Flood Potential Outlook
Issued by NWS Little Rock, AR

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FGUS74 KLZK 052203 CCA
ESFLZK

ARC001-005-009-011-013-019-023-025-029-031-039-041-043-045-049-05
1-053-055-059-063-065-067-069-071-079-083-085-089-095-097-
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HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE LITTLE ROCK AR
400 PM CST THU MAR 5 2015

...SPRING FLOOD OUTLOOK FOR MUCH OF ARKANSAS...

THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN LITTLE ROCK HAS A
HYDROLOGIC SERVICE AREA WHICH IS WHOLLY LOCATED WITHIN THE STATE OF
ARKANSAS. IT ENCOMPASSES AN AREA WHICH INCLUDES THE WHITE RIVER AND
TRIBUTARIES FROM BULL SHOALS DAM DOWNSTREAM...THE ARKANSAS RIVER AND
TRIBUTARIES FROM DARDANELLE DOWNSTREAM...AND THE OUACHITA
RIVER AND TRIBUTARIES FROM THE HEADWATERS TO THE UPPER BOUNDARY OF
THE FELSENTHAL NATIONAL WILDLIFE REFUGE. ALONG WITH THE MAIN STEM OF
THESE RIVERS...IT ALSO INCLUDES TRIBUTARIES WITH FORECAST LOCATIONS
ON THE CACHE...BLACK...SPRING...SALINE...PETIT JEAN...FOURCHE
LAFAVE...LITTLE MISSOURI...BUFFALO...LITTLE RED...AND ELEVEN POINT
RIVERS.

EXISTING CONDITIONS...

RAINFALL - PRECIPITATION TOTALS DURING THE LAST 90 DAYS FOR ARKANSAS
HAVE BEEN NEAR TO SLIGHTLY BELOW AVERAGE. WIDESPREAD AREAS IN
NORTHWESTERN AND EASTERN ARKANSAS ARE WELL BELOW AVERAGE. ONLY IN
THE EXTREME SOUTHWEST CORNER OF THE STATE DO 90-DAY TOTALS APPROACH
OR EXCEED THE AVERAGE.

SNOWPACK - SNOWPACK ESTIMATES FROM THE NATIONAL OPERATIONS
HYDROLOGIC REMOTE SENSING CENTER (NOHRSC) INDICATE A LIGHT TO MEDIUM
SNOWPACK IN ARKANSAS. DENSEST SNOWPACK RESIDES IN NORTHEAST ARKANSAS
ALONG THE EASTERN EDGE OF THE WHITE RIVER BASIN. ALTHOUGH THIS
SNOWMELT WILL LIKELY PROLONG MINOR FLOODING TO THIS AREA IN THE
SHORT TERM IT IS NOT EXPECTED TO BE HYDROLOGICALLY SIGNIFICANT WITH
REGARD TO SPRING FLOODING.

SOIL MOISTURE - SOIL MOISTURE CONDITIONS IN ARKANSAS ARE GENERALLY
NEAR NORMAL...WITH ESTIMATES BETWEEN THE 30TH AND 70TH PERCENTILE.
WITH THE CURRENT SNOWPACK ACROSS MUCH OF THE STATE...MELTING WILL
SLOWLY INCREASE THE GROUND WATER SUPPLY. IF HEAVY RAIN WAS TO OCCUR
WITHIN THE NEXT FEW WEEKS...RUNOFF WOULD BE ELEVATED.

RIVER FLOWS AND RESERVOIRS - STREAMFLOWS WERE GENERALLY NEAR NORMAL
THIS WINTER UNTIL THIS LAST HEAVY RAIN/SNOW EVENT WHICH TEMPORARILY
BROUGHT STREAMFLOWS UP INTO THE 76TH TO 90TH PERCENTILE. THIS EARLY
SPRING WINTER EVENT BROUGHT MINOR FLOODING TO THE
BLACK...WHITE...CACHE...AND OUACHITA RIVERS WHICH WILL PERSIST INTO
MID MARCH. CORPS OF ENGINEERS PROJECTS IN ARKANSAS ARE AT LEVELS
APPROXIMATING DESIGN CONDITIONS WITH NEAR 100 PERCENT OF THEIR FLOOD
CONTROL CAPACITY AVAILABLE AT THIS TIME.

