Tornadoes, Snowstorms and Heat Waves - Oh May!

While March is generally considered one of the most volatile months in Southeast Lower Michigan weather-wise, May doesn't pull any punches either! You would think that by May; spring's extreme weather in these parts would settle down some - don't bet on it. Scanning over a century's worth of weather records show some interesting and quite variable weather conditions during the upcoming month.

Tornadoes! 

One of the strongest and earliest documented tornadoes in Southeast Lower Michigan occurred in May, 1896! While details are sketchy, evidently a massive tornado plowed across Oakland and Lapeer Counties during the early evening hours on May 25th sometime between 7 PM to 9 PM. The tornado leveled numerous homes in the towns of Ortonville, Oakwood and Thomas ( both no longer exist). In fact, parts of these homes were found 12 miles away! At least 47 people were killed, including nine people from one house alone, along with approximately 100 injured as a result of this vicious storm which has been estimated as an EF-5 (wind speeds greater than 200 mph). Later that evening (likely closer to 9 PM), another tornado was seen in Sanilac County which possibly was from the same parent of super-cell thunderstorms. It's also interesting to note that May of 1896 turned out to be the fourth warmest May (see May Top 20 records chart at the end of this write-up) in recorded history at Detroit, perhaps the unseasonably warm weather helped fuel the severe weather. I was interviewed by the Oakland Press years back in 2009 about this terrible tornado. Also, included in the article are pictures of the now defunct town Oakwood before and after.

Some of the strongest tornadoes to hit Southeast Lower Michigan occurred in the early to mid 1950's. The most noteworthy was the monster Flint/Beecher tornado that occurred in 1953 also an EF-5, but that storm hit in the month of June (8th). (An in‑depth article I wrote on the tornado can be found here). Unfortunately, Genesee County was hit again just three years later on May 12th, 1956 with another devastating tornado (EF4 on the enhanced fujita scale with a wind of 166‑200 mph). After the Flint/Beecher storm, this is the second strongest tornado to hit Genesse County. Like its predecessor, this storm also formed in the Flint vicinity (3 miles east of Flint) but then tracked southeast to 3 miles northwest of Atlas rather than east. This tornado killed 3 people and injured 116 while taking out more than 100 homes and five commercial buildings along its path. The average width of the storm was about 300 feet and it is the last killer tornado to hit Genesse County.

Just less than a month before the massive Flint/Beecher tornado in June 8th, on May 21st,1953 the first of two EF4's (166-200 mph) tornadoes ever to hit St. Clair county tore a mean path through the south side of Port Huron. By all accounts, the south side of Port Huron was devastated by this twister. There were two deaths and 68 injuries along with an estimated 90 homes destroyed and another 300 damaged as the tornado ripped through the region. Also, along with the loss of homes, an additional 83 buildings were destroyed and another 124 buildings damaged. As a severe thunderstorm moved northeast across St. Clair county, the tornado was spawned just southwest of Port Huron over the town of Smith's Creek. The tornado then took aim on the south side of Port Huron, reaching nearly a mile wide across at its worst as it tore through the area on its way into Canada.

*The second EF4 tornado to hit St. Clair county also occurred in May...May 8th, 1964...the Anchor Bay Tornado. The tornado actually developed over Macomb County, 3 miles north of Mt. Clemens, then plowed east northeast across New Baltimore to just north of Algonac, in extreme southern  St. Clair County, before crossing the St. Clair River into Canada. This tornado killed 11 people and injured more than 200 as it destroyed 132 homes and damaged another 240 homes and farms.

But this tornado wasn't the most damaging in St. Clair County. That distinction belongs to an EF3 (136‑165 mph) tornado that hit St. Clair and Macomb Counties also in May...May 2nd, 1983. The tornado was again spawned over Macomb County, this time over the extreme southeast portion of the county near Eastpointe. The storm then blew across Lake St. Clair and into Harsens Island and damaged or demolished 25 to 30 homes, an aircraft hangar and a large building. The estimated cost of the damage was over $5 million.

Snow-OH !

 

While a few snow flurries or snow showers are all not that rare in Southeast Lower Michigan in the month of May, the following two snowstorms were and both I wrote in-depth about; here!

