ATL: HERMINE - Post-Tropical - Discussion

[StormHunter72]

Still very serious in the bay area especially pasco

[Happy Pelican]

Tourists are packing the NJ barriers and still not a peep from the Gov.

[seahawkjd]

Here's the newest short term forecast out of Morehead City, NC

.NEAR TERM /THROUGH TONIGHT/...
As of 320 PM Thu...TS Hermine now entering srn SC and moving
quickly northeastward. Biggest threat through tonight continues to
be heavy rain potential and flash flooding. SPC meso analysis
indicates large 850 MB moisture transport vectors from the SSW.
Convective tropical rain bands with 3+ inch/hr rain rates setting
up across the SC and NC waters south of the Crystal Coast. Will
continue to monitor these bands should they move onshore later
this afternoon into the evening for potential flash flood
warnings. Other threat will be tornado potential. NSSL WRF/HRRR
indicate axis of high cape and SRH this evening superimposed just
east and south of the northeastward moving cyclone. Area from
Jacksonville to the Outer Banks will be monitored for tornado
threat this evening.

[StormHunter72]

stay safe

[Laser30033003]

there is still a lot of junk left in the Gulf......

[OuterBanker]

Interestin note. Rather drastic change from NWS on locals forcast. This am they has possible tropical storm conditions today tonight and tomorrow. Clearing Sunday and Monday. It now includes Sunday, Sunday night and Monday.

[StormHunter72]

there is still a lot of junk left in the Gulf......

Yep. Kind of curious if a new low may be forming....

[johngaltfla]

The 1700 ET update is going to be INTERESTING after looking at the Euro. Not going to be a good outcome for those not paying attention if it confirms.

[psyclone]

the gauge at the tarpon outfall canal reported 22.36". this is literally less than a mile from me. I only observed about 14.5" but there's no doubt that's an underestimate because my gauge overflowed. anyway you slice it that's a boatload of water. And I have a roof leak. I am over tropical weather. I really hope the rest of the season gives us a break. Give me sun...please.

[cycloneye]

BULLETIN
TROPICAL STORM HERMINE ADVISORY NUMBER 22
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
500 PM EDT FRI SEP 02 2016

...CENTER OF HERMINE PASSING NEAR CHARLESTON WITH STRONG WINDS
AND HEAVY RAIN...
...DANGEROUS STORM SURGE EXPECTED IN THE HAMPTON ROADS AREA...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...33.0N 80.5W
ABOUT 30 MI...50 KM WNW OF CHARLESTON SOUTH CAROLINA
ABOUT 55 MI...90 KM NNE OF HILTON HEAD ISLAND SOUTH CAROLINA
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...NE OR 55 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...993 MB...29.33 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been extended northward from Fenwick
Island, Delaware, to Sandy Hook, New Jersey, including Delaware Bay.

The Tropical Storm Warning has been discontinued south of Altamaha
Sound, Georgia.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Altamaha Sound to Sandy Hook
* Pamlico and Albemarle Sounds
* Chesapeake Bay from Drum Point southward
* Tidal Potomac from Cobb Island eastward
* Delaware Bay

A Tropical Storm Watch is in effect for...
* North of Sandy Hook to west of Watch Hill

Interests elsewhere along the United States northeast coast should
monitor the progress of this system.



TROPICAL STORM HERMINE DISCUSSION NUMBER 22
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
500 PM EDT FRI SEP 02 2016

While the cloud pattern of Hermine has become elongated north and
east of the center, and the central convective tops have warmed,
numerous surface observations of 40-kt winds along the South
Carolina coast support maintaining an initial intensity of 45 kt for
this advisory. While the center of Hermine remains over land for
the next 12 to 18 hours, little change in intensity is expected,
as the strongest winds should remain over the coastal waters of the
Carolinas. After the center moves offshore, intensification is
expected through a combination of diabatic and baroclinic processes.
The global models continue to show Hermine interacting with a potent
upper-level shortwave trough in 2-3 days, and the system is expected
to restrengthen to near hurricane force in 48 to 72 hours. As the
upper-level forcing moves away, slow weakening is expected later in
the period. The NHC intensity forecast is above the tropical
cyclone guidance suite and is based largely on global models.

The initial motion estimate is 055/17, as Hermine is currently
embedded in deep-layer southwesterly flow ahead of a positively-
tilted mid-latitude trough. During the next 36 to 48 hours the
cyclone should gradually slow down and then turn more poleward as
the shortwave trough amplifies over the central Appalachians and
mid-Atlantic states. This trough interacts with and superimposes
itself on top of Hermine between 48 and 72 hours. Not surprisingly,
there are differences in the details of how the model guidance
handles the motion of Hermine during this time, with the ECMWF and
ECMWF ensemble mean along the western side of the guidance by 72
hours, and the GFS, HWRF, and UKMET farther to the east. Note that
the interaction between Hermine and the upper trough could result in
some looping motions that are not captured by the 12 and 24 hour
spacing of the official NHC forecast points. Late in the forecast
period, a northeastward motion is expected as the upper trough
slides eastward. Spread continues in the guidance at those times
as well, with the HWRF joining the ECMWF on the left side of the
guidance envelope at those times. Overall, the new NHC forecast has
been adjusted a bit to the left and is close to the middle of the
guidance envelope. This track is near the GEFS ensemble mean and a
blend of the GFS and ECMWF. Needless to say, small changes in the
eventual track of Hermine could result in large changes in impacts
along the mid-Atlantic coast.

