Hydrometeorological Discussion
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AGUS74 KFWR 291605
HMDFWR
HYDROMETEOROLOGICAL DISCUSSION
NATIONAL WEATHER SERVICE...WEST GULF RFC...FORT WORTH TX
1105 AM CDT FRI MAY 29 2015

                     VALID MAY 29 THROUGH JUNE 3

...ADDITIONAL SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH
SUNDAY...

                  ...METEOROLOGICAL DISCUSSION...
Over the last 24 hours, very heavy rainfall occurred over a
large portion of the WGRFC area, causing lots of flash flooding
and additional river rises once again. Another complex of
thunderstorms developed over the Texas Panhandle yesterday
afternoon, and thereafter moved over North Texas. As this system
moved over North Texas last night, very heavy rainfall begin
across the DFW Metroplex and continued through this morning. As a
result of this long duration of rainfall, lot of rivers responded
rather quickly across the Trinity and Brazos River systems.
Overall, rainfall amounts of 6-7 inches were reported within
the DFW Metroplex, and on average 1-2 inches fell across
Northwest and Central Texas.

Currently, the complex of storms has dissipated and moved off
towards the east. Some scattered showers and thunderstorms are
expected to continue on and off for the remainder of the day,
however no widespread rainfall is expected until late
tonight/early tomorrow.

By late tonight through tomorrow morning...a cold front is
forecast to approach the WGRFC area from the northwest. As it
moves across Texas tonight, another 0.50 to 1.00 inch is
expected across North and Northwest Texas. Thereafter,
rainfall is expected to spread across Central and East Texas...
as the front continues moving southward.

The latest forecast models are still indicating a little relief
insight for next week. Some rainfall is expected for the next
several days, however widespread rainfall is not expected after
Sunday. Although significant rainfall is not forecast after
Sunday, moderate and Major flooding is expected to continue
for the next couple of weeks.

                    ...PRECIPITATION FORECAST...
For Today into Saturday morning, Mean Areal Precipitation (MAP)
amounts of up to 1.00 inch are forecast for portions of the
Texas Panhandle, North Texas and East Texas.

For Saturday into Sunday morning, MAP amounts of 0.25 to 0.50
inch are forecast for most of the WGRFC area...excluding
West Texas, Colorado and New Mexico.

For Sunday into Monday morning, MAP amounts of 0.25 to 0.50 inch
are forecast for the upper Texas coast. Lesser amounts are
forecast for East Texas.

For Monday into Wednesday morning, no significant MAP amounts
are forecast for the WGRFC area.

Drought conditions continue to improve across most of the WGRFC
area. Recent precipitation events have brought drought relief
to many parts of Texas.  In Texas, only about 15% of the state
is experiencing moderate or worse drought, and extreme to
exceptional drought conditions are no longer being observed.
In New Mexico, a little over a third of the state is experiencing
moderate or worse drought (37%), and they also are free from extreme
or exceptional drought conditions. Many of the lakes in Texas
have levels which have risen due to recent rainfall, and some lakes
are full and are releasing water. The rainfall expected over the
next five days over especially the northern half of Texas will be
heavy enough to produce significant runoff, and minor runoff is
expected over the remainder of Texas. Elsewhere over the WGRFC
area no significant runoff is anticipated.

                     ...HYDROLOGIC DISCUSSION...
...Guadalupe Basin...
...Major Flooding...
The flood wave that was generated from the flash flood
emergency earlier this week on the Blanco River had finally
passed Cuero (CUET2) reaching just inches below major flood level.
The next stop is Victoria (VICT2) which is slowly approaching its
major flood level, but should crest within an inch either side of
major flood level any time now. Downstream at Bloomington (DUPT2),
the gage is still rising and should break over the major flood
level over the weekend. Small waves have been generated upstream
on some of the tributaries, but none will match the levels of the
current event.

...Nueces Basin...
...Major Flooding...
Asherton has finally receded within banks but the water continues
to move downstream.  Cotulla has crested from local and routed
rainfall overnight, but isn`t expected to start receding for another
day or so. The water has arrived at Tilden and continues to rise at
dangerous levels.  The model is having difficulty with the routing
of this level of water, but it appears to be close to cresting
initially later tonight, before a secondary crest later in the
period. Water from the Frio should arrive in the next few days at
Three Rivers driving the forecast into moderate flood. The releases
from Lake Corpus increased slightly, causing Bluntzer to reach
major and Calallen forecasted to rise back into moderate flood.

...San Jacinto Basin...
...Major Flooding...
The West Fork of the San Jacinto river near
Porter (PTET2) and at Humble (HMMT2) are currently in major
flood category. Widespread minor flooding and above normal flow
levels continue across the San Jacinto River basin. With last
nights rainfall being lighter than recent rains, the rivers will
have time to recover some before the next event over ther weekend.

...Trinity Basin...
...Major Flooding...
Continued heavy rainfall across the entire Trinity River drainage
has caused widespread bankfull, minor, and moderate flood flow
conditions. Rainfall in the past 24 hours across the upper Trinity
thru Rosser (RSRT2) has caused quick rises in the DFW metroplex
along with water supply reservoirs and flood-control reservoirs
within surcharge passing inflows.  These combined flows, along with
local watershed runoff, have generated major flood levels at Dallas
(DALT2) and is expected to crest around 43ft overnight; major
flooding will continue downstream at Rosser (RSRT2) Saturday
overnight.  The Trinity River at Trinidad (TDDT2), near Long Lake
(LOLT2), and at Liberty (LBYT2) locations continue above major
flood levels and expected to rise further with additional flows
upstream.