One storm occurred May 21st‑22nd, 1883, while the other, the more documented of the two, hit the area May 9th, 1923. The snowstorm on May 9th, 1923 was probably the most severe and extensive over Southeast Lower Michigan of the two ( I wrote in‑depth article on this storm very early in my Weather Historian career. 1996 titled "Snowstorm of May 9th, 1923").  Records at Detroit show a six‑inch snowfall by the evening of the 9th, while further north and west of the city it was even worse! Six to nine inches fell across the Ann Arbor area north into Howell and east, across Pontiac and Port Huron. Even more incredible, snow depths flirting with a foot were observed from Lansing and Flint area, north into the Saginaw Valley and Thumb Region. Widespread damage occurred when such a heavy wet snow fell on top of the newly sprouted spring vegetation. Afternoon and evening temperatures hovered in the lower to mid 30s, while a bitter cold (particularly for May) northwest wind blew at 15 to 25 mph.

The May 21st‑22nd, 1883 snowstorm by the date alone sounds almost unbelievable! Very little was written in the archaic Detroit weather records about the storm at the time. In fact, the snowstorm was not confirmed until much later (1904), since officially continuous snowfall records did not start until 1885. The following is from the official observation form...

                                                         May 21, 1883

            Rain began at 900am. Snow from 250pm to 910pm. Hail 934am to

           1005am and 110pm. Strong wind reaching 36 mph from the North.

           Temp from 32.5  to 46.0. Baro rising.

        

                                                         May 22, 1883

           Hail ended during the night. Snow began during the night. Rain and

           snow  ended 1005am. Northerly wind reaching 28 miles. Temp from 

           32.5 to 41.0  Snowfall estimated by Inspector Conger to have been

           5.0 in ‑ on 21st&22nd    (This entry made April 28, 1904 ‑ CDC.J)

The snowfall was split between the two days and recorded as 2.3 inches on the 21st and 2.7 inches on the 22nd. While hail was a likelihood, especially in the afternoon on the 21st as the colder air moved in, I suspect the hail recorded overnight into the 22nd could have well been graupel or sleet. One may also wonder with such cold air advected into the region at the surface and aloft in late May,  if thundersnow (sleet/hail) didn't also occur somewhere over Southeast Lower Michigan, especially with accumulating snow. The snowfall recorded on the 21st & 22nd in 1883 is by far the latest measurable snowfall recorded in Metro Detroit. The next closest, heaviest measurable snowfall date‑wise is 1.5 inches, which fell on May 13th, 1912 and then, our other big storm with the total of six inches on May 9th, 1923. The latest snow was officially observed in Detroit was the last day of May...May 31st, 1910 when a trace fell. By the way, it's interesting to note that not one of the pre-mentioned Mays with measurable snowfall placed in the top 10 coldest Mays in Detroit.

May Daily Snowfall Records

Date	Snowfall (Inches)	Year	Date
1	0.3	1909	1
2	0.1	1909	2
3	0.1	2005	3
4	0.2	1907	4
5	0.0	2015	5
6	0.0	2015	6
7	0.0	2015	7
8	0.0	2015	8
9	6.0	1923	9
10	0.5	1902	10
11	0.0	2015	11
12	0.0	2015	12
13	1.5	1912	13
14	0.0	2015	14
15	0.0	2015	15
16	0.0	2015	16
17	0.0	2015	17
18	0.0	2015	18
19	0.0	2015	19
20	0.0	2015	20
21	2.3	1883	21
22	2.7	1883	22
23	0.0	2015	23
24	0.0	2015	24
25	0.0	2015	25
26	0.0	2015	26
27	0.0	2015	27
28	0.0	2015	28
29	0.0	2015	29
30	0.0	2015	30
31	T	1910	31

Heatwaves

Now, from one extreme to another, lets look at Heat Waves. While there have been hot days in May with records into the 90s, there are only two years that had extended periods of hot weather in May and those are 1962 and 1977. The hottest and more consecutive of the two was in 1962 when from May 14th‑May 18th, the daily high temperature climbed to ninety or above. This hot spell created five new consecutive record high temperatures which still stand to this day. In 1977, there were also five new record highs established but they were not consecutive, nor all in the 90s up until 2007 & 2012 when two were superseded (see: Tables, below). Very recently (in climate terms) May of 2012 was a very warm month and had its share of records also.

