465  
FGUS71 KBGM 101651  
ESFBGM  
NYC007-015-017-023-025-053-065-067-077-097-099-101-105-107-109-  
123-PAC015-069-079-103-115-127-131-121700-  
 
WINTER/SPRING FLOOD POTENTIAL OUTLOOK  
NATIONAL WEATHER SERVICE BINGHAMTON NY  
1151 AM EST THU JAN 10 2019  
 
...BELOW AVERAGE FLOOD POTENTIAL FOR CENTRAL NEW YORK AND  
NORTHEASTERN PENNSYLVANIA...  
 
THIS IS THE FIRST IN THE SERIES OF REGULARLY SCHEDULED HYDROLOGIC  
OUTLOOKS ISSUED DURING THE WINTER AND SPRING SEASON. THIS OUTLOOK  
IS DESIGNED TO PROVIDE A GENERALIZED ASSESSMENT OF RIVER FLOOD  
POTENTIAL (NOT FLASH FLOODING) ACROSS CENTRAL NEW YORK AND  
NORTHEAST PENNSYLVANIA FOR THE NEXT TWO WEEKS...JANUARY 10TH  
THROUGH JANUARY 24TH.  
   
..SUMMARY
 
 
THE WINTER/SPRING FLOOD POTENTIAL FOR CENTRAL NEW YORK AND  
NORTHEAST PENNSYLVANIA IS CONSIDERED BELOW AVERAGE ACROSS THE  
MAJOR BASINS FOR THE NEXT TWO WEEKS. WHEN GROUND, AND RIVER  
CONDITIONS ARE CONSIDERED BELOW NORMAL, IT TYPICALLY TAKES IN  
EXCESS OF 2-3 INCHES OF RAINFALL WITHIN 12 TO 24 HOURS TO CAUSE  
SIGNIFICANT FLOODING.  
   
..CURRENT CONDITIONS
 
 
.PRECIPITATION: ABOVE AVERAGE. THE PAST TWO WEEKS HAVE SEEN AN  
AVERAGE OF 1 TO 2 INCHES OF RAINFALL IN THE REGION, WITH GENERALLY  
AN INCH OR LESS IN THE CHEMUNG AND FINGER LAKES BASINS, AND A  
TOUCH MORE FROM THE NEVERSINK BASIN INTO THE UPPER MAIN STEM OF  
THE DELAWARE RIVER. THESE AMOUNTS MAKE UP A HIGHER THAN AVERAGE  
DEPARTURE OF 125 TO 150 PERCENT OF NORMAL.  
 
.SNOW COVER AND WATER EQUIVALENT: BELOW NORMAL. SNOW DEPTH ACROSS  
THE AREA HAD RECENTLY INCREASED WITH MOST OF THE AREA SEEING  
DEPTHS OF 1 TO 3 INCHES, EXCEPT FOR NORTHEAST PA AND IN THE  
CHEMUNG BASIN WHERE SNOW COVER WAS PATCHY. FURTHER NORTH AND EAST  
FROM THE FINGER LAKES TO THE HEADWATERS OF THE SUSQUEHANNA NORTH  
BRANCH AND OSWEGO BASINS, SNOW DEPTHS RANGED FROM 3 TO 7 INCHES.  
SNOW WATER EQUIVALENT VALUES WERE AVERAGING AROUND ONE-HALF INCH  
IN THESE AREAS WITH LOCALLY UP TO AN INCH POSSIBLE.  
 
.RIVER ICE COVER: BELOW NORMAL. LITTLE TO NO ICE WAS OBSERVED ON  
AREA RIVERS AND TRIBUTARIES. THIS IS NOT TYPICAL FOR MID-JANUARY.  
 
.STREAMFLOW: ABOVE NORMAL. STREAMFLOW, AVERAGED OVER THE PAST FOUR  
WEEKS, WAS GENERALLY ABOVE NORMAL FOR A LARGE PORTION OF THE  
UPPER DELAWARE, SUSQUEHANNA AND CHEMUNG BASINS. THE FINGER LAKES,  
OSWEGO BASIN AND SOME OF THE WEST BRANCH DELAWARE BASINS WERE  
FLOWING NEAR, TO SLIGHTLY ABOVE, NORMAL WHEN COMPARED TO THE LONG  
TERM HISTORY OF EACH GAUGE.  
 
