If it's really bad and power will be out for a long time, go to Walmart or any place that sells fishing supplies and buy a livewell aerator ( it's a water pump that mixes water and air). Around 30 bucks.
Hook it up to a 12 volt battery and it will circulate the water quite well.
It's a good thing to have around in these cases. Also makes moving a tank from house to house or room to room much easier too since you can aerate the buckets the fish are in.
Do not blow into the air hose. It won't hardly do anything except add CO2
to the tank and also possibly make you pop a blood vessel blowing so hard. Also, it can cause a back siphon in the line.