it will get warm soon...

...well, nobody in Tokyo area would buy this seeing the current weather conditions. But, you can trust me, summer will knock on the door and the island will open them. So, I expect temperatures hitting the 30 C mark in a few weeks for sure. As most of you know, I am not the "hot weather guy" at all. In fact, I ran all my PB's in quit cool conditions with single digit Celsius readings.
But, I have to face the hot and humid climate here in Japan. Luckily, the air is quit fresh at the sea and not polluted. Looking at my running diary from last year I briefly checked how much water I lost during various runs. On Sa, 27.8.07 the temperature was 32 C and I ran 20k in 1:32 (4:36 pace Crescendo). I lost 3kg weight and I did not drink anything during the run. Next day I ran 20k in 1:45 (5:20 pace) and I lost 3,2kg. Most of this loss is water, I assume.
Next weekend I ran 35k in 2:53 (4:44 pace) in the early morning. Temperature went up from 19 C to 27 C and I lost 3kg while adding 1kg of water during the run. That is a total loss of 4kg during the 3hrs. What I noted is that my morning weight dropped by 2kg during these weeks. I assume that this is some water loss and not associated with a loss in body mass.
It seems that I will have to drink a lot water during the day to keep up my training this summer.