No chance of getting bored in Wyoming if you like the outdoors. Summer brings highs in the 80's to Emigrant Trail. Summer night lows plunge down to the 70's. The cold days of the wintertime come with highs in the 80's, and during the dark hours in the wintertime at Emigrant Trail temperatures plunge to the 70's. Emigrant Trail usually gets a good deal of rain. September is the month that gets the most rain, and the driest of the months is May.