
If you are after salmon or seatrout it is useful to know when there is a decent head of water on the river. This is relevant on the Dee but even more so on other rivers in the area which generally fish better when they are in spate.
An ideal site for this purpose is
the Environment Agency site. If you move your cursor over the map and click the area you want and it will take your to that region. You then do the same and click on the river catchment area. It will show you the river gauging stations (green dots). Click on one of these and you get the river height and a graph. If you click on an estuary you can see the tide times.

Easily accessed by phone is another useful site where you are given an automated reading of the flow level on the Dee at Manley Weir which is near Erbistock.
The phone number is 01978710398.
You will hear a tone like a fax machine, then "Power Station 133-normal-water level-one" followed by another number which is the reading. The number can range from about 300 to above 1600. A good reading for salmon is around 750. If the reading is much above this level then you may do better with a spinner rather than a fly.
An identical system gives a reading for the flow levels on the Conway by phoning 016907107728. The power station number there is 9201, otherwise the format is the same.
For weather updates try
this BBC site.