Not a problem that we tend to have here in the UK.... the heat I mean! Some patches do stick more securely than others. I have found Evorel patches stick well and where you you put them also makes a difference, away from any clothes seams or edges that might catch. I find the best place for me is below the top of my pants, away from the seam towards the back. I put my palm over the patch for 2 minutes to warm it so it adheres better. I now find it difficult to peel them off. Whether this would still be effective in the conditions you have to contend with I don't know, but I did struggle to keep other patches on at first, even with UK temperatures. As my prescriptions merely states estradiol patches, rather than a make, I have had the chance to try several makes and some stick better than others.