Historic Halloween Weather

1981-2010 Halloween Averages
High: 61
Low: 41
Mean: 51
Precipitation: 0.09″
Snowfall: 0.0″

Top 20 Warmest Halloween Highs
1. 1950: 83
2. 1974: 80
3. 1900: 79
4. 1927, 1933: 78
5. 1979, 2003: 75
6. 1882, 1901, 1982, 1999: 74
7. 1909, 1990: 73
8. 1888, 1935, 1944, 1987: 72
9. 1915, 1971: 71
10. 1919: 70
11. 1891, 1986, 2001, 2008: 69
12. 1929, 1956, 1978, 1981, 1985, 2005, 2007: 68
13. 1903, 1943, 1946, 1952, 1991, 2013: 67
14. 1902, 1916, 1953, 1965, 1984: 66
15. 1942, 1958, 1961, 1968, 1969, 2009: 65
16. 1896, 1897, 1912, 1921, 1922, 1940, 1945, 1964, 1997, 2004: 64
17. 1914, 1941, 1970, 2000, 2006: 63
18. 1886, 1924, 1934, 1959, 1977, 1983, 1998: 62
19. 1892, 1938, 1989, 1995: 61
20. 1963, 1966, 1994: 60

Top 20 Coldest Halloween Highs
1. 1906: 38
2. 1993: 39
4. 1878, 1895: 40
5. 1913, 1923, 1954: 41
6. 1885, 1917, 2012: 42
7. 1890: 43
8. 1908, 1925, 1926: 44
9. 1898, 1905: 45
10. 1930, 1976: 46
11. 1879, 1931, 2002: 47
12. 1894, 1918, 1939: 48
13. 1955, 1962, 1996, 2014: 49
14. 1880, 1972: 50
15. 1973, 2010, 2011: 52
16. 1907, 1951, 1988: 53
17. 1887, 1893, 1932, 2015: 54
18. 1883, 1928, 1949, 1975: 55
19. 1899, 1967: 56
20. 1884, 1911, 1937, 1957, 1980, 1992: 57

Top 20 Warmest Halloween Lows
1. 1919: 61
2. 1882: 60
3. 2003: 59
4. 1927, 1929: 58
5. 1900, 1956, 2013: 57
6. 1921, 1941, 1982: 56
7. 1950: 55
8. 1959, 1979: 54
9. 1971: 53
10. 1881, 1891, 1933, 1946, 1974, 1991: 52
11. 1901, 1984, 1998: 51
12. 1947: 50
13. 1961, 2001: 49
14. 1935, 1948, 1960, 1967, 1985, 1995, 1999: 48
15. 1889, 1896, 1909, 1943, 1977: 47
16. 1924, 1945, 2004, 2016: 46
17. 1899, 1911, 1916: 45
18. 1903, 1940, 2015: 44
19. 1965, 1970, 1973, 1981, 1989, 1990, 1992, 1997, 2009: 43
20. 1888, 1942, 1957, 1994, 2006: 42

Top 20 Coldest Halloween Lows
1. 1887: 20
2. 1962, 1988: 25
3. 1923: 27
4. 1908, 1925: 28
5. 1885, 1893, 1913, 1917, 1953, 1975: 29
6. 1904, 1906: 30
7. 1878, 1938, 1954, 1968: 31
8. 1928, 1934, 1949, 1958, 1964, 1976, 1980, 2000: 32
9. 1879, 1926, 1930: 33
10. 1890, 1936, 1951, 1966, 1969, 1993, 1996, 2002, 2008, 2010: 34
11. 1892, 1920: 35
12. 1894, 1895, 1932, 1955, 1978: 36
13. 1910, 1983: 37
14. 1886, 1898, 1914, 1939, 1944, 1963, 2007, 2012, 2014: 38
15. 1884, 1905, 1918, 1937, 2005, 2011: 39
16. 1880, 1883, 1907, 1952, 1972, 1986, 1987: 40
17. 1897, 1902, 1912, 1915, 1922, 1931: 41
18. 1888, 1942, 1957, 1994, 2006: 42
19. 1965, 1970, 1973, 1981, 1989, 1990, 1992, 1997, 2009: 43
20. 1903, 1940, 2015: 44

Top 20 Wettest Halloweens
1. 1932: 1.44″
2. 2009: 1.21″
3. 2013: 0.98″
4. 1941: 0.97″
5. 1919: 0.91″
6. 1942: 0.51″
7. 1960: 0.45″
8. 1905, 1973: 0.43″
9. 2006: 0.36″
10. 1989: 0.34″
11. 1976: 0.32″
12. 1993: 0.31″
13. 1972: 0.29″
14. 1994: 0.26″
15. 1895: 0.23″
16. 1959: 0.20″
17. 1948: 0.18″
18. 1889: 0.17″
19. 1921, 1951: 0.15″
20. 1963, 1967, 2012, 2014: 0.11″

Snowiest Halloweens
1. 1993: 1.0″
2. 1954: 0.2″
3. 1906, 1917, 1926, 1930, 1951, 2012: Trace

Greatest Snow Depth
1. 1954: Trace

Fall Weather Correlation to Winter Severity?

As we go into the winter season, it’s time to talk about how this one might end up. There’s a belief that fall weather is a good sign of how cold or warm winter will be. How true is that for Columbus? Also, what might any correlation mean for the winter of 2017-2018?

First, let’s just look at October temperatures.
The October normal mean temperature for Columbus is 55 degrees.

Between 1878 and 2016, there have been 47 Octobers that featured a mean temperature of 53.9 degrees or lower, what we’re considering a Cold October for the purposes of this comparison.
Of those 47 Octobers, 27 of the 47 had following winters that were colder than normal, or 57.4%, 13 had average temperature winters, or 27.7%, and the remaining 7 were warmer than normal, or 14.9%.
Interestingly, this category contains both the warmest winter on record- 1889-1890 and the coldest on record- 1976-1977- as shown by the chart below.

Next, we look at Normal Octobers, which are +/- 1 degree of the 1981-2010 Average of 55 degrees.
Between 1878 and 2016, there were 45 normal Octobers. Of those, 21 had colder than normal following winters, or 46.7%. 11 were followed by normal winters, or 24.4%, and 13 had warmer than normal winters, or 28.9%.

Finally, let’s look at warm Octobers, which are those with means of 56.1 degrees or higher. There were 46 Octobers with warmer than normal means since 1878. Of those, 18 featured following winters that were colder than normal, or 39.1%. Another 18, or 39.1%, were followed by average winters. The final 10 winters were warmer than normal. Here’s the graph.

So just based on the October mean temperature, Octobers that are colder than normal have a 47% higher chance of having a colder than normal winter than warmer than normal Octobers do. But is October a better indicator than November, a month that is closer to actual winter?

Colder than normal Novembers- 43.3 degrees or lower- included 78 Novembers since 1878. Of those, 38 or 48.7% had colder than normal winters. 21 (26.9%) had normal winters and 19 (24.4) had warmer than normal winters.

With the 38 normal Novembers, 43.4 to 45.4 degrees, there were 18 that had colder than normal winters, or 47.4%, with 11 normal winters (28.9%) and 9 warmer than normal winters (23.7%).

Finally, there were 24 warmer than normal Novembers since 1878- 45.5 degrees or higher. Only 6, or 25%, were followed by cold winters. An additional 9 (37.5%) were normal, while the last 9 (37.5%) were warmer than normal.

To reiterate, here are the ranked percentages of cold winters by the preceding October or November.
1. Cold Octobers: 57.4%
2. Cold Novembers: 48.7%
3. Normal Novembers: 47.4%
4. Normal Octobers: 46.7%
5. Warm Octobers: 39.1%
6. Warm Novembers: 25.0%

It should be no surprise that cold Octobers and Novembers have a stronger correlation to the following winters also being colder, with colder winters becoming increasingly unlikely as those months warm. Cold Octobers have a higher correlation than Cold Novembers, as well as Warm Octobers, but Normal Novembers have a slight advantage over Normal Octobers. Based on this, October actually has a stronger correlation to the following winter’s temperature mean than does November.

Going further, though, what about bi-monthly combinations?

Rank of Bi-Monthly Combinations and the percentage of colder than normal following winters, along with total years in sample:
Normal October/Normal November: 87.5% 8 Years
Cold October/Warm November: 57.1% 7 Years
Cold October/Cold November: 53.8% 26 Years
Normal October/Cold November: 48.1% 27 Years
Warm October/Cold November: 44.0% 25 Years
Cold October/Normal November: 38.5% 13 Years
Warm October/Warm November: 28.6% 7 Years
Warm October/Normal November: 26.7% 15 Years
Normal October/Warm November: 0.0% 8 Years

So a normal fall is clearly the best, but the sample size is not particularly high. Normal to Warm is unanimously warm, but again, it has a small sample size.

October 2017 has been overwhelmingly warm. While this wouldn’t normally bode well for a cold winter, each year is influenced by a multitude of factors.

Thanksgiving Day Historic Weather and Climatology

*Reposted from 2013, updated through 2015.

Normals *1981-2010
High: 48
Low: 33
Mean: 40.5
Precipitation: 0.11″
Snowfall: 0.1″

Top 10 Coldest Highs
1. 1930: 12
2. 1936: 26
3. 1880, 1903, 1905: 27
4. 1938: 28
5. 1892, 1898: 29
6. 1881: 30
7. 1945, 2002, 2013: 32
8. 1886, 1889, 1890, 1929, 1958: 33
9. 1882, 1885, 1901, 2014: 34
10. 1912, 1947, 1956, 1982, 2000: 35

Top 10 Coldest Lows
1. 1930: 3
2. 1930, 2005: 15
3. 1929, 1984: 16
4. 2000: 17
5. 1880, 1881, 1892, 1894, 1958: 18
6. 1901, 1905, 2002: 19
7. 1898, 1936, 1938, 1950, 1982, 1989, 1996: 20
8. 1911, 1956, 2013: 21
9. 1882, 1886, 1912, 1945: 22
10. 1994, 2008: 23

Top 10 Warmest Highs
1. 1896: 70
2. 2015: 65
3. 1915, 1940: 64
4. 1879, 1908, 1981, 2007, 2012: 63
5. 1966, 1968, 1973, 1979: 62
6. 1918, 1941: 61
7. 1914, 1927, 1983: 60
8. 1933: 59
9. 1899, 1957: 58
10. 1921, 1943, 1990, 2010: 57

Top 10 Warmest Lows
1. 1979: 53
2. 1896: 52
3. 1940: 51
4. 1957: 49
5. 1879: 48
6. 1934, 1966, 2015: 47
7. 1968: 46
8. 1913, 1933, 1978, 1990, 2003: 43
9. 1899, 1927, 1961: 42
10. 1908, 1951, 1987, 1991, 1998: 41

Top 10 Wettest
1. 2010: 1.76″
2. 1961: 1.58″
3. 1968: 1.22″
4. 1990: 0.71″
5. 1921, 1925: 0.70″
6. 1926: 0.69″
7. 1980: 0.65″
8. 1887: 0.60″
9. 1957: 0.59″
10. 1951: 0.49″

Top 10 Snowiest
1. 1880: 3.2″
2. 1950: 1.1″
3. 1938: 0.8″
4. 1959: 0.7″
5. 1889: 0.4″
6. 1945, 1957: 0.3″
7. 1890, 1954, 2005: 0.2″
8. 1953, 2004: 0.1″
9. Multiple: Trace
10. Multiple: 0


Most Snow on the Ground

1959: 1″
2013: 1″
Trace: Multiple

Summer 2016

Now that Summer 2016 is but a memory, let’s take a quick look back at where it stands in the record books.

Temperature

Summer 2016 Means
June-August Mean High: 85.5
June-August Mean Rank since 1878: 26th Warmest
While the average high for Summer 2016 was certainly warm, it fell just outside of the top 25. By comparison to recent years, 2010 (85.6), 2011 (85.7) and 2012 (87.7) all had warmer average highs.

June-August Mean Low: 66.1
June-August Mean Low Rank since 1878: 4th Warmest
The average low for the summer is what made 2016 much more exceptional. No recent years (last decade) were warmer, although 2010 did tie.

June-August Mean: 75.8
June-August Mean Rank since 1878: 10th
So if you thought this summer was hot, well you were right. Only 2010 (75.9) and 2012 (76.4) were warmer of any recent years.

Monthly Means
June Mean: 73.2
June Mean Rank since 1878: 17th Warmest
July Mean: 76.6
July Mean Rank since 1878: 20th Warmest
August Mean: 77.6
August Mean Rank since 1878: 6th Warmest
The summer gradually became hotter as it went on.

Summer 2016 Misc. Temperature Stats
# of 90+ Days: 18
90+ Days Rank: 22nd
Warmest High: 95
Warmest Low: 77
Coldest High: 72
Coldest Low: 48

Daily Temperature Records
June 11th: Record Warm Maximum Tie: 95: Tied with 1914 and 1933.
August 10th: Record Warm Minimum Tie: 75: Tied with 2001.
August 11th: Record Warm Minimum Tie: 76: Tied with 1918.
August 12th: Record Warm Minimum: 76: Beat record from 1947.
August 13th: Record Warm Minimum Tie: 75: Tied with 1995.

