Planning for the weather is an important factor for making your trip to Deerfield Beach a success, especially when you're splurging. The hottest months are usually August and July, with an average temperature of 28°C, while the coldest months are January and February, with an average of 22°C. The rainiest months in Deerfield Beach are September, June, August and July, with each month seeing an average of 238 mm of rainfall.