WHITE RIVER BASIN...

PRECIPITATION AND SNOW MELT HAS LED TO MINOR RISES ALONG RIVERS IN
THE BLACK AND WHITE RIVER BASINS. OVERALL SOIL MOISTURE CONTENT IS
NORMAL BUT WITH RECENT PRECIPITATION MINOR FLOODING IS EXPECTED TO
PERSIST OVER THE NEXT 1 TO 2 WEEKS ON THE BLACK...LOWER WHITE RIVER
AND CACHE RIVERS IN NORTHEAST ARKANSAS.

BASED ON EXISTING SOIL MOISTURE...STREAMFLOWS...AND NORMAL SPRING
RAINFALL PATTERNS...AN AVERAGE FLOOD POTENTIAL IS EXPECTED OVER THE
BLACK AND WHITE BASINS. PERCENT OF AVAILABLE FLOOD CONTROL STORAGE
IS GIVEN BELOW.

                                            2/18   3/4
                     BULL SHOALS RES. AR    100%  100%
                         NORFORK RES. AR    100%  100%
                    GREERS FERRY RES. AR    100%  100%


ARKANSAS RIVER BASIN...

THE POTENTIAL FOR FLOOD CONDITIONS IN WESTERN ARKANSAS WILL BE NEAR
NORMAL THIS SPRING. FLOODING IN WESTERN ARKANSAS USUALLY OCCURS IN
RESPONSE TO SPECIFIC PRECIPITATION EVENTS. HOWEVER...THE ARKANSAS
RIVER MAY FLOOD IN RESPONSE TO MORE WIDESPREAD UPSTREAM CONDITIONS.
THERE ARE CURRENTLY NO INDICATIONS OF EXTREME HYDROLOGIC CONDITIONS
TO ALTER THE FLOOD POTENTIAL OF THE AREA.

CORPS OF ENGINEERS PROJECTS ARE AT LEVELS APPROXIMATING DESIGN
CONDITIONS. THEY HAVE APPROXIMATELY 99 PERCENT OF THEIR FLOOD
CONTROL CAPACITY AVAILABLE AT THIS TIME. STREAMFLOWS ALONG THE
ARKANSAS RIVER ARE NEAR TO JUST SLIGHTLY ABOVE NORMAL
CONDITIONS...WITH THE TRIBUTARIES ABOVE AVERAGE ON ACCOUNT OF HEAVY
RAINFALL EARLIER THIS WEEK. OBSERVED FLOW ALONG THE LOWER ARKANSAS
RIVER IS CURRENTLY NEAR 25000 CFS WHICH IS 33% OF NORMAL COMPARED TO
THE LONG TERM AVERAGE OF 76000 CFS FOR EARLY MARCH.

THE CLIMATE PREDICTION CENTERS SEASONAL OUTLOOK (MAR-APR-MAY) CALLS
FOR EQUAL CHANCES OF ABOVE-NORMAL...BELOW-NORMAL...AND NEAR-NORMAL
TEMPERATURES AND ABOVE-MEDIAN...BELOW-MEDIAN...AND NEAR-MEDIAN
PRECIPITATION ACROSS WESTERN AND CENTRAL ARKANSAS.

THE U.S. DROUGHT MONITOR OF FEBRUARY 24TH 2015 INDICATES
NORTHWESTERN AND WEST-CENTRAL ARKANSAS ARE EXPERIENCING ABNORMALLY
DRY (D0) CONDITIONS BUT CALLS FOR NO INTENSIFICATION OF DROUGHT
CONDITIONS DURING THE NEXT THREE MONTHS.

OUACHITA RIVER BASIN...

STREAMFLOWS ARE NORMAL TO ABOVE NORMAL IN ARKANSAS. SOIL MOISTURE
CONTENT IS NORMAL TO ABOVE NORMAL AND DUE TO RECENT SNOW AND
RAINFALL MINOR FLOODING IS FORECAST AND/OR OCCURRING OVER PORTIONS
OF THE UPPER OUACHITA. OBSERVED DAILY STREAMFLOWS AS A PERCENT OF
MEAN ARE GIVEN BELOW.