Precipitation

June-July Precipitation Total: 13.53″
June-July Precipitation Rank since 1878: 29th Wettest
Besides being warm, Summer 2016 was also fairly wet.

Monthly Precipitation Stats
June Precipitation: 5.22″
June Precipitation Rank since 1878: 29th
July Precipitation: 2.49″
July Precipitation Rank since 1878: 27th Driest
August Precipitation: 5.82″
August Precipitation Rank since 1878: 13th Wettest
So the summer was bookended by wet months with July being fairly dry.

Summer 2016 Misc. Precipitation Stats
Total Precipitation Days (including Trace): 45
Total Measurable Precipitation Days: 30
Measurable Precipitation Days Rank since 1878: 16th Highest
Days with 0.25″ or Higher: 16
Days with 0.50″ or Higher: 10
Days with 1.00″ or Higher: 4

Daily Precipitation Records
June 23rd: 2.75″: Beat the old record in 1901.

Historic Record of Early Season Cold

With temperatures predicted to fall to near freezing for the first time this week for the fall season, I thought it might be interesting to take a look at the incidence of early-season cold, and the average on when it tends to arrive.

Here are the earliest dates on record for the following:

Temperatures Below 40 and Temperature Range of Observed Dates
1. 8/29/1965: 39
2. 9/8/1951: 39
3. 9/9/1883: 39
4. 9/13/1964: 38
5. 9/14/1902, 9/14/1923, 9/14/1953, 19/14/1975: 38-39
6. 9/17/1959: 37
7. 9/20/1896, 9/20/1956, 9/20/1962: 37-39
8. 9/21/1889, 9/21/1897, 9/21/1991: 37-38
9. 9/22/1918, 9/22/1974, 9/22/1976, 9/22/1995: 37-38
10. 9/23/1885, 9/23/1913, 9/23/1963, 9/23/1967, 9/23/1981, 9/23/1989: 35-39

Average Date of First Under-40 Temp By Decade (1878-2014)
2010s: October 11th
2000s: October 8th
1990s: October 2nd
1980s: September 30th
1970s: October 1st
1960s: September 25th
1950s: September 25th
1940s: September 30th
1930s: October 11th
1920s: October 2nd
1910s: October 9th
1900s: October 5th
1890s: October 1st
1880s: October 2nd
1870s: October 1st

Highs Below 32
1. 10/30/1917: 32
2. 11/3/1951, 11/3/1966: 28-29
3. 11/4/1991: 27
4. 11/6/1967: 31
5. 11/7/1971: 31
6. 11/8/1976: 32
7. 11/10/1913: 27
8. 11/12/1920, 11/12/1921, 11/12/1932: 30-32
9. 11/13/1911, 11/13/1919, 11/13/1986, 11/13/1996: 25-32
10. 11/15/1880, 11/15/1893, 11/15/1916, 11/15/1933, 11/15/1940, 11/15/1969: 24-32

Average Date of First 32 or Below High By Decade
2010s: December 4th
2000s: December 2nd
1990s: December 7th
1980s: November 28th
1970s: November 29th
1960s: November 23rd
1950s: November 26th
1940s: December 2nd
1930s: November 27th
1920s: November 28th
1910s: November 22nd
1900s: November 30th
1890s: November 25th
1880s: November 30th
1870s: December 4th

Lows Below 32
1. 9/21/1962: 31
2. 9/29/1961: 32
3. 9/30/1888, 9/30/163: 31-32
4. 10/1/1899: 30
5. 10/2/1886, 10/2/1908, 10/2/1974: 31-32
6. 10/3/1975, 10/3/1981, 10/3/2003: 32
7. 10/4/1952, 10/4/1987: 29-32
8. 10/5/1965, 10/5/1968: 31-32
9. 10/6/1892, 10/6/1964, 10/6/1980, 10/6/1988: 30-31
10. 10/7/1889, 10/7/1935: 30-31

Average Date of First 32 or Below Low By Decade
2010s: October 24th
2000s: October 26th
1990s: October 22nd
1980s: October 17th
1970s: October 17th
1960s: October 8th
1950s: October 22nd
1940s: November 3rd
1930s: October 24th
1920s: October 28th
1910s: October 31st
1900s: October 24th
1890s: October 20th
1880s: October 20th
1870s: October 26th