Historical weather data, all-time temperature records, and monthly climate averages for Brown Deer, WI. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in Brown Deer sits squarely in shoulder-season territory — expect a high around 48° and a low near 30°, with about a 1-in-4 chance of rain. The date has swung wildly in the past, from a balmy 75° in 1997 to a brutal 12° low in 1995, so don't put the layers away just yet.
Brown Deer's weather has real teeth on both ends — the thermometer has touched 104° in July 2012 and plunged to -40° in January 1982, a jaw-dropping 144-degree spread. On the wet side, a single August day in 2025 dropped 8.62 inches of rain, and a February storm in 2008 buried the area under 15.3 inches of snow.
Summer is the sweet spot, with highs peaking around 81–82° in mid-July, while mid-January is the dead of winter at a frigid 26° average high. If you're trying to dodge rain, note that late June is the wettest stretch of the year, averaging over an inch of precipitation in a single week.