Clear water winter barbel

Ok, so down south we've had bugger all in the way of rain and this will probably continue for a couple of months.
However, it will get cold.
So how do I tackle the barbel when the water temperature drops but the level is still stupidly low?

The simple answer is - after dark. The more clear the water the more inclined they'll be to wait until darkness falls before feeding.

If you have no choice but to fish in daylight then use a long fluoro hooklength (3ft to 5ft), maggot or caster as bait on a 14's or 16's Drennan Super Spade, and a swimfeeder approach.

If it drops below about 45 and keeps on a downward trend - fish for chub!

Wait for the water temp to rise is the simple anwser! Low clear water and dropping temp is the kiss of death for Barbel. If ever a day had B-L-A-N-K written on it, thats it. As Graham mentions 45? seems to be the accepted starting line but basically if its going up then you have a chance.