The weather will be extremly hot to start with and then get reasonableh cool towards the end of your tour. As for kit i personally wouldn't take too much. Most of the stuff that you need will either be issued to you or you can buy there. It realy depends what part of Kabul you are going.
Yeah they are all right, it will be cold and expect snow towards the November end of your tour so want a buffalo then, but the damn hot over the summer it really is one extreme to the other.
Which is all down to Kabuls altitude. Which you'll notice the first time you go for a run and your hanging out of your hoop long before you would do in the UK.
If your at Souter their's 6 BFBS TV channels plumed into all the accommodation so it might be worth taking a cheap TV DVD combi. Think they still have the chogie stalls their for all you DVD needs.
If you at ISAF it's not as nice just a couple of TVs in the rest rooms I think.