000 FGUS71 KBGM 301946 ESFBGM NYC007-011-015-017-023-025-053-065-067-077-097-099-101-105-107- 109-123-PAC015-069-079-103-115-127-131-042000- Winter/Spring Flood Potential Outlook National Weather Service Binghamton NY 346 PM EDT Thu Mar 30 2023 ...AVERAGE FLOOD RISK THROUGH APRIL 13TH... This is the sixth (and final) edition, in the series of regularly scheduled Hydrologic outlooks issued during the Winter to Spring transition season. This outlook is designed to provide a general overview of river flood potential (not flash flooding) across Central New York and Northeast Pennsylvania through April 13th. ...SUMMARY... The flood potential for the NWS Binghamton hydrologic outlook area is about average for late March and early April. ...CURRENT CONDITIONS... UPPER SUSQUEHANNA AND UPPER DELAWARE BASINS... Recent Precipitation: The majority of the area exhibited below average precipitation over the past two weeks with the southern half of these basins receiving only 25-50% of normal precipitation. Precipitation for the entire month of March remained near to above normal. Snow Cover: A near to slightly above average snowpack remains across the higher terrain and deeply forested areas of the basins with mostly none across the Pennsylvania portion of the basins. Snow Water Equivalent: The water equivalence of the snowpack is near to above average where snow currently exists. Between 1-2 inches of liquid remains at the higher elevations in the Upper Delaware, but generally less than a half inch elsewhere. Streamflows: River flows averaged over the past two weeks varied from normal to slightly above normal. River Ice: No ice remains on the major rivers and tributaries, which is normal at this time of year. Ground State: Soil moisture is generally wetter than normal across the northern half of these basins, while normal to slightly drier than normal in southern and western areas. SENECA/OSWEGO BASINS... Recent Precipitation: Precipitation was near to above average over the past two weeks and in some areas reached about 125% of normal. Precipitation for the entire month of March remained above normal. Snow Cover: There is little to no snowpack in the basins outside of the Tug Hill plateau where 8-18 inches remains in some areas. Snow Water Equivalent: The water equivalence of the snowpack is near to below average where snow currently exists. Between 1-2 inches of liquid remains across the Tug Hill/Western Mohawk drainage. Streamflows: River flows and lake levels averaged over the past two weeks varied from near to above normal. River Ice: No ice remains on the major rivers and tributaries, which is normal at this time of year. Ground State: Soil moisture is generally wetter than normal throughout these basins. ...METEOROLOGICAL AND HYDROLOGIC FORECAST OUTLOOK... FUTURE WEATHER CONDITIONS: The official 6 to 14 day outlook suggests warmer than normal temperatures and above average precipitation. Meteorological models also suggest a generally warmer than average temperature profile with a series of minor weather systems moving through the west of the basins. This will bring periods of shower activity to the region every few days, but no excessive rainfall events are anticipated. LONG RANGE RIVER MODELING AND PROBABILITY FORECASTS: The ensemble of river forecast system guidance suggests up to a 50 percent chance of river flooding at our headwater and more sensitive upper basin forecast gages. This is especially true during the first few days of this outlook period with a trend toward more normal chances for the remainder of the period. When comparing current hydrologic forecast modeling against historical flows, nearly all the river gages are tracking below the long term average risk. The probability of exceeding flood stage this time of year ranges from 30 to 50 percent. ...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. This bi-weekly flood risk is overall near normal for late March and early April. Remember that heavy rainfall is the most important factor in determining when flooding will develop and how severe the flooding may be in our area. If conditions change over the next few weeks, Flood Watches, Warnings or Advisories will be issued as necessary. This is the final outlook for the 2023 Spring flood season. These outlooks will begin again in January 2024. $$ JAB