ATL: ARTHUR - Post-Tropical - Discussion

[cycloneye]

Lowest pressure at pass 991.5 mbs.

[WxEnthus]

NHC still has it NOT becoming a hurricane until the 24 hr mark. Any chance if they upped that to 12 hr mark, or less, the OBX would be evacuating? At least the tourists?

NHC issues advisories at 11am, 2pm, 5pm, 8pm, 11pm, etc. They likely didn't change predictions at 2pm because they are awaiting hard data from recon planes. There are two flying into the storm atm and another sampling the atmosphere which will be fed into later model runs. They don't usually wildly alter things after every model run or based on satellite presentation alone. Will likely see updates to track and timing at the 5pm or they will issue a special advisory when conditions warrant.

[MaineWeatherNut]

200130 2944N 07902W 8426 01430 9922 +189 +159 192019 022 029 001 03

Pressure down to 992.2 mb with still a 22kt wind so they missed the Center...

[Aric Dunn]

Lowest pressure at pass 991.5 mbs.

damn 5 mb in a hour.. next pass or by the time the noaa plane gets there could be higher winds

also still due north..

if the nne motion does not start soon it will be left of the 11am forecat

[cycloneye]

There is the center.

[Aric Dunn]

next up the noaa plane its heading NW to SE now...

[SunnyThoughts]

Lowest pressure at pass 991.5 mbs.

damn 5 mb in a hour.. next pass or by the time the noaa plane gets there could be higher winds

also still due north..

if the nne motion does not start soon it will be left of the 11am forecat

yeah, looks to be following that 79 lon line straight northward right now. Hopefully starts turning soon.

[Hammy]

given the convection forming now on the NE side it'll be interesting to see what the winds are if they make another pass through in an hour or so.

[eastcoastFL]

Couldn't agree more. Looks better than some cat 1 canes. Especially this early in the year. Pretty amazing.

I can't remember a tropical storm having this clear of an eye. If it is not a hurricane now, it should be soon if trends continue:

[cycloneye]

AF vortex message.

URNT12 KNHC 022021
VORTEX DATA MESSAGE AL012014
A. 02/20:03:50Z
B. 29 deg 42 min N
079 deg 10 min W
C. 850 mb 1354 m
D. 67 kt
E. 070 deg 18 nm
F. 146 deg 71 kt
G. 068 deg 20 nm
H. 992 mb
I. 14 C / 1526 m
J. 20 C / 1525 m
K. 16 C / NA
L. Open NW
M. E30/34/25
N. 12345 / 08
O. 0.02 / 1.5 nm
P. AF301 0601A ARTHUR OB 10
MAX FL WIND 71 KT 068 / 20 NM 19:57:00Z
MAX FL TEMP 19 C 075 / 6 NM FROM FL CNTR
CTR DROPSONDE SFC WIND 150 / 5 KT
;

[Hammy]

AF vortex message.

URNT12 KNHC 022021
VORTEX DATA MESSAGE AL012014
A. 02/20:03:50Z
B. 29 deg 42 min N
079 deg 10 min W
C. 850 mb 1354 m
D. 67 kt
E. 070 deg 18 nm
F. 146 deg 71 kt
G. 068 deg 20 nm
H. 992 mb
I. 14 C / 1526 m
J. 20 C / 1525 m
K. 16 C / NA
L. Open NW
M. E30/34/25
N. 12345 / 08
O. 0.02 / 1.5 nm
P. AF301 0601A ARTHUR OB 10
MAX FL WIND 71 KT 068 / 20 NM 19:57:00Z
MAX FL TEMP 19 C 075 / 6 NM FROM FL CNTR
CTR DROPSONDE SFC WIND 150 / 5 KT
;

is that 67kt at the surface?

[somethingfunny]

How high does a storm surge need to be along the Outer Banks before it goes from an inconvenient roadblock to a life-threatening danger? I recall plenty of bad surges that tore up Route 12 and damaged homes with a few feet of water. I can't find much information online about historical surges specifically in the Outer Banks, but as far as I can recall the Outer Banks hasn't experienced a truly catastrophic storm surge.

