ATL: LAURA - Post-Tropical - Discussion

[aspen]

I wonder if their first track for TD13/future Laura will be through the Greater Antilles like the GFS, significantly north of the islands like the HWRF/HMON, or something in the middle.

[galaxy401]

I wonder how many times have we seen posts in which they don't expect an upgrade at all only for the upgrade to be made not even 5 minutes later. Not just future Laura, but other storms too (including Isaias). It's a Storm2k tradition.

I'm not targeting specific posters I've seen that a lot by a lot of people including myself.

[Kazmit]

Classic... people finally starting to side with the GFS/Euro, and then the NHC upgrades it to a TD mere minutes later.

[toad strangler]

 http://twitter.com/TropicalTidbits/status/1296273429876879361

[AxaltaRacing24]

I wonder if their first track for TD13/future Laura will be through the Greater Antilles like the GFS, significantly north of the islands like the HWRF/HMON, or something in the middle.

they're likely gonna pull a dorian and forecast a strong ts at first. when the 2 options are cat 2/3 or death, you kinda have to split the middle initially.

[MarioProtVI]

 https://twitter.com/AndyHazelton/status/1296274541048729600

[eastcoastFL]

A bit surprised NHC classified this already when the recent ASCAT pass did not show any northerly winds west of the center. Going to be interesting to read the discussion and intensity forecast.

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

[Evil Jeremy]

Levi Cowan had to back paddle.

Clearly the bypassing of PTC caught a lot of people in the tropical weather community off guard. Again, it's not a huge deal, it's almost technical semantics, but it's still interesting how surprising the move is

[DestinHurricane]

A bit surprised NHC classified this already when the recent ASCAT pass did not show any northerly winds west of the center. Going to be interesting to read the discussion and intensity forecast.

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

TVCN is north of islands so I would guess they go with that.

[caneseddy]

A bit surprised NHC classified this already when the recent ASCAT pass did not show any northerly winds west of the center. Going to be interesting to read the discussion and intensity forecast.

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

I think the would do a skirt of the northern islands as TVCN showed north of islands track

Intensity agree on a strong TS. Too soon to put the H on the cone

[DestinHurricane]

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

I think the would do a skirt of the northern islands as TVCN showed north of islands track

Intensity agree on a strong TS. Too soon to put the H on the cone

I would say there's a chance they put the H on the cone. They have been bullish all along and have other tools that aren't available to the public. Plus they usually follow that IVCN.

[eastcoastFL]

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

I think the would do a skirt of the northern islands as TVCN showed north of islands track

Intensity agree on a strong TS. Too soon to put the H on the cone

They have plenty of time to bump up intensity so that seems like the best bet and a mention of the “low confidence” in guidance at this time.

[SFLcane]

All I gotta say tonight is if TD 13 gets north of the islands intact look out.

[gfsperpendicular]

https://twitter.com/derekortt/status/1296273966991114240?s=21

epic fail by the GFS and ECMWF again this year. Never thought the models to look at would be the Canadian and ICON

King Euro is dead.

All hail King CMC. Long live the king.

On topic, I'm excited to see the initial discussion and intensity forecast. Will they choose the Euro/GFS coalition or the "everyone else" alliance?

[sma10]

Yes looking forward to this discussion. Obviously, they will mention the great disparity between the GFS/EURO (dissipation) and the hurricane models (major hurricane), but am most interested in how they sort out their specific 120 hr forecast. Certainly they cannot mirror the HWRF solution of a 130kt hurricane over Dade County; yet they are also not going to forecast a dissipated remnant low. My guess -- they will split the difference and put it around Andros Island at 55-65 knots

They’ll probably start with moderate progression maxing out with a strong TS at 120hrs. I wonder if they go north of the islands or over them

TVCN is north of islands so I would guess they go with that.

Yeah, not surprised that TVCN is north of islands. Even EURO is north of islands, just doesn't do anything with it

[toad strangler]

All I gotta say tonight is if TD 13 gets north of the islands intact look out.

... per Levi Cowan

[GeneratorPower]

Important note: the NHC didn't spontaneously decide to generate TD13. The storm itself triggered the designation.

[eastcoastFL]

Anyone else refreshing the nhc site like a madman?

[caneseddy]

ZCZC MIATCMAT3 ALL
TTAA00 KNHC DDHHMM

TROPICAL DEPRESSION THIRTEEN FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL132020
0300 UTC THU AUG 20 2020

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE GOVERNMENT OF THE NETHERLANDS HAS ISSUED A TROPICAL STORM
WATCH FOR SABA AND ST. EUSTATIUS.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* SABA AND ST. EUSTATIUS

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

INTERESTS ELSEWHERE IN THE NORTHERN LEEWARD ISLANDS...THE VIRGIN
ISLANDS...AND PUERTO RICO SHOULD MONITOR THE PROGRESS OF THIS
SYSTEM...AS TROPICAL STORM WATCHES COULD BE REQUIRED FOR THOSE
AREAS ON THURSDAY.

TROPICAL DEPRESSION CENTER LOCATED NEAR 14.6N 47.9W AT 20/0300Z
POSITION ACCURATE WITHIN 45 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 295 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 14.6N 47.9W AT 20/0300Z
AT 20/0000Z CENTER WAS LOCATED NEAR 14.4N 47.3W

FORECAST VALID 20/1200Z 16.1N 50.8W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 21/0000Z 17.4N 54.6W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 40NE 40SE 0SW 30NW.

FORECAST VALID 21/1200Z 18.4N 58.4W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 70NE 60SE 0SW 50NW.

FORECAST VALID 22/0000Z 19.1N 62.1W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 90NE 80SE 0SW 70NW.

FORECAST VALID 22/1200Z 19.9N 65.9W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 40NE 0SE 0SW 40NW.
34 KT...110NE 90SE 30SW 90NW.

FORECAST VALID 23/0000Z 20.8N 69.7W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 40NE 0SE 0SW 40NW.
34 KT...110NE 90SE 30SW 90NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 24/0000Z 22.9N 76.7W
MAX WIND 60 KT...GUSTS 75 KT.

OUTLOOK VALID 25/0000Z 26.2N 82.2W
MAX WIND 60 KT...GUSTS 75 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 14.6N 47.9W

INTERMEDIATE PUBLIC ADVISORY...WTNT33 KNHC/MIATCPAT3...AT 20/0600Z

NEXT ADVISORY AT 20/0900Z

$$
FORECASTER CANGIALOSI


NNNN

[Evil Jeremy]

70mph, just off the coast of Naples in 5 days per NHC forecast.