Search, rescue and clean-up will be hampered in Christchurch when rain and colder winds return on Friday. Friday is likely to be the coldest day in more than a month with the temperature struggling to get past the mid teens. This will be about five degrees cooler than the end-of-February average maximum of 21. Regarding rain, there shouldn't be too much, in the order of two to five millimetres, but together with colder southerly winds it will add to the discomfort and possibly slow down the rescue process. Once the rain clears on Friday night it will cool down fairly quickly, dipping to seven or eight degrees by early Saturday morning. It's looking like the coldest night in a week and a half. The rain which has been falling is now clearing under a weak high pressure ridge. Thursday will become sunnier and a little warmer with the temperature reaching the low 20s. On Friday a front will bring a brief burst of showery southerlies. From Saturday dry, sunnier and warmer weather will then last until at least mid-next week. Tropical Cyclone Atu, approaching from the north, should stay far enough from New Zealand to not cause severe weather anywhere in the country.