Pennsylvania Drought Monitor

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FGUS71 KCTP 071905
ESFCTP
PAC001-009-013-021-023-027-033-035-037-041-043-047-055-057-061-067-
071-075-081-083-087-093-097-099-105-107-109-111-113-117-119-123-133-
072359-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE STATE COLLEGE PA
205 PM EST THU MAR 7 2013

...WINTER/SPRING FLOOD POTENTIAL OUTLOOK 4...

INTRODUCTION.

DURING THE WINTER AND SPRING...THE NATIONAL WEATHER SERVICE ISSUES A
SERIES OF WINTER AND SPRING FLOOD POTENTIAL OUTLOOKS. THESE OUTLOOKS
ESTIMATE THE POTENTIAL FOR RIVER FLOODING (NOT FLASH FLOODING) ACROSS
CENTRAL PENNSYLVANIA BASED ON A CURRENT ASSESSMENT OF
HYDROMETEOROLOGICAL FACTORS WHICH CONTRIBUTE TO RIVER FLOODING.
ACROSS CENTRAL PENNSYLVANIA THESE FACTORS INCLUDE RECENT
PRECIPITATION...SOIL MOISTURE...SNOW COVER AND SNOW WATER
EQUIVALENT...RIVER ICE...STREAMFLOW...FUTURE WEATHER CONDITIONS AND
OTHERS. THIS OUTLOOK DOES NOT ADDRESS THE SEVERITY OR EXTENT OF ANY
FUTURE RIVER FLOODING.

THIS OUTLOOK COVERS THE SUSQUEHANNA RIVER BASIN INCLUDING THE WEST
BRANCH...JUNIATA...AND MUCH OF THE MIDDLE AND LOWER SUSQUEHANNA
VALLEY. ALSO COVERED ARE PORTIONS OF THE UPPER AND LOWER ALLEGHENY
BASINS...INCLUDING AREAS FROM WARREN AND MCKEAN COUNTIES IN THE
NORTH...THROUGH CAMBRIA AND SOMERSET COUNTIES IN THE SOUTH.

THIS OUTLOOK IS VALID THURSDAY MARCH 7TH THROUGH THURSDAY MARCH 21ST 
2013.

IN CENTRAL PENNSYLVANIA...HEAVY RAINFALL IS THE PRIMARY FACTOR WHICH
LEADS TO RIVER FLOODING. IT IS IMPORTANT TO NOTE THAT HEAVY RAINFALL
CAN RAPIDLY CAUSE RIVER FLOODING ANY TIME OF THE YEAR...EVEN WHEN
OVERALL RIVER FLOOD POTENTIAL IS CONSIDERED LOW OR BELOW AVERAGE.

DETAILED DISCUSSION.

TWO WEEK RIVER FLOOD POTENTIAL...THE CURRENT POTENTIAL FOR RIVER 
FLOODING IS CONSIDERED BELOW AVERAGE.  NO WIDESPREAD HEAVY RAIN 
EVENTS ARE ANTICIPATED FOR THE NEXT WEEK.  IN GENERAL TEMPERATURES 
LOOK TO BE CLOSE TO AVERAGE...WITH BOTH WARM AND COOL PERIODS 
EXPECTED. AN ACTIVE STORM TRACK WILL BRING IN A WEATHER SYSTEM EARLY 
NEXT WEEK WITH WIDESPREAD RAINFALL EXPECTED. NO ICE ISSUES ARE 
EXPECTED AS ALL RIVERS AND STREAMS ARE FREE FLOWING. FACTORS WHICH 
CONTRIBUTE TO RIVER FLOOD POTENTIAL ARE ADDRESSED INDIVIDUALLY BELOW.

CURRENT FLOODING...NONE.

RECENT PRECIPITATION...BELOW AVERAGE.
PRECIPITATION WITHIN THE STATE COLLEGE FORECAST AREA AREA DURING THE 
LAST 30 DAYS (FEBRUARY 5 2013- MARCH 6, 2013) IS BELOW AVERAGE 
ACROSS THE ENTIRE AREA. 

SNOW CONDITIONS...VARIABLE.
THE SOUTH CENTRAL MOUNTAINS AND LAUREL HIGHLANDS REPORTS SNOW WATER 
EQUIVALENT VALUES BETWEEN 0.50 AND 1.50 INCHES WITH DEPTHS OF 3 TO 
18 INCHES. CENTRAL PENNSYLVANIA IS REPORTING JUST TRACE AMOUNTS OF 
SNOW FALL. NORTHERN PENNSYLVANIA IS REPORTING GENERALLY UNDER ONE 
INCH OF SNOW WATER EQUIVALENT WITH DEPTHS UNDER 6 INCHES. IN THIS 
REGION THIS IS CONSIDERED BELOW AVERAGE.

SNOW DATA AND INFORMATION SOURCES INCLUDE THE NOAA/NWS OPERATIONAL 
HYDROLOGIC REMOTE SENSING CENTER (WWW.NOHRSC.NOAA.GOV)...THE U.S. 
ARMY CORPS OF ENGINEERS...NWS COOPERATIVE OBSERVERS...THE COMMUNITY 
RAIN, HAIL AND SNOW NETWORK (COCORAHS) AND OTHERS. SNOW DEPTH AND 
BASIN AVERAGE WATER EQUIVALENT ESTIMATES CAN BE SEEN AT 
WWW.ERH.NOAA.GOV/ER/MARFC AND WWW.NOHRSC.NOAA.GOV.

