Fertilizer Question

I'm not too experienced with fertilizing lawns. There's a fair bit of rain in the forecast but no real downpours. Just starting this Thursday and going to next Friday there are a 4 days, spread out a bit, forecasting 10 - 20mm of rain. They look like steady rains, not thunder showers. If I fertilize at the end of this week, is that too much rain in the system for it to be effective or should I be ok? I'm using Scotts Turf Builder.