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FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
122 AM CST THU MAR 10 2016

TXC015-089-157-239-321-481-101015-
/O.NEW.KHGX.FA.Y.0011.160310T0722Z-160310T1015Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WHARTON TX-COLORADO TX-MATAGORDA TX-AUSTIN TX-FORT BEND TX-
JACKSON TX-
122 AM CST THU MAR 10 2016

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLOOD ADVISORY FOR...
WHARTON COUNTY IN SOUTHEASTERN TEXAS...
SOUTHEASTERN COLORADO COUNTY IN SOUTHEASTERN TEXAS...
MATAGORDA COUNTY IN SOUTHEASTERN TEXAS...
SOUTHEASTERN AUSTIN COUNTY IN SOUTHEASTERN TEXAS...
WEST CENTRAL FORT BEND COUNTY IN SOUTHEASTERN TEXAS...
EASTERN JACKSON COUNTY IN SOUTH CENTRAL TEXAS...

* UNTIL 415 AM CST

* AT 120 AM CST..DOPPLER RADAR INDICATED CLUSTERS OF STRONG STORMS
PRODUCING RAINFALL RATES UP TO 2 INCHES PER HOUR AT TIMES. ONE
INCH OF RAIN HAS ALREADY FALLEN ACROSS PARTS OF THE AREA AND
ADDITIONS HEAVY DOWNPOURS WILL CAUSE MINOR FLOODING IN THE
ADVISORY AREA.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
MATAGORDA...BAY CITY...EL CAMPO...WHARTON...PALACIOS...SOUTH TEXAS
NUCLEAR PLANT...EAST BERNARD...GANADO...WALLIS...LA WARD...MARKHAM...
PIERCE...BLESSING...HUNGERFORD...WADSWORTH...EGYPT...DANEVANG...LOUISE...
GARWOOD AND MIDFIELD.

Good morning all! Keeping an eye on the radar with you overnight. Noticing rainfall rates in the strongest cells at about 1.2" per hour. Not enough to cause major flooding yet, but concerning. Bayous responding but most well within banks for now. Going to be plenty of high water spots and ponding on roadways by morning. Cheers all!

MESOSCALE PRECIPITATION DISCUSSION 0066
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
202 AM EST THU MAR 10 2016

AREAS AFFECTED...SE TEXAS...W LOUISIANA

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 100702Z - 101232Z

SUMMARY...SHORTWAVE/SURFACE WAVE PROVIDING LIFT/INSTABILITY AND
MST TRANSPORT TO REINVIGORATE DEEP CONVECTION ACROSS AREA
CURRENTLY EXPERIENCING FLASH FLOODING FURTHER COMPOUNDING AN
ALREADY DANGEROUS AND LIFE THREATENING SITUATION.

DISCUSSION...A VIGOUROUS SHORTWAVE AND LEADING NOSE OF JET STREAK
HAS ADVANCED TO THE CENTRAL PORTION OF THE WESTERN GULF OF MEXICO.
RADAR AND SURFACE ANALYSIS INDICATES SURFACE INFLECTION WITH
BULGED/BOWED COLD FRONT ADVANCING NORTHWARD. SURFACE PRESSURE
FALLS AND ISALLOBARIC WIND ENHANCEMENT WILL INCREASE LOW LEVEL
SOUTHERLY JET IN EXCESS OF 60KTS AT 850MB FOCUSED TOWARD THE
GALVESTON BAY AND EASTWARD BY 9-10Z...COINCIDENT WITH TPWS OF 2.0"
AND CAPES FORECAST NEAR 2500-3000 J/KG PER 00Z ARW/NMMB AND NSSL
WRF SHOULD SUPPORT STRENGTHENING CONVECTION NEAR AND EAST OF THE
FRONTAL ZONE CURRENTLY ORIENTED SW TO NE ACROSS SE TX INTO CENTRAL
LA WITH RATES OF 2-3"/HR LIKELY WITHIN A GENERAL N-S TRAINING
PROFILE WITH REPEAT DEVELOPMENT ALONG THE FRONTAL ZONE THAT WILL
SLOWLY ADVANCE FROM WEST TO EAST BY 12Z INTO W LA...WITH THE
POTENTIAL FOR AN ADDITIONAL 3-6" NEAR THE FRONT. GIVEN STRENGTH
OF LOW LEVEL FLOW/MST FLUX... CONVECTION WILL ISENTROPICALLY LIFT
INTO EAST CENTRAL TX...N LA AS THE SHORTWAVE ADVANCES
NORTHWARD...ALONG WITH PERIPHERAL ASCENT PROVIDED BY RIGHT
ENTRANCE DYNAMICS FROM 130-140 KT ANTICYCLONICALLY CURVED POLAR
JET OVER THE MO RIVER VALLEY...EVEN MODERATE SHIELD PRECIPITATION
WILL BE HIGHLY EFFICIENT OVER AREAS THAT HAVE RECEIVED OVER 12"
PLUS IN THE LAST TWO DAYS NEAR/ALONG THE I-20
CORRIDOR...COMPOUNDING ONGOING FLOODING IN THIS VICINITY AS WELL.

