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Harvey is a Tropical Depression again, hurricane warnings have been issued for the Texas coast. Models still differ on intensity but we have a few cat 2/3 runs still there. 

Big problem here is rainfall, Texas is looking at catastrophic flooding from Harvey (will definitely be retired) as the folk of Texas will be measuring their rainfall in feet rather than inches. 

As of the last update, pressure down to 1003mb. 

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Looks like Harvey is over its center issues. Between the 10pm and 9am updates pressure dropped from 1003mb to 995mb (Euro forecast is already a bust since it never gets it below 1001mb) and the center relocated north west under heavier convection. The response is that Harvey has increased windspeed to 45mph. 

GFS this morning went bananas and had Harvey at cat 3 (~950mb) in 48 hours although the stall once again has them rowing boats for the next week.

Recon is due in again pretty soon. 

SHIPS forecast for rapid intensification is at 53% for 25KT in 24 hours which would make Harvey a hurricane tomorrow morning. Personally (given the improvement in structure above overnight), i'm not sure we'll have to wait that long. 

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Holy frack! The more data gets sent in, the stronger the GFS is. 

Cat 4 from the GFS6z!!!

gfs_mslp_wind_scus_7.png

The US may actually end it's major hurricane drought (12 years) in an absolutely catastrophic manner. 

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8 minutes ago, summer blizzard said:

Holy frack! The more data gets sent in, the stronger the GFS is. 

Cat 4 from the GFS6z!!!

gfs_mslp_wind_scus_7.png

The US may actually end it's major hurricane drought (12 years) in an absolutely catastrophic manner. 

The gfs was the least enthusiastic up to yesterday but certainly upgraded the storm today. I notice there is a shift towards Mexico though.

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Harvey will need its own thread folks. Just like Matthew last year, it's clear that Harvey is going through ri at the . raw Dvorak t numbers are rising sharply and already indicate he's a hurricane. At 65kts. 

Pefectly vertically stacked and a strong inflow. 

Latest gfs is very believable and a strong slow moving major hurricane is very likely. 

Winds will be tight with a smallest extreme wind field so exact track will be crucial. 

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Pressure has fallen to 985mb a fall of 10mb in just 4 hrs so clear ri. 

As expected winds are a little slower to respond but look to be around 45-50kts. 

06z models firmly put tx and possibly corpus in the line. 

Av shows strong deep very cold convection around the eye wall. 

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CDO forming with a symmetrical core. 

avn0-lalo.gif

Definitely a 60mph+ TS.

Recon are in now, given that they found 1001mb at 4am our time i wonder what they'll find now (about 9 hours after).

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1 minute ago, Iceberg said:

Pressure has fallen to 985mb a fall of 10mb in just 4 hrs so clear ri. 

As expected winds are a little slower to respond but look to be around 45-50kts. 

06z models firmly put tx and possibly corpus in the line. 

Av shows strong deep very cold convection around the eye wall. 

Oh boy, this is going to be good. 

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4 minutes ago, summer blizzard said:

Oh boy, this is going to be good. 

60+kt flight winds in the se quad which is stronger than I would have thought. 

The strength could well pull him further north. 

This is a real problem hurricane for Texas. It's spun up insanely quickly  with little time for landfall and very little news coverage. 

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Recon confirm 55mph on the first pass. 

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BULLETIN
Tropical Storm Harvey Intermediate Advisory Number 15A
NWS National Hurricane Center Miami FL       AL092017
700 AM CDT Thu Aug 24 2017

...AIR FORCE HURRICANE HUNTER PLANE FINDS HARVEY STRENGTHENING...


SUMMARY OF 700 AM CDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...23.8N 93.0W
ABOUT 380 MI...615 KM SE OF PORT OCONNOR TEXAS
ABOUT 335 MI...540 KM SE OF PORT MANSFIELD TEXAS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NNW OR 345 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...986 MB...29.12 INCHES
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Anybody have the Depression to Hurricane record on hand?

Also some of those Wilma pressure record falls?

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Quick release update from nhc just issued. Confirming the above and putting winds at 60mph. 

The more I look at the pressentation the more it looks like a potential cat 4

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Just now, Iceberg said:

Quick release update from nhc just issued. Confirming the above and putting winds at 60mph. 

The more I look at the pressentation the more it looks like a potential cat 4

About 48 hours until landfall so even at a pedestrian pace of intensification we end up about ~960mb, 105mph (cat 2). At its current pace though we are looking at there being no limit. 

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Convection increasing, cloud tops cooling and outflow becoming better organised, wouldn't be surprised to see an eye in the microwave imagery in the next hour. Looks like Harvey will become a hurricane about a day before models and NHC anticipated - I'm sure if the 12z/18z suites are initialized at hurricane intensity they will be quite sobering. I think Wilmas max pressure drop was about 96mb in 24 hours.

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Worth remembering convection will increase quickly with 31-32 ssts over the path. 

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Closed eyewall, Harvey likely now a hurricane. 

 

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Hard to comprehend. That’s the average annual rainfall London has - latest model output suggest a rapid intensification to a Major Hurricane status to further the woes.  

 

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Posted (edited)

Seems like it will deepen beyond a cat 1 now, the way updates are evolving Harvey so rapidly it's hard to keep up! What looked like mainly a major/disastrous inland flooding event could also have impacts of damaging winds and devasting storm surge too if it reaches at Cat 3 or worse, as some seem to be now hinting at!

https://twitter.com/NHC_Atlantic/status/900735336053178370

https://twitter.com/MJVentrice/status/900735813809471489https://twitter.com/NHC_Atlantic/status/900735336053178370

 

 

Edited by Nick F

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NHC goes with 982mb, 65mph and notes the closed eyewall. 

NHC forecast is now for a hit at 115mph, category 3. 

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