XGY   Grimsby Mountain, ON
43-11-00  N    79-33-34  W
Normals :   1971-2000
Records :  1910-          
+ indicates most recent of multiple occurrences.
Note all stats on this page use  "climate days" rather than calendar days.  
             
 TEMPERATURE : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR
  Average Temperature : (°C)
 -5.5
 -4.9
 0.1
 6.3
 12.8 18.4
 21.4
 20.5
 15.6
 9.3
 3.7
 -2.6
 7.9
  Record Warm Month : 1.3
0.8
5.3
9.5
17.2
22.2
24.9
23.7
21.1
13.8
8.5
2.7
11.4
  Year : 1932
19982000
1998
1998 2005
1921+
2001
2002
1947
2001
2001
1998
  Record Cold Month : -11.7 -13.3
-5.9
2.7
8.5
14.8
18.5
17.4
12.9
5.4
-0.7
-7.3
5.5
  Year : 1918
19341960
1926
1917+
1928
1920
1927
1918
1925
1933
1917 1917
  Avg Maximum Temperature : -2.0
 -1.2 4.2
 11.1
 18.5
 23.9
 26.7
 25.5
 20.4
 13.4
 7.0
 0.8
 12.4
  Record High Temperature : 17.8
 18.0
 27.0
 30.6
 37.2
 36.1
 41.1
 40.6
 38.3
 30.4
 24.4
 21.0
 41.1
  Date : 25th
21st31st
26th
31st
3rd
9th
25th
3rd
8th
3rd
3rd
7/9
  Year : 1950
19971998
1957
1919
1934
1936
1948
1953
2007
1961
1982
1936
  Avg Minimum Temperature : -9.0
 -8.5
 -4.0
 1.5
 7.1
 12.8
 16.1
 15.5
 11.1
 5.1
 0.4
 -6.0
 3.5
  Record Low Temperature : -27.8 -29.4
 -22.8
 -17.2
 -4.4
 1.7
 5.6
 1.1
 -0.6
 -9.4
 -15.6
 -28.9
 -29.4
  Date : 25th
5th19th
1st
4th
3rd
15th
30th
30th
29th
16th
27th
2/5
  Year : 1945
19181916
1923
1935
1928
1930
1965
1935
1965
1933
1925 1918
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 RELATIVE HUMIDITY : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Average Rel Humidity : (%)
 74
 69
 72
 62
 68
 68
 68
 72
 77
 77 79 80 72
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 DEW POINT : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Average Dew Point : (°C)
 -9.4
 -9.6
 -4.3
 0.3
 7.0 12.3
 15.3
 15.3
 11.5
 5.5
 0.4
 -5.6
 3.2
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 PRECIPITATION : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Total Precip : (mm)
 71.9
 53.6
 62.6
 76.4
 76.3
 80.7
 77.1
 74.2
 93.5
 74.9 69.9 73.5 884.6
  Record Wet Month :
147.7
131.1
146.0
140.6
193.8
189.6
184.6
202.7
210.2
228.0
239.4
133.6
1164.6
  Year :
 1932
2008 1913
1996
1942
2000
1992
1956
1977
1954
1985
1990
1996
  Record Dry Month :
9.5
17.2
18.7
15.7
12.7
14.4
13.9
11.4
7.1
9.9
10.7
19.9
540.4
  Year :
 1961
1987
1915
1946
1920
1988
1918
1974
1960
1952
1930
1919
1941
  Record Precip in 1 Day :
 52.1
 40.6
 51.6
 41.9
 68.6
 78.0
 72.6
 90.2
 77.0
 115.3
 60.2
 61.0
115.3
  Date :
19th
16th
1st
20th
25th
11th
12th
29th
29th
15th
4th
12th
10/15
  Year :
1929
1954+
1972
1943
1953
1922
1962
1950
1924
1954
1985
1944
1954
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 RAINFALL : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Total Rainfall : (mm)
 29.3
 25.5 44.2
 68.2
 76.1
 80.7
 77.1
 74.2
 93.5
 74.7
 64.0
 43.3
750.8
  Record Rainiest Month : 130.9
100.0
144.2
131.1
193.8
189.6
184.6
202.7
210.2
228.0
230.0
127.4
1027.2
  Year :
 1932
1938
1976
1929
1942
2000
1992
1956
1977
1954
1985
1990
2006
  Record Least Rainfall : 0
0
4.3
14.5
12.7
14.4
13.9
11.4
7.1
9.9
10.7
0
447.5
  Year :
 1918+
1920+
1915
1946
1920
1988
1918
1974
1960
1952
1930+
1910
1941
  Record Rainfall in 1 Day : 52.1
 40.6
 51.6
 35.6
 68.6
 78.0
 72.6
 90.2
 77.0
 115.3
 60.2
 57.4
115.3
  Date :
19th
16th
1st
2nd
25th
11th
12th
29th
29th
15th
4th
21st
10/15
  Year :
1929
1954
1972
1917
1953
1922
1962
1950
1924
1954
1985
1949
1954


























