With LawnCheck you can define a cycle that only runs if the current temperature or daily forecast temperature is higher than a value that you set (say 90 or 95 degrees). We call this a "Hot Weather Cycle."
What is the value of that? A "Hot Cycle" will automatically provide more irrigation to your landscape when temperatures become hotter than normal. This means you can adjust your main cycle minutes downward, because they don't have to account for unexpected hot weather that might harm a landscape.
Your landscape then receives only the amount of water it needs during cooler and normal weather and again, only the amount it needs during hot weather when the "hot cycle" kicks in.