The Strange, Mixed-Up Autumn - Winter - Spring of 2019-20

What can you say about the Winter of 2019-20 and  Spring of 2019; wacky! It came on gangbusters in November with the earliest and most snow in a storm ( heavy snowstorm on Veteran's Day).  While there have been a few earlier, heavy snowstorms (closest; Nov 15-16th,1932 with 9.0"; Nov 2-3 in 1966 with 6.0" and in 1951 with 5.6") but none up to November 11-12th have been as high as the 9.2" last autumn. Also; Flint tied for the 3rd biggest November winter storm with 9.0 inches of snow.  The biggest November storm for Flint dumped 13.4 inches on November 6-7, 1951. Saginaw's snowfall was much less at 4.0" on 11th and not nearly a potential candidate with 11.3" falling back on Nov 2-3, 1966.

Maybe not surprising; exceptionally cold November weather also occurred with the 13th coldest /35.8/ November on record at Detroit, 9th coldest /34.6/ at Flint and 4th coldest /33.3/ at Saginaw.

From the NWS - DTX More on the storm of Nov 11-12th

During the early morning period of November 11th, a surface low pressure began to develop over the Ohio Valley tied to a stationary boundary over that region.  Snow started to move into SE MI from the west shortly after 3am with the bulk of the region seeing snow falling by 4am. The initial part of the storm had 3 distinct heavier snow bands develop across our region that would begin to collapse together to form one distinct very heavy band by the noon/early afternoon time-frame. This band had 1" per hour snowfall rates over the western and northern Metro areas leading to the high totals seen across Washtenaw, Oakland, and Macomb counties. It would slowly move and pivot east across Detroit and the southern Metro area later in the afternoon as the low began to move east into Pennsylvania. While all this occurred, northerly flow off of Lake Huron allowed for lake-enhanced snowfall rates over the Thumb, especially over areas on the northern and eastern shorelines with some locations seeing over a foot of snow.

In spite of November's aggressive cold and snow introduction to the cold season; the Winter of 2019-20 ended up high on the list as a warmer than normal winter (see top 20 coldest/warmest summers rankings below). Detroit attained 9th warmest winter status since 1874 with a 32.6 degree average. Flint ranked even higher with 5th warmest winter with a 31.5 average and Saginaw made the warmest list at 7th place with a 29.8 average.

 

Winter Temps and Precipitation Maps

Temps

Precip

 

