The 2 largest cities in Idaho are Boise with a population of  145,987 and Nampa with 81,557. The next 3 largest cities are  Meridian with 75,092, Idaho Falls with 56,813 and â¦ Pocatello with  54,255.
Averages for Washington DC in September. The weather in September in Washington DC is very attractive for those that want to avoid the peak heat of summer, yet still enjoy lots of warm days on their visit. On average, peak temperatures during the day in September still reach up to 27Â°C.
So, how is the weather in Washington DC in October? Early in the month you can expect warm temperatures during the daytime to reach the low to mid 70s f (about 23C) and occasionally into the 80s f (about 29C) while early morning lows are mostly in the mid-50s f (about 13C).