Hydrometeorological Discussion
Issued by NWS West Gulf RFC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7
000
AGUS74 KFWR 241613
HMDFWR
HYDROMETEOROLOGICAL DISCUSSION
NATIONAL WEATHER SERVICE...WEST GULF RFC...FORT WORTH TX
1113 AM CDT SAT SEP 24 2016

               VALID SEPTEMBER 24 THROUGH SEPTEMBER 29

...WIDESPREAD RAIN WITH LOCALLY HEAVY DOWNPOURS FORECAST THIS WEEKEND
INTO EARLY NEXT WEEK...

                  ...METEOROLOGICAL DISCUSSION...

Widespread convective precipitation can be expected over the next
few days, with a focus on western Texas. A potent upper level low
pressure system centered over Wyoming has resulted in moist
southwesterly flow in the upper atmosphere over western Texas. A cold
front has stalled along the western reaches of the Texas Panhandle.
As of late this Saturday morning, there is not much precipitation in
the area, but convective storms can be expected to develop by this
evening in western Texas as another upper level low pressure system
develops over southeastern Arizona. Locally heavy rainfall can be
expected overnight.

The new upper level system is forecast to drift southward into
northwestern Mexico on Sunday, and the cold front will begin
progressing southeastward through Texas. As the cold front
advances across Texas later Sunday into Monday, the rainfall will
increase in both coverage and intensity, but with the focus for heavy
rainfall remaining in the western half of the state. Widespread rain
in excess of two inches is forecast for most of western Texas from
tonight through early Tuesday. Locally higher amounts should be
expected, with isolated storm total amounts as high as 8 inches
currently forecast.

The cold front is forecast to exit the region by mid-week with a
return of drier weather combined with noticeably cooler
temperatures. However, continued availability of tropical moisture
will produce the potential for showers and thunderstorms in
northwestern Mexico, potentially affecting the Rio Conchos and
the Rio Grande above the Big Bend.

                    ...PRECIPITATION FORECAST...
For Today into Sunday morning, Mean Areal Precipitation (MAP)
amounts of 1 to 2 inches are forecast for portions of southwestern
Texas from the Big Bend to Amistad Reservoir and into the western
Hill Country. MAP amounts of 1 to 2 inches are also forecast for
portions of northwestern Texas near the Red River. MAP amounts of
0.25 to 1 inch are expected for most of the rest of western Texas and
for portions of the Texas coast.

For Sunday into Monday morning, MAP amounts of 2 to 5 inches are
forecast for the Permian Basin and western Hill Country of Texas.
MAP amounts of 0.25 to 1 inch are forecast for portions of the Texas
coast.

For Monday into Tuesday morning, MAP amounts of 1 to 2 inches are
forecast along a large stretch of the Rio Grande from Big Bend to
Falcon Lake. MAP amounts of 0.25 to 1 inch are forecast for most of
the rest of southern and western Texas.

For Tuesday into Thursday morning, MAP amounts of 0.25 to 1 inch are
forecast for the lower Rio Grande Valley and for portions of the
Texas coast.

Because of the widespread rain over the past few weeks over parts
of New Mexico and Texas, drought conditions remain favorable. The
U.S. Drought Monitor categorizes Texas as 4.5% abnormally dry, with
almost 1% in severe drought. New Mexico remains unchanged this
week with 47% of the state abnormally dry and 4% in the moderate
drought category.

                     ...HYDROLOGIC DISCUSSION...
...WGRFC Basins...
Soils remain relatively wet over the eastern two-thirds of the region.
Further out west, the soils continue dry and likely enough to handle
most of the upcoming rain expected later this weekend into  early next
week.  However, the rainfall amounts expected could generate minor or
greater flooding in localized headwater areas within the Texas Hill
Country.
Additionally, reservoirs in Mexico within the Rio Conchos drainage
along with reservoirs within smaller Mexico watersheds that directly
drain into the mainstem between Amistad and Falcon Reservoirs, are near
conservation and may begin regulation. This would affect Rio Grande
flows from Presidio downstream through Laredo with the onset of any
heavy, widespread rainfall within those areas of Mexico.


              ...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/reservoirs/statewide

PHILPOTT


$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.