ATL: HERMINE - Post-Tropical - Discussion

[Chris_in_Tampa]

Through 10:32pm EDT:

[HurricaneBelle]

I cannot really tell myself since Hermine is moving so slow and all the clouds are moving around, does it appear at all that Hermine has/or is starting to make a turn to the north/ northeast?

Still moving due east if you compare the 5PM/8PM advisory coordinates. But convection is starting to build north and northwest of the center.

[funster]

NHC shifts a little west. Notes that some models have a bigger western shift

The initial motion is a slow northward drift 010/03 kt. Water vapor
imagery indicates that an upper-level low has developed east of the
DelMarVa peninsula and is dropping to the south of Hermine's surface
center. The latest model guidance is forecasting the surface and
mid- to upper-level lows to rotate counterclockwise around each
other for the next 24-36 hours before becoming vertically stacked by
36-48 hours. This cyclonic interaction has resulted in a significant
westward shift in the global model tracks, especially by the UKMET
and ECMWF models. As a result, the official forecast has been
shifted a little to the west of the previous advisory track, but
lies along the extreme eastern side of the guidance envelope in the
event that the models shift back to the east since such complex
interactions are difficult to forecast from cycle to cycle.

http://www.nhc.noaa.gov/text/refresh/MI ... 0857.shtml

[cycloneye]

POST-TROPICAL CYCLONE HERMINE DISCUSSION NUMBER 32
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
500 AM AST MON SEP 05 2016

Hermine remains a post-tropical cyclone with a cloud pattern more
reminiscent of an extratropical low. However, moderate convection
has been developing just north of the surface center in the northern
semicircle during the past few hours within a region of increasing
upper-level diffluence. Data from an earlier reconnaissance mission
along with recent scatterometer data suggest that the intensity
remains unchanged at 60 kt.

The initial motion is a slow northward drift 010/03 kt. Water vapor
imagery indicates that an upper-level low has developed east of the
DelMarVa peninsula and is dropping to the south of Hermine's surface
center. The latest model guidance is forecasting the surface and
mid- to upper-level lows to rotate counterclockwise around each
other for the next 24-36 hours before becoming vertically stacked by
36-48 hours. This cyclonic interaction has resulted in a significant
westward shift in the global model tracks, especially by the UKMET
and ECMWF models. As a result, the official forecast has been
shifted a little to the west of the previous advisory track, but
lies along the extreme eastern side of the guidance envelope in the
event that the models shift back to the east since such complex
interactions are difficult to forecast from cycle to cycle.

The upper-level flow across Hermine is forecast by all of the global
models to continue to become more difluent during the next 24 hours,
which should aid in the development of deep convection near the
low-level center. By 36-48 hours, the deep-layer vertical is
expected to decrease from the current 45 kt to less than 10 kt, a
pattern that is usually conducive for intensification. However,
those favorable upper-level conditions will be negated by much
cooler sea-surface temperatures of 23-25 deg C when Hermine will be
north of the Gulf Stream at that time. The global models are in very
agreement on both Hermine weakening and the 34-kt wind field
steadily shrinking by 24 hours and beyond. Further weakening is
expected through day 4, and both the ECMWF and GFS show Hermine
dissipating by day 5 over the cold waters of the North Atlantic.

The initial 50-kt wind radii have been adjusted based on data from
the reconnaissance aircraft and an earlier ASCAT overpass.

FORECAST POSITIONS AND MAX WINDS

INIT 05/0900Z 37.7N 68.3W 60 KT 70 MPH...POST-TROPICAL
12H 05/1800Z 38.0N 69.1W 60 KT 70 MPH...POST-TROPICAL
24H 06/0600Z 38.6N 70.2W 55 KT 65 MPH...POST-TROPICAL
36H 06/1800Z 39.0N 70.4W 45 KT 50 MPH...POST-TROPICAL
48H 07/0600Z 39.7N 70.1W 40 KT 45 MPH...POST-TROPICAL
72H 08/0600Z 40.7N 67.7W 35 KT 40 MPH...POST-TROPICAL
96H 09/0600Z 43.0N 62.7W 30 KT 35 MPH...POST-TROPICAL
120H 10/0600Z...DISSIPATED

$$
Forecaster Stewart

[gatorcane]

What a nightmare of a storm to track when models are so inconsistent from cycle to cycle

[wxman57]

What a nightmare of a storm to track when models are so inconsistent from cycle to cycle

Steering currents are quite complex with the upper low in the area. Each model is handling the pattern a bit differently. Hermine may yet produce TS winds on Long Island and up to Cape Cod over the next day or two.

[Kazmit]

Hermine death/damage update:
4 have died.
At least $10 million damage (number should grow).

[abajan]

The advisories mention rip currents. But how many of us really know what they are? Only on reading this article did I realize that what I'd always assumed, was wrong. For some reason, I thought they ran almost parallel to the shore, not directly away from it! Very glad I read this.

[Happy Pelican]

Breathing a huge sigh of relief here on the NJ barriers!

Why, you guys got another 3 to 5 days of high surf and other problems.

Actually, compared to the forecast 2-3 days ago, yeah, we're all breathing a sigh of relief. Beside, school reopens tomorrow tomorrow so today is like the mom version of Christmas eve

[Extratropical94]

Mission #19 from today

[hipshot]

Breathing a huge sigh of relief here on the NJ barriers!

Why, you guys got another 3 to 5 days of high surf and other problems.

Actually, compared to the forecast 2-3 days ago, yeah, we're all breathing a sigh of relief. Beside, school reopens tomorrow tomorrow so today is like the mom version of Christmas eve

Well, I guess from all these posts , Hermine is a non-issue. I sure hope that is true because I have seen nothing that would demonstrate
that theres an "all's clear" been sounded by the NHC or anyone else as far as I can tell. Sure hope I'm wrong.!!

[NDG]

Wow, those coastal waters along the NE US are cooling off really quick, those anomalous warm waters were just at the immediate surface.

[Chris_in_Tampa]

Through 7:55pm EDT:

[bzukajo]

Winds picked up very significantly here in Douglas MA. We have a lot of trees coming down. The traffic on the online Scanner for south central MA is almost all about trees and power lines. http://www.websterpolice.com/live.shtml I heard more than a few limbs crack from the back property.

[Chris_in_Tampa]

Through 10:15pm EDT:

[Chris_in_Tampa]

Highest Flight Level Wind (30 sec. Avg.) since last vortex: 65 knots (~ 74.8 mph)
Highest Peak (10 sec. Avg.) Flight Level Wind since last vortex: 66 knots (~ 76.0 mph)
Highest SFMR Peak (10s Avg.) Sfc. Wind since last vortex: 49 knots (~ 56.4 mph)

Through 10:25pm EDT:

[Steve]

Wow, those coastal waters along the NE US are cooling off really quick, those anomalous warm waters were just at the immediate surface.

It's a massive system. It's not piling up ACE, but it should be doing a number on the SSTA's. It will certainly be interesting to see how much more the tropical Atlantic has up that way for this season

[Chris_in_Tampa]

Through 11:55pm EDT:

[Chris_in_Tampa]

Through 12:05am EDT:

[Chris_in_Tampa]

Through 12:55am EDT: