Our weather year in review: 2021
By Brad Spakowitz
Now that 2021 is officially in the history books, we can take a look back at how Brown County fared through the year. weather-wise.
Here’s the bottom line: The year as a whole was warmer and drier than average.
The mean average temperature was 2.1 degrees above the 30-year average, making 2021 the sixth warmest on record, with records dating back to 1886.
Precipitation (rain, melted snow and ice) totaled 29.56 inches, 2.05 inches less than average, a welcome break from three back-to-back very wet years (2018-20).
Here are the 2021 highlights, month-by-month.
January – much warmer, drier
January was much like the final month of 2020 – much warmer and drier than average.
The month was a whopping 6.4 degrees above average, with temperatures only dropping below zero two times.
Only 5.5 inches of snow fell all month, less than half the average amount (14.3 inches).
Total precipitation (rain, melted snow and ice) measured .75 inches, which is .38 inches less than average.
February – much colder, slightly drier
February was not as dry, measuring a total of 1.06 inches of precipitation, just .05 inches less than average.
A closer look reveals generous snowfall, 13.5 inches, roughly half of which fell in a single day (Feb. 4, 6.7 inches).
An outbreak of prolonged icy-cold weather followed, lasting nearly two weeks.
We had 12 consecutive nights with temperatures dropping below zero, many of which were in the negative double digits.
The coldest, negative 16 (Feb. 11), was also the coldest temperature recorded during the entire year.
Another big temperature swing arrived the final week of the month, with six days in the 40s, but not enough to skew the overall monthly average, still coming in at a very cold -5.8 degrees below “normal.”
March – much warmer and drier
March brought an early feeling of spring, with many days unusually warm for the third month of the year.
Thirteen days had high temperatures at or above 50 degrees, with three of those in the 60s.
By month’s end, temperatures averaged 5.6 degrees above the norm.
Given the warmth, it is not surprising measurable snowfall was sparse, falling only four times, totaling 3.7 inches, about half the average amount (8.1 inches).
Total precipitation for the month came in at 1.32 inches, a deficit of .64 inches.
April – warmer, much drier
Early April brought incredible warmth, with highs in the 70s for three consecutive days (Apr. 5-7) – the warmest was 79 degrees on April 6.
There were eight other days in the 60s, helping boost the monthly average to 2.9 degrees above “normal.”
Total precipitation for the month was 1.69 inches, which is 1.31 inches below average.
The final measurable snow of the season fell April 21, bringing the 2020-21 seasonal snowfall (October through April) total to only 33.7 inches, making it the 18th least snowy season on record.
May – slightly warmer, much drier
May brought teases of summer with 14 days recording high temperatures of 70 degrees or more, six of those in the 80s.
The last reading of 32 degrees was on the morning of May 12.
The average monthly temperature ended up at just .3 degrees above the 30-year average.
May received 2.16 inches of rain, which is 1.19 inches less than average.
If you are keeping count, that is five dry months in a row – six, if you include December 2020.
However, one big problem ensued – numerous grass and brush fires.
On a brighter note, by then, water levels on Lake Michigan had dropped by about 2 feet, helping diminish the threat of flooding.
June – much warmer, wetter
June continued the trend of unusual warmth, with 19 days in the 80s, seven of which were in the 90s – the longest stretch of heat so early in the season.
By month’s end, temperatures came in 4.7 degrees above average.
June brought the dry trend to an end with a total of 4.72 inches of rain, .62 inches above average, and marked the beginning of what turned out to be a wet summer.
July – slightly cooler, wetter
July rainfall was somewhat sporadic, though totaled 4.42 inches, .8 inches above average.
Temperatures were mostly seasonal, but just a few cool-for-July days skewed the monthly average by minus .1 degree – the first of only two months all year where the average monthly temperature was colder than the 30-year average.
A line of thunderstorms moved across the state on the evening of July 28 into the early morning hours of July 29, produced 17 tornadoes and damaging winds – most of it to our south.
August – warmer, much wetter
August was a warm, humid month with temperatures average 2.5 degrees above normal, but the big weather news was soaking rains and storms.
A prolonged stretch of stormy weather (Aug. 7-11) brought 4.98 inches of rain over the period, along with three tornados: An EF1 (Aug.10) near Nichols (Outagamie County); And two EF0 tornados the following day (Aug. 11), one near Angelica (Shawano County), another near Pulaski (Brown County).
After a mid-month dry spell, more rounds of rain came late in the month, bringing the monthly total to an incredible 8.30 inches, 4.91 inches above average.
September – warmer, much drier
Taking an abrupt turn from summer, the first month of fall was very dry with only 1.17 inches of rain falling, 2.03 inches less than average.
The morning of Sept. 7 brought a line of severe storms that produced unusually large hail, with one hailstone near Appleton measuring 4.5 inches in diameter, tying for the third largest hail ever reported in the state.
Monthly temperatures averaged 1.7 degrees above average.
October – much warmer and drier
It was arguably the nicest October in recent memory, with ample sun and unusual warmth through the first three weeks of the month, delaying the changing of fall color.
The monthly average temperature came in at 6.6 degrees above normal, making it the fifth warmest October on record.
It was also the second dry month in a row, measuring only 1.15 inches of rain, 1.52 inches less than average.
November – slightly colder, much drier
In true November fashion, the weather went downhill quickly, with 2-4 inches of snow falling by mid-month (Nov. 14), and more in the second half of the month.
The monthly total snowfall measured 6.4 inches, just shy of two times the average amount (3.3 inches).
Total precipitation (rain, melted snow and ice) was a mere .81 inches, 1.17 inches less than average, making it the fourth driest November on record.
Temperatures averaged .4 degrees colder than average, making it one of only two months all year long that was colder than average.
December – Much warmer, slightly wetter
Despite temperatures being 3.7 degrees above “normal,” December brought a bit more snow than typical, 15 inches total.
The month’s melted snow and ice plus rain equaled 2.01 inches, .26 inches above average.
It was an active month, with a powerful storm mid-month bringing all-time record warmth for December, along with damaging winds here, and eight tornadoes in southwestern Wisconsin, the latest ever on record in the state.
Other 2021 climate stats
• Ten days at or above 90 degrees, roughly two times the average, 95 the warmest (June 5).
• Thunderstorms reported on 40 days.
• Total snow: 43 inches, 12.6 less than average.
• Greatest peak wind: 61 mph, July 26.