After suffering through the chilliest April in more than 40 years May reversed course and ranked among the ten warmest, ranking sixth (4.5 degrees above average). The month's unseasonable warmth began right out of the gate as May 1 saw a high of 80° followed by back-to-back days with highs in the 90s. This was one of the warmest beginnings to May on record (see chart below). There were also three days later in the month with highs of 88° (5/17), 89° (5/26) and 89° (5/29). The last time May had five days with highs of 88° or hotter was in 1991 (which was the warmest May on record).
After the three previous months each had more than five inches of precipitation, May was drier than average, with 3.55" of rain measured. However, there was a period in which seven days out of eight had rain (May 12-19); this included a severe thunderstorm on 5/15 that moved through during the evening rush hour (five people in the metropolitan area were killed by falling tree limbs).
Twelve days had highs of 80° or warmer, eight days were 10 degrees or more above average and three days had lows in the 70s. And although May 2 and 3 had highs in the 90s, the most uncomfortable day was May 26, which had a heat index of 93° (its high was 89°). By contrast, May 2 and 3 had very low humidity and their "feels like" temperatures were lower than the air temperature. Only six other Mays have had three or more lows in the 70s (since 1930), with two of them being in 2016 and 2015.
Balancing the two days in the 90s were two days with highs in the 50s - May 13 (Mother's Day) had a high of 54° and May 19 had a high of 56°.
Last May was just 3.9 degrees warmer than April, the second closet the two months have been (closest was 3.5 degrees in 1945). By contrast, this May was 17.4 degrees warmer than April, the seventh furthest from April (furthest was 18.1 degrees in 1944). May is typically 9.3 degrees warmer than April.