Snow Season 2019-20

Top 20 Coldest/Warmest Winters 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	18.8	1903-1904	36.9	1881-1882	16.7	1976-1977	33.4	1931-1932	15.7	1962-1963	33.3	1931-1932
2	19.3	1874-1875	35.7	1931-1932	17.0	1962-1963	33.0	2015-2016	16.5	1917-1918	31.7	2015-2016
3	19.7	1976-1977	35.2	1889-1890	17.8	1958-1959	32.2	1982-1983	16.6	1919-1920	30.9	1997-1998
4	19.7	1917-1918	33.8	2001-2002	18.6	1978-1979	31.7	2001-2002	17.5	1978-1979	30.6	2011-2012
5	20.4	1962-1963	33.8	1997-1998	19.0	2013-2014	31.5	2019-2020	18.0	1977-1978	30.5	2001-2002
6	20.6	1977-1978	33.5	2015-2016	19.3	1977-1978	31.3	1997-1998	18.2	1976-1977	30.0	1936-1937
7	20.8	1919-1920	33.0	2011-2012	19.8	1993-1994	31.2	2011-2012	18.2	2013-2014	29.8	2019-2020
8	20.9	2013-2014	32.9	2016-2017	19.9	1944-1945	30.3	1932-1933	18.2	1958-1959	29.6	1982-1983
9	21.0	1935-1936	32.6	2019-2020	20.9	1981-1982	30.2	2016-2017	18.7	1935-1936	29.5	1920-1921
10	21.1	1892-1893	32.5	1982-1983	21.2	1935-1936	29.1	1952-1953	19.0	1993-1994	29.4	2016-2017
11	21.4	1904-1905	32.5	1879-1880	21.3	1969-1970	28.8	1936-1937	19.2	1916-1917	29.0	1918-1919
12	21.5	1978-1979	32.3	1918-1919	21.4	1985-1986	28.6	1948-1949	20.0	1961-1962	28.8	1932-1933
13	21.7	1880-1881	32.2	1952-1953	21.5	1961-1962	28.5	2012-2013	20.1	1944-1945	28.5	2012-2013
14	21.8	1911-1912	31.6	1877-1878	21.6	2008-2009	28.3	1930-1931	20.2	1969-1970	28.3	1952-1953
15	21.8	1878-1879	31.3	1948-1949	21.6	1983-1984	28.2	1991-1992	20.3	1981-1982	28.0	1930-1931
16	21.9	1981-1982	31.2	1920-1921	21.6	1947-1948	28.2	1949-1950	20.7	1947-1948	27.8	1974-1975
17	22.4	1969-1970	31.1	1875-1876	22.0	2014-2015	28.1	1974-1975	21.2	2008-2009	27.6	1948-1949
18	23.0	1958-1959	31.0	1953-1954	22.2	2010-2011	28.0	1953-1954	21.3	2002-2003	27.2	1998-1999
19	23.2	1876-1877	30.8	1949-1950	22.4	1942-1943	27.8	1998-1999	21.4	1942-1943	27.1	1986-1987
20	23.3	2014-2015	30.7	2012-2013	22.5	2002-2003	27.7	1986-1987	21.6	1985-1986	27.1	1953-1954
* Detroit Area temperature records date back to November 1874. ** Flint Bishop temperature records date back to January 1921. *** Saginaw Area temperature records date back to January 1912.

 

 Winter 2019-20 Monthly Data

December 2019 
Winter took a holiday in December (the actual first winter month) with very mild temperatures and below to well below normal snowfall. December exchanged the Snowiest list to the Snowless list with Detroit 18th warmest with 35.1 degrees and 2.7" snowfall ( just missing 20th snowless at 2.6"). Keep in mind this was less than a degree colder than November's average of  35.8. More notable average temperature placements occurred further north with Flint placing 7th warmest December with 34.2 (as compared to November's 34.6)  and 7.0" of snow. Saginaw placed 12th warmest with 32.5 (compared to November's 33.3) and received 5.8" of snow.


January 2020  

January brought a mix of both mild January conditions yet normal to slightly above normal snow. Average temperatures ranged in the lower 30s; several degrees above the normals in the lower to mid 20s across Southeast Lower Michigan. Detroit's 32.4 degree average made it the 12th warmest January since records began with close to normal snow falling at 11.0". Flint's 32.0 average temperature placed it significantly further up the scale at the 4th warmest January on record. In addition; Flint's snowfall total of 16.8" pushed it into the January Snowiest List at 20th. Finally; the 30.4 degree reading at Saginaw  placed it at 5th warmest with normal snow at 11.0".


Jan 17-18, 2020 storm

Snow quickly moved in during the late evening on Friday, January 17, 2020 as a strong low pressure system moved in from the Midwest and across the Great Lakes region.   This strong system brought numerous advisories and warnings to the Midwest and Great Lakes.  The majority of the snow fell overnight and into the morning hours on Saturday before tapering off and transitioning to rain showers and drizzle over some parts of Southeast Michigan.  Snow, rain and sleet were all seen over the course of the later morning into early Saturday morning.  With the amount of moisture that was available with this system,  the characteristic of this snow was heavy and wet, making shoveling rather difficult.  During the heaviest snow, snowfall rates were 1+ inches per hour leading to many locations seeing 5 to 7 inches of total snow.

