ATL: HARVEY - Post-Tropical - Discussion

[NDG]

I think the LLC tugged itself very close to the deep convection during the past couple of hours.

[Meteorcane]

Lightning in a TC can indicate either dry air in the core or that it is organizing and producing some deep convection. I would say it is probably due to a little dry air being mixed out and the recent explosion of deep convection.

That seems to be the case.

Out of curiosity what is the reasoning behind dry air ingestion and increased lightning? Increased cooling/destabilization of the mid-upper lvl profile due to evaporative cooling/sublimation resulting in increased updraft strength?

[tolakram]

Big blowup of convection happening over the center.

http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=conus&x=4606.5&y=6320.5&z=3&im=18&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&p%5B0%5D=1&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&s=rammb-slider

[TeamPlayersBlue]

Still pretty weak even for a TD but gathering itself. When it gets closer to 1000, then we can start to expect some decent intensification. The elongated low has been holding it back.

[Nimbus]

Watch that convection explosion on the 8.4 setting.
With the central surface pressure already starting to plummet this is going to be bad news.
Only thing we can hope for is something like a trough interaction or dry air ingestion offshore before landfall.

[TheStormExpert]

 https://twitter.com/philklotzbach/status/900423061836447744

[tolakram]

30 frame loop

https://weather.msfc.nasa.gov/cgi-bin/get-abi?satellite=GOESEastconusband02&lat=22&lon=-92&width=1000&height=800&zoom=2&type=Animation&numframes=30&quality=92

[NDG]

ASCAT from earlier this morning confirms that the circulation on the NE quadrant is indeed a bit elongated.

[ROCK]

that ASCAT is from this morning though...way better defined and stacked now than before. I am waiting for DMAX for this to take hold.

[Sanibel]

Much better than yesterday...Are they underestimating this or are they gambling on dry air?

[GCANE]

Right on the bulls-eye

[chaser1]

This slower movement is helping it organize a little better as it is distancing itself from the ULL to its NW. It needs to get moving soon, or this could get bad quickly.

If it stalls and sits there for too long though upwelling could become an issue...

Doubtful that up-welling will be any type of issue here. Mostly because of the deeper very warm SST's ahead. I see an interesting monkey-wrench that a bit longer of a delay to a northwest motion could cause. Perhaps a small ripple in timing being an added variable that could possibly cause Harvey to remain closer to the coast (or even offshore), before turning more northward and eventually ENE'ward toward Louisiana?

[chaser1]

I do see dry air to the west but this large system is really getting nicely organized in spite of that. With the increasingly organized convergence occurring, there seems little doubt that Harvey is already easily overcoming any try capping that some dry air might have caused earlier today. Looking at those cloud tops, I'd say it could well be on its way toward creating a tighter more defined inner core by tomm. a.m. I'll frankly be surprised if pressures are not down by at least 5 or 6 millibars by then.

[Blinhart]

Well the Sheriff of Acadia Parish has said to expect 10 to 20 inches of rain in a 4 day period, as of right now. He is telling everyone to keep an eye on this as it could get even worse.

All I have to say if we get 1 to 2 days of rain before a possible Cat 2 or 3 hurricane comes ashore we will see many trees and major flooding around here.

[GCANE]

Can see the cirrus layers on AVN depicted by the shades of orange.

[cycloneye]

URGENT - IMMEDIATE BROADCAST REQUESTED
Harvey Local Watch/Warning Statement/Intermediate Advisory Number 12A
National Weather Service Brownsville TX AL092017
220 PM CDT Wed Aug 23 2017

TXZ257-240330-
/O.CON.KBRO.TR.A.1009.000000T0000Z-000000T0000Z/
Coastal Cameron-
220 PM CDT Wed Aug 23 2017

...TROPICAL STORM WATCH REMAINS IN EFFECT...

* LOCATIONS AFFECTED
- South Padre Island
- Port Isabel

* WIND
- LATEST LOCAL FORECAST: Below tropical storm force wind
- Peak Wind Forecast: 10-20 mph with gusts to 30 mph

- CURRENT THREAT TO LIFE AND PROPERTY: Moderate
- The wind threat has remained nearly steady from the
previous assessment.
- Emergency plans should include a reasonable threat for
strong tropical storm force wind of 58 to 73 mph.
- To be safe, earnestly prepare for the potential of
significant wind impacts. Remaining efforts to secure
properties should now be brought to completion.
- Dangerous wind is possible. Failure to adequately shelter
may result in injury. Move to safe shelter before the wind
becomes hazardous.