                                             3/4
OUACHITA RIVER                 CAMDEN AR    282%
OUACHITA RIVER                 MONROE LA    143%

BASED ON EXISTING SOIL MOISTURE...STREAMFLOWS...AND NORMAL SPRING
RAINFALL PATTERNS...AN AVERAGE FLOOD POTENTIAL IS EXPECTED OVER THE
OUACHITA BASIN. PERCENT OF AVAILABLE RESERVOIR FLOOD CONTROL
STORAGE IS GIVEN BELOW.


                                            3/4
                        LAKE OUACHITA AR    100%
                          DEGRAY RES. AR    100%
                         LAKE GREESON AR    100%

METEOROLOGICAL OUTLOOK...

THE 8-14 DAY OUTLOOK ISSUED BY THE NWS CLIMATE PREDICTION CENTER
INDICATES SLIGHT CHANCES OF ABOVE NORMAL PRECIPITATION AND ABOVE
NORMAL TEMPERATURES.

THE 30-DAY OUTLOOK INDICATES EQUAL CHANCES OF ABOVE...BELOW...AND
NORMAL PRECIPITATION OVER ARKANSAS WITH SLIGHTLY ABOVE AVERAGE
PRECIPITATION EXPECTED FOR THE OHIO AND UPPER MISSISSIPPI VALLEYS.
THE TEMPERATURE OUTLOOK INDICATES HIGHER CHANCES OF BELOW NORMAL
TEMPERATURES OVER THE ENTIRE MID SOUTH.

THE 90-DAY OUTLOOK INDICATES EQUAL CHANCES OF NORMAL...ABOVE
NORMAL...AND BELOW NORMAL PRECIPITATION ACROSS REGION. BELOW NORMAL
TEMPERATURES ARE EXPECTED OVER ARKANSAS AND THE REMAINDER OF THE
LOWER MISSISSIPPI VALLEY.

CONCLUSION...

THROUGH MID MARCH MINOR FLOODING WILL PERSIST AS THE SNOWPACKS
ACROSS THE STATE MELTS. THE SATURATED SOILS FROM THE LINGERING
SNOWMELT WILL PRODUCE HIGHER RUNOFF WITH ANY WEATHER SYSTEMS THAT
MOVE THROUGH THE REGION WITHIN THE NEXT FEW WEEKS. THIS SHOULD
KEEP STREAMFLOW SLIGHTLY ABOVE NORMAL HEADING INTO THE MIDDLE OF THE
SPRING.

BY APRIL/MAY...EXPECT THE NORMAL PERIODS OF HIGHLY CONVECTIVE SEVERE
WEATHER AND ASSOCIATED HIGH QUANTITIES OF RAINFALL OCCURRING
PERIODICALLY IN A SHORT PERIOD AND OVER SMALLER WATERSHEDS. ALTHOUGH
THERE ARE NO STRONG INDICATORS THAT SUGGEST AN OVERLY WET OR
SEVERELY DRY SPRING...ANY LOCALIZED HIGH INTENSITY RAINFALL CAN
CREATE FLASH FLOODING AT ANY TIME. THIS SPRING FLOOD POTENTIAL
OUTLOOK DEFINES LONG TERM RIVER FLOODING...AND DOES NOT ASSESS THE
RISK OF SHORT TERM FLOODING.

THE SPRING POTENTIAL OUTLOOK IS A ROUTINE PRODUCT. SHOULD EXCESSIVE
RAINFALL BECOME PART OF THE FORECAST AT ANY OTHER TIME OF THE
YEAR...A HYDROLOGIC OUTLOOK WILL BE ISSUED WITH EVENT SPECIFIC
INFORMATION. ALSO LOOK FOR RIVER FLOOD ADVISORIES OR FLOOD WATCHES.
IT IS VERY IMPORTANT TO REMAIN SITUATIONALLY AWARE.

FOR THE LATEST RIVER STAGE INFORMATION...FORECAST...AND WARNINGS
PLEASE VISIT OUR WEBSITE AT:

HTTP://WWW.SRH.NOAA.GOV/LZK

RIVER STAGE AND FORECAST DATA CAN BE OBTAINED BY SELECTING THE
RIVERS AND LAKES AHPS LINK UNDER THE CURRENT CONDITIONS SECTION.

$$

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