The NHC forecast shows Hermine as a post-tropical cyclone in 36
hours, but model fields do not show it undergoing a full
extratropical transition, as it instead appears to acquire a warm
seclusion structure with a strong low-level vortex underneath an
upper-level low. There is a possibility that the system could
regain some tropical characteristics in 3-5 days, but this remains
uncertain. It is important to remind users that Hermine is expected
to remain a dangerous cyclone through the forecast period regardless
of the details of its structure.

Based on the latest forecast, tropical storm warnings have been
expanded northward along the U.S. mid-Atlantic coast to Sandy Hook,
New Jersey.

KEY MESSAGE:

1. Hermine is expected to become a post-tropical cyclone while still
producing hazardous winds and storm surge over land. NWS policy
allows NHC to write advisories on and issue tropical storm watches
and warnings for post-tropical cyclones, when the system continues
to pose a significant threat to life and property. NHC and the NWS
Eastern Region have decided that this option will be invoked for
Hermine. After Hermine becomes a post-tropical cyclone, NHC will
continue to issue its full suite of advisory and warning products
for as long as the system remains a significant threat to land.

FORECAST POSITIONS AND MAX WINDS

INIT 02/2100Z 33.0N 80.5W 45 KT 50 MPH...INLAND
12H 03/0600Z 34.5N 77.9W 45 KT 50 MPH...INLAND
24H 03/1800Z 36.1N 75.0W 50 KT 60 MPH...OVER WATER
36H 04/0600Z 37.1N 73.1W 55 KT 65 MPH...POST-TROPICAL
48H 04/1800Z 37.8N 72.5W 60 KT 70 MPH...POST-TROPICAL
72H 05/1800Z 38.4N 72.8W 65 KT 75 MPH...POST-TROPICAL
96H 06/1800Z 39.7N 71.0W 60 KT 70 MPH...POST-TROPICAL
120H 07/1800Z 40.5N 69.5W 50 KT 60 MPH...POST-TROPICAL

$$
Forecaster Brennan

[StormHunter72]

the gauge at the tarpon outfall canal reported 22.36". this is literally less than a mile from me. I only observed about 14.5" but there's no doubt that's an underestimate because my gauge overflowed. anyway you slice it that's a boatload of water. And I have a roof leak. I am over tropical weather. I really hope the rest of the season gives us a break. Give me sun...please.

1000% agreed

[StormHunter72]

Pasco Has a TARGET or Bullseye on it. Let it STOP!!!!!

[NJWxHurricane]

Warnings up.

[WilmingtonSandbar]

Tourists are packing the NJ barriers and still not a peep from the Gov.

I'm wondering if it might be because storm effects won't be felt for at least 48 hours?

[StormHunter72]

The 1700 ET update is going to be INTERESTING after looking at the Euro. Not going to be a good outcome for those not paying attention if it confirms.

where?

[johngaltfla]

Warnings up.

Yup. I hope NJ takes this seriously. It won't take much of a deviation of this storm once it becomes a hurricane to repeat Sandy or sad to say worse. I know it is a holiday weekend thus why I would like to think the government would get the warnings out faster and start clearing the beaches NOW.

[johngaltfla]

The 1700 ET update is going to be INTERESTING after looking at the Euro. Not going to be a good outcome for those not paying attention if it confirms.

where?

NJ/NYC. The Tropical Storm warnings were extended to Sandy Hook, NJ by the NHC with the 1700 update. NYC is still under a watch but it won't take much of a jog to the west to create massive stupidity as everyone appears focused on the holiday weekend and not prepping for the storm up there.

[Fishing]

What is her movement right now? Sure seems like she's been West of us (Charleston) for a long time. We have had some trees down and rather gusty winds and really not a ton of rain. This has been the most fun I've had tracking in over a decade I think . Prayers to those that suffered damage!!
Fishing

[johngaltfla]

What is her movement right now? Sure seems like she's been West of us (Charleston) for a long time. We have had some trees down and rather gusty winds and really not a ton of rain. This has been the most fun I've had tracking in over a decade I think . Prayers to those that suffered damage!!
Fishing

NE at 20. Should be offshore tomorrow again and strengthen back into a hurricane.

[gatorcane]

So nobody is taking this seriously in New Jersey and New York?

Just read the 5pm NHC discussion and if I lived there, I would!