  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 SNOWFALL : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Total Snowfall : (cm)
 49.6
 32.6
 18.0
 8.1
 0.2
 0
 0
 0
 0
 0.1
 6.0
 33.4
148.0
  Record Snowiest Month : 98.6
110.4
74.8
40.0
2.5
0
0
0
0
18.0
42.0
107.3
246.4
  Year :
 1939 1911
1916
1979
1923
+
+
+
+
1962
1933
1944
1940
  Record Least Snowfall : 3.0
0.4
0
0
0
0
0
0
0
0
0
3.8
54.7
  Year :
 1953 1998
1985
+
+
+
+
+
+
+
+
1950
1919
  Record Snowfall in 1 Day : 50.8
40.6
38.1
27.8
2.5
-
-
-
-
11.4
22.9
61.0
61.0
  Date  : 31st 15th
18th 6th
10th
-
-
-
-
24th
17th
12th
12/12
  Year : 1939 1911
1936
1994
1923
-
-
-
-
1962
1920
1944
1944
  Record Snow On Ground : -
-
 -
 -
 -
 -
-
-
-
-
 -
 -
 61
  Date  : -
 -
 -
 -
 -
 -
-
-
-
-
 -
 -
 12/12
  Year : -
 -
 -
 -
 -
 -
-
-
-
-
 -
 -
 1944
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR

