2021 Tropical Waves Thread

[Aric Dunn]

Today will be the day. If it can hold convection and wrangle together the broken pieces of the ITCZ then it should develop at some point over the next 48 hours.

[Aric Dunn]

Becoming more defined. From 1:30 AM 5 hours ago

[StPeteMike]

The consecutive runs showing a storm forming around the 29th will likely pan out. We saw the same with Claudette, be it many runs had a stronger system than what came to be. But we should definitely watch this one a week from now.

[Aric Dunn]

up to 20/20


000
ABNT20 KNHC 211111
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Mon Jun 21 2021

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

The National Hurricane Center is issuing advisories on recently
upgraded Tropical Storm Claudette, located inland over northeastern
North Carolina.

A well-defined tropical wave located about 900 miles east-southeast
of the Windward Islands is producing disorganized showers and
thunderstorms. Some development of this disturbance will be possible
during the next couple of days before upper-level winds become less
conducive for further organization by Thursday. The system is
expected to move westward to west-northwestward at around 15 mph.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.

$$
Forecaster Stewart

[tolakram]

SLIDER
https://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=16092.693359375&y=8781.29248046875&z=3&angle=0&im=12&ts=1&st=0&et=0&speed=130&motion=loop&maps%5Bborders%5D=white&lat=0&p%5B0%5D=band_02&opacity%5B0%5D=1&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&draw_color=FFD700&draw_width=6

[tolakram]

[AutoPenalti]

Looks like it's getting its act together real quick.

[Aric Dunn]

Will this be the catalyst for WCarr development that the Euro and GFS keep developing?

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

[abajan]

Will this be the catalyst for WCarr development that the Euro and GFS keep developing?

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

Aric, I find these systems tend to accelerate as they approach the Lesser Antilles. According to the latest TWO, it's moving at about 15 mph. Do you think its forward speed will increase, decrease, or remain pretty much the same as it moves westward?

[Aric Dunn]

Will this be the catalyst for WCarr development that the Euro and GFS keep developing?

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

Aric, I find these systems tend to accelerate as they approach the Lesser Antilles. According to the latest TWO, it's moving at about 15 mph. Do you think its forward speed will increase, decrease, or remain pretty much the same as it moves westward?

Well they definitely speed up once they reach the eastern Carrib. They can accelerate before the islands if the ridge builds in stronger. So far from the models the ridge stays pretty much the same and the models don't really speed it up. the wave does become more amplified as it approaches the islands which is normal.... but the shear also increases at that time.

[AnnularCane]

Will this be the catalyst for WCarr development that the Euro and GFS keep developing?

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

So falling apart in the Caribbean wouldn't necessarily be the end of it?

[aspen]

Will this be the catalyst for WCarr development that the Euro and GFS keep developing?

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

So falling apart in the Caribbean wouldn't necessarily be the end of it?

Perhaps similar to Harvey: forming as a small TS before the Lesser Antilles, getting ripped apart in the Caribbean, and regenerating later in the WCar/Gulf.

[AnnularCane]

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

So falling apart in the Caribbean wouldn't necessarily be the end of it?

Perhaps similar to Harvey: forming as a small TS before the Lesser Antilles, getting ripped apart in the Caribbean, and regenerating later in the WCar/Gulf.

Yeah, Harvey instantly came to mind.

[Category5Kaiju]

Ah yes Harvey, the ultimate Atlantic zombie.

[cycloneye]

No, is not an eye.

[Stormybajan]

Yes, But it may spin up before the islands. If it does then it may stay a weak TD and pulse convection... or open back to a wave until the western carrib.

So falling apart in the Caribbean wouldn't necessarily be the end of it?

Perhaps similar to Harvey: forming as a small TS before the Lesser Antilles, getting ripped apart in the Caribbean, and regenerating later in the WCar/Gulf.

Harvey is definitely the model this wave is trying to take, but lets hope this mirrors more a TS Bret and TS Don in 2017. Also seems to be a bit of dry air affecting the wave right now if im seeing correctly?

[Aric Dunn]

So falling apart in the Caribbean wouldn't necessarily be the end of it?

Perhaps similar to Harvey: forming as a small TS before the Lesser Antilles, getting ripped apart in the Caribbean, and regenerating later in the WCar/Gulf.

Harvey is definitely the model this wave is trying to take, but lets hope this mirrors more a TS Bret and TS Don in 2017. Also seems to be a bit of dry air affecting the wave right now if im seeing correctly?

At the moment it just looks like your normal daily pulse down phase. Dry air is still well north.. currently has a good moisture stream.

[Shell Mound]

Perhaps similar to Harvey: forming as a small TS before the Lesser Antilles, getting ripped apart in the Caribbean, and regenerating later in the WCar/Gulf.

Harvey is definitely the model this wave is trying to take, but lets hope this mirrors more a TS Bret and TS Don in 2017. Also seems to be a bit of dry air affecting the wave right now if im seeing correctly?

At the moment it just looks like your normal daily pulse down phase. Dry air is still well north.. currently has a good moisture stream.

The 00Z ECMWF suggests further deepening/organisation through day three, whereupon the system encounters LL convergence (trade surge) near the Windwards. If the system manages to develop a closed low-level circulation overnight, then perhaps it could briefly attempt to attain low-end TS status, given its compact size and the relatively strong pressure gradient, that is, high ambient MSLP. Tropical Storm Don (2017) might be a decent analog.

[mcallum177]

Is this wave the one currently predicted on the 06z GFS run to impact texas near hour 264? I tried to track the 850 vorticity but lose it south of Jamaica on the GFS.

[Shell Mound]

Is this wave the one currently predicted on the 06z GFS run to impact texas near hour 264? I tried to track the 850 vorticity but lose it south of Jamaica on the GFS.

I believe so. Comparison with the 00Z ECMWF shows that the timing and placement match. Both models show the vorticity near Jamaica in a week.