May - Detroit Records 1874 - Present

May Normals (1980-2010)				Maximum		Minimum		Average Daily Temperature		Precipitation
Date	Max	Min	Avg	Record High	Lowest Max	Highest Min	Record Low	Highest	Lowest	Greatest	Date
1	65	45	55.0	86/1942	40/1909	70/1942	26/1978	78/1942	35/1909	1.46/1875	1
2	66	45	55.0	85/2012	39/1940	64/1942	29/1978	73/1942	34/1875	1.66/1892	2
3	66	45	56.0	89/2012	40/1929	64/1955	28/1978	76/1955	38/1957	1.31/1997	3
4	66	46	56.0	89/1949	45/1954	66/1955	28/1966	77/1955	39/1954	1.05/1990	4
5	67	46	56.0	90/1895	42/1917	70/1949	29/1891	80/1949	38/1917	0.85/1991	5
6	67	46	56.0	90/1949	46/1935	66/1941	31/1974	74/2000	40/1974	1.75/1976	6
7	67	46	57.0	86/2000	40/1947	68/1964	27/1974	77/2000	36/1947	0.97/1948	7
8	67	47	57.0	87/2015	38/1947	68/2000	30/1976	77/2000	34/1947	0.85/1974	8
9	68	47	57.0	90/1896	39/1923	68/1965	29/1983	79/1896	35/1923	2.12/1875	9
10	68	47	58.0	90/1936	42/1902	67/1896	25/1966	78/1896	38/1966	2.33/1948	10
11	68	48	58.0	87/1993	43/1960	67/1881	30/1907	76/1896	39/1907	1.91/1914	11
12	69	48	58.0	90/1881	44/1966	65/1881	32/1934	78/1881	39/1895	1.48/2002	12
13	69	48	59.0	89/1977	45/1888	66/1956	30/2013	77/1991	41/1910	1.48/1991	13
14	69	49	59.0	91/1962	40/1895	66/1962	34/1984	79/1962	39/1895	1.39/1916	14
15	70	49	59.0	92/1962	48/1945	71/1962	33/1973	82/1962	42/1895	1.46/1923	15
16	70	49	60.0	92/1962	47/1945	70/1962	32/1984	81/1962	44/1957	1.09/1945	16
17	70	50	60.0	93/1962	48/1916	67/1962	31/1973	80/1962	43/1973	1.22/1980	17
18	71	50	60.0	93/1962	48/1915	70/1962	32/1973	82/1962	43/2002	1.50/2000	18
19	71	50	61.0	91/1934	40/1894	69/1996	32/2002	80/1996	37/1894	1.68/1949	19
20	71	51	61.0	91/1977	48/2002	68/1934	33/1981	79/1934	42/1895	1.56/1959	20
21	71	51	61.0	92/1977	46/1917	71/2013	32/1883	80/1934	39/1883	1.69/2004	21
22	72	51	62.0	90/1994	41/1883	67/1941	32/1883	78/1941	36/1883	1.14/1949	22
23	72	52	62.0	89/1964	46/1917	71/1964	34/1935	80/1964	40/1917	1.69/2004	23
24	72	52	62.0	87/2007	44/1925	67/1991	33/1925	77/1933	39/1925	1.26/1950	24
25	73	52	62.0	90/2012	47/1979	70/2012	35/1992	80/2012	45/1979	1.67/2011	25
26	73	53	63.0	92/1944	47/1961	70/1991	36/1983	79/1914	43/1961	2.56/1968	26
27	73	53	63.0	91/1941	51/1906	71/1941	35/1915	81/1941	46/1915	1.68/2014	27
28	74	53	64.0	95/2012	52/1930	72/1941	35/1907	82/1941	46/1894	2.02/1935	28
29	74	54	64.0	92/2006	48/1889	70/2006	32/1966	81/2006	42/1889	1.65/1876	29
30	74	54	64.0	93/1942	44/1889	73/1929	36/1966	81/1929	40/1889	2.27/1889	30
31	75	55	65.0	95/1895	46/1910	71/1919	34/1910	83/1895	26/1898	1.98/1946	31
Normal High: 69.9				Normal HDD: Month: 208				Normal Monthly Precip: 3.38
Normal Low : 49.4				Normal HDD Season: 6092				Normal Yearly Precip: 12.54
Normal Mean: 59.7				Normal CDD: Month: 42				Ave Snow this Month : -1.0
				Normal CDD Season: 48				Ave Snow for the Season: 42.7
Precip: Greatest Monthly Total: 8.46/2004							Snow: Greatest Monthly Total: 6.0/1923
Precip: Least Monthly Total: 0.43/1920							Snow: Least Monthly Total: 0.0/na

