ATL: INVEST 92L - Discussion

[kevin]

Another 33 kt SFMR. Note that they haven't sampled the southern section with the majority of the convection yet.

[kevin]

Recon found a center region with only 10 kt FL winds as well as 38 kt SFMR and 35 kt Est. Sfc. Wind. If NHC deems that the structure is sufficient for a TC, the wind measurements support TS strength. I at least expect them to go with a TD.

[kevin]

[NDG]

I would had thought that there would had been an upgrade by now, how much more evidence do they need that it has well defined LLC and plenty strong flight level and surface winds.

BTW, NW winds here in the Orlando area, fairly large circulation for its size.

[MarioProtVI]

https://i.imgur.com/xiJwMts.jpeg

Looks like a TD but I feel they may hold back bc of the anemic convection looks.

[GCANE]

CAPE has been increasing all morning. Now at 3500.
Surface winds likely sufficient enough for heat to be pulled out of the Gulf Stream.

[LarryWx]

The closest offshore buoy to 92L is 41010 (near 28.9N, 78.5W) vs 92L being roughly 30N, 79.5W, meaning the buoy is ~100 miles SE of 92L. That may be too far away to be of value due to the tiny size of 92L. Fwiw, it has 10 knot S winds, SLP of 1019 mb, dewpoint of 76F, and RH of 89%:

Station 41010
NDBC
Location: 28.878N 78.467W
Date: Fri, 21 Jun 2024 13:10:00 UTC
Winds: S (180°) at 9.7 kt gusting to 13.6 kt
Atmospheric Pressure: 30.08 in
Air Temperature: 79.9 F
Dew Point: 76.3 F
Water Temperature: 80.6 F

[LarryWx]

92L is now roughly centered over the Gulf Stream. So, SSTs have risen from yesterday’s ~81F to about the warmest to be crossed or in the 83-84F range. These warmest waters extend W to ~80 west long. Then they cool back to 81-2F to the coast.

[GCANE]

Seeing a slight increase in helicity along the dryline.
Could get a couple tornadoes out of this along the coast, especially around sunset.

[MGC]

I think it would be prudent for the NHC to issue PTC advisories at this point. Clearly a circulation and 92L is approaching Gulf Stream. At most this will be a TD or minimal TS at landfall......MGC

[ricka47]

Seeing a slight increase in helicity along the dryline.
Could get a couple tornadoes out of this along the coast, especially around sunset.

Nice and sunny here on Amelia Island now. Has been windy for a few days. I hope we won't see tornadoes!

[cycloneye]

 https://x.com/NHC_TAFB/status/1804153182999961608

[GCANE]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 21st day of the month at 14:02Z

Minimum Sea Level Pressure: 1014mb (29.95 inHg) - Extrapolated

Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 37kts (42.6mph)
Location & Time of the Estimated Maximum Surface Wind Outbound: 5 nautical miles to the E (95°) of center fix at 13:40:30Z

[LarryWx]

 https://x.com/NHC_TAFB/status/1804153182999961608

So, center is on the far N edge of the main convection. Is this organized enough to warrant TD status? Opinions?

[chaser1]

Must be lacking a west wind at the surface.

[GCANE]

4000 CAPE in the Bahamas. I wouldn't be surprised to see a slight feeder band develop before making landfall.

[BobHarlem]

There's a bit of a flare up of convection around the center in the last half hour or so.

[cycloneye]

STWO:

Southwestern Atlantic Ocean (AL92):
Updated: Recent data from an Air Force Reserve reconnaissance
aircraft and visible satellite imagery indicate that the area of
low pressure located about 120 miles east of Jacksonville, Florida,
has developed a well-defined center of circulation and is
producing winds to near 35 mph, but the associated showers and
thunderstorms are not quite organized enough for this system to be
considered a tropical cyclone. However, only a small increase in
the organization of the showers and thunderstorms could result in
the formation of a short-lived tropical depression before it
reaches the coast of northeastern Florida or Georgia tonight, and
interests there should monitor its progress. For more information,
refer to High Seas Forecasts issued by the National Weather Service,
as well as local forecasts issued by your local National Weather
Service Forecast Office.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...medium...60 percent.

[Nuno]

 https://x.com/NHC_TAFB/status/1804153182999961608

So, center is on the far N edge of the main convection. Is this organized enough to warrant TD status? Opinions?

It's clearly a TD. It's so strange how it isn't at least designated as a *Potential* TC.

[LarryWx]

 https://x.com/NHC_TAFB/status/1804153182999961608

So, center is on the far N edge of the main convection. Is this organized enough to warrant TD status? Opinions?

It's clearly a TD. It's so strange how it isn't at least designated as a *Potential* TC.

Convection isn’t quite organized enough to be designated a TD per NHC as of now.