HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
945 AM CST FRIDAY MARCH 10 2006
...SPRING FLOOD OUTLOOK...
...THE POTENTIAL FOR SPRING 2006 FLOODING IN SOUTHEAST LOUISIANA AND
SOUTHERN MISSISSIPPI IS GENERALLY AVERAGE...
INTRODUCTION...
THIS IS THE SPRING FLOOD OUTLOOK ISSUED BY THE NATIONAL WEATHER
SERVICE FORECAST OFFICE AT NEW ORLEANS/BATON ROUGE, LOUISIANA FOR
SOUTHEAST LOUISIANA, SOUTHWEST MISSISSIPPI, AND COASTAL
MISSISSIPPI. THIS PRODUCT IS INTENDED TO OUTLINE CURRENT RIVER AND
SOIL MOISTURE CONDITIONS AND TO HIGHLIGHT POTENTIAL SITUATIONS THAT
WOULD INDUCE FLOODING OR EXACERBATE DROUGHT.
ANTECEDENT CONDITIONS...
SNOWFALL HAS BEEN BELOW NORMAL ACROSS MUCH OF THE UPPER MISSISSIPPI
AND OHIO RIVER VALLEYS. DROUGHT CONDITIONS HAVE PERSISTED ACROSS
THE NORTHERN HALF OF LOUISIANA.
SOIL MOISTURE CONTENTS WERE NEAR NORMAL ACROSS SOUTHEASTERN
LOUISIANA, SOUTHWEST MISSISSIPPI, AND COASTAL MISSISSIPPI.
AT THIS TIME, MINOR FLOODING IS OCCURRING ALONG THE LOWER PEARL
RIVER IN MISSISSIPPI. STREAMFLOWS WERE MUCH BELOW NORMAL ALONG THE
MISSISSIPPI RIVER BELOW MEMPHIS, TENNESSEE.
MISSISSIPPI RIVER AND ATCHAFALAYA RIVER...
MINOR RISES OCCURRED ALONG THE LOWER MISSISSIPPI RIVER FROM CAPE
GIRARDEAU, MISSOURI TO MEMPHIS, TENNESSEE. MINOR FALLS OCCURRED
ALONG THE REMAINDER OF THE LOWER MISSISSIPPI RIVER. AT THIS TIME,
NO FLOODING IS OCCURRING OR IS FORECAST ALONG THE MISSISSIPPI.
FORECAST RAINFALL OF 2 TO 4 INCHES ACROSS THE LOWER MISSISSIPPI
RIVER VALLEY OVER THE NEXT 5 DAYS SHOULD SIGNIFICANTLY ELEVATE
STREAMFLOW CONDITIONS.
SOIL MOISTURE CONDITIONS ARE NEAR SEASONAL NORMALS ACROSS THE LOWER
MISSISSIPPI RIVER VALLEY. ALONG THE LOWER MISSISSIPPI RIVER
OBSERVED FLOWS ARE RUNNING MUCH BELOW SEASONAL NORMALS.
STREAMFLOWS ALONG THE LOWER MISSISSIPPI AND OHIO RIVERS RANGE FROM
30% OF NORMAL AT MEMPHIS, TENNESSEE TO 56% AT NATCHEZ, MISSISSIPPI.
OBSERVED FLOWS ALONG THE LOWER ATCHAFALAYA RIVER ARE RUNNING MUCH
BELOW NORMAL. THE OBSERVED PERCENT OF NORMAL STREAMFLOWS ARE GIVEN
BELOW.
3/9
VICKSBURG MS 43%
NATCHEZ MS 56%
RED RIVER LANDING LA 51%
BATON ROUGE LA 49%
NEW ORLEANS LA 42%
SIMMESPORT LA 37%
PEARL BASIN IN SOUTHEAST LOUISIANA...
SOIL MOISTURE CONDITIONS ARE NEAR NORMAL ACROSS THE LOWER PEARL
RIVER BASIN FROM SOUTH MISSISSIPPI INTO SOUTHEAST LOUISIANA.
