater]

This is the 5 day forecast from Euro, GFS and CMC I couldn't get the UK met

[Nimbus]

Successive GFS runs do have 355K PV becoming weaker and weaker in the Bahamas as it approaches.

The "no recurve" idea could be viable.

There does seem to be a trend of a weaker upper low.

This is a good example of just how unsure the models are this far out.
The trend is your friend.
There is a clear weakness depicted in the Jul 1st 6Z that quickly closes off in the later runs.
If you look at the bigger picture though, the slower evolution is eroding that ridging over time.
This system isn't even an invest yet its just some models pipe dream.
Might give us some small indication of the general upper level pattern thats it.

[GCANE]

Successive GFS runs do have 355K PV becoming weaker and weaker in the Bahamas as it approaches.

The "no recurve" idea could be viable.

What exactly does that mean, I'm still learning.

PV has an effect on how a TC is steered.

355K PV represents cyclonic flow at higher altitudes.
As a TC approaches an area of higher PV each vorticity starts to spin around each other.

Here are some references that explain it better than I can.

"a tropical cyclone tends to move toward an area with a maximum in the time tendency of potential vorticity"
http://www.annualreviews.org/doi/full/1 ... 903.175702


It has been clearly established that the deep-layer mean (DLM) flow near a tropical cyclone is strongly related to its motion averaged over a 12-h period (Franklin et al. 1996; also see review in section 2a of Wu and Emanuel 1995a). Potential vorticity (PV) inversion is a powerful tool that can be applied to understanding the factors that contribute to this motion.

http://journals.ametsoc.org/doi/10.1175 ... 2.0.CO%3B2

http://www.goes-r.gov/users/comet/tropi ... _7.0.0.htm

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Sun Jul 2 2017

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Disorganized showers and thunderstorms continue in association with
a tropical wave located about 600 miles west-southwest of the Cabo
Verde Islands. Environmental conditions are expected to be conducive
for some gradual development of this system during the next several
days while it moves generally westward at about 10 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...40 percent.

$$
Forecaster Cangialosi

[GCANE]

If there really is a surface low at 10N 30W as GFS puts it, that is a really nice looking pouch with convection protecting well to its west and north.

In fact, even if its a strong wave axis, that still looks good.

[cycloneye]

Loop:

http://rammb.cira.colostate.edu/ramsdis ... display=12

[blp]

If the low is at 10n 30w it looks good. I see inflow from the north and south with good rotation. This one might spin up quickly. Any recent ASCAT images?

[RL3AO]

:uarrow: If the low is at 10n 30w it looks good. I see inflow from the north and south with good rotation. This one might spin up quickly. Any recent ASCAT images?

Nothing recent. Seems to be doing exactly what the GFS thought. Low spins up on the western edge of the monsoon trough where the westerlies are south of 10N.

[Hurricane Andrew]

I'll be surprised if this isn't tagged by the end of the day, if for no other reason than to run additional models. The picture is quite murky right now, with a wide range of possibilities sitting in the scope of probability.

The posts in this forum are NOT official forecasts 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. For official information, please refer to products from the NHC and NWS.

[weathaguyry]

Hmmm, if it continues to have decent inflow, and a little spin to it, I'd say it'll get 30/50 for the next TWO, and it'll be tagged 94L later this afternoon. Since there is no immediate threat to land, the NHC will likely take its sweet time on giving this a name. Just my amateur guess though, anything could happen

[cycloneye]

12z GFS operational is very bullish.

[Alyono]

MU and CMC are Andrewish

By that I mean, struggling in the MDR and then really cranking out of the MDR

[AutoPenalti]

12z GFS operational is very bullish.

It's been like that for a pair of runs which is vaguely scary.

[TheStormExpert]

I'd say it likely goes further up the EC or OTS.

[TheStormExpert]

12z GFS operational is very bullish.

It's been like that for a pair of runs which is vaguely scary.

While the GFS-P develops it then kills it once it reaches the NE Caribbean. It's been even more consistent then the old GFS for many runs.

[weathaguyry]

Looks a lot like 18z run yesterday from GFS OP

[RL3AO]

Lot's of uncertainty with the synoptic pattern over eastern Canada and the NE US in 10 days or so. Would make a huge impact on the storm if the GFS is right.

[weathaguyry]

OTS this run, probably as a Cat 2

[AutoPenalti]

Lot's of uncertainty with the synoptic pattern over eastern Canada and the NE US in 10 days or so. Would make a huge impact on the storm if the GFS is right.

Is that the eroding high that was being talked about that would take this OTS?