Measurements taken at the Sea Cut near Scalby show water levels steadily rising throughout the day.
The latest advice from the Environment Agency is to be prepared as flooding is possible in the area.
River levels were already high in the area, combined with persistent and heavy rainfall and snowmelt has led to the flood alert.
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It follows flood warnings elsewhere in the county as Storm Christoph rolls in, as well as yellow and amber warnings for rain which is expected to last until Thursday.
At 6am this morning levels measured at 0.73m, by midday this had risen to 0.78m, and by 4pm levels had sharply risen to 0.94m.
The Environment Agency says when the water level reaches 0.70m at Scalby, minor flooding is possible in the area.
Flood alert and warnings in place for River Seven, Rye and DerwentMeasurements taken closer to the mouth of the river where it joins the sea have also showed water levels rising from 0.40m at 6.15am this morning to 0.51m by 3.30pm.
The Environment Agency says when the water level reaches 0.37m closer to the mouth, minor flooding is possible in the area.
The video used in this article is from February 2020 when the Sea Cut became a torrent due to storms.