Flash Flood Warning 52, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
444 AM CDT THU JUN 2 2016

.DISCUSSION...
What can be said that hasn't already been communicated over these
past few days? We are entering into this latest high severe
weather event that will again likely produce another 2 to 4
inches of areawide rainfall...with localized amounts in excess of
8 inches...over the next 48 to 72 hours. The upper low over the
Trans Pecos region has transitioned to a broad open wave trough
whose positive tilted axis lays over the western half of the
state. A vigorous shortwave disturbance ejecting eastward from
this trough is initializing flood-producing convection over San
Antonio's forecast area this morning...and this wave will be
rotating across our CWA through the daylight hours. This most
likely scenario will be for this shortwave to trigger periods of
moderate to locally heavy precipitation from near sunrise through
early evening... clusters of thunderstorms will drop an average 1
to 3 inches of precipitation with localized amounts exceeding 6
inches. This...in short...will reaggravate the regions' flooding
woes both from a sheet/flash flooding and rising... swollen river
flood threat. The real secondary threat will be wind...it will
not take as much wind to topple trees within this very saturated
soil. Thunderstorm wet downbursts on the range of 30 to 40 kts
will bring trees down...strongest winds in excess of 45 knots may
produce residential and business damage. Can't rule out a brief
weak tornado forming along any bowed segment or line break but...
with this very tropical near 2" PWAT tropical air mass...early
day offshore waterspouts may be observed within nearshore convection
moving ashore.

The warm core mid-upper low sitting sitting over the forecast area
for a good day or so will eventually shear out over the weekend
(high confidence mention). As it does...lowering coastal pressures
Friday into Saturday will aid in enhancing lower level convergence
that may focus higher rainfall further south...this all dependent
on the location of the trough axis --> sets up along near a Highway
59 corridor then high rainfall occurs over the coastal counties
while if it sets up along or near parallel to the upper Texas coastline
then the high rainfall will occur where most want it...over the
Gulf. As the surface trough stretches out/low moves northeast...a
frontal boundary will travel over the CWA and veer winds northerly
early Sunday. This will be the beginning of the end of this early
June high rainfall event. Higher rain chances will linger along
the coast and points offshore Sunday before falling to below
mentionable early Monday. Slight chance POPs will only exist along
the sea breeze boundary Monday through Wednesday as the state falls
on the far eastern edge of a eastern Pacific/Baja region upper
ridge.

Rain and overcast will maintain relatively cooler temperatures of
near 10 degrees below normal afternoon maximums...muggy upper 70
to lower 80 maximums/upper 60 to middle 70 minimums through Saturday.
Once the bulk of the inclement weather clears early next
week...subsequent work week temperature readings will warm back
up into the mean upper 80s to lower 90s through the dry out
period. 31

&&

.MARINE...
Onshore flow has come back up in advance of storm complex currently
in cntl Tx. Will re-hoist the caution flags in the Gulf waters into
the early aftn hours. Anticipate this storm complex to move
into/impact the upper Tx coastal waters between now and that time as
well with locally higher/rough waters. Expect winds/seas to weaken a
bit late in the day, but repeat scenarios can be expected into the
weekend as a series of upper level disturbances move overhead and
produce periods of unsettled weather. May see a weak frontal
boundary approach the coast later this weekend, but there is still
considerable uncertainty in regards to timing. 47

&&

.AVIATION...
Look for increasing tstm coverage this morning...persisting into the
mid/late aftn hours. Favorable upper level pattern for locally
heavy/training cells. Will probably see somewhat a break in the
precip this evening...followed by regeneration overnight. As long
the the upper low remains to our west (which it should going into
the weekend) look for disturbances rotating around it to trigger
periods of unsettled wx and storm complexes. Outside of convection,
expect mostly VFR conditions, but maybe some patchy shallow fog at
night. 47

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      79  68  81  68  81 / 100  50  60  60  70
Houston (IAH)              79  69  83  69  82 /  90  60  70  60  70
Galveston (GLS)            81  74  81  76  81 /  90  90  70  80  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch through Friday evening FOR THE FOLLOWING
     ZONES: Austin...Brazoria...Brazos...Burleson...Chambers...
     Colorado...Fort Bend...Galveston...Grimes...Harris...
     Houston...Jackson...Liberty...Madison...Matagorda...
     Montgomery...Polk...San Jacinto...Trinity...Walker...
     Waller...Washington...Wharton.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 3 PM CDT this
     afternoon FOR THE FOLLOWING ZONES: Coastal waters from
     Freeport to the Matagorda Ship Channel out 20 NM...Coastal
     waters from High Island to Freeport out 20 NM...Waters from
     Freeport to the Matagorda Ship Channel from 20 to 60 NM...
     Waters from High Island to Freeport from 20 to 60 NM.

&&

Discussion...31/47

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
715 AM CDT THU JUN 2 2016

TXZ163-164-176>179-195>200-210>214-226-227-235>238-031215-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
715 AM CDT THU JUN 2 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

AN UPPER LEVEL DISTURBANCE COMING AROUND AN APPROACHING WESTERN
UPPER LOW...COUPLED WITH DEEP MOISTURE AND FAVORABLE UPPER LEVEL
WINDS...WILL PRODUCE PERIODS OF MODERATE TO HEAVY RAIN WITHIN
PASSING THUNDERSTORMS. AREAWIDE RAINFALL TOTALS WILL AVERAGE
BETWEEN 1 AND 3 INCHES...BUT THERE WILL BE ISOLATED TOTALS THAT
EXCEED 5 TO 6 INCHES. HOURLY RAINFALL RATES OF 2 INCHES WILL
LIKELY CREATE...OR RE INTRODUCE...FLASH FLOODING. A SECONDARY
THREAT WILL BE STORM WINDS GREATER THAN 30 MPH IN GUST. WINDS OF
THIS MAGNITUDE MAY TOPPLE TREES PER THE ONGOING SATURATED NATURE
OF REGIONAL SOILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A UPPER LOW WILL MOVE OVER THE REGION FRIDAY AND THIS WILL CREATE
ENOUGH INSTABILITY WITHIN A DEEPLY MOIST ENVIRONMENT TO REGENERATE
PERIODS OF SHOWERS AND THUNDERSTORMS. RAINFALL TOTALS OF 1 TO 3
INCHES WILL BE POSSIBLE ONCE AGAIN...WITH LOCALIZED AMOUNTS OF
GREATER THAN 4 INCHES. FLOODING AND WINDS WILL AGAIN BE THE MAIN
THREAT THROUGH SATURDAY.

A POSSIBLE FRONTAL BOUNDARY SLOWLY SAGGING INTO THE AREA LATER THIS
WEEKEND MAY PROVIDE ADDITIONAL NEAR COASTAL FOCUS FOR CONTINUED DAILY
PRECIPITATION INTO EARLY MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS NEED TO BE AWARE OF SEVERE WEATHER OCCURRENCES...FROM HIGH
RAINFALL RATES LEADING TO FLOODING TO DAMAGING WIND AND POSSIBLY ISOLATED
TORNADOES TODAY THROUGH THE WEEKEND.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE Houston/Galveston TX
738 AM CDT THU JUN 02 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0716 AM     MARINE TSTM WIND PALACIOS                28.71N  96.24W
06/02/2016  M44 MPH          MATAGORDA          TX   ASOS

&&

EVENT NUMBER HGX1600205

BLOOD