 PRESSURE : Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
YEAR
  Average Pressure : (in)
 30.00
 30.04
 29.99
 29.98
 29.96
 29.96
 29.98
 30.02
 30.04
 30.05 30.02 30.03 30.01
  Jan
 Feb
 Mar
 Apr
 May
 Jun
 Jul
 Aug
 Sep
 Oct
 Nov
 Dec
 YEAR
Records from Grimsby 1910-13, Rock Chapel 1914-1966/04/17, Royal Oak 1966/04/18-1974, Grimsby 1975-1985/08/20,
     Rittenhouse 1985/08/21-1993/09/30, Vineland 1993/10/01-2003/09/17, and Grimsby Mountain 2003/09/18 to present.
Niagara Region
Records :1872-Present
* indicates Niagara Peninsula record
Temperature Record High
(°C)
  Location
 Date
 Year
Record Low
(°C)
  Location
 Date
 Year
  January : 22.2
  Niagara Falls
 		26th
 		1950
 		-32.8
  Welland
 25th
 1884
  February : 20.5
 Welland
 		26th
 		2000
 		-31.1
*-36.7
 Welland
 Caledonia
 		9th
9th
 		1934
1934
  March : 27.0
 Welland
 Vineland
 Vineland - Rittenhouse
** Fort Erie **
 		31st
31st
30th
*21st*
 		1998
1998
1998
*2012*
 		-27.8
  Welland
 4th
 1873
  April : 33.0
 Niagara Falls
 		28th
 		1990
 		-18.3
  Welland
 1st
 1923
  May : 37.2
 Grimsby - Rock Chapel
 31st
1919
-6.1
*-6.7 
 Welland
 Port Dover
 		6th
22nd
 		1932
1935
  June : 37.0
 Power Glen
 		8th
 		1984
 		0.0
*-1.7  
 St Catharines - CDA
 Port Dover
 		8th
9th
 		1949
1931
  July : 41.1
 Grimsby - Rock Chapel
 9th
1936
3.9
3.9
*3.3 
*3.3 
 Niagara Falls - Hydro
 Welland
 Port Dover
 Caledonia
 		11th
11th
12th
11th
 		1945
1945
1898
1945
  August : 40.6
 Grimsby - Rock Chapel
 		25th
 		1948
 		0.5
*-0.6    		 Welland
 Canborough 		29th
30th
 		1982
1965
  September : 38.3
 Grimsby - Rock Chapel
 3rd
1953
-2.2
*-3.9 
 Welland
 Hagersville
 		10th
23rd
 		1883
1974
  October : 32.8
 Niagara Falls
 5th
1951
-9.4
-9.4
 Smithville
 Grimsby - Rock Chapel
 		29th
29th
 		1965
1965
  November : 27.2
 St Catharines - CDA
 Vineland Station
 3rd
3rd
 		1961
1961
 		-20.0
 Welland
 26th
1880
  December : 22.0
*22.5 
 Port Dalhousie
 Hamilton - Lab
 		3rd
3rd
 		1982
1982
 		-27.8
*-29.4 
*-29.4 
 Welland
 Caledonia
 Port Dover
 		27th
20th
26th
 		1925
1942
1914
  YEAR : 41.1
 GRIMSBY - Rock Chapel 7/9
1936
-32.8
*-36.7 
 WELLAND
 CALEDONIA
 		1/25
2/9
 		1884
1934
  Record High
  Location
 Date
 Year
Record Low
  Location
 Date
 Year

 Precipitation Record Rain in
  1 Day (mm)
 Location
 Date
 Year
Record Snow in
  1 Day (cm)
 Location
 Date
 Year
  January : 52.8
*81.3 
Welland
Port Dover
 		7th
21st
 		1998
1959
 		78.7
 Welland
 22nd
 1902
  February : 82.8
Niagara Falls
 16th
1954
61.0
 Welland
 12th
 1894
  March : 51.6
Grimsby Rock Chapel
 1st
1972
81.3
 Welland
 1st
 1900
  April : 51.1
*88.4 
Niagara Falls
Port Dover
 		29th
26th
 		1921
1937
 		43.2
 Welland
 11th
 1894
  May : 68.6
Grimsby Rock Chapel
 		25th
1953
14.8
 Fort Erie
 7th
 1989
  June : 108.7
Port Colborne
 25th
1968
0
 -
 -
 -
  July : 141.0
Welland
 3rd
1892
0
 -
 -
 -
  August : 107.7
*115.6 
Grimsby
Hamilton PH
 		28th
8th
 		1950
1981
 		0
 -
 -
 -
  September : 118.4
Welland
 		30th
 		1959
 		TR
(ice pellets)
Ridgeville
 23rd
1989
  October : 122.7
Grimsby
 15th
1954 20.3
*24.6 
Welland
Hamilton PH
 		31st
25th
 		1873
1962
  November : 78.2
*86.4 
Port Colborne
Port Dover
 		4th
7th
 		1985
1951
 		58.4
Fort Erie
 14th
1974
  December : 71.9
Niagara Falls
 29th
1954
66.0
Vineland Station
 11th
1944
  YEAR : 141.0
WELLAND
 		7/3
 		1892
 		81.3
WELLAND
 3/1
1900
  Record Rain
in 1 Day
 Location
 Date
 Year
Record Snow
in 1 Day
 Location
 Date
 Year

