The Environment Agency (EA) has issued a flood warning in Calderdale.
A flood warning is in place at Walsden Water near Todmorden, flood warnings are issued when flooding is expected and immediate action is required.
In Calderdale, around Todmorden, river levels are rising as a result of persistent heavy rainfall which brings with it a risk of flooding.
The EA said: "Areas most at risk are properties in Walsden, especially around the station.
The railway line will also flood.
The levels are expected to peak just after mid-day but will remain high throughout Saturday afternoon before they start to fall in the early evening.
"We are closely monitoring the situation and our incident response staff are sounding flood sirens and have patrols in the Upper Calder area.
"Please do not walk or drive through fast moving water. This message will be updated by 7pm, or as the situation changes."
There are also two flood alerts in place throughout the region at River Colne, Holme and Fenay Beck near Huddersfield and the Upper Calder River catchment near Halifax.
Less serious than a warning, a flood alert means flooding is possible and to be prepared.
At River Colne, Holme and Fenay Beck, the EA says areas most at risk are low lying land and roads and they advise people to avoid using low lying footpaths near local watercourses and do not walk or drive through fast moving water.
For the Upper River Calder catchment, the EA have said: "Levels at Todmorden are expected to peak around 11am but will remain high through the afternoon.
"Our staff have cleared trash screens in the Upper Calder Valley in advance of this rain. Due to the Mytholmroyd Flood Alleviation Scheme being under construction, the demountable flood defences have been put in place and will remain in place this week due to the unsettled forecast.
"Please stay aware of your surroundings and do not put yourself at risk.
"Keep an eye on the local weather forecast. This message will be updated by 5pm or as the situation changes."
The Todmorden flood group has said: "River levels are increasing, can dog walkers and those who use the canal please avoid using them as the waters are rising and footpaths are water logged."
Calderdale Council tweeted: "As expected, river levels are increasing. A Flood Alert has been issued by the EA for the Upper River Calder catchment. Walsden is triggering a warning which means the sirens will sound. We are closely monitoring the levels and will keep you posted. Be prepared."
Further flood warnings are issued throughout Yorkshire. Check the full list here: