ATL: ISAIAS - Post-Tropical - Discussion

[ColdMiser123]

68 KT FL wind in the eastern semicircle.

[northjaxpro]

A good deal of popups in that dry air.
Won't be dry that much longer.

https://i.imgur.com/lLDqVsn.png

Yes up in Georgia, so GCANE I am wondering a bit if it is beginning to moisten up a bi, at least mid levels, more over me here and. and across Eastern Georgia.

[drewschmaltz]

I think it could get interesting Palm Bay north to Titusville between 7pm and midnight. I wouldn't be surprised if some areas experienced cat 1 conditions and we get an upgrade back to hurricane this evening in that time period.

[Steve]

Inbound/backflow banding is picking up (though still light) per Miami radar.
https://radar.weather.gov/ridge/radar.p ... x&loop=yes

[tropicwatch]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 2nd day of the month at 17:16Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF96-5300
Storm Number & Year: 09 in 2020
Storm Name: Isaias (flight in the North Atlantic basin)
Mission Number: 19
Observation Number: 05

A. Time of Center Fix: 2nd day of the month at 16:39:40Z
B. Center Fix Coordinates: 27.33N 79.62W
B. Center Fix Location: 51 statute miles (82 km) to the NNE (33°) from West Palm Beach, FL, USA.
C. Minimum Height at Standard Level: 1,395m (4,577ft) at 850mb
D. Minimum Sea Level Pressure: 996mb (29.42 inHg) - Extrapolated
E. Dropsonde Surface Wind at Center (Undecoded): NA
F. Eye Character: Not Available
G. Eye Shape: Not Available
H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 63kts (72.5mph)
I. Location & Time of the Estimated Maximum Surface Wind Inbound: 10 nautical miles (12 statute miles) to the NNW (328°) of center fix at 16:36:00Z
J. Maximum Flight Level Wind Inbound: From 78° at 60kts (From the ENE at 69.0mph)
K. Location & Time of the Maximum Flight Level Wind Inbound: 29 nautical miles (33 statute miles) to the NW (324°) of center fix at 16:29:30Z
L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 55kts (63.3mph)
M. Location & Time of the Estimated Maximum Surface Wind Outbound: 88 nautical miles (101 statute miles) to the E (91°) of center fix at 17:08:00Z
N. Maximum Flight Level Wind Outbound: From 170° at 68kts (From the S at 78.3mph)
O. Location & Time of the Maximum Flight Level Wind Outbound: 62 nautical miles (71 statute miles) to the E (91°) of center fix at 16:59:00Z
P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 19°C (66°F) at a pressure alt. of 1,529m (5,016ft)
Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 26°C (79°F) at a pressure alt. of 1,544m (5,066ft)
R. Dewpoint Temp (collected at same location as temp inside eye): 6°C (43°F)
R. Sea Surface Temp (collected at same location as temp inside eye): Not Available
S. Fix Determined By: Penetration, Wind, Pressure and Temperature
S. Fix Level: 850mb
T. Navigational Fix Accuracy: 0.02 nautical miles
T. Meteorological Accuracy: 1.75 nautical miles

Remarks Section:

Maximum Flight Level Wind: 68kts (~ 78.3mph) which was observed 62 nautical miles (71 statute miles) to the E (91°) from the flight level center at 16:59:00Z
Sea Level Pressure Extrapolation From: 850mb
General Note About Vortex Messages:
- Reported winds are usually averaged over a 10 second period. (The National Hurricane Center's advisory wind speeds are the highest expected winds averaged over a 1 minute period.)

[alan1961]

The ISS view of Tropical Storm Isaias

[GCANE]

A good deal of popups in that dry air.
Won't be dry that much longer.

https://i.imgur.com/lLDqVsn.png

Yes up in Georgia, so GCANE I am wondering a bit if it is beginning to moisten up a bi, at least mid levels, more over me here and. and across Eastern Georgia.

It looks that way.

Big pool of 4500 CAPE air for the convection to work with right off the coast.

And TCs usually ramp up quickly when they track into such highly unstable air.

[StormingB81]

I hope they didn’t drop the Hurricane warnings to quick for the East coast of Florida here

[CronkPSU]

would they round up and bring it back to a hurricane for the 2PM update advisory?

[northjaxpro]

Well, the first significant spiral band from the outer periphery of Isaias is rotating in toward the Northeast Florida and is approaching Saint Augustine and will get into Southern Duval County and pivot inland.

So it begins here across the Northeast Florida area..

[psyclone]

Hopefully they take advantage of the 2pm advisory to hoist some hurricane watches up north. Looks warranted

[ScottNAtlanta]

Product: Air Force Vortex Message (URNT12 KNHC)

P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 19°C (66°F) at a pressure alt. of 1,529m (5,016ft)
Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 26°C (79°F) at a pressure alt. of 1,544m (5,066ft)
R. Dewpoint Temp (collected at same location as temp inside eye): 6°C (43°F)

That's an awfully dry dewpoint in the eye, but the temperature differential is much better than it has been

[aspen]

So Isaias has 30-36 more hours over water until landfall in NC/SC, and as it gets closer it’ll apparently be moving into a more favorable UL environment from what has been posted here...I’m still a bit skeptical that it will exceed 65 kt again because the core is in pretty lackluster shape and it could make landfall on the Florida coast today. Seems like it’ll probably stay around 60-65 kt before landfall, but that’s just my take and I’m not a pro met.

[tropicwatch]

Thinking the NHC might wait until the HH finishes it NE to SW pass before pulling the trigger on the next update.

[emeraldislenc]

What are the chances it will be a hurricane when it hits NC?

[EquusStorm]

I worry that with the main focus on Florida, the Carolinas will let down their guard and get a far nastier hit than expected; with the structural improvement might have some real surge and power outage issues

[NDG]

For the NHC to upgrade it to Hurricane recon will have to find flight level winds higher than 75 knots and SFMR higher than 65 knots and convection will have to persistent because if they collapse again so will the winds.

[tropicwatch]

Interesting no upgrade on winds and no new watches/warnings.

[southportwxfan]

So, If I'm reading all this correctly Recon has found almost hurricane force winds again (72mph). This storm is expected to come into more favorable conditions as it moves away from Florida and towards the Carolinas. It will be tracking over very warm waters without the shear which has kept it in check and the air mass is unstable. All things which could ramp it up. But it will be moving quickly and as of right now the central "eye wall" lacks decent structure. So, is this a toss up as to whether it becomes a hurricane again? Or are the odds moving towards it becoming a hurricane again, and even a very strong Cat 1? Since I am in the bullseye of this storm, I am starting to get concerned again!!

[toad strangler]

Some nice gusts in Saint Lucie West up in the 40’s but very dry as you all can see on radar. Occasional light sprinkle. My dogs love the gusts and stand towards them with noses pointed up.