HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1100 AM CDT FRI MAY 2 2008
...DROUGHT INFORMATION STATEMENT...
...STRONG LATE SEASON COLD FRONT BRINGS WELCOME RAINS TO DEEP SOUTH 
TEXAS...
...EXCEPTIONAL DROUGHT CONDITIONS PERSIST OVER ZAPATA, JIM HOGG, 
NORTHERN STARR AND WESTERN BROOKS COUNTIES...
SYNOPSIS...
A STRONG LATE SEASON COLD FRONT TREKKING THROUGH DEEP SOUTH TEXAS 
ENCOUNTERED A WARM AND HUMID AIR MASS, RESULTING IN NUMEROUS SHOWERS 
AND THUNDERSTORMS ON THE 27TH OF APRIL. THIS WAS THE FIRST 
WIDESPREAD RAINFALL THE REGION HAS RECEIVED SINCE JANUARY. RAINFALL 
TOTALS AVERAGED A QUARTER TO HALF AN IN INCH OVER ZAPATA, JIM HOGG 
AND STARR COUNTIES. THE EASTERN COUNTIES RECEIVED 1 TO 2 INCH 
TOTALS. HEAVIEST AMOUNTS WERE OVER SOUTHERN AND COASTAL AREAS OF 
CAMERON COUNTY, WITH RAINFALL TOTALS OF 2 TO 4 INCHES. THE WELCOME 
RAINS PROVIDED ONLY SHORT TERM RELIEF TO THE SEVERE TO EXCEPTIONAL 
DROUGHT CONDITIONS. EXCLUDING THIS RAIN EVENT, EXTREMELY DRY 
CONDITIONS PREVAILED DURING THE MONTH OF APRIL. ACCORDING TO THE 
NATIONAL CLIMATIC DATA CENTER (NCDC) EXCEPTIONALLY DRY CONDITIONS 
HAVE PERSISTED OVER DEEP SOUTH TEXAS DURING THE PERIOD OF OCTOBER 
2007 TO MARCH 2008. ACCORDING TO THE UNITED STATES DROUGHT MONITOR, 
EXCEPTIONAL DROUGHT CONDITIONS (D4) ARE OCCURRING OVER ZAPATA, JIM 
HOGG, WESTERN BROOKS AND NORTHERN STARR COUNTIES. EXTREME DROUGHT 
CONDITIONS (D3) PERSIST OVER HIDALGO, EASTERN BROOKS AND SOUTHERN 
STARR COUNTIES. SEVERE DROUGHT CONDITIONS (D2) ARE INDICATED OVER 
THE COASTAL COUNTIES OF KENEDY, WILLACY AND CAMERON. THE DROUGHT 
CONDITIONS ARE MAINLY AFFECTING AGRICULTURAL INTERESTS, INCLUDING 
PASTURES AND GRASSLANDS. 
HYDROLOGIC IMPACTS...
FALCON AND AMISTAD RESERVOIRS PROVIDE MUCH OF THE WATER FOR THE 
LOWER RIO GRANDE VALLEY. CURRENTLY, STORAGE AT AMISTAD IS AT 74 
PERCENT OF NORMAL CONSERVATION. STORAGE AT FALCON IS CURRENTLY AT 41 
PERCENT OF NORMAL CONSERVATION. WATER STORAGE LEVELS ARE EXPECTED TO 
CONTINUE TO DECREASE AT BOTH RESERVOIRS IN RESPONSE TO INCREASE 
DEMANDS FROM MUNICIPALITIES AND AGRICULTURAL INTERESTS.   
FIRE DANGER....
WILDFIRE DANGER CONTINUES TO BE OF GREAT CONCERN FOR DEEP SOUTH 
TEXAS. ACCORDING TO THE STATE OF TEXAS FOREST SERVICE, THE 
COMBINATION OF ABOVE NORMAL TEMPERATURES, ABUNDANT DRY FUELS, LOW 
HUMIDITIES AND MODERATE TO STRONG WINDS WILL ALLOW THE FIRE DANGER 
TO REMAIN MODERATE TO HIGH OVER DEEP SOUTH TEXAS. RECENT RAINS 
PROVIDED LITTLE RELIEF TO THE FIRE DANGER CONDITIONS. THE LATEST 
KEETCH-BYRAM DROUGHT INDICES (KBDI) ARE CURRENTLY 700 AND ABOVE OVER 
ZAPATA COUNTY, 600 TO 700 KBDI OVER STARR, JIM HOGG, BROOKS, HIDALGO 
AND KENEDY COUNTIES. KEETCH-BYRAM INDICES ARE 500 TO 600 OVER 
WILLACY AND CAMERON COUNTIES. BURN BANS ARE CURRENTLY IN EFFECT FOR 
THE ALL COUNTIES OF DEEP SOUTH TEXAS, WITH THE EXCEPTION OF KENEDY 
COUNTY. RESIDENTS OF DEEP SOUTH TEXAS ARE STRONGLY URGED TO USE 
EXTREME CAUTION WHEN DISPOSING OF SMOKING MATERIALS, AND REFRAIN 
FROM ALL OUTDOOR BURNING ACTIVITIES. 
AGRICULTURAL IMPACTS...