FURTHER WEST ACROSS SE TX...THE ADVANCING WAVE WILL HAVE A NICE
TROWAL WITH SOME EMBEDDED CONVECTIVE ELEMENTS WITHIN THEM...THOUGH
NOT FULLY ROOTED NEAR THE SURFACE...THIS WAVE WILL PROVIDE STRONG
ASCENT AT THE LEFT EXIT OF THE APPROACHING MID-LEVEL JET
STREAK/DRYING SEEN ACROSS THE WESTERN GULF. GIVEN SOME STEEPER
LAPSE RATES...THESE STRONGER THE CELLS WILL SUPPORT RATES UP TO
1.5-2"/HR BUT SHOULD BE QUICKER MOVING...AND POSE ONLY SHORT TERM
FF CONCERNS IF CROSSING LOWERED AREAS WITH LOWERED FFG VALUES DUE
TO PRIOR ROUNDS OF CONVECTION OVER THE LAST DAY OR SO. THE
WESTERN CELLS ALONG THIS AXIS SHOULD SLOW AND SHEAR MOISTURE BACK
TOWARD THE UPPER LOW WITHIN THE DEFORMATION ZONE WILL PROVIDE SOME
MODERATE RAINFALL AT TIMES ACROSS CENTRAL TX THOUGH NOT LIKELY
ENOUGH TO SUPPORT FLOODING CONCERNS ATTM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
218 AM CST THU MAR 10 2016

TXZ210>212-226-227-236-237-100900-
MATAGORDA TX-AUSTIN TX-BRAZORIA TX-WALLER TX-COLORADO TX-WHARTON TX-
FORT BEND TX-
218 AM CST THU MAR 10 2016

...SPECIAL WEATHER STATEMENT...

AT 218 AM CST...DOPPLER RADAR WAS TRACKING A CLUSTER OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 6 MILES SOUTHWEST OF EAST
BERNARD TO 7 MILES NORTHWEST OF WEST COLUMBIA...AND MOVING NORTHEAST
AT 30 MPH.

WINDS IN EXCESS OF 30 MPH WILL BE POSSIBLE WITH THESE STORMS.

LOCATIONS IMPACTED INCLUDE...
ROSENBERG...WESTERN ANGLETON...BAY CITY...WHARTON...WEST COLUMBIA...
SWEENY...EAGLE LAKE...NEEDVILLE...EAST BERNARD...WALLIS...FULSHEAR...
HOLIDAY LAKES...PLEAK...SIMONTON...FAIRCHILDS...BAILEY`S PRAIRIE...
BEASLEY...KENDLETON...ORCHARD AND BRAZOS BEND STATE PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THESE STORMS...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
250 AM CST THU MAR 10 2016

TXC015-039-157-201-339-473-101045-
/O.NEW.KHGX.FA.Y.0012.160310T0850Z-160310T1045Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
HARRIS TX-WALLER TX-MONTGOMERY TX-BRAZORIA TX-AUSTIN TX-FORT BEND TX-
250 AM CST THU MAR 10 2016

