ATL: HARVEY - Post-Tropical - Discussion

[SouthDadeFish]

The center will continue to wobble cyclonically around the larger eyewall until the EWRC finishes. Pay attention the long-term motion of those fixes. That's closer to the motion of the outer eyewall and main vortex.

[pcolaman]

Looks like Victoria will be first land fall area

[txwatcher91]

It looks like the right inner eyewall is attempting to merge with the larger one, and the larger one seems to be slowly contracting.

[vortex100]

I am glad I am off work the next couple of days so I can watch the storm progress at my leisure. 00Z ECMWF scary as all get out.

[Tree]

I hope I'm doing this correctly. This is a link to a site containing a list of Tx coastal beach cams. http://www.al.com/news/index.ssf/2017/0 ... ch_ha.html

[Aric Dunn]

anyone got the VDM ?

[MississippiWx]

um that's a huge wobble...recon fixed....NNW brings it closer to more population

Center will move erratically until inner eye wall collapses.

[Red eye]

Motion looks almost due North now on the radar. This is an impressive Hurricane.

[Tireman4]

Looks like Victoria will be first land fall area

Victoria?

[Aric Dunn]

latest radar images.. the inner eye has nearly completely opened up and either merged the outer contracting eyewall or collapsed..and becoming very intense.

[bvigal]

How much longer do we have until landfall? If Harvey hits land in the middle of the ERC, will the effects be lessened? Or has the damage already been done, when the wind field expanded?

"Landfall" is a misunderstood, thus potentially dangerous term. Many people think the time of EYE reaching land is how much time they have to begin feeling the worst of the storm. In reality, "landfall" is when the CENTER of the storm reaches land, HALFWAY through the worst of the weather! Much better to talk about when is the last time it's safe to evacuate (2 feet of water on any road ends possibility of escape in car), run to store (shelves empty?), get fuel (pumps empty?), finish boarding up, and be safely hunkered down, which is HOURS before landfall. That time differs by area, but it is the most important time to learn. For some, it's already arrived.

[ROCK]

idk if that was a wobble or what...want another fix...that is concerning..

[MississippiWx]

Looking at radar, that inner eye wall is about to collapse.

[MississippiWx]

idk if that was a wobble or what...want another fix...that is concerning..

Yeah, northward wobbles do mean a lot if they are over an extended period.

[Red eye]

My sister's employer (out of galveston) said "Full day on Friday and Monday". They are on Galveston island but I still don't get it. Shriner's and UTMB.

[Aric Dunn]

Looking at radar, that inner eye wall is about to collapse.

Its close, and merging with outer contracting eyewall

[txwatcher91]

idk if that was a wobble or what...want another fix...that is concerning..

Yeah, northward wobbles do mean a lot if they are over an extended period.

A north wobble would likely take this north of Corpus Christi, which would be better right? Or would it bring other high population areas into the possible landfall zone if it goes more north?

[tolakram]

Saved radar loop

[Blinhart]

My sister's employer (out of galveston) said "Full day on Friday and Monday". They are on Galveston island but I still don't get it. Shriner's and UTMB.

If I was your sister I wouldn't be going in, especially being on Galveston Island could be cut off completely by Monday. Today isn't that worrisome but after today it will be just getting worse until Harvey gets out sometime late next week.

[cycloneye]

BULLETIN
Hurricane Harvey Advisory Number 21
NWS National Hurricane Center Miami FL AL092017
1000 AM CDT Fri Aug 25 2017

...OUTER RAINBAND FROM HARVEY SWIPING THE LOWER AND MIDDLE TEXAS
COASTS...
...CATASTROPHIC FLOODING EXPECTED ACROSS PORTIONS OF SOUTHERN AND
SOUTHEASTERN TEXAS...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...26.7N 96.0W
ABOUT 115 MI...185 KM SE OF CORPUS CHRISTI TEXAS
ABOUT 120 MI...195 KM SSE OF PORT OCONNOR TEXAS
MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...947 MB...27.97 INCHES
------------------------------------------------------------------------



