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Be thankful that ULL is out there.

Otherwise we would be dealing with a more serious situation.

The TUTT feature certainly is a saving grace regarding a potentially much more serious situation, but still could bring significant rainfall as it slowly moves toward the NW Gulf Coast and inland.

Shear Over GOM

Jeff Linder Update Weather This Morning...

Good look from GOES 16 this morning of the MCV/surface low in S Central Texas and our area of disturbed weather nearing the Yucatan in the NW Caribbean. What at mess!

It's going to be an interesting early Saturday morning trying to fly out of Texas and a connecting flight scheduled in Charlotte with Florence lurking. Then onto the Caribbean with Isaac a potential threat. Playing pinball with tropical systems. What a way to start a vacay!

Looking at the radar loop, it appears this rain shield may move quite a bit inland.

The Euro run from earlier this morning gives basically all of SETX 5-10” of rain with isolated higher totals possible.

Flood Advisory

Flood Advisory
National Weather Service Houston/Galveston TX
1026 AM CDT MON SEP 10 2018

TXC039-167-101730-
/O.NEW.KHGX.FA.Y.0110.180910T1526Z-180910T1730Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Galveston TX-Brazoria TX-
1026 AM CDT MON SEP 10 2018

The National Weather Service in League City has issued a

* Flood Advisory for...
Galveston County in southeastern Texas...
Northeastern Brazoria County in southeastern Texas...

* Until 1230 PM CDT.

* At 1025 AM CDT, Doppler radar indicated heavy rain due to
thunderstorms. This will cause minor flooding in the advisory area.

* Some locations that will experience flooding include...
League City, Galveston Causeway, Galveston Island West End, Texas
City, Alvin, Dickinson, La Marque, Santa Fe, Hitchcock, Kemah,
Galveston Pier 21, Bayou Vista, Jamaica Beach, Tiki Island,
Hillcrest, Liverpool, San Leon, Scholes Field, Port Bolivar and
Offatts Bayou.

NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 96 HOURS
FORECAST POSITION AT T+ 96 : 25.4N 96.2W

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
12UTC 14.09.2018 25.4N 96.2W WEAK
00UTC 15.09.2018 26.4N 97.4W WEAK LITTLE CHANGE
12UTC 15.09.2018 27.0N 98.9W WEAK LITTLE CHANGE
00UTC 16.09.2018 27.6N 100.1W WEAK LITTLE CHANGE
12UTC 16.09.2018 28.0N 101.3W WEAK LITTLE CHANGE

NWS Houston Update

NWS Flooding Update

Monday Midday Update from Jeff:

Numerous showers and thunderstorms moving inland from the coast this morning with quick bursts of excessive rainfall of 1-3 inches.

So far storms have been moving enough to the keep rainfall rates and totals manageable, but this may begin to change this afternoon into tonight with stronger jet dynamics coming to pay and potentially slower storm motions. Feel the greatest threat area is along and SE of US 59 where the Flash Flood Watch area begins at 100pm today.

Will maintain rainfall amounts of 2-4 inches, but isolated amounts of 6 inches are possible and this could fall in a short period of time both this afternoon and again late tonight into Tuesday morning. It is possible that the heaviest rains remain near the coast like we saw on Labor Day, but there are some indications that areas a bit further inland could see heavy rains.

Main flooding concerns will be street systems, but will need to keep an eye on area bayous and creeks especially with the grounds becoming increasing saturated which will increase run-off rates.

The 12Z GFS suggest at 700 and 850mb, a bit of a circulation attempting to organize as the tropical disturbance in the NW Caribbean nears the Middle Texas Coast at hour 102 (Friday afternoon/evening).

Mesoscale Precipitation Discussion 0818
NWS Weather Prediction Center College Park MD
1205 PM EDT Mon Sep 10 2018

Areas affected...Central and Northeast Texas Coast

Concerning...Heavy rainfall...Flash flooding possible

Valid 101604Z - 102100Z

Summary...Showers and thunderstorms will increase in coverage and
lift onshore through the afternoon. Rainfall of 2-4" is possible
which has the potential to produce flash flooding.

Discussion...A cluster of thunderstorms noted by cooling cloud
tops on GOES-16 IR imagery and regional radar mosaic is expanding
in coverage across the NW Gulf of Mexico. An MCV is implied by
rotation in the radar SW of San Antonio, while a strong shortwave
is digging southward along the NM/TX border. These features in
tandem are helping to drive mid and upper level diffluence across
E TX, which will be further enhanced by a 50kt 300mb jet lifting
NE this afternoon, placing E TX in the favorable right entrance
region to this feature. Although low-level winds are weak, latest
RAP analyzed MLCape is around 1500 J/kg, more than sufficient to
lift surface parcels, which will then be lifted upward by the
synoptic lift implied by the increasing diffluence aloft.

Morning PWATs from upper air soundings at CRP as well as RAP
analysis shows a large area of 2.1 to 2.3 inches flooding into the
TX coast. While these are not extreme values, they are above the
90th percentile for the date which combined with forecast warm
cloud depth approaching 15kft is suggestive of efficient warm rain
processes even in convective elements. This is echoed by HGX
estimated rainfall rates of 1 to 1.5 inches per hour lifting onto
the TX coast, coincident with KDP values of 2-3 deg/Km coincident
with high reflectivity. The convection offshore is likely to
increase in coverage during the next few hours and lift northward.
Although FFG is not exceedingly low, 3-4" in 3 hours, a stripe of
heavier rainfall is likely along and just inland from the coast
where frictional convergence and a low-level theta-e axis merge.
Rainfall of 2-4" is possible across this area as storms move
slowly on 0-6km mean wind of less than 10 kts. This may be
sufficient to produce flash flooding across the area.

Weiss

ATTN...WFO...CRP...HGX...LCH...

NHC Director did a Facebook live update, covers all of them, so not sure where to put it ?

https://www.facebook.com/pg/NWSNHC/posts

Flash Flood Versus Warning..PSA

We have 95L now.