Of course they could get one, but I think it would have to be a storm much larger and stronger than Arthur is. So with that said, since evacuation seems implausible people should know where the highest ground they can park their vehicles is and hunker down.... and it would be nice to know just how high that surge can get before lives are put into imminent danger.

[Syx6sic]

I can't remember a tropical storm having this clear of an eye. If it is not a hurricane now, it should be soon if trends continue:

http://i62.tinypic.com/2lk5el4.jpg

found this info on wikipdia kinda seems like whats going on now
An eye-like structure is often found in intensifying tropical cyclones. Similar to the eye seen in hurricanes or typhoons, it is a circular area at the circulation center of the storm in which convection is absent. These eye-like features are most normally found in intensifying tropical storms and hurricanes of Category 1 strength on the Saffir-Simpson scale. For example, an eye-like feature was found in Hurricane Beta when the storm had maximum wind speeds of only 80 km/h (50 mph), well below hurricane force.[24] The features are typically not visible on visible wavelengths or infrared wavelengths from space, although they are easily seen on microwave satellite imagery.[25] Their development at the middle levels of the atmosphere is similar to the formation of a complete eye, but the features might be horizontally displaced due to vertical wind shear
http://en.wikipedia.org/wiki/Hurricane_Beta

[Aric Dunn]

from both jax and melboune radar.. it may be trying to tighten up convection wrapping closer to the center.

[xironman]

Overshooting cloud tops approaching d-min, 4mb pressure drop and a 6C temp difference between the eye and storm. Seems like he finally has it going on.

[supercane4867]

AF vortex message.

URNT12 KNHC 022021
VORTEX DATA MESSAGE AL012014
A. 02/20:03:50Z
B. 29 deg 42 min N
079 deg 10 min W
C. 850 mb 1354 m
D. 67 kt
E. 070 deg 18 nm
F. 146 deg 71 kt
G. 068 deg 20 nm
H. 992 mb
I. 14 C / 1526 m
J. 20 C / 1525 m
K. 16 C / NA
L. Open NW
M. E30/34/25
N. 12345 / 08
O. 0.02 / 1.5 nm
P. AF301 0601A ARTHUR OB 10
MAX FL WIND 71 KT 068 / 20 NM 19:57:00Z
MAX FL TEMP 19 C 075 / 6 NM FROM FL CNTR
CTR DROPSONDE SFC WIND 150 / 5 KT
;

is that 67kt at the surface?

D stands for Estimated Maximum Surface Wind

[Hammy]

I think this can safely be called an eye as the article essentially states an eye-like feature is vertically displaced from the LLC whereas this seems pretty stacked.

[Aric Dunn]

might get a center pass from noaa on the next set.

[xironman]

How high does a storm surge need to be along the Outer Banks before it goes from an inconvenient roadblock to a life-threatening danger? I recall plenty of bad surges that tore up Route 12 and damaged homes with a few feet of water. I can't find much information online about historical surges specifically in the Outer Banks, but as far as I can recall the Outer Banks hasn't experienced a truly catastrophic storm surge.

Of course they could get one, but I think it would have to be a storm much larger and stronger than Arthur is. So with that said, since evacuation seems implausible people should know where the highest ground they can park their vehicles is and hunker down.... and it would be nice to know just how high that surge can get before lives are put into imminent danger.

From what I have seen the OBX is much more prone to sound side flooding than storm surge. Think of the way lake Pontchartrain effects New Orleans, Pamlico Sound is shallow and large and greatly effected by the wind.

[northjaxpro]

Just about a hurricane. Arthur looks pretty good right now. I am inclined to believe in a few minutes we will get the word from NHC officially that this will be upgraded to a hurricane with the most recent vortex message indicated sustained 67 kt if that is not an error.