Until your TV Region changes over from Analogue to Digital, then you will experience signal break-up due to both reduced Transmitter Power and Weather conditions.
It is not only adverse weather which can affect TV Signals, the Sun's activity can play a part as well as is the case now during fine weather.
Using a TV Signal Booster will help but it will not eradicate the problem. There will be far less problems when Digital replaces Analogue and you can check when it will happen in your Area by visiting your TV Transmitter website