ATL: COLIN - Post-Tropical - Discussion

[zzh]

AL, 96, 2022070118, , BEST, 0, 318N, 804W, 30, 1016, LO, 34, NEQ, 0, 0, 0, 0, 1018, 120, 50, 0, 0, L, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 012, SPAWNINVEST, al732022 to al962022,

Thread at Talking Tropics forum that was the topic for this area.
https://www.storm2k.org/phpbb2/viewtopi ... 3#p2973803




https://www.fnmoc.navy.mil/tcweb/cgi-bin/tc_home.cgi

[kevin]

Another one! I didn't even notice that there was a system with potential off the SE coast until I saw NXStumpy's post an hour ago. And now it's already an invest. Would be interesting if this one manages to develop even though we've spent all this time last week looking at 95L and the wave behind 'Bonnie AKA PTC2 Methuselah' (and Bonnie itself of course).

[kevin]

One of the reasons that this might be activating now is that deep-layer shear has decreased considerably over the last 12 hours. At the current location of 96L shear was 40 knots 12 hours ago. Now it's roughly 25 knots. That's still a lot but the area of low shear has been moving closer to 96L with every 3 hour updated map.

[ChrisH-UK]

Here's the latest HRRR run, the global models show a brief patch in the area. I think the system is too small for the global models to see.

[tolakram]

eye-like feature

 https://twitter.com/UWCIMSS/status/1542922991545327616

[ScottNAtlanta]

One of the reasons that this might be activating now is that deep-layer shear has decreased considerably over the last 12 hours. At the current location of 96L shear was 40 knots 12 hours ago. Now it's roughly 25 knots. That's still a lot but the area of low shear has been moving closer to 96L with every 3 hour updated map.

It still looks pretty badly sheared on satellite

[LarryWx]

This system has given me 4" of rainfall today (most rain in one day here since 9/20/21). About 3.5" of that fell midnight-3 AM producing lots of street flooding.

[ChrisH-UK]

96L looks interesting on radar, a very tight rotation just off the coast.

[emeraldislenc]

Where r u Larry?

[Nimbus]

Circulation is just moving off the South Carolina coast, might pick up some energy from the gulf stream.

[ChrisH-UK]

96L is looking better on radar now however as you can see from the GOES-17 there is a lot of shear and the rotation only exist on the lower level.

[zhukm29]

Looks impressive for a 10/10 system.

[LarryWx]

Where r u Larry?

Savannah

[cycloneye]

1. Near the Southeastern US:
Satellite and radar images along with surface observations indicate
that a low pressure system is located along the coast of southern
South Carolina near Beaufort. Development, if any, of this system
should be slow to occur while it drifts northeastward along the
southeast U.S. coastline during the next couple of days. Regardless
of development, this system is expected to produce heavy rains,
which could cause flash flooding across portions of southeastern
Georgia and the Carolinas through tonight and into Saturday. See
products issued by the Weather Prediction Center and your local
National Weather Service forecast office for more details.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.

[Sciencerocks]

[Sciencerocks]

It is freaking amazing how well defined that LLC was and it is only the first of july. Not likely to develop but if it had formed further from land and with less shear maybe we'd be talking about another story.

[zhukm29]

Reports are coming in at Charleston with sustained winds of ~40 mph and gusts up to ~50+ mph. Certainly TS conditions could be at hand over the next few hours along the coast, even if the system has not been designated as a TC yet. Definitely one to watch, especially since it wasn't even on the map just 12 hours ago!

 https://twitter.com/webberweather/status/1543054700483817475




 https://twitter.com/WeatherFlowCHAS/status/1543040965115580418

[Europa non è lontana]

I am honestly surprised this hasn't been designated. To my unprofessional eye, it seems to meet the definition of a tropical cyclone. The only reason I could think of that the NHC is holding out would be the surface pressure or waiting to ensure the convection is sustained.

[zhukm29]

I am honestly surprised this hasn't been designated. To my unprofessional eye, it seems to meet the definition of a tropical cyclone. The only reason I could think of that the NHC is holding out would be the surface pressure or waiting to ensure the convection is sustained.

Yeah, I'm kind of surprised as well, since fast spin-ups like these have been designated in years prior. Maybe they are seeing something we aren't? That being said, I think Bertha jumped from 20 or 30% to a TC immediately, and it wasn't really that much different with what 96L has shown today. I guess it is a wait-and-see game at the moment, but I do think it'll be a good candidate for reanalysis if it isn't officially designated in real time.

[Nuno]

This is a clear and cut tropical cyclone.