- POTENTIAL IMPACTS: Significant
- Some damage to roofing and siding materials, along with
damage to porches, awnings, carports, and sheds. A few
buildings experiencing window, door, and garage door
failures. Mobile homes damaged, especially if unanchored.
Unsecured lightweight objects become dangerous projectiles.
- Several large trees snapped or uprooted, but with greater
numbers in places where trees are shallow rooted. Several
fences and roadway signs blown over.
- Some roads impassable from large debris, and more within
urban or heavily wooded places. A few bridges, causeways,
and access routes impassable.
- Scattered power and communications outages, but more
prevalent in areas with above ground lines.

* STORM SURGE
- No storm surge inundation forecast

- CURRENT THREAT TO LIFE AND PROPERTY: None
- The storm surge threat has remained nearly steady from the
previous assessment.
- Emergency planning for this event need not include a threat
for storm surge flooding. The ground will remain largely
unflooded from surge water or only have spots minimally
affected by surge water encroachment. Surf conditions may
still be rough with some beach erosion. Stronger than
normal rip currents may also be present.
- Little to no preparations needed to guard against storm
surge flooding at this time.
- Ensure readiness for the next storm surge event.

- POTENTIAL IMPACTS: Little to None
- Little to no potential impacts from storm surge flooding.

* FLOODING RAIN
- LATEST LOCAL FORECAST:
- Peak Rainfall Amounts: Additional 3-5 inches, with locally
higher amounts

- CURRENT THREAT TO LIFE AND PROPERTY: Elevated
- The flooding rain threat has remained nearly steady from
the previous assessment.
- Emergency plans should include a reasonable threat for
minor flooding where peak rainfall totals are near amounts
conducive for localized flash flooding and rapid inundation.
- To be safe, prepare for the potential of limited flooding
rain impacts.
- Localized flooding is possible. If flood related watches
and warnings are issued, heed recommended actions.

- POTENTIAL IMPACTS: Limited
- Localized rainfall flooding may prompt a few evacuations.
- Rivers and tributaries may quickly rise with swifter
currents. Small streams, creeks, canals, arroyos, and
ditches may become swollen and overflow in spots.
- Flood waters can enter a few structures, especially in
usually vulnerable spots. A few places where rapid ponding
of water occurs at underpasses, low-lying spots, and poor
drainage areas. Several storm drains and retention ponds
become near-full and begin to overflow. Some brief road and
bridge closures.

* TORNADO
- LATEST LOCAL FORECAST:
- Situation is unfavorable for tornadoes

- CURRENT THREAT TO LIFE AND PROPERTY: None
- The tornado threat has remained nearly steady from the
previous assessment.
- Emergency plans need not include a threat for tornadoes.
Showers and thunderstorms with strong gusty winds may still
occur.
- Little to no preparations needed to guard against tropical
tornadoes.
- Ensure readiness for the next tropical tornado event.

- POTENTIAL IMPACTS: Little to None
- Little to no potential impacts from tornadoes.

* FOR MORE INFORMATION:
- http://ready.gov/hurricanes

$$

TXZ256-240330-
/O.CON.KBRO.TR.A.1009.000000T0000Z-000000T0000Z/
Coastal Willacy-
220 PM CDT Wed Aug 23 2017

...TROPICAL STORM WATCH REMAINS IN EFFECT...

* LOCATIONS AFFECTED
- Port Mansfield

* WIND
- LATEST LOCAL FORECAST: Below tropical storm force wind
- Peak Wind Forecast: 25-35 mph with gusts to 45 mph

- CURRENT THREAT TO LIFE AND PROPERTY: Moderate
- The wind threat has remained nearly steady from the
previous assessment.
- Emergency plans should include a reasonable threat for
strong tropical storm force wind of 58 to 73 mph.
- To be safe, earnestly prepare for the potential of
significant wind impacts. Remaining efforts to secure
properties should now be brought to completion.
- Dangerous wind is possible. Failure to adequately shelter
may result in injury. Move to safe shelter before the wind
becomes hazardous.

