396 
FGUS71 KPBZ 071438
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-
049-051-061-069-077-093-103-211445-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE PITTSBURGH PA
938 AM EST THU FEB 7 2013

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

THE FLOOD POTENTIAL FOR THE PITTSBURGH HYDROLOGIC SERVICE AREA IS 
NEAR NORMAL THROUGH FEBRUARY 22. 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 CHC 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 
THE UPPER OHIO RIVER BASIN EXPERIENCED SLIGHTLY ABOVE NORMAL
PRECIPITATION DURING THE AUTUMN IN 2012.  SINCE 1 JANUARY 2013...
PRECIPITATION HAS BEEN 50%-75% OF NORMAL IN ALLEGHENY RIVER
BASIN...100%-200% OVER THE MONONGAHELA AND CHEAT RIVER...AND NEAR
NORMAL OVER THE UPPER OHIO AND MUSKINGUM BASINS.

OVER THE PAST 60 DAYS...PRECIPITATION ACROSS ALL AREAS IN THE
UPPER OHIO RIVER BASIN HAS RANGED FROM 100%-150% OF NORMAL. 

SOILS ARE CURRENTLY FROZEN ACROSS MUCH OF THE REGION BUT CONTAIN
ABOVE NORMAL SOIL MOISTURE.
 
SNOW COVER AND SNOW WATER CONTENT
SNOW COVER OVER THE REGION RANGED FROM AROUND AN INCH IN THE
LOWER ELEVATIONS AS MORE THAN 12 INCHES IN THE HIGH EVELVATION
ABOVE 3000 FEET ELEVATIONS. EVEN WITH THE FOOT OR MORE OF SNOW IN
THE HIGH ELEVATIONS...THE SNOW HAS BEEN A DRY SNOW...WITH HIGH
RATIOS OF SNOWFALL TO LIQUID. THIS RESULTS IN SNOW WATER
EQUIVALENTS BELOW 1.00 INCH IN MOST AREAS AND 1.00 TO 2.00 IN THE
CHEAT AND UPPER MONONGAHELA ABOVE 3000 FEET ELEVATION. THAT IS A
LITTLE BELOW NORMAL FOR THIS TIME OF THE YEAR.

STREAMFLOW CONDITIONS 
STREAM FLOWS FOR THE PAST 14 DAYS ARE ABOVE NORMAL TO MUCH ABOVE
NORMAL THE AREA.

ICE CONDITIONS 
LAST WEEKS WARM TEMPERATURES AND RIVER RISES HAVE REMOVED NEARLY
ALL ICE COVERAGE ACROSS ALL MAJOR RIVERS IN THE REGION.

RESERVOIR CAPACITIES
ALL RESERVOIRS IN THE USACE PITTSBURGH DISTRICT WERE USING LESS
THAN 20 PERCENT OF THEIR CAPACITY. THIS IS UP FROM THE PAST WEEK.
THE RESERVOIRS IN THE HUNTINGDON USACE DISTRICT NEAR NORMAL WINTER
POOL LEVELS. THIS IS UNCHANGED OVER THE PAST TWO WEEKS.

WEATHER AND PRECIPITATION OUTLOOK
THE OUTLOOK FOR THE NEXT 2 WEEKS HAS AN ACTIVE STORM TRACK OVER
THE AREA. THERE WILL BE RELATIVELY SMALL STORMS BUT FREQUENT ONES.
SOME OF THE PRECIPTATION MAY BE IN THE FORM OF RAIN FEBRUARY 11
AND 12...BUT AFTER THAT...ADDITIONAL PRECIP SHOULD MOSTLY BE IN
THE FORM OF SNOW. THE FLOOD POTENTIAL WILL REMAIN NEAR NORMAL.

SUMMARY...
RAINFALL IS THE PRIMARY FACTOR LEADING TO FLOODING. HEAVY OR
EXCESSIVE RAINFALL CAN CAUSE FLOODING ANY TIME OF THE YEAR...EVEN
WHERE THE FLOOD POTENTIAL IS BELOW NORMAL.

THE NEXT WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED BY
FEBRUARY 22 2013.

$$