The threat to SE Texas from TS Harvey has increased dramatically overnight and this morning. Harvey is currently rapidly intensifying at a rate of over 2mb per hour. It is on the cusp of becoming a hurricane. It has a closed eye and nearly ideal structure and is moving slowly over extremely warm water.
The latest NHC advisory predicts this will be a Category 3 hurricane at landfall tomorrow evening. The rule of thumb is to always expect one full category greater than forecast, so folks in SE Texas should be preparing for a Cat. 4.
Worse yet, this storm is forecast to be moving very slowly at landfall. It may stall on the coast and/or move NE to NNE up the coast. And this storm has lots of moisture. There will be large parts of the coast to possibly 30 to 50 miles inland that have on the order of 2 feet of rain or more. This is a critical, life-threatening flood potential.
There is very little time. If you are on a barrier island anywhere along the Texas coast except maybe the very southern end, you need to evacuate tonight. Tomorrow morning might, if there’s absolutely no other choice, still possible but you’ll be risking getting caught in traffic while a major hurricane approaches. The more people get out tonight, the better for everyone in terms of safety.
If you are relatively near the coast on the mainland, you need to consider evacuating tonight if you are not certain you can manage for a week or two without much if any outside help. Expect extended power outages. Expect roads that are difficult if not impossible to get through, at least for a few days.
I always hope for the best but prepare for the worst. And folks, the worst is really, really serious this time.
To all in SE Texas, be safe and make your decisions and preparations today. Don’t leave it to the last minute. That’s how people die in these events.
Thursday, Aug 24, 2017 · 3:29:24 PM +00:00
·
jrooth
From the NHC advisory:
BULLETIN
Tropical Storm Harvey Advisory Number 16
NWS National Hurricane Center Miami FL
AL0920171000 AM CDT Thu Aug 24 2017
...HARVEY QUICKLY STRENGTHENING AND FORECAST TO BE A MAJOR HURRICANE WHEN IT APPROACHES THE MIDDLE TEXAS COAST......LIFE-THREATENING STORM SURGE AND FRESHWATER FLOODING EXPECTED…
Thursday, Aug 24, 2017 · 4:42:22 PM +00:00
·
jrooth
Latest center pass by recon had an extrapolated pressure of 979.6 mb. SFMR wind measurement for that reading was 20 kt so it’s fair to say central pressure problby down to 979mb.
That means it’s continuing its 2mb/hour rapid deepening.
Thursday, Aug 24, 2017 · 5:06:31 PM +00:00
·
jrooth
Special advisory: upgraded to hurricane
Hurricane Harvey Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL092017
1200 PM CDT Thu Aug 24 2017
...HARVEY STRENGTHENS TO A HURRICANE WITH 80-MPH WINDS...
Data from an Air Force Reserve Hurricane Hunter aircraft indicate
that Harvey has intensified to a hurricane, with maximum sustained
winds of 80 mph (130 km/h).
A Special Advisory will be issued by 1 PM CDT (1800 UTC) in lieu
of the intermediate advisory to update the intensity forecast.
SUMMARY OF 1200 PM CDT...1700 UTC...INFORMATION
----------------------------------------------
LOCATION...24.3N 93.5W
ABOUT 340 MI...550 KM SE OF CORPUS CHRISTI TEXAS
ABOUT 335 MI...540 KM SSE OF PORT OCONNOR TEXAS
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NNW OR 335 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...981 MB...28.97 INCHES
Thursday, Aug 24, 2017 · 5:49:16 PM +00:00
·
jrooth
1pm CDT special advisory:
BULLETIN
Hurricane Harvey Special Advisory Number 17
NWS National Hurricane Center Miami FL AL092017
100 PM CDT Thu Aug 24 2017
...HARVEY RAPIDLY INTENSIFYING...
...PREPARATIONS ALONG THE MIDDLE TEXAS COAST SHOULD BE RUSHED TO
COMPLETION TODAY...
SUMMARY OF 100 PM CDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...24.4N 93.6W
ABOUT 335 MI...540 KM SE OF CORPUS CHRISTI TEXAS
ABOUT 325 MI...525 KM SSE OF PORT OCONNOR TEXAS
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NNW OR 335 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...979 MB...28.91 INCHES
(emphasis mine)
Thursday, Aug 24, 2017 · 6:01:45 PM +00:00
·
jrooth
1. Harvey has intensified rapidly, and is forecast to be a major
hurricane at landfall, bringing life-threatening storm surge,
rainfall, and wind hazards to portions of the Texas coast.
Preparations to protect life and property should be completed by
tonight, as tropical-storm-force winds will first arrive in the
hurricane and storm surge warning areas on Friday.
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.
3. Life-threatening flooding is expected across much of the Texas
coast from heavy rainfall of 12 to 20 inches, with isolated amounts
as high as 30 inches, from Friday through early next week. 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.