Detroit Area Average Monthly Temperatures from 1870 to 1880
Year	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Avg for Year
1870											39.5	26.6
1871	25.4	26.0	39.8	48.9	60.1	67.3	70.5	71.0	59.0	54.0	33.3	22.9	48.2
1872	23.3	24.1	25.6	47.4	57.7	69.5	74.2	73.4	63.6	49.7	32.6	18.3	46.6
1873	20.4	22.4	30.9	43.1	56.9	70.7	72.2	70.8	61.3	48.1	32.5	32.7	46.8
1874	28.6	27.3	34.3	37.6	58.8	69.1	70.9	69.0	66.4	51.1	37.8	29.7	48.4
1875	15.3	12.3	28.0	40.5	56.7	66.0	69.6	66.8	59.9	46.5	34.5	32.8	44.1
1876	32.1	28.1	29.5	43.7	56.8	68.8	72.8	71.6	59.0	45.8	39.1	17.8	47.1
1877	19.2	33.6	26.0	45.4	56.4	66.1	72.0	71.2	64.3	53.8	39.2	38.1	48.8
1878	27.3	29.2	41.4	53.4	55.4	63.8	74.0	71.2	64.3	51.7	38.9	22.8	49.5
1879	20.8	22.0	34.3	45.2	59.1	65.1	72.8	69.4	58.6	59.6	38.1	28.7	47.8
1880	36.7	32.1	32.8	46.2	63.7	68.4	70.8	69.1	61.8	48.6	29.8	21.8	48.5

Last 50 or so year average:

UNITED STATES OF AMERICA - WEATHER AVERAGES

	ANNUAL	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP	OCT	NOV	DEC	YEARS	# CITIES
Average Temperature (F)	52.8	31.9	35.3	42.4	52	60.8	68.7	73.3	72.1	65.2	54.8	43.5	34.5	59	11,877
Average High Temperature (F)	62.9	42.2	46.3	53.8	64.3	73.2	81.1	85.7	84.4	77.4	66.7	53.8	44.8	56	12,609
Average Low Temperature (F)	49.4	33.7	35.7	42.1	49.5	57.9	64.9	68.8	67.8	62.4	50.1	41	35.7	60	185
Average Precipitation (in)	34.5	2.7	2.5	2.9	2.8	3.2	3.2	3.1	2.9	2.9	2.7	2.8	2.8	55	15,497
* Years is the average number of years used to compute the average. # Cities is the total number of locations used to compute the average.

Nope- sorry- not much different today than it was 100 years ago