The Padera Lake within the Joe Pool Lake drainage being monitored
is expected to fail, and will become inflows to Joe Pool. Flood
control reservoirs within the system with available flood storage
continues to store flood waters to minimize downstream flood
conditions.

...Colorado Basin...
...Major Flooding...
Another wave of water has developed on the Llano River from the
heavy rains overnight.  Upstream, the river is not above flood
criteria (MLRT2), but has generated enough flow to cause a
secondary crest downstream. The main gage at Llano (LLAT2) has
already crested just above the moderate flood level and will fall
rapidly, but should increase again when the upstream water arrives.
No flooding is expected with the secondary rise. This water is
heading for the Highland Lakes system and should not cause any
additional flooding. The mainstem of the Colorado River below Austin
continues to move the latest major flood event downstream.  The peak
water has passed Columbus (CBST2) and arrived in Garwood (GWCT2).
The Colorado River at Wharton (WHAT2) is expected to continue to
rise for another 24 hours but is expected to just go over major
flood level. Elevated flows below flood stage will continue
downstream.

...Brazos Basin...
...Major Flooding...
Heavy, localized rain (2 to 4 inches) fell, again between Possum
Kingdom Lake and Lake Whitney.  This is causing additional rises
on the Brazos River for Palo Pinto, Dennis, and the Horseshoe Bend
area. Major flooding is forecast to occur on the Brazos River at
Richmond (RMOT2).  The river at this location is forecast to crest
around 50 feet Saturday / Sunday.  At a river level of 50.2, the
Fort Bend Levee Improvement District enters into critical flood
fighting operations.

...Neches Basin...
...Moderate Flooding...
The Neches River system remains in elevated flow levels with
several locations currently in flood.  The Neches River near Alto
(ATOT2) is at moderate levels.  Nearly every forecast point within
the Neches River system is above flood stage or forecast to rise
above flood stage. Lakes in the region are all full and are passing
their inflows unless designed for flood control. B.A. Steinhagen
Lake has stabilized with their current releases, but additional
rainfall could require additional increases this weekend. The
coastal sites (SOLT2), (BEAT2), (KOUT2) should remain in minor flood
stages. Sam Rayburn remains below its surcharge area, but  is still
rising.

...Sabine Basin...
...Moderate Flooding...
With the bulk of the rainfall missing the upper Sabine, the rivers
continue to push the water towards Toledo Bend.  It appears that
Tawakani has reached its maximum release over the spillway, as
water at Mineola appears to have crested and dropped below
moderate. Hawkins remains on the rise as water works its way
downstream and Gladewater is forecasted to reach moderate flood
from both local and routed water. Downstream of Toledo Bend, both
Bon Weir and Deweyville are crested or receding from lower flows
out of the reservoir.

...San Antonio Basin...
...Moderate Flooding...
The flood wave generated during the flash flood on Cibelo Creek
has finally reached Goliad (GLIT2) and should crest several feet
into the moderate flood level,  Minor secondary rises are likely
with small events upstream.

...San Bernard Basin...
...Moderate Flooding...
Moderate flooding is expected across the San Bernard Basin.
East Bernard (EBBT2) and Boling (BOLT2) will crest this weekend.

...Lavaca-Navidad Basin...
...Minor Flooding...
Minor flooding will recede. Higher criteria, non-flood conditions,
are expecte at Ganado (GNDT2) and Tres Palacios Midfield (MTPT2).
Morales (MRAT2) and Strane Park (LSNT2) will slowly recede.

...Rio Grande Basin...
...Higher Flow Non-Flood Forecasts...
Releases out of Marte Gomez Reservoir in Mexico are driving a
rise on the Rio Grande near San Benito and Ramirez (SBNT2).
This rise will continue downstream to Brownsville and Matamoros.

...Remainder of WGRFC Basins...
Currently, most rivers are have ongoing flooding conditions and
remain very sensitive to further rainfall. Soil conditions remain
very saturated and any further rainfall will only exacerbate the
ongoing flooding.


              ...SUPPLEMENTARY GRAPHICAL INFORMATION...
The following URLs (all lower case) provide additional graphical
information on current and forecast hydrologic conditions, past and
future precipitation, and drought and climate forecasts.  This
information is provided by a variety of National Weather Service,
NOAA, and private sector entities.

For specific information on river conditions, refer to the AHPS
pages from the local NWS offices at:
http://water.weather.gov/ahps/

The Flood Potential Outlook can be viewed on our webpage at:
http://www.srh.noaa.gov/wgrfc/?n=wgrfcfop

The West Gulf River Forecast Center is now on Facebook:
http://www.facebook.com/US.NationalWeatherService.WGRFC.gov

National Precipitation Analysis:
http://water.weather.gov/precip/

The forecast rainfall amounts (QPF) can be viewed on our webpage at:
http://www.srh.noaa.gov/wgrfc/?n=wgrfcqpfpage

The US Drought Assessment:
http://www.cpc.ncep.noaa.gov/products/Drought

The latest on Reservoir Information for Texas:
http://www.waterdatafortexas.org

MCCANTS


$$





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