 Precipitation Record
Snow Depth (cm)
 Location
 Date
 Year
 


  January : 70
 Thorold
 15th 1999



  February : 62
*64 
Ridgeville
Hamilton A
 		29th
7th
 		1984
1978



  March : 61
Balls Falls
 1st 1984


  April : 30
Niagara Falls
 1st
1987


  May : 9
Niagara Falls
 7th
1989


  June : 0
-
 -
-


  July : 0
-
 -
-


  August : 0
-
 -
-


  September : 0
-
 -
-

  October : TR
*2 
-
Hamilton A
 		-
21st
 		-
1989



  November : 44
Fort Erie
 22nd
2000



  December : 82
Fort Erie
 28th
2001

  YEAR : 82
FORT ERIE 12/28
2001

  Record
Snow Depth
 Location
 Date
 Year


Snow Depth data incomplete..currently being researched.
 Wind Record
Sustained
Dir
 Location
 Date
 Year
 Record Gust
 Dir
 Location
 Date
 Year
  January : 48
*48 
89
89
 SW
SW
 Niagara District A
Hamilton A
 		-
-
 		-
-
 		74
 137
 S
 Niagara District A
 26th 1978
  February : 50
 93
 NW Grass Island  -
 -
 59
*66 
109
122
 230
SW
 Port Colborne LS
Hamilton A
 		4th
27th
 		2003
1997
  March : 56 104
 230
 Port Colborne LS
 		9th
 		2002
 		73
 135
 230
 Port Colborne LS
 		9th
 		2002
  April : 50
 93
 SW
 Port Colborne LS -
 -
 74
 137
 SW
 Niagara District A
 3rd
 1982
  May : 40
 74
 SW
 Port Colborne LS -
 -
 52
*57 
96
105
 SW
SW
 Niagara District A
Hamilton A
 		10th
16th
 		1990
1973
  June : 35
*37 
65
69
 SW
SW
 Niagara District A
Hamilton A
 		-
-
 		-
-
 		62
 115
 SW
 Niagara District A
 12th
 1978
  July : 34
 63
 SW
 Niagara District A -
 -
 58
 107
 S
 Niagara District A
 5th
 1991
  August : 37
 69
 SW
 Port Colborne LS -
 -
 55
 102
 W
 Niagara District A
 1st
 1995
  September : 42
 77
 SW
 Port Colborne LS
 		-
-
 		-
-
 		72
 133
 W
 Niagara District A
 2nd
 1980
  October : 49 91
 230
 Port Colborne LS 25th
 		2001
 		67
 124
 230
 Port Colborne LS
 		25th
 		2001
  November : 54
 100
 250
 Port Colborne LS
 13th
 2003
 67 124
 250
 Port Colborne LS
 		13th
 		2003
  December : 56
 104
 230
 Port Colborne LS 12th
 2000
 69 128
 230
 Port Colborne LS
 		12th
 		2000
  YEAR : 56
 104
 230
 PORT COLBORNE LS
 3/9
 2002
+
 74
 137
 SW
 NIAGARA DISTRICT A
 4/3
 1982+
  Record
Sustained
 Dir
 Location
 Date
 Year
 Record Gust
(kt - km/h)
 Dir
 Location
 Date
 Year
Wind data incomplete..currently being researched.
Grimsby Mountain normals computed as follows..
1) Double-mass analysis between Grimsby and Rock Chapel for avbl concurrent data 1914-66. Grimsby Mountain temp differences/pcpn ratios interpolated from this data for elevation.
2) Double-mass analysis between Grimsby, Hamilton A, and Niagara District A for avbl concurrent data 1970-85. Grimsby 1971-2000 normals derived from Hamilton A + Niagara District A 1971-2000 normals using this analysis.
3) Grimsby Mountain differences/ratios applied to Grimsby 1971-2000 normals.
4) Hamilton A normal liquid-to-snow ratios applied to Grimsby Mountain pcpn totals to account for Grimsby C.S. using standard 10:1 ratio instead of actual measurements of water equivalent.
5) April & May normal snowfalls calculated manually to account for sparse data producing unacceptable analomies..