                            1962                                                                     1977

DATE.............RECORD HIGH..........................DATE..............RECORD HIGH

5/14                         91                                        5/13                          89   

5/15                         92                                        5/20                          91

5/16                         92                                        5/21                          92

5/17                         93                                        5/24                          87/equaled & superseded 2007/

5/18                         93                                        5/25                          89 /superseded by 90 2012/

        

Both Mays placed in the top ten hottest Mays in Detroit with 1962 placing 5th and 1977 placing 8th with recent editions of 2015, 2012, 1998 & 1991. Ironically; May of 1991 placed at the top of the list for the warmest May but ironically, not one record high temperature was set that month.

Top 20 Coldest/Warmest Mays in Southeast Lower Michigan
Rank	Detroit Area*				Flint Bishop**				Saginaw Area***
	Coldest		Warmest		Coldest		Warmest		Coldest		Warmest
	Temp	Year	Temp	Year	Temp	Year	Temp	Year	Temp	Year	Temp	Year
1	51.1	1907	66.5	1991	48.7	1997	65.0	1982	49.8	1924	64.6	1977
2	51.3	1917	65.5	1998	50.0	1966	65.0	1936	49.9	1945	64.0	1998
3	51.8	1967	65.3	2012	50.6	1967	64.7	1934	50.0	1917	63.4	1975
4	51.9	1966	65.3	1896	50.6	1945	64.4	1922	50.2	1997	63.2	1991
5	52.0	1997	65.2	1962	51.5	1984	64.2	1991	51.3	1947	62.8	1936
6	52.1	1924	64.7	1911	51.9	1947	62.9	2015	51.6	1967	62.7	1934
7	52.5	1945	64.5	2015	52.5	1961	62.9	2012	51.6	1915	62.5	1982
8	52.6	1935	64.4	1977	52.6	1973	62.9	1998	51.8	1925	62.5	1922
9	52.7	1882	64.3	1881	52.7	1954	62.7	1987	51.9	2002	62.2	2012
10	53.1	1915	64.2	1982	52.9	1968	62.6	1977	51.9	1983	61.6	2015
11	53.8	1947	63.7	1964	52.9	1924	61.9	2013	51.9	1954	61.5	2013
12	53.9	1910	63.7	1880	53.1	2002	61.9	1939	52.1	1966	61.5	1962
13	54.2	1883	63.6	2013	53.4	2005	61.8	1975	52.5	1946	61.3	2010
14	54.3	1888	63.3	1987	53.5	1983	61.6	1965	52.7	1935	61.1	1964
15	54.4	1983	63.3	1944	53.8	1974	61.5	1962	52.8	1948	61.1	1959
16	54.5	1984	63.1	1965	53.8	1948	61.4	1944	53.0	1974	61.0	1985
17	54.5	2002	63.0	1887	54.0	1957	61.1	1933	53.1	1956	60.7	1965
18	54.5	1890	62.8	1975	54.1	1963	61.1	1921	53.4	1957	60.5	1988
19	54.7	1954	62.8	1936	54.1	1935	60.9	1959	53.4	1923	60.4	1987
20	54.7	1925	62.8	1922	54.1	1925	60.9	1941	53.6	2003	60.4	1941
* Detroit Area temperature records date back to January 1874. ** Flint Bishop temperature records date back to January 1921. *** Saginaw Area temperature records date back to January 1912.

Well; all we can do is hope the month of May warms up - and dries out some - and is a great month for outdoor late spring activities and gardeners!

Making weather fun while we all learn,
Bill Deedler -SEMI_WeatherHistorian