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* URBAN AND SMALL STREAM FLOOD ADVISORY FOR...
SOUTHWESTERN HARRIS COUNTY IN SOUTHEASTERN TEXAS...
SOUTHERN WALLER COUNTY IN SOUTHEASTERN TEXAS...
SOUTHWESTERN MONTGOMERY COUNTY IN SOUTHEASTERN TEXAS...
NORTHWESTERN BRAZORIA COUNTY IN SOUTHEASTERN TEXAS...
EAST CENTRAL AUSTIN COUNTY IN SOUTHEASTERN TEXAS...
FORT BEND COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 445 AM CST

* AT 246 AM CST...DOPPLER RADAR INDICATED CLUSTERS OF STRONG STORMS
PRODUCING RAINFALL RATES UP TO 2 INCHES PER HOUR AT TIMES. 2 TO 4
INCHES OF RAIN HAVE ALREADY FALLEN OVERNIGHT ACROSS PARTS OF THE
AREA AND ADDITIONS HEAVY DOWNPOURS WILL CAUSE MINOR FLOODING IN
THE ADVISORY AREA.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
NORTHWESTERN PEARLAND...SUGAR LAND...MISSOURI CITY...ROSENBERG...
STAFFORD...BELLAIRE...WEST UNIVERSITY PLACE...KATY...RICHMOND...GALENA
PARK...TOMBALL...JACINTO CITY...JERSEY VILLAGE...BROOKSHIRE...HUNTERS
CREEK VILLAGE...BUNKER HILL VILLAGE...PINEY POINT VILLAGE...PINEHURST...
ASTRODOME AREA AND SPRING VALLEY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE PONDING OF WATER IN
URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES AS WELL AS OTHER POOR
DRAINAGE AREAS AND LOW LYING SPOTS. DO NOT ATTEMPT TO TRAVEL ACROSS
FLOODED ROADS. FIND ALTERNATE ROUTES.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST.

Hopefully we can get this stubborn Low to move on and give Texas and especially Louisiana a break!!!





EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
355 AM EST THU MAR 10 2016


...LOWER MISSISSIPPI VALLEY / WESTERN GULF COAST UP THROUGH
WESTERN TN/KY...

A BROAD MODERATE RISK OF EXCESSIVE RAINFALL IS FORECAST FROM
BEAUMONT TEXAS ACROSS MUCH OF LOUISIANA AND INTO PORTIONS OF
WESTERN MISSISSIPPI AND TENNESSEE...AND EASTERN ARKANSAS. A SLIGHT
RISK SURROUNDS THE MODERATE RISK AND EXTENDS FARTHER NORTH TO
LOUISVILLE KENTUCKY. A SYNOPTICALLY EVIDENT FLASH FLOOD EVENT HAD
PRODUCED SEVERE IMPACTS ACROSS PORTIONS OF THIS REGION ON
WEDNESDAY. ADDITIONAL WIDESPREAD RAIN AND SOME VERY HEAVY RAIN IS
FORECAST TODAY...AND ALTHOUGH THE AXIS OF GREATEST NEW RAINFALL
AMOUNTS WILL BE SLIGHTLY FARTHER EAST...THERE WILL BE SOME OVERLAP
OF MODERATE RAINS BACK INTO AREAS THAT WERE HIT HARD YESTERDAY.

NO SINGLE MODEL QPF WAS HANDLING ALL OF THE DETAILS PARTICULARLY
WELL...ALTHOUGH ON THE LARGE SCALE THERE WAS GOOD AGREEMENT AMONG
THE GFS/ECMWF/UKMET/GEM REGIONAL. THERE WAS A SOMEWHAT SURPRISING
AMOUNT OF SPREAD WITH RESPECT TO DETAILS AMONG THE HI-RES MODELS.
WE FAVORED THE GEM REGIONAL...ESPECIALLY THE 18Z RUN...AS WELL AS
THE 00Z NSSL
WRF. THE 00Z WRF-ARW ALSO HINTED AT THE MORE EXTREME NATURE OF THE
RAIN RATES OVER LOUISIANA...BUT MAY ACTUALLY BE OVERDONE GIVEN
MORE FORWARD PROPAGATION TODAY.