OBSERVED STREAMFLOWS ARE RUNNING ABOVE NORMAL ACROSS THE LOWER PEARL
RIVER BASIN. THE OBSERVED PERCENT OF NORMAL STREAMFLOWS ARE GIVEN
BELOW.
3/9
MONTICELLO MS 97%
BOGALUSA LA 153%
AMITE AND COMITE RIVERS AND NORTHSHORE DRAINAGE BASINS IN SOUTH
LOUISIANA...
SOIL MOISTURE CONDITIONS ARE NEAR SEASONAL NORMALS OVER THE AMITE,
COMITE, AND NORTHSHORE RIVER BASINS. STREAMFLOWS ARE RUNNING MUCH
BELOW NORMAL. NO FLOODING IS OCCURRING OR FORECAST TO OCCUR. THE
OBSERVED PERCENT OF NORMAL STREAMFLOWS ARE GIVEN BELOW.
3/9
AMITE RIVER DARLINGTON LA 35%
AMITE RIVER DENHAM SPRINGS LA 15%
COMITE RIVER OLIVE BRANCH LA 18%
PASCAGOULA BASIN IN SOUTH MISSISSIPPI...
SOIL MOISTURE CONDITIONS ARE NEAR SEASONAL NORMALS ACROSS THE
PASCAGOULA BASIN. OBSERVED STREAMFLOWS ARE CURRENTLY RUNNING MUCH
BELOW NORMAL. NO FLOODING IS OCCURRING OR FORECAST TO OCCUR. THE
OBSERVED PERCENT OF NORMAL STREAMFLOWS ARE GIVEN BELOW.
3/9
PASCAGOULA RIVER MERRILL MS 35%
30-DAY AND 90-DAY PRECIPITATION OUTLOOK.....
THE 30-DAY METEOROLOGICAL OUTLOOK INDICATES NORMAL PRECIPITATION
ACROSS LOUISIANA AND MISSISSIPPI. NORMAL TEMPERATURES ARE EXPECTED
ACROSS SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI.
THE 90-DAY METEOROLOGICAL OUTLOOK INDICATES NORMAL PRECIPITATION
OVER SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI. ABOVE NORMAL
TEMPERATURES ARE EXPECTED ACROSS ALL OF MISSISSIPPI, WHILE NEAR
NORMAL TEMPERATURES EXPECTED ACROSS SOUTHEAST LOUISIANA.
CONCLUSION...
BASED ON OBSERVED STREAMFLOWS, EXISTING SOIL MOISTURE CONDITIONS,
AND NORMAL SPRING RAINFALL/SNOWMELT PATTERNS, AN AVERAGE FLOOD
POTENTIAL IS EXPECTED ALONG THE MISSISSIPPI RIVER AND THE
ATCHAFALAYA RIVER. THE MAGNITUDE OF FUTURE CRESTS WILL DEPEND UPON
THE AMOUNT AND EXTENT OF ANY UPSTREAM ACCUMULATIONS OF SNOW COVER
AND RESULTANT SNOWMELT, COUPLED WITH THE FREQUENCY, INTENSITY, AND
EXTENT OF SPRINGS RAINS.
BASED ON CURRENT SOIL MOISTURE CONDITIONS, OBSERVED STREAMFLOWS, AND
NORMAL SPRING RAINFALL PATTERNS, AN AVERAGE FLOOD POTENTIAL IS
EXPECTED ACROSS THE AMITE RIVER, THE COMITE RIVER, AND THE
NORTHSHORE DRAINAGE BASINS. AN AVERAGE FLOOD POTENTIAL IS EXPECTED
ACROSS THE PASCAGOULA RIVER BASIN IN MISSISSIPPI. AN ABOVE AVERAGE
FLOOD POTENTIAL IS EXPECTED ACROSS THE LOWER PEARL RIVER BASIN.
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