RIVER ICE...BELOW AVERAGE.
NO RIVER ICE IS OBSERVED ACROSS THE REGION.

FOLLOW RIVER ICE CONDITIONS AT
HTTP://ERH.NOAA.GOV/CTP/HYDRO/RIVERICE/INDEX.PHP (LOWER CASE)

STREAMFLOW CONDITIONS...VARIABLE BUT MOSTLY BELOW AVERAGE.
STREAM FLOWS ARE BELOW AVERAGE ACROSS NORTHERN PENNSYLVANIA RIVERS 
AND STREAMS. THEY ARE FLOWING CLOSER TO AVERAGE ACROSS THE SOUTHERN 
PORTIONS OF THE AREA.

REAL TIME WATER DATA IS AVAILABLE FROM THE UNITED STATES GEOLOGICAL
SURVEY BY VISITING HTTP://WATER.USGS.GOV ON THE INTERNET.

SOIL MOISTURE CONDITIONS...NEAR AVERAGE.
THE LATEST SOIL MOISTURE REPORTS SHOW THE REGION REPORTING SOIL 
MOISTURE VALUES VERY CLOSE TO AVERAGE.

MOISTURE MONITORING CHARTS
FROM NOAA'S CLIMATE PREDICTION CENTER CAN BE FOUND AT
WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/ (CHOOSE SOIL MOISTURE) AND
WWW.DROUGHT.GOV.

GROUND WATER...AVERAGE.
MONITORING WELLS INDICATE THAT CURRENT GROUND WATER LEVELS ARE ALL 
NORMAL FOR CENTRAL PENNSYLVANIA. CURRENT GROUND WATER CONDITIONS 
BASED ON A 30 DAY MOVING AVERAGE CAN BE FOUND AT 
HTTP://PA.WATER.USGS.GOV/MONITOR/GW/INDEX.HTML

RESERVOIR CONDITIONS...AVERAGE.
MOST WATER SUPPLY RESERVOIRS WITHIN CENTRAL PENNSYLVANIA ARE HOLDING
AVERAGE STORAGES FOR THIS TIME OF YEAR...AS ARE MOST FLOOD CONTROL
RESERVOIRS.

FUTURE WEATHER CONDITIONS.
TEMPERATURES ARE EXPECTED TO WARM TO ABOVE AVERAGE READINGS FOR THIS 
WEEKEND. A COLD FRONT WILL BRING A PERIOD OF RAIN FOLLOWED BY 
TEMPERATURES CLOSE TO AVERAGE FOR EARLY NEXT WEEK AND CONTINUING FOR 
SEVERAL DAYS.  

THE 6 TO 10 DAY OUTLOOK FOR THE PERIOD MARCH 12 THROUGH MARCH 16 IS 
FOR BELOW AVERAGE TEMPERATURES AND ABOVE AVERAGE PRECIPITATION. THE 
8 TO 14 DAY OUTLOOK FROM MARCH 14 THROUGH MARCH 20 IS FOR BELOW 
AVERAGE TEMPERATURES AND AVERAGE PRECIPITATION.

ADVANCED HYDROLOGIC PREDICTION SERVICE (AHPS)...BELOW AVERAGE. 
ANOTHER TOOL USED TO ASSESS THE POTENTIAL FOR RIVER FLOODING IS THE 
ADVANCED HYDROLOGIC PREDICTION SERVICE...AHPS. AHPS GENERATES 
PROBABILISTIC RIVER FORECASTS BASED ON CURRENT BASIN 
CONDITIONS...INCLUDING RIVER LEVELS...SOIL MOISTURE...EXTENT AND 
CONDITION OF ANY SNOWPACK...ALONG WITH 50 YEARS OF HISTORIC 
TEMPERATURE AND PRECIPITATION DATA. FOR THIS OUTLOOK PERIOD...AHPS 
INDICATES THAT THE LIKELIHOOD OF RIVER FLOODING IS ABOUT NORMAL 
COMPARED TO WHAT HAS BEEN HISTORICALLY OBSERVED DURING THIS SAME 
TIME PERIOD. RIVER INFORMATION CAN BE FOUND WEATHER.GOV/AHPS

SUMMARY OF FLOOD POTENTIAL MARCH 7 - MARCH 21 2013:  NO WIDESPREAD 
SIGNIFICANT FLOODING IS EXPECTED AT THIS TIME.

OVERVIEW:

CURRENT FLOODING...NONE.
RECENT PRECIPITATION...BELOW AVERAGE.
SNOW CONDITIONS...VARIABLE.
RIVER ICE...BELOW AVERAGE.
STREAMFLOW CONDITIONS...VARIABLE.
SOIL MOISTURE CONDITIONS...AVERAGE.
GROUND WATER...AVERAGE.
RESERVOIR CONDITIONS...AVERAGE.
AHPS...BELOW AVERAGE.
OVERALL FLOOD POTENTIAL...BELOW AVERAGE.

THE NEXT REGULARLY SCHEDULED WINTER/SPRING FLOOD POTENTIAL OUTLOOK 
OF THE SEASON WILL BE ISSUED ON MARCH 21ST. OTHER 
HYDROMETEOROLOGICAL INFORMATION CAN BE FOUND BY VISITING THE STATE 
COLLEGE INTERNET HOMEPAGE AT WEATHER.GOV/STATECOLLEGE.

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