THE BROAD CORRIDOR OF 1.50 TO NEAR 2.00 INCH PW FEEDING OFF
MOISTURE FROM THE CARIBBEAN AND TROPICAL PACIFIC WAS VERY
ANOMALOUS...AS GULF COAST ANOMALIES RARELY PUSH HIGHER THAN THE
2.5 TO 3 STANDARD DEVIATIONS NOW BEING OBSERVED BASED ON THE
ALREADY HUMID CLIMATE IN THAT REGION. THIS GIVES US REASON TO
CONTINUE PUSHING FORECAST AMOUNTS TOWARD THE HIGH SIDE OF THE
MODEL GUIDANCE...DESPITE THE FACT THAT EVENTS ON THURSDAY SHOULD
NOT BE QUITE SO FOCUSED AS THEY WERE WHEN 10 TO 16 INCHES OF RAIN
FELL YESTERDAY.

THIS MORNING A CONFLUENT LOW LEVEL FLOW REGIME WILL PERSIST FROM
NORTHWEST MISSISSIPPI THROUGH CENTRAL KENTUCKY...IN THE ENTRANCE
REGION OF A NORTHERN STREAM JET STREAK. THIS AREA WAS DOWNWIND OF
THE INSTABILITY AXIS NEAR THE GULF COAST...WITH SOME DEEP
CONVECTION NOTED OVER NORTHWEST MS AT 06Z...BUT WITH LITTLE
CONVECTIVE ENHANCEMENT TO THE PRECIPITATION FARTHER NORTH. THE
FORCING SUPPORTING THIS NARROW QPF AXIS SHOULD PERSIST THROUGH MID
AFTERNOON BEFORE TENDING TO RELAX OVER THE TENNESSEE VALLEY AND
ADJACENT REGIONS AS A NORTHERN STREAM WAVE MAKES PROGRESS TOWARD
THE UPPER OHIO VALLEY AND NEW ENGLAND...SPURRING AN INCREASE OF
PRECIPITATION IN THAT CORRIDOR.

BACK TOWARD THE GULF COAST...SOME DEGREE OF MID LEVEL DRY AIR WAS
WRAPPING AROUND THE DEEP LOW CENTER IN MEXICO...YIELDING
THUNDERSTORMS WITH A LITTLE MORE OUTFLOW AND FORWARD PROPAGATION
ACROSS SOUTHEAST TEXAS THIS MORNING. SUCH BEHAVIOR IS GENERALLY
EXPECTED TODAY...ESPECIALLY AS LOW LEVEL WIND SPEEDS ARE FORECAST
TO DROP OFF ONCE THE NORTHERN STREAM WAVE AND ASSOCIATED JET
STREAK START TO MOVE ON...AND RELAX THE SYNOPTIC GRADIENTS A BIT.
THE DIP IN LOW LEVEL WINDS WILL RESULT IN LESS RESISTANCE TO
EASTWARD MOVEMENT BY THIS AFTERNOON/EVENING...BUT PRECIPITATION
SHOULD NONETHELESS BE WIDESPREAD AND VERY EFFICIENT AT DUMPING
HEAVY AMOUNTS GIVEN THE COMBINATION OF HIGH PW AND MODERATE CAPE
OVER PARTS OF SOUTHERN LOUISIANA AND MISSISSIPPI. THE GREATEST
OVERLAP OF SLIGHT HEIGHT FALLS / Q-VECTOR CONVERGENCE WITH THE
AXIS OF DEEPEST MOISTURE SHOULD OCCUR DURING THE MORNING HOURS
OVER THE UPPER TX COAST AND SOUTHWEST LOUISIANA...YIELDING
EXPANSION OF ANOTHER MCS...AND SENDING IT ON A SLOW EASTWARD
MARCH. STRATIFORM PRECIPITATION BACK TO THE NORTH AND WEST MAY
DELIVER ANOTHER 1-2 INCHES OF RAIN ON AVERAGE TO NORTHWEST
LOUISIANA...WHILE THE STRONGER STORMS AT THE LEADING EDGE WILL
LIKELY PRODUCE RAIN RATES 2.5 INCHES PER HOUR.

