National Weather Service United States Department of Commerce
WATER RESOURCES OUTLOOK NATIONAL WEATHER SERVICE OHIO RIVER FORECAST CENTER WILMINGTON OH 1235 PM EDT Tuesday April 26 2022 THE FOLLOWING IS THE 30-DAY WATER RESOURCES OUTLOOK FOR THE MONTH OF May .WATER RESOURCES STREAMFLOW OUTLOOK... The Ohio River Forecast Center streamflow outlook for the month of May calls for generally near normal streamflows across the Ohio Valley. ..................................................................... .HYDROLOGIC FLOOD AND DROUGHT POTENTIAL... Climatologically, May is a transition month between higher than annual average springtime streamflows and lower summertime streamflows with more localized thunderstorm precipitation, but still typically sees some precipitation events with elevated streamflows and flooding. Average precipitation increases from April to May as moisture and thunderstorm activity increases, but green-up of vegetation and increased evapotranspiration (ET) begin to mitigate the impact of some of this precipitation increase. With near normal streamflows anticipated and no strong signals for very wet or very dry weather, flood potential appears near-normal with no strong signal for drought at the moment. ..................................................................... .PAST 30 DAY HYDROLOGICAL AND METEOROLOGICAL REVIEW... RAINFALL DEPARTURES... Above normal precipitation was observed in the month of April for the far southwest Ohio Valley and the far northeast Ohio Valley, with generally below normal precipitation in between. Portions of western Pennsylvania into northeast Ohio and far western New York saw 110 to 150% of normal precipitation, with 125 to 200% of normal precipitation across much of far southeast Illinois, southwest Indiana, western Kentucky, and northern portions of Middle Tennessee. 50 to 75% of normal precipitation fell from portions of eastern Indiana into western Ohio, eastern Kentucky, and the New River basin in North Carolina and Virginia. https://www.weather.gov/images/ohrfc/dynamic/latest30day.jpeg SOIL MOISTURE CONDITIONS... Soil moisture near the end of April was generally near normal across much of the Ohio Valley, with an area of above normal conditions near the 80-90th percentile in western Kentucky and northern portions of Middle Tennessee and below normal conditions near the 10-20th percentile in southern West Virginia. https://www.cpc.ncep.noaa.gov/soilmst/w.shtml STREAMFLOW CONDITIONS... Streamflow conditions at the time of posting in late April show generally near normal streamflows across the Ohio Valley. https://watermonitor.gov ..................................................................... .ATMOSPHERIC TELECONNECTION AND OSCILLATION FORECASTS FOR THE NEXT MONTH... TELECONNECTION/OSCILLATION PATTERN ARCTIC OSCILLATION Negative, becoming neutral = Below average to normal NORTH ATLANTIC OSCILLATION Negative, becoming neutral = Below average to normal PACIFIC/NORTH AMERICAN TELECONNECTION Positive becoming Neutral = Below average to normal ENSO - EL NINO/LA NINA OSCILLATION La Nina present = Average https://www.cpc.ncep.noaa.gov ..................................................................... .TECHNICAL DISCUSSION... Short to medium term models show a potential for a system to bring widespread rain to part of the region during the first week of May, but generally show a near normal precipitation signal into mid-May. At the time of issuance, CFSv2 longer term guidance does not consistently show a strong wet or dry signal for late May. Teleconnections generally show a similar story, with most favoring below normal to near normal conditions. ....................................................................... VISIT OUR WATER RESOURCES WEBSITE AT http://www.weather.gov/ohrfc/WRO IN ADDITION TO A 30-DAY STREAMFLOW OUTLOOK...YOU CAN ALSO OBTAIN A 60- AND 90-DAY OUTLOOK AT THE WEBSITE $$