February 2020

Late winter remained generally mild yet with above normal snow. Temperatures averaged  30.1 at Detroit still 2.0 degrees above normal along with slightly above normal snow with 14.1". Flint averaged better than three degrees above normal in February with 28.0/+3.2 but with a hefty 18.8" of snow to boot creating the 12th snowiest February at Flint. Saginaw averaged 26.4 degrees with about normal snow at 10.7"


Feb 26th storm

A low pressure system formed out over the Southern Plains and moved northeast over the Ohio River Valley bringing snow to Southeast Michigan on February 26th.  This longer duration snow allowed for a Winter Weather Advisory to be issued, with the main bulk of the snow falling during the afternoon hours on Wednesday.  Snow continued to linger around through the overnight hours into early Thursday as the deformation zone (the northeast portion of the low pressure system) slowly pushed off to the east.  Snowfall totals averaged around two to six inches across much of the area.  Lesser snowfall totals were seen up in the Saginaw/Tri-Cities area, with higher amounts to the south. 

November Through March Cold Season

An example of the cold season can be seen with Detroit's average temperatures and departures from November 2019 through March 2020. As you can see it basically wasn't too cold with November through March averaging 34.9 degrees or 2.4 above normal. The sharply colder month of November belied the remainder of the season with every month after; notably above normal.

Detroit	Cold Season Nov - Mar   2019-20
	NOV	DEC	JAN	FEB	MAR	SEAS
Ave Temp	35.8	35.1	32.4	30.1	41.2	34.9
Depart	-5.7	5.0	6.8	2.0	4.0	2.4

Winter Analogues fail on projected warmth but perform on erratic expectations along with cold periods in the spring.

"Temperatures - Normal to Below"

"As with the majority of winters especially ENSO Neutral; look for temperatures during the 2019-2020 winter to be quite changeable under a fluctuating jet stream. The ongoing pattern recently experienced this fall was also telegraphed for the Winter for 2018-19. In fact; the similar cold and snowy weather experienced last November has even more aggressively repeated this November.

In my research; I’ve found Neutral ENSO patterns in the Pacific generally have little effect on the weather patterns in the Great lakes and Southeast Lower Michigan. This winter's analogues are strongly suggesting normal to below normal temperatures this winter with the clear majority pointing in that direction". 

There were two main problems with the guidance which lead to the analogues and subsequent Outlook. 


First and I feel most important; the upper polar low remained pretty much anchored most of the time up over the Arctic circle. This resulted in a very intense, at times near to record intense Polar Vortex contracted over the Arctic circle. This resulted in a +NAO/+AO which typically results in milder winter conditions for the Lakes as prevailing westerlies keep the door on the refrigerator mainly closed. 

Second; the ENSO neutral prediction failed to materialize until just recently in late spring into early summer. Therefore; strongly aided with the contracted Polar Vortex; the atmosphere continued to behave as though an El Nino was on-going through the winter. 

The two complimenting factors supported an unusually mild winter placing all three cities in the top 10 record warmest list (noted above in the Top 20 list).

An excellent write-up regarding the Bottled-up Winter 2019-20 Polar Vortex can be found here. The following discussion by Mark Vogan explains well the

"A record strong stratospheric polar vortex has brought probably the coldest Arctic winter in over a decade and so it should be of no surprise that Arctic sea ice cover has reached a 10-year high with the greatest coverage since 2010".

The cold/strong vortex has been mirrored from stratosphere down through the troposphere supporting a strong and persistent +AO/+NAO setup which hosts low pressure within the polar region and a strong zonal jet stream running west to east underneath. A strong zonal jet protects the mid-latitudes from polar air".

Come later spring; the Polar vortex "let loose" so to speak bringing record cold in May to the region (more on May 2020, below).

Spring 2020 Temps and Precipitation Maps

Spring 2020 

 

Why did is get so cold toward the end of spring?


Though the calendar said March (and the climate season announced spring); the weather fell into a more, strong warm/cold pattern with snow right into May.  As stated; the unusually deep and record cold Upper Low pressure hovered over the Polar region most of the winter. During the mid-late spring, the Polar Vortex began to disintegrate, break apart and drift south into the Northern Hemisphere especially into North America and Eurasia. This brought the usually cold pockets of air further south into the Great Lakes into the East and occasionally the South mid and especially later spring.

Ironically; March (and spring) actually began on a good note, only to be set back several weeks occasionally in April and especially the first half of early May. March's weather averaged notably above normal in temperatures and notably below in the snowfall. With Detroit's average temperature at 41.2/+4.0 and just 1.8" of snow of the March normal 6.9" brought hopes of an early, sustainable spring.