- POTENTIAL IMPACTS: Significant
- Some damage to roofing and siding materials, along with
damage to porches, awnings, carports, and sheds. A few
buildings experiencing window, door, and garage door
failures. Mobile homes damaged, especially if unanchored.
Unsecured lightweight objects become dangerous projectiles.
- Several large trees snapped or uprooted, but with greater
numbers in places where trees are shallow rooted. Several
fences and roadway signs blown over.
- Some roads impassable from large debris, and more within
urban or heavily wooded places. A few bridges, causeways,
and access routes impassable.
- Scattered power and communications outages, but more
prevalent in areas with above ground lines.

* STORM SURGE
- No storm surge inundation forecast

- CURRENT THREAT TO LIFE AND PROPERTY: None
- The storm surge threat has remained nearly steady from the
previous assessment.
- Emergency planning for this event need not include a threat
for storm surge flooding. The ground will remain largely
unflooded from surge water or only have spots minimally
affected by surge water encroachment. Surf conditions may
still be rough with some beach erosion. Stronger than
normal rip currents may also be present.
- Little to no preparations needed to guard against storm
surge flooding at this time.
- Ensure readiness for the next storm surge event.

- POTENTIAL IMPACTS: Little to None
- Little to no potential impacts from storm surge flooding.

* FLOODING RAIN
- LATEST LOCAL FORECAST:
- Peak Rainfall Amounts: Additional 3-5 inches, with locally
higher amounts

- CURRENT THREAT TO LIFE AND PROPERTY: Elevated
- The flooding rain threat has remained nearly steady from
the previous assessment.
- Emergency plans should include a reasonable threat for
minor flooding where peak rainfall totals are near amounts
conducive for localized flash flooding and rapid inundation.
- To be safe, prepare for the potential of limited flooding
rain impacts.
- Localized flooding is possible. If flood related watches
and warnings are issued, heed recommended actions.

- POTENTIAL IMPACTS: Limited
- Localized rainfall flooding may prompt a few evacuations.
- Rivers and tributaries may quickly rise with swifter
currents. Small streams, creeks, canals, arroyos, and
ditches may become swollen and overflow in spots.
- Flood waters can enter a few structures, especially in
usually vulnerable spots. A few places where rapid ponding
of water occurs at underpasses, low-lying spots, and poor
drainage areas. Several storm drains and retention ponds
become near-full and begin to overflow. Some brief road and
bridge closures.

* TORNADO
- LATEST LOCAL FORECAST:
- Situation is unfavorable for tornadoes

- CURRENT THREAT TO LIFE AND PROPERTY: None
- The tornado threat has remained nearly steady from the
previous assessment.
- Emergency plans need not include a threat for tornadoes.
Showers and thunderstorms with strong gusty winds may still
occur.
- Little to no preparations needed to guard against tropical
tornadoes.
- Ensure readiness for the next tropical tornado event.

- POTENTIAL IMPACTS: Little to None
- Little to no potential impacts from tornadoes.

* FOR MORE INFORMATION:
- http://ready.gov/hurricanes

$$

TXZ251-240330-
/O.NEW.KBRO.SS.A.1009.170823T1920Z-000000T0000Z/
/O.CON.KBRO.HU.A.1009.000000T0000Z-000000T0000Z/
Kenedy-
220 PM CDT Wed Aug 23 2017

...STORM SURGE WATCH IN EFFECT...
...HURRICANE WATCH REMAINS IN EFFECT...

A Storm Surge Watch means life-threatening inundation levels are
possible somewhere within this area and within the next 48 hours

* LOCATIONS AFFECTED
- Sarita
- King Ranch

* WIND
- LATEST LOCAL FORECAST: Below tropical storm force wind
- Peak Wind Forecast: 10-20 mph with gusts to 30 mph

- CURRENT THREAT TO LIFE AND PROPERTY: Moderate
- The wind threat has remained nearly steady from the
previous assessment.
- Emergency plans should include a reasonable threat for
strong tropical storm force wind of 58 to 73 mph.
- To be safe, earnestly prepare for the potential of
significant wind impacts. Remaining efforts to secure
properties should now be brought to completion.
- Dangerous wind is possible. Failure to adequately shelter
may result in injury. Move to safe shelter before the wind
becomes hazardous.

