This post was inspired by the first four days of December 2019, all which reported highs and lows in the 30s. The last time there was a streak of this length was in January 1998, when there was one of five days. Although days "stuck in the 30s" aren't rare, as a typical year sees a half dozen of them, strings of three days or longer happen infrequently, about once very five years. Not surprisingly, nine out of ten of these days have occurred from December thru March, with December having the most. (They've occurred as early as Oct. 26 and as late as April 11).
More than half of these days have reported measurable precipitation (57% to be exact); one in four have reported measurable snow. Since many of these days have temperatures around freezing (two-thirds have a reading of 32° or colder for at least part of the day) the type of precipitation that falls is a mixed bag (i.e., rain, freezing rain, sleet, and wet snow). Often the type of snow that falls doesn't readily accumulate on paved surfaces if the temperature is above freezing. And although temperatures in the 30s are far from frigid, the fact that they're often accompanied by overcast skies or precipitation makes these days feel raw and colder than the air temperature.
The most precipitation to fall on one of these "stuck" days was 2.03" on March 29, 1984 (high/low of 36°/34°); 1.8" of the precipitation was snow. Additionally, there have been four other storms that produced two+ inches of liquid precipitation that crossed over to other days - in Jan. 1987, March 1967, Dec. 1930 and Dec. 1914 (all days were in the 30s). The biggest of them all produced 3.49" of precipitation and lasted three days during the first week of March 1967; two inches of snow fell on the first day of the storm.
Speaking of snow, the most to fall on a day with temperatures in the 30s for its entirety was ten inches on Feb. 10, 2010 (high/low was 34°/30°). And 11.8" fell from a storm that crossed over into a second day on March 21-22, 1956. In addition to these snowfalls, there have been nine others that dropped six to ten inches (most recently on March 21, 2018 when 8.2" fell on a day in which the high/low was 39°/31°).
In the years since 1900, the longest streak of days stuck in the 30s is five, which has happened three times: in Jan. 1998, Dec. 1970 and in Dec. 1914. The most days in one winter was 20, which occurred in the winter of 1997-98. Every winter except one, 1924, has had two or more days stuck in the 30s. (The winter of 1924 had one day.) Finally, the most in one month is eight, which has happened twice - in January 1987 and January 1998. (December 2019 had seven.)
If this analysis leaves you cold, I also posted one last year about days stuck in the 70s.