000
FGUS71 KPBZ 041516
ESFPBZ
MDC023-OHC013-019-029-031-059-067-081-111-119-121-157-PAC003-005-
007-019-031-051-053-059-063-065-073-085-121-125-129-WVC009-029-
049-051-061-069-077-093-103-181530-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE PITTSBURGH PA
1116 AM EDT THU APR 4 2013

...FLOOD POTENTIAL IS EXPECTED TO BE NEAR NORMAL...

NORMAL FLOOD POTENTIAL MEANS AT LEAST MINOR FLOODING IS POSSIBLE. 

FOR THE LONG-RANGE RIVER OUTLOOKS AND THE PROBABILITY OF EXCEEDING 
FLOOD STAGE OR THE CHANCES OF FLOODING RELATIVE TO NORMAL AT 
SPECIFIC FORECAST POINTS DURING THE NEXT 90 DAYS REFER TO 
WWW.WEATHER.GOV/OHRFC AND CLICK ON THE 90-DAY RIVER OUTLOOK IN THE 
LEFT HAND COLUMN.CLICK ON FLOOD CHANCE VS. NORMAL TO SEE THE RISK OF 
FLOODING WITH RESPECT TO NORMAL.

FLOOD OUTLOOKS ARE ISSUED BI-WEEKLY BY THE NATIONAL WEATHER
SERVICE DURING WINTER AND EARLY SPRING TO SUMMARIZE BASIN
HYDROMETEROLOGICAL CONDITIONS AND TO ASSESS THE POTENTIAL FOR
WINTER/SPRING FLOODING. THE OUTLOOKS ARE BASED ON CURRENT AND
EXPECTED CONDITIONS ACKNOWLEDGING THAT ACTUAL CONDITIONS COULD
CHANGE DURING THE OUTLOOK PERIOD.

IN ADDITION...90-DAY WATER RESOURCES OUTLOOKS ARE ISSUED MONTHLY.
FACTORS CONSIDERED IN ASSESSING FLOOD POTENTIAL ARE...

ANTECEDENT CONDITIONS

PAST PRECIPITATION 
OVER THE PAST 30 DAYS...PRECIPITATION HAS BEEN 25% TO 40% OF NORMAL  
ACROSS THE UPPER OHIO AND MUSKINGUM BASINS.

OVER THE PAST 60 DAYS...PRECIPITATION HAS BEEN 50% TO 95% OF NORMAL 
ACROSS THE UPPER OHIO AND MUSKINGUM RIVER BASINS.

OVER THE PAST 90 DAYS...PRECIPITATION HAS BEEN 50 TO 105 OF NORMAL 
ACROSS THE ENTIRE UPPER OHIO AND MUSKINGUM BASINS.

SOILS ARE CURRENTLY MOIST TO WET ACROSS MUCH OF THE REGION DUE TO
CONSISTENT LIGHT TO MODERATE PRECIPITATION ACROSS THE REGION.
 
SNOW PACK IS LIMITED TO THE MOUNTAINOUS TERRAIN OF THE CHEAT BASIN 
IN WEST VIRGINIA WITH SNOW WATER EQUIVALENTS OF UP TO 3.0 INCHES. 
ACROSS THE HEADWATERS OF THE ALLEGHENY BASIN SNOW WATER EQUIVALENTS 
LESS THAN 1/4 INCH.

STREAMFLOW CONDITIONS 
STREAM FLOWS AVERAGED NEAR NORMAL DURING MARCH ALONG TRIBUTARIES IN 
THE OHIO VALLEY. THE ALLEGHENY WATERSHED WAS BELOW NORMAL DURING THE 
LAST 30 DAYS. ON THE MAINSTEM OF THE OHIO STREAMFLOWS ARE NEAR 
NORMAL FOR EARLY SPRING.

ICE CONDITIONS 
THERE IS NO RIVER ICE OVER THE AREA.

RESERVOIR CAPACITIES
MOST RESERVOIRS IN THE USACE PITTSBURGH DISTRICT WERE GRADUALLY 
INCREASING POOL LEVELS WITH 6 OF THE 17 RESERVOIRS REPORTING FLOOD 
STORAGE CAPACITIES OF 10 PERCENT TO 43 PERCENT. THESE VALUES HAVE 
BEEN STEADILY TRENDING UP OVER THE PAST 30 DAYS AS THE USACE 
PREPARES FOR SUMMER POOLS. THE RESERVOIRS IN THE HUNTINGDON USACE 
DISTRICT ARE AT NORMAL WINTER POOL TO ALERT POOL LEVELS. THIS IS 
UNCHANGED OVER THE PAST TWO WEEKS.

WEATHER AND PRECIPITATION OUTLOOK
THE OUTLOOK FOR THE NEXT 2 WEEKS HAS A FAIRLY QUIET WEATHER PATTERN 
OVER THE REGION WITH EXPECTATIONS OF BELOW NORMAL PRECIPITATION 
THROUGH THE PERIOD. NORMAL PRECIPITATION FOR THE 14 DAY PERIOD IS 
ABOUT 1.13 INCHES. TEMPERATURES ARE EXPECTED TO AVERAGE NEAR NORMAL 
FOR THE NEXT WEEK WITH A COOLING TREND BEGINNING FOR THE LATTER HALF 
OF THE FORECAST PERIOD. NORMAL TEMPERATURES FOR THE NEXT 14 DAYS ARE 
HIGHS RANGING FROM THE UPPER 50S AND LOW 60S. LOWS IN THE 30S TO 
LOWER 40S. FLUCTUATIONS IN TEMPERATURES COULD STILL BRING 
PRECIPITATION IN THE FORM OF BOTH SNOW AND RAIN FOR THE NEXT 2 
WEEKS...THOUGH RAIN SHOULD BE PREDOMINANT. THE FLOOD POTENTIAL WILL 
REMAIN NEAR NORMAL.

SUMMARY...
ANTECEDENT CONDITIONS ARE NEAR NORMAL FOR THE OHIO RIVER BASIN. 
FUTURE RAINFALL WILL BE THE DETERMINING FACTOR FOR THE POTENTIAL OF 
FLOODING IN THE OHIO VALLEY. THE WEATHER PATTERN WILL BECOME 
INCREASINGLY ACTIVE DURING APRIL AFTER A QUIET START TO SPRING. 
THEREFORE...THE POTENTIAL FOR FLOODING IN THE OHIO VALLEY WILL BE 
NEAR NORMAL.

THE NEXT WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED BY
APRIL 18.


$$