- POTENTIAL IMPACTS: Significant
- Some damage to roofing and siding materials, along with
damage to porches, awnings, carports, and sheds. A few
buildings experiencing window, door, and garage door
failures. Mobile homes damaged, especially if unanchored.
Unsecured lightweight objects become dangerous projectiles.
- Several large trees snapped or uprooted, but with greater
numbers in places where trees are shallow rooted. Several
fences and roadway signs blown over.
- Some roads impassable from large debris, and more within
urban or heavily wooded places. A few bridges, causeways,
and access routes impassable.
- Scattered power and communications outages, but more
prevalent in areas with above ground lines.

* STORM SURGE
- LATEST LOCAL FORECAST: Life-threatening storm surge possible
- Peak Storm Surge Inundation: The potential for 2-4 feet
above ground somewhere within surge prone areas
- Window of concern: Begins Friday morning

- CURRENT THREAT TO LIFE AND PROPERTY: Moderate
- The storm surge threat has remained nearly steady from the
previous assessment.
- Emergency planning should include a reasonable threat for
dangerous storm surge flooding of greater than 3 feet above
ground.
- To be safe, earnestly prepare for the potential of
significant storm surge flooding impacts. Evacuation
efforts should now be underway.
- Life-threatening inundation is possible. Failure to heed
evacuation orders may result in serious injury or loss of
life. Leave if evacuation orders are given for your area.
Consider voluntary evacuation if recommended. Poor
decisions may needlessly risk lives.

- POTENTIAL IMPACTS: Significant
- Areas of inundation with storm surge flooding accentuated
by waves. Damage to several buildings, mainly near the
coast.
- Sections of near-shore escape routes and secondary roads
become weakened or washed out, especially in usually
vulnerable low spots.
- Major beach erosion with heavy surf breaching dunes. Strong
and numerous rip currents.
- Moderate damage to marinas, docks, boardwalks, and piers.
Several small craft broken away from moorings, especially
in unprotected anchorages.

* FLOODING RAIN
- LATEST LOCAL FORECAST:
- Peak Rainfall Amounts: Additional 3-5 inches, with locally
higher amounts

- CURRENT THREAT TO LIFE AND PROPERTY: Elevated
- The flooding rain threat has remained nearly steady from
the previous assessment.
- Emergency plans should include a reasonable threat for
minor flooding where peak rainfall totals are near amounts
conducive for localized flash flooding and rapid inundation.
- To be safe, prepare for the potential of limited flooding
rain impacts.
- Localized flooding is possible. If flood related watches
and warnings are issued, heed recommended actions.

- POTENTIAL IMPACTS: Limited
- Localized rainfall flooding may prompt a few evacuations.
- Rivers and tributaries may quickly rise with swifter
currents. Small streams, creeks, canals, arroyos, and
ditches may become swollen and overflow in spots.
- Flood waters can enter a few structures, especially in
usually vulnerable spots. A few places where rapid ponding
of water occurs at underpasses, low-lying spots, and poor
drainage areas. Several storm drains and retention ponds
become near-full and begin to overflow. Some brief road and
bridge closures.

* TORNADO
- LATEST LOCAL FORECAST:
- Situation is unfavorable for tornadoes

- CURRENT THREAT TO LIFE AND PROPERTY: None
- The tornado threat has remained nearly steady from the
previous assessment.
- Emergency plans need not include a threat for tornadoes.
Showers and thunderstorms with strong gusty winds may still
occur.
- Little to no preparations needed to guard against tropical
tornadoes.
- Ensure readiness for the next tropical tornado event.

- POTENTIAL IMPACTS: Little to None
- Little to no potential impacts from tornadoes.

* FOR MORE INFORMATION:
- http://ready.gov/hurricanes
- http://co.kenedy.tx.us

[hohnywx]

Texas A&M University in Corpus Christi has announced an evacuation of campus beginning Thursday:

http://safety.tamucc.edu/Hurricane.html

[GCANE]

Looks like cork popped.
BoC Buoy is doing the nose dive.
Large ass tower firing off now.

[GCANE]

Looks like a nuclear bomb on VIS

[vbhoutex]

30 frame loop

https://weather.msfc.nasa.gov/cgi-bin/get-abi?satellite=GOESEastconusband02&lat=22&lon=-92&width=1000&height=800&zoom=2&type=Animation&numframes=30&quality=92

And unless I am crazy(hold the comments) storms are firing right over the center. I don't like seeing that, but it is to be expected with the parameters currently in place.