000 AGUS74 KFWR 261632 HMDFWR HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE...WEST GULF RFC...FORT WORTH TX 1031 AM CST THU NOV 26 2009 VALID NOVEMBER 26 THROUGH DECEMBER 1 ...METEOROLOGICAL DISCUSSION... A low pressure system has moved through the midwest pushing a weak secondary cold front through the cooler air through Texas. However there was little moisture to produce any rainfall and none is expected for today into Friday. A ridge of high pressure has begun to move into the WGRFC area and will dominate the weather pattern until late Saturday. This ridge will continue to keep significant precipitation out of most of the WGRFC area through midday Saturday. During the day Friday a weak upper air disturbance will form over southwest Texas and could produce some light precipitation over the Rio Grande basin at that time. Then this disturbance will move across southern Texas Saturday producing only light, if any, precipitation. A more organized storm system is forecast to develop over southern California by Saturday night. This storm may produce some light precipitation over portions of New Mexico and Colorado Saturday night into Sunday morning. This storm will progress slowly eastward and will produce precipitation across the entire WGRFC region on Sunday into Monday morning. The rain will be concentrated over northern Texas and eastern New Mexico where the atmospheric moisture will be deepest. The rain should continue its motion southeast on Monday with increasing rainfall amounts expected as the front interacts with moisture from the Gulf. By Tuesday the front should have pushed through most of Texas with some lingering precipitation forecast for the eastern coastal region. ...PRECIPITATION FORECAST... For Today into Friday morning, no significant Mean Areal Precipitation (MAP) amounts are forecast for the WGRFC area. For Friday into Saturday morning, no significant MAP amounts are forecast for the WGRFC area. Some light MAP is forecasted for southwest Texas and northeast Mexico region during this period. For Saturday into Sunday morning, light MAP amounts with a maximum of 0.25 of an inch are forecasted for parts of northern New Mexico and southern Colorado in the WGRFC area. All of New Mexico can expect some light precipitation throughout the day. For Sunday into Tuesday morning, MAP amounts are forecasted for the entire WGRFC domain, with the heaviest rainfall expected for the far southeast coastal region of Texas. The upper Rio Grande basin is forecasted for 0.25 inches increasing for the lower Rio Grande to a forecast of 0.50 inches of MAP. The 0.50 inch forecast extends up through the Dallas area into northwest Texas, with increasing rainfall expected as you head southeast to a peak MAP level of 3.00 inches over the southeast coast of Texas and far western coast of Louisiana. The rainfall amounts for this forecast period may generate minor amounts of runoff into the rivers over east and southeast Texas and western Louisiana. However, runoff which would cause significant flooding is not expected in the WGRFC area. ...HYDROLOGIC DISCUSSION... ...Guadalupe Basin... ...Moderate Flooding... The Guadalupe River at Victoria (VICT2) will return within banks this morning. The Guadalupe River near Bloomington (DUPT2) has crested and will fall below moderate flood level this afternoon. The river will continue to recede to near flood stage over the weekend. ...Sabine Basin... ...Minor Flooding... Minor flooding will persist throughout the forecast period at the Sabine River near Deweyville (DWYT2), primarily due to controlled release from Toledo Bend. Moderate rainfall is expected over the basin at the end of the period, but only isolated out of bank to minor flooding is expected to result. ...Remainder of WGRFC Basins... All other rivers in the WGRFC area are at or near base flow. No significant rises are expected during the next few days, with only moderate precipitation forecast for the period. ...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://www.weather.gov/rivers_tab.php The Flood Potential Outlook can be viewed on our webpage at: http://www.srh.noaa.gov/?n=wgrfcfop National Precipitation Analysis: http://www.srh.noaa.gov/rfcshare/precip_analysis_new.php The forecast rainfall amounts (QPF) can be viewed on our webpage at: http://www.srh.noaa.gov/?n=wgrfcqpfpage The US Drought Assessment: http://www.cpc.noaa.gov/products/expert_assessment/drought_assessment.shtml GIARDINO $$