Looking at all of the months of every year since the reporting of weather conditions began in Central Park in 1869, the temperature that has the distinction of occurring the most times as a month's coldest reading is 52° in June, which has occurred in 25 years (most recently in 2016), or about once every six years. And the daily high that's most frequently been the hottest of any month is 94° in July as well as in August; it's been the hottest reading in those two months 22 times (most recently in 2017 and 2021, respectively).
Looking across months, the temperature that has had the most designations as hottest reading of a month is 92°, which has had that distinction 76 times across six months. (Second most is 94°, which has been hottest 72 times across five months.)
By contrast, the daily low temperature with the most designations as coolest is 57°, which has been the coolest reading 45 times across four months. Second most is 41 times for the lows of 17° and 52°, occurring in five months and four months, respectively.
Here are the greatest concentrations by month:
August - 80% of its hottest readings have been between 89°-96° (an 8-degree range)
June - 75% of its hottest readings have been between 89°-96° (an 8-degree range)
June - 75% of its coolest readings have been between 49°-55° (a 7-degree range)
May - 73% of its coolest readings have been between 40°-46° (a 7-degree range), and 50% have been between 41°-44° (just a 4-degree range)
- February and March have had the most different temperatures that have been coldest (both with 30) or warmest (both with 34), while June has had the fewest (15 and 19), with July having practically the same amount (16 and 19) .
- The most frequent chilliest temperature in July, 60° (22 times), last happened in 1995, which is the longest current hiatus of any month for a temperature that has been coldest or warmest. But despite this lengthy hiatus, it's still comfortably ahead of 58° and 59°, which have both happened 19 times. Looking at warmest reading, the last time February's most frequent mildest reading occurred (58°) was in 2005.
- For five years in a row (1989-1993), September's chilliest reading was 44°. In five of the six years between 1946-1951 the hottest temperature in July was 94° (the outlier was 102° in 1949). Also in July, five of the six years between 1973-78 had 58° as the coolest reading; the outlier was a low of 59° in 1974.
- Half of the 16 occurrences of the low of 13°, which is the most frequent coldest low temperature in December, were concentrated in the 15 years between 1886-1900. The other eight 13° readings occurred in the course of the other 137 years.
- Despite it being April's most frequent coldest low, there was a 31-year period between 1874-1904 when the low of 33° wasn't the coldest reading. And the low of 42° in May (tied for the month's second most frequent low) had a hiatus of 36 years between 1893-1928.