Hurricane Harvey Discussion Number 21
NWS National Hurricane Center Miami FL AL092017
1000 AM CDT Fri Aug 25 2017

Multiple observing platforms indicate that Harvey's structure is
evolving this morning. The hurricane has developed concentric
eyewalls, as observed in data from the WSR-88D Doppler radars in
Brownsville and Corpus Christi, and an Air Force Reserve Hurricane
Hunter plane reported double wind maxima with diameters of 12 and
28 n mi. The aircraft data indicate that the central pressure has
continued to fall--now down to 947 mb--but the maximum winds have
not increased further. This discrepancy is not surprising given
hurricane's current structure.

Intensity forecasts become complicated once a hurricane develops
concentric eyewalls, and fluctuations in intensity become more
likely. If an eyewall replacement occurs, then Harvey's intensity
could decrease a bit while at the same time the overall wind field
increases in size. However, the hurricane remains in an environment
for intensification, and strengthening beyond the current intensity
is still possible before the center reaches land. But in the end,
the hurricane's exact intensity at landfall does not change the
fact that catastrophic flooding due to a prolonged period of heavy
rainfall and/or storm surge is expected at the coast and well inland
across much of southern and southeastern Texas. Slow weakening is
expected after Harvey crosses the coast since the center is not
expected to move very far inland, and the cyclone is likely to
maintain tropical storm status through Wednesday.

Harvey has not quite begun to slow down, and the initial motion
estimate is 315/9 kt. Strong mid-level ridging building over the
western United States is still expected to impede Harvey's forward
motion in the coming days, and the track guidance continues to show
the hurricane meandering or stalling near or just inland of the
Texas coast in 36-48 hours. Harvey could begin moving slowly
eastward on days 4 and 5 due to the influence of a mid-level
shortwave trough digging southward over the upper Midwest, but at
this time it is too early to say whether the center will definitely
re-emerge over the northwestern Gulf of Mexico.

Key Messages:

1. Harvey is expected to be a major hurricane when it makes landfall
tonight, bringing life-threatening storm surge, rainfall, and wind
hazards to portions of the Texas coast. Preparations should be
rushed to completion in the warning areas as tropical-storm-force
winds are arriving on the coast, and conditions will continue to
deteriorate through the rest of today and tonight.

2. A Storm Surge Warning is in effect for much of the Texas coast.
Life-threatening storm surge flooding could reach heights of 6 to 12
feet above ground level at the coast between the north entrance of
the Padre Island National Seashore and Sargent. For a depiction of
areas at risk, see the Storm Surge Watch/Warning Graphic at
hurricanes.gov. Due to the slow motion of Harvey and a prolonged
period of onshore flow, water levels will remain elevated for
several days.

3. Catastrophic and life-threatening flooding is expected across the
middle and upper Texas coast from heavy rainfall of 15 to 25 inches,
with isolated amounts as high as 35 inches, through Wednesday.
Please refer to products from your local National Weather Service
office and the NOAA Weather Prediction Center for more information
on the flooding hazard.

4. The Potential Storm Surge Flooding Map is available on the NHC
website. This product depicts a reasonable worst-case scenario -
the amount of inundation that has a 10 percent chance of being
exceeded at each individual location. This map best represents
the flooding potential in those locations within the watch and
warning areas.

FORECAST POSITIONS AND MAX WINDS

INIT 25/1500Z 26.7N 96.0W 95 KT 110 MPH
12H 26/0000Z 27.6N 96.8W 105 KT 120 MPH
24H 26/1200Z 28.4N 97.3W 90 KT 105 MPH...INLAND
36H 27/0000Z 28.8N 97.5W 70 KT 80 MPH...INLAND
48H 27/1200Z 28.9N 97.6W 55 KT 65 MPH...INLAND
72H 28/1200Z 28.3N 96.8W 35 KT 40 MPH...INLAND
96H 29/1200Z 28.5N 95.5W 40 KT 45 MPH...OVER WATER
120H 30/1200Z 30.0N 94.5W 40 KT 45 MPH...INLAND

$$
Forecaster Berg

NNNN