How much does temperature effect your sweat rate?

I have started measuring my sweat rate by weighing before/after rides and tracking fluid consumed. So far it seems to be in the 0.8 to 1.0 L/hr range for 2 hour cooler outdoor rides.

It's been mostly in cooler weather ( below 75F / 24C). I expect this rate might almost double when the weather gets above 90F / 32C.

For those that have measured, how much variation have you seen?

Approaching 2 L/hr there is no way to replace that on the bike. Last year I got wrecked a couple of times from dehydration in the peak of summer and am trying to protect this season if I can.