OHRFC Decision Support – Winter/Spring Flood Potential Outlook
WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE
OHIO RIVER FORECAST CENTER WILMINGTON OH
957 AM EDT Wednesday January 31 2024
...Flood Potential for the next two weeks is normal with lingering flood waters remaining in the western basin for week 1. Week 2 looks to bring back an active weather pattern allowing for potential new rises...
...Winter/Spring Flood Outlook for the 2024 flood season, edition 3...
PAST PRECIPITATION THE LAST 14 DAYS...
Rainfall over the past 14 days can once again be broken into 2 distinct periods with drier conditions present for mid January before we transitioned to the active and wet pattern for the past week (end of January). 2 weeks ago featured the transition from the deep freeze to a more seasonal pattern by early last week. We then got into the series of weather systems that brought our latest significant river rises across the Ohio Valley.
While the numbers signify that much of the region sat well above normal with precipitation for the past 14 days, it was really the past week that dominated the statistics. Looking closer at the noted period we see the vast majority of the region sat at or above normal for the past 14 days worth of precipitation (150-300%). The only region to fall below normal would be the headwaters of the New and Greenbrier River basins along with the headwaters of the Monongahela basin in the high terrain of West Virginia.
For more information please visit:
https://urldefense.com/v3/__https://water.weather.gov/precip__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4ptcrIQhc$
SOIL MOISTURE...
Soil moisture continued to slowly push towards normal as we moved through January. While frozen ground prohibited an abundance of infiltration, some did occur as the ground slowly thawed from our period of frigid temperatures. While much of the region still shows below normal moisture anomalies, improvement is occurring. Even with the recent rains, much of the southern and western Ohio Valley sits below normal for soil moisture metrics.
State rankings:
Southeast Illinois - Slightly below normal
Indiana - Below normal
Ohio - Below normal northwest, normal remainder of state
Western Pennsylvania - Normal to slightly above normal
West Virginia - Below normal west, normal remainder of state
Kentucky - Slightly below normal
Tennessee - Slightly below normal
For more information please visit:
https://urldefense.com/v3/__https://www.cpc.ncep.noaa.gov/products/Drought/Monitoring/smp.shtml__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4pdjK2qLI$
USGS STREAMFLOWS...
The past seven-day streamflows have been normal to above normal for the Ohio Valley.
State rankings:
Southeast Illinois - Slightly above normal
Indiana - Slightly above normal
Ohio - Above normal
Western Pennsylvania - Above normal
West Virginia - Above normal
Kentucky - Normal
Tennessee - Normal
For more information please visit:
https://urldefense.com/v3/__https://watermonitor.gov__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4pqYBAyTA$
RESERVOIR CONDITIONS...
Reservoirs in the region are slightly elevated due to recent rains. Given a prolonged dry period for the upcoming week, stored water will have ample time to be released allowing a return to near winter pools. Even with elevated pools, ample storage remains available for any flood management, if necessary.
OHIO RIVER FLOWS...
The current Ohio River flows indicate elevated flows throughout the entire course of the river.
Values are in percent of normal with above 100% are above normal and below 100% are below normal.
Pittsburgh - 300%
Huntington - 310%
Cincinnati - 275%
Louisville - 250%
Evansville - 225%
Smithland - 200%
SNOW WATER CONTENT IN SNOWPACK...
An abundance of the snowpack was lost during the past 7 days due to above normal temperatures and rounds of precipitation. At this point we only have limited pockets in the mountains in the east and also some near the eastern Lake Erie shoreline.
For more information please visit:
https://urldefense.com/v3/__https://www.nohrsc.noaa.gov/nsa__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4pYoqO3cM$
ICE COVER...
No ice is present in the Ohio Valley. All ice that was present from last week has melted or been flushed downstream.
2-WEEK FUTURE RAINFALL AND FLOOD OUTLOOK SUMMARY...
Overall discussion...
The next couple weeks follows the pattern of 2 very different periods. The upcoming week looks generally dry across the Ohio Valley as an area of high pressure builds in the region promoting a split storm track. Models as of right now have a system passing mainly to our south early next week. Energy will also pass to our north, but the vast majority of the region remains dry. By the time we reach the tail end of next week, the pattern looks to be shifting to have the ridge slide east allowing the storm track to once again pass over the Ohio Valley. While this is at the tail end of the model runs, most have been hinting at this pattern change for a couple days now. CPC outlooks are also signaling some form of change with a transition back to better odds of above normal precipitation.
Given the upcoming dry period for the next week, this will provide time for rivers that are currently elevated to fall back towards normal values. Reservoirs will also have a good amount of time to release any stored water. If the transition back to above normal precipitation does occur, potential river rises will need to be monitored.
OHIO RIVER AVERAGE FLOW FORECASTS THE NEXT 2 WEEKS...
Flows currently sit above normal as the wave moves downstream from the weekend rains. As of current (1/31/24 at 10am) the crest sits around Huntington, WV. We drop to normal throughout the week and a half before another potential rise is possible by the middle of February.
Values are in percent of normal with greater than 100% being above normal and values below 100% being below normal.
Pittsburgh - 200%
Huntington - 200%
Cincinnati - 150%
Louisville - 150%
Evansville - 200%
Smithland - 200%
For more information on the 10-day flood risk potential please visit:
https://urldefense.com/v3/__https://www.weather.gov/erh/mmefs__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4pV_xK8c4$
Official forecasts can be found at:
https://urldefense.com/v3/__https://www.weather.gov/ohrfc__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4pAE5xISc$
ADDITIONAL INFORMATION...
Flood risk is defined as follows:
Below normal - flooding will be limited
Normal - minor flooding in the typical locations
Above normal - widespread flooding with some moderate or major possible
Winter/spring flood outlooks are issued weekly by the National Weather Service Ohio River Forecast Center during winter and early spring to summarize basin hydrological and meteorological conditions. It also assesses the potential for flood risk. The outlooks are based on current and forecast conditions.
The Ohio River Forecast Center also issues a 30-90 day water resources outlook monthly throughout the year for a continuous water watch. This can be found at https://urldefense.com/v3/__https://www.weather.gov/ohrfc/wro__;!!IEUkHoJtBip-!-QBmq0Znj8lLi1em1FAxChJidwZUAfMGcSQQHxanQEq90faBAsa63w-hitUXK-LKO_o-n0JrzCYYFSqW3k4ppUo7JlU$
Factor considered in assessing flood potential include antecedent conditions, past precipitation, current streamflows and reservoir levels, soil moisture, water content in snow cover, ice conditions and future precipitation.