DYFED Powys Police is preparing for heavy rainfall after a weather warning was issued for Powys.
The force is also urging the public to check weather forecasts and take precautions to minimise the risk of heavy rainfall and potential flooding.
The Met Office has issued a yellow, "be prepared" warning for heavy rain through Wednesday into Thursday.
Dyfed Powys Police said it is expecting high levels of demand on its contact centre and control room as the weather worsens. It says people seeking advice on the weather should check weather forecasts in the media, on the internet and social media or if the Traffic Wales website www.traffic-wales.com for traffic and travel advice.
Police also reissued their appeal to motorists to observe road closures following a number of incidents where drivers had to be rescued when their cars became stuck in flood waters.
Information and advice on flooding follow is available from the Natural Resources Wales website http://naturalresources.wales/4043.aspx?lang=en
Chief Superintendent Aled Davies said: "We are urging everyone to be aware and take sensible steps to keep themselves and others safe on the roads.
"There are already stretches of road throughout the force area that are either under water, or are very wet, making driving conditions dangerous.
"We are appealing to all motorists to heed road signs indicating a road is closed or flooded, as there have been examples this week where emergency services have been heavily committed, dealing with incidents where people have ignored these signs and got into difficulty in deep water.
"Please help keep yourself and emergency services staff safe by abiding with road signs, and listening to advice issued by agencies."
Natural Resources Wales said prolonged period of heavy rain have already left the ground saturated. There is also a risk leaves and other debris, brought down by strong winds, will block drains causing flooding of road surfaces. It advised people to allow extra time for journeys as driving conditions may be difficult.
Mike Thompson, from the agency, said: "We’re asking people to take care and regularly view our flood alerts and warnings, updated every 15 minutes on our live flood warning map available on our website.
"With more wet weather forecast it is also advisable to check local weather reports and news for any disruption in your area.
"If you want to find out if you are at risk of flooding, or want to sign up for our free Flood Warning service, please visit our website or call Floodline on 0345 988 1188."