Unfortunately; the remnants of the Arctic air mass began to surge south into the Great Lakes during April into first half of May.  While April leaned toward the cooler side (basically averaging a degree or two below normal) a cool trend is not that uncommon in the Lakes early spring.

May started out warm enough but that was short-lived as most of early-mid May was a completely another story! Remnants of the Arctic air wrapped up in the weakening Polar Vortex over Canada pushed south into the northern U.S. Record breaking cold slammed the Lakes Region and ultimately engulfed a large portion of the country east of the Rockies by the second weekend.

Records were established with record lows at both Detroit and Flint. Detroit's record low of 27 on the 9th was not only a record for the date but the 3rd coldest May temperature ever recorded. The 27 degree reading is shared with another low of  27 on May 7th, 1974. The second coldest temperature in May occurred on May 1st, 1978 with 26. The coldest May temperature ever recorded in Detroit; 25 degrees back on May 10th, 1966.

The staying power of the abnormal May cold in Southeast Lower Michigan was no better represented than at Flint. Flint chalked up THREE CONSECUTIVE record lows for this May. A low of  29 on the 11th, 27 on the 12th and 25 on the 13th. The 27 and 25 degree lows were the coldest so late in May and season. The coldest temperature ever recorded in Flint occurred on the same day as Detroit's - with a 22 degree winter-like reading also on May 10th, 1966.

May 2020 Snow

Snow records were established in a few categories at Detroit; one for amount and the other for stretch of days with snow observed! First off; Detroit recorded a half inch /0.5"/ of snow on the 10th. That  0.5" of snow was the fourth latest day measurable snow was observed. The third latest was on May 13th 1912 with 1.5" and the second and first actually occurred in one snowstorm over two days. These two outstanding records for amount and lateness were; 2.3" of snow fell late on May 21st, 1883 with another 2.7" falling after midnight into the morning of May 22nd, 1883. The snowstorm total of 5.0" was the latest and highest amount of snow in a snow season! The latest snow has ever been observed in Detroit occurred way back on May 31st, 1910 with a trace.


Arguably; a record even harder to break was having snow recorded on several days in a May. That only occurred once, back in 1954 when four days had snowfall that is; until this May when FIVE consecutive snow days were observed May 8th - 12th!

A "heat-wave" of sorts later in the month erased much of cold snap negative monthly departures of 5 to 6 below normal to just a couple of degrees below to even above normal. Detroit's May average temperatures of 57.7 came in 2 degrees below normal (and actually colder than Flint's average; a rare bird indeed). Flint's temperature came in  above normal with 58.5 or 1.4 degrees above normal. Saginaw averaged slightly below normal with 58.5 or -0.9.

It was a generally wet spring with most areas seeing an inch or two above normal. 

Heavy rains brought scattered flooding across Southeast Lower Michigan in May. The most horrendous damage occurred in a damn failure on May 17-20th in Midland County along the Tittabawassee river after a heavy rain event.
(pics)


 




Brief Summer Outlook & Analogues will be out shortly.

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

 

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 month. 

                       Tornadoes, Snowstorms and Heat Waves - Oh May!

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 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	2019	5
6	0.0	2019	6
7	0.0	2019	7
8	0.0	2019	8
9	6.0	1923	9
10	0.5	1902	10
11	0.0	2019	11
12	0.0	2019	12
13	1.5	1912	13
14	0.0	2019	14
15	0.0	2019	15
16	0.0	2019	16
17	0.0	2019	17
18	0.0	2019	18
19	0.0	2019	19
20	0.0	2019	20
21	2.3	1883	21
22	2.7	1883	22
23	0.0	2019	23
24	0.0	2019	24
25	0.0	2019	25
26	0.0	2019	26
27	0.0	2019	27
28	0.0	2019	28
29	0.0	2019	29
30	0.0	2019	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	85/2018	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	91/2018	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 2018, 2015, 2013, 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.

Try to enjoy May's weather whatever it brings!   

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