.SOILS AND GROUNDWATER: ABOVE NORMAL. THE PALMER DROUGHT SEVERITY  
INDEX, ALONG WITH OTHER MULTI-MODEL SOIL MOISTURE INDICATORS,  
SHOWED WETTER THAN AVERAGE DEEP SOIL CONDITIONS THROUGHOUT THE  
REGION. A MAJORITY OF GROUNDWATER INDEX STATIONS WERE REPORTING  
ABOVE NORMAL LEVELS.  
   
RESERVOIR AND LAKE LEVELS
 
ABOVE NORMAL. NYC RESERVOIRS, THE FINGER  
LAKES, AND LAKE WALLENPAUPACK WERE ALL GENERALLY CONSIDERED TO BE  
HIGHER THAN THEIR AVERAGE MID-WINTER POOL ELEVATIONS.  
   
..FORECAST OUTLOOK
 
 
.FUTURE WEATHER CONDITIONS: THE OFFICIAL 6 TO 14 DAY OUTLOOK  
CALLS FOR AVERAGE TO COLDER THAN AVERAGE TEMPERATURES.  
PRECIPITATION LOOKS TO BE BELOW AVERAGE DURING THE FIRST WEEK,  
TRENDING TOWARD ABOVE AVERAGE IN THE SECOND WEEK. LONG RANGE  
ATMOSPHERIC MODEL AND ENSEMBLE GUIDANCE SUGGESTED A SIMILAR TREND  
IN TEMPERATURES, ALTHOUGH FOCUSED ON DRIER THAN NORMAL CONDITIONS  
FOR MOST OF THE UPCOMING TWO WEEKS. A STORM SYSTEM, THAT COULD  
BRING SIGNIFICANT PRECIPITATION TO THE AREA, IS PROJECTED DURING  
THE WEEKEND OF JANUARY 18-20. ITS TOO EARLY TO TELL IF THIS  
WOULD BE RAIN, OR A WINTRY MIX.  
 
.LONG RANGE RIVER MODELING AND PROBABILITY FORECASTS: THE  
ENSEMBLE OF RIVER FORECAST SYSTEMS INDICATED LESS THAN A 5 PERCENT  
CHANCE OF FLOODING DURING THE NEXT 10-14 DAYS. ANOTHER ANALYSIS  
OF FLOODING CHANCES, USING CURRENT HYDROLOGIC CONDITIONS COMPARED  
TO HISTORICAL FLOWS, INDICATED LOWER THAN AVERAGE CHANCES FOR  
FLOODING IN MOST OF THE BASINS THROUGH JANUARY. STATISTICS IN THE  
UPPER DELAWARE BASIN SHOWED CLOSER TO NORMAL CHANCES FOR FLOODING  
GIVEN THE ANTECEDENT CONDITIONS.  
   
..IN CONCLUSION
 
 
THIS OUTLOOK ESTIMATES THE POTENTIAL FOR RIVER AND LAKE FLOODING  
BASED ON A CURRENT OVERVIEW OF HYDRO-METEOROLOGICAL FACTORS WHICH  
CONTRIBUTE TO FLOODING.  
 
IT IS IMPORTANT TO NOTE THAT SIGNIFICANT FLOODING DOES NOT OCCUR  
FROM SNOW MELT AND ICE JAMS ALONE. RAINFALL, HOW MUCH AND IN HOW  
SHORT A PERIOD OF TIME, IS THE MOST IMPORTANT FACTOR IN  
DETERMINING THE SEVERITY OF FLOODING. SPECIFIC FORECASTS OF HEAVY  
RAINFALL AND FLASH FLOODING ARE NOT INCLUDED IN THIS OUTLOOK.  
 
THE NEXT WINTER/SPRING FLOOD OUTLOOK WILL BE ISSUED BY THIS  
OFFICE IN TWO WEEKS, ON JANUARY 24TH, 2019. IF CONDITIONS CHANGE  
IN THE INTERIM: FLOOD WATCHES, WARNINGS OR ADVISORIES WILL BE  
ISSUED AS NECESSARY.  
 

 
 
JAB  
 
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