ACCORDING TO THE CLIMATE PREDICTION CENTER, SOIL MOISTURE OVER MUCH 
OF DEEP SOUTH TEXAS IS ABNORMALLY TO EXCESSIVELY DRY. ACCORDING TO 
THE UNITED STATES DEPARTMENT OF AGRICULTURAL, THE UNIVERSITY OF 
TEXAS A&M, TEXAS AGRILIFE EXTENSION SERVICE AGENTS...SHORT TO VERY 
SHORT MOISTURE CONDITIONS CONTINUED TO BE THE RULE THROUGH MUCH OF 
THE AREA. RECENT RAINS PROVIDED SHORT TERM RELIEF. DRYLAND CROPS 
COULD EXPERIENCE A HEAVY LOSS DUE TO THE DROUGHT CONDITIONS. CABBAGE 
AND ONION HARVEST CONTINUES. COTTON, CORN, SORGHUM, SPRING 
VEGETABLES, CANTALOUPES, AND WATERMELONS WERE MAKING GOOD PROGRESS 
UNDER IRRIGATION. PRODUCERS ARE STILL PROVIDING SUPPLEMENTAL FEED TO 
CATTLE BECAUSE OF LACK OF SPRING FORAGE. RECENT DAILY EVAPORATION 
RATES HAVE BEEN AVERAGING A QUARTER TO NEAR HALF AN INCH.
RESTRICTIONS...
ACCORDING TO THE STATE OF TEXAS COMMISSION ON ENVIRONMENTAL QUALITY 
(TCEQ), THERE ARE CURRENTLY 3 PUBLIC WATER SYSTEMS IN HIDALGO COUNTY
WHICH ARE UNDER MILD RATIONING.
OUTLOOK...(MAY 2ND - MAY 15TH)...
AN UPPER LEVEL RIDGE OF HIGH PRESSURE IS EXPECTED TO DEVELOP OVER
THE SOUTHERN PLAINS EARLY NEXT WEEK AS AN UPPER LEVEL TROUGH OF 
LOW PRESSURE OVER THE CENTRAL PLAINS MOVES EASTWARD THIS WEEKEND.
THIS WILL PROVIDE GENERALLY DRY CONDITIONS ACROSS DEEP SOUTH TEXAS 
THROUGH MAY 7TH. THE UPPER LEVEL RIDGE SHOULD WEAKEN MAY 7TH 
ALLOWING A WEAK UPPER LEVEL TROUGH TO MOVE THROUGH THE SOUTH CENTRAL 
PLAINS MAY 8TH. THIS MAY PROVIDE SOME ISOLATED SHOWER AND 
THUNDERSTORM ACTIVITY ACROSS SOUTH TEXAS MAY 8TH. AN UPPER LEVEL 
RIDGE IS EXPECTED TO BUILD ACROSS THE SOUTHERN PLAINS MAY 9TH AND 
10TH BEFORE WEAKENING ON THE 11TH. NO SIGNIFICANT RAINFALL IS 
EXPECTED FROM MAY 9TH THROUGH MAY 11TH BEFORE AN UPPER LEVEL TROUGH 
OVER THE NORTHERN PLAINS MOVES SOUTHEAST ON THE 12TH BRINGING A WEAK 
COLD FRONT INTO SOUTH TEXAS. THIS FRONT MAY PROVIDE ISOLATED TO 
SCATTERED SHOWER AND THUNDERSTORM ACTIVITY ACROSS SOUTH TEXAS MAY 
12TH. ANY RAINFALL THAT DOES OCCUR OVER DEEP SOUTH TEXAS THROUGH MAY 
15TH WILL PROVIDE ONLY SHORT TERM RELIEF FROM THE CURRENT DROUGHT 
CONDITIONS. THE OVERALL TEMPERATURES THROUGH NEXT WEEK WILL BE NEAR 
TO ABOVE NORMAL FOR DEEP SOUTH TEXAS. AVERAGE HIGHS FOR DEEP SOUTH 
TEXAS FOR EARLY TO MID MAY GENERALLY RANGE IN THE UPPER 80S TO LOWER 
90S WHILE AVERAGE LOWS FOR THE SAME PERIOD RANGE IN THE UPPER 60S TO 
LOWER 70S.            
THE LONG RANGE CLIMATE OUTLOOK FOR MAY THROUGH JULY OF 
2008...DERIVED FROM GUIDANCE FROM THE NATIONAL WEATHER SERVICE AND 
THE CLIMATE PREDICTION CENTER...INDICATES THAT WEAK TO MODERATE LA 
NINA CONDITIONS WILL LIKELY PERSIST THROUGH THE REST OF THE SPRING 
INTO THE EARLY SUMMER OF 2008. AS A RESULT OF THE CONTINUING LA NINA 
CONDITIONS...BELOW NORMAL RAINFALL WILL LIKELY BE EXPECTED ACROSS 
DEEP SOUTH TEXAS THROUGH JULY OF 2008. SOME GUIDANCE FROM THE 
CLIMATE PREDICTION CENTER INDICATES THE POTENTIAL OF THE LA NINA 
CONDITIONS WEAKENING FOR THE REST OF THE SUMMER MONTHS OF 2008. THIS 
MAY ALLOW MORE NORMAL RAINFALL AMOUNTS ACROSS THE REGION AFTER JULY 
2008. THE U.S. SEASONAL DROUGHT OUTLOOK AND OTHER GUIDANCE FROM THE 
CLIMATE PREDICTION CENTER INDICATES THAT DROUGHT CONDITIONS OVER 
DEEP SOUTH TEXAS ARE EXPECTED TO PERSIST OR INTENSIFY THROUGH JULY 
OF 2008.
FOR ADDITIONAL INFORMATION...AND THE LATEST WEATHER FORECAST FOR 
DEEP SOUTH TEXAS...VISIT OUR WEBSITE AT WWW.SRH.NOAA.GOV/BRO. YOU 
MAY ALSO VISIT THE NATIONAL WEATHER SERVICE CLIMATE PREDICTION 
CENTER WEBSITE AT WWW.CPC.NOAA.GOV AND GET THE LATEST INFORMATION ON 
RESERVOIR LEVELS FROM THE INTERNATIONAL BOUNDARY AND WATER 
COMMISSION AT WWW.IBWC.STATE.GOV.
$$
VEGA/CASTILLO