ATL: INVEST 97L - Discussion

[Subtrop]

AL, 97, 2023073012, , BEST, 0, 328N, 773W, 25, 1012, DB, 34, NEQ, 0, 0, 0, 0, 1014, 130, 60, 0, 0, L, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 016, SPAWNINVEST, al772023 to al972023,

https://ftp.nhc.noaa.gov/atcf/btk/bal972023.dat

[cycloneye]

Off the Carolina Coast:
Shower and thunderstorm activity has increased in association with a
trough of low pressure that recently emerged off the Carolina
coastline, and is currently located about 100 miles south of
Wilmington, North Carolina. Environmental conditions appear
generally favorable for some additional development over the next
day or two as the system gradually accelerates east-northeastward
into the northwestern Atlantic ocean. Afterwards, this system is
likely to merge with a frontal boundary.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.

[MGC]

Looks like a low is trying to close off. Lots of convection. Development odds should increase today. No threat to land......MGC

[wxman57]

Looks like a frontal low. Has no future.

[Sciencerocks]

[LarryWx]

GFS, Euro, and CMC all try to spin this up, although it's probably not going to be able to detach from the front. I think 20% chance of development is about right.

But this isn't currently attached to a front. The very weak surface low is currently centered over the open ocean ~75 miles east of Cape Fear. Dewpoints are in the mid to upper 70s throughout SE NC all the way back to Lumberton including 78 at Wilmington and up to Cape Hatteras's 75. The cold front is depicted on surface maps to be ~175-200 miles N of the low center.

[ElectricStorm]

GFS, Euro, and CMC all try to spin this up, although it's probably not going to be able to detach from the front. I think 20% chance of development is about right.

But this isn't currently attached to a front. The very weak surface low is currently centered over the open ocean ~75 miles east of Cape Fear. Dewpoints are in the mid to upper 70s throughout SE NC all the way back to Lumberton including 78 at Wilmington and up to Cape Hatteras's 75. The cold front is depicted on surface maps to be ~175-200 miles N of the low center.

Well in that case it might have a higher chance then

[cycloneye]

Off the North Carolina Coast (AL97):
Shower and thunderstorm activity is showing some signs of
organization in association with a trough of low pressure located
about 100 miles southeast of Morehead City, North Carolina.
Environmental conditions appear generally favorable for some
additional development over the next day or so as the system
gradually accelerates east-northeastward into the northwestern
Atlantic Ocean. Afterwards, this system is likely to merge with a
frontal boundary.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

[ScottNAtlanta]

You can definitely see a LLC spinning under the clouds. Looks to be a fish spinner if anything

[LarryWx]

This buoy 150 NM E of Hatteras will be interesting to follow during the next few hours. The recent wind gusts have been well into the 20s of knots, but that's pretty normal for out there. Also, the direction has been SSW as opposed to, say, a direction like SE that would make me think a surface low is developing. SLPs have fallen modestly but are still up at 1011.5 mb. That modest drop may be more related to diurnal forces as well as that aforementioned approaching cold front to the NW:

https://www.ndbc.noaa.gov/station_page. ... tion=41001

[Sciencerocks]

Looks to have a LLC. I wouldn't be shocked to see this named in the next 24-36 hours.

[Sciencerocks]

[cycloneye]

A. TROPICAL DISTURBANCE (97L)

B. 31/0000Z

C. 34.8N

D. 72.5W

E. FIVE/GOES-E

F. T1.0/1.0

G. IR/EIR/SWIR/VIS

H. REMARKS...GREATER THAN 2/10 BANDING RESULTS IN A DT OF 1.0. MET AND
PT ARE ALSO 1.0. THE FT IS BASED ON THE DT.

I. ADDL POSITIONS

NIL


...TURK

[LarryWx]

A. TROPICAL DISTURBANCE (97L)

B. 31/0000Z

C. 34.8N

D. 72.5W

E. FIVE/GOES-E

F. T1.0/1.0

G. IR/EIR/SWIR/VIS

H. REMARKS...GREATER THAN 2/10 BANDING RESULTS IN A DT OF 1.0. MET AND
PT ARE ALSO 1.0. THE FT IS BASED ON THE DT.

I. ADDL POSITIONS

NIL


...TURK

So, with Dvorak at 1.0, this isn't yet a TD. This is just east of that buoy that is 150 nm E of Hatteras. That buoy had a wind shift to the NE 4 hours ago.

[Hammy]

Good chance this missed it's (brief) opportunity to organize further, it's looking worse than it did this afternoon

[LarryWx]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Mon Jul 31 2023

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

2. Off the U.S. Mid-Atlantic Coast (AL97):
Shower and thunderstorm activity has recently shown little change
in organization in association with an area of low pressure located
offshore of the U.S. Mid-Atlantic coast. Environmental conditions
appear generally favorable for some development, and a short-lived
tropical cyclone could develop before the system merges with a
frontal boundary within the next day or so. Regardless of whether
the system becomes tropical or not, gale-force winds are
expected starting later today, and additional information on this
system can be found in High Seas Forecasts issued by the National
Weather Service.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

[Teban54]

Down to 20/20

2. Off the U.S. Mid-Atlantic Coast (AL97):
Shower and thunderstorm activity has changed little in association
with an area of low pressure located offshore of the
U.S. Mid-Atlantic coast. The system appears to be acquiring
non-tropical characteristics as it begins to merge with a frontal
boundary, and its chances of becoming a tropical cyclone appear to
be decreasing. Regardless, the low is expected to begin producing
gale-force winds today while it moves quickly toward the
east-northeast at about 30 mph, and additional information on this
system can be found in High Seas Forecasts issued by the National
Weather Service.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent.

[cycloneye]

Is now Extratropical.

AL, 97, 2023073112, , BEST, 0, 359N, 676W, 30, 1006, EX

[Sciencerocks]

[tolakram]

Ah well, I enjoy watching these odd little systems.