With the above normal temperature we've had in and around the Big Easy the last month or so our grass has come out of dormancy a bit early. Along with that came an explosion of weed growth to include dollar weed and clover. Now I understand that some clover in one's yard helps to green it up with the nitrogen it imparts, but it's getting so thick it's a bear to cut.

So I decide to give Scotts 3 in one weed and feed (plus fireant killer a shot. I thought I has timed the application to be just before we were forecast to receive rain, a 90% + chance. That 90% chance has been reduced to 40% for this evening. If it does indeed rain I'm good, but what if it doesn't? The area that I applied it is FAR too large to water via hose. I could do around the house, but not the rest.

So... have I destroyed my lawn or might the relative low temps for today and tomorrow (mid 70's today, upper 70's tomorrow) give the rain time to come through before the grass is burnt?

You'll be fine. The types of Nitrogen in commercially available weed and feed is such that immediate water is less important.

You're OK on the temps but I've always found that treating broadleaf weeds separately works better and better with a topical solution.
YMMV

You're fine with rain tomorrow. Additionally, it's March not July so I wouldn't be worried about burning from a fast release fertilizer.

In Houston, we switch to a slow release fertilizer for summer. I'm assuming y'all do as well in New Orleans too.

Weeds! Fertilizer!

I just got in from 2.5 hrs of snow shoveling.

I shoveled snow, too.

Spring can't get here soon enough.

PC

Thanks y'all. It seems to have turned out just fine.