THE FORECAST TODAY WAS NOT AS CLEAR CUT...NOR AS FOCUSED...TO
SUPPORT A HIGH RISK AREA...AND THE HEAVIEST RAIN WILL FALL IN
AREAS OF HIGHER FLASH FLOOD GUIDANCE. SO WE HAVE A BROAD MODERATE
RISK INSTEAD.

Thanks djjordan and David for keeping the folks updated. We've had torrential rains with pea sized hail for about the past hour here in NW Harris County. Really concerned for our neighbors in E Texas and Louisiana. I know that water has entered homes in the Tyler and Shreveport areas. Stay safe this morning during the commute.

Additional showers and thunderstorms across a large portion of TX today however the heavy rain threat for SE TX has diminished enough that the Houston-Galveston NWS will allow the Flash Flood Watch to expire at 6AM. Additional heavy rains may occur to the E and NE of the Houston-Galveston areas this afternoon. The upper level low will begin to drift N into TX and shear out over the eastern half of TX Saturday. Some areas in NW LA have seen up to 18" of rain while some areas of Harris County have seen up to 7" of rain. If you encounter high water this morning during the commute do not drive through it. Another thanks to djjordan and David for keeping the weather information flowing during the night.

A good slug of heavy rain just pushed onto the coast on the West side of Houston moving north quickly. Looks like that will get to my neck of the woods after a bit. 6 1/2" total so far at my house. No more please.

I had measured 3.32" as of 5am in SW Houston, but the area is being hit by a heavy storm now.

Rain increasing again with thunder and lightning here in the woodlands

Mark Sudduth
‏@hurricanetrack

S Mayde Creek yesterday vs just now. @JeffLindner1 @hcfcd

https://twitter.com/hurricanetrack/stat ... 6823359492

live flood cams http://hurricanetrack.com/flood/

https://twitter.com/hcfcd/with_replies

* http://www.harriscountyfws.org/

* Adding: don't forget you can get "channel status" by changing the default of "rainfall" under "Map View Options" in upper left corner. You can also select "ALL" under "Gage Selection" to view all participating, outside Harris County

don't let your guard down, some areas still have rising water

https://twitter.com/HCOHSEM/with_replies

https://twitter.com/JeffLindner1/with_replies

Lake Conroe

http://www.lakeconroewebcams.com/

This monitor has elevation, rainfall and weather tabs
http://www.harriscountyfws.org/GageDetail/Index/2500

Just emptied 6.38 inches of rain from the rain gauge for the past 48 hours. Update from Jeff regarding Toledo Bend and the Sabine River:

Tremendous rainfall of 10-15 inches over the last 36 hours has resulted in a very large rise on Toledo Bend on the Sabine River.

A massive release of 207,000 cfs is currently underway at the dam with 9 flood gates opened 22 ft. In the last 2 hours the gates have been raised 5 ft to help stabilize the massive rise in progress on the lake.

Possible record flooding downstream along the Sabine River below Toledo Bend at Burkeville, TX with major to record flooding at Bon Weir and Deweyville.

Sabine River at a glance http://www.texasriverdata.com/sabine.html









Texas at a glance http://waterdata.usgs.gov/tx/nwis/rt

I had 6.4 inches at my house in Magnolia.

Update from Jeff regarding Toledo Bend/Sabine River:

This is a life threating flood situation for the Sabine River below Toledo Bend Reservoir.

Follow instructions from law enforcement and emergency management officials immediately.

Record release continues from Toledo Bend. Forecast flood wave to reach Burkeville, TX and surpass previous flood of record by 5.0 ft.

Potential record flooding at Deweyville, TX surpassing the previous record from 1884

Jeff Update:

All-time record flood imminent on the lower Sabine River.

Mandatory evacuation order in effect for both the TX and LA side of the river downstream of Toledo Bend. This is a life threatening situation…follow emergency advice immediately.

Lake has reached 3rd highest pool (173.76ft) before massive release began at 600am. Latest data from the dam indicates the lake pool is rising again after a 1.5 ft fall as a result of the large releases this morning. The lake pool is not stabilized and additional gate increases are imminent to attempt to slow the pool rise and reduce pressure against the dam.