Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.
Marginal VFR conditions (%)
Month
Average
2024
2023
2022
2021
2020
January
69.3
62
63
49
81
70
February
79.4
79
79
70
65
90
March
89.2
90
79
94
97
88
April
89.2
89
84
79
87
97
May
94.7
95
89
97
95
June
91.8
98
58
99
99
July
91.6
99
57
95
100
August
93.8
96
90
96
96
September
94.3
95
97
97
97
October
91.2
91
99
89
93
November
89.1
95
86
90
96
December
71.4
62
67
67
80
Average
87.2
81.0
87.6
78.5
89.8
92.7
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.
Maximum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-7.4
-6
-6
-8
-4
-7
February
-5.2
4
-5
-7
-10
-5
March
2.7
5
-2
3
8
4
April
10.0
14
8
7
12
10
May
20.4
24
20
21
18
June
26.8
28
28
29
27
July
27.4
27
29
29
28
August
25.5
27
27
27
26
September
21.9
24
23
24
20
October
12.2
13
15
17
9
November
3.0
6
1
6
7
December
-3.6
3
-5
-3
-1
Average
10.4
4.3
12.1
11.6
13.2
11.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-15.1
-12
-14
-21
-11
-15
February
-16.9
-6
-15
-20
-18
-15
March
-7.5
-5
-12
-7
-2
-5
April
0.1
3
-2
-1
1
0
May
8.7
11
8
8
8
June
15.8
18
15
16
16
July
16.6
15
17
18
17
August
15.8
17
17
16
17
September
11.6
14
12
12
10
October
2.8
5
4
7
0
November
-6.8
-4
-6
-4
-4
December
-11.1
-4
-12
-13
-10
Average
0.7
-6.7
2.3
0.9
2.7
1.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.5
19
18
2
12
17
February
10.2
10
4
12
6
7
March
6.7
14
13
2
2
1
April
9.1
15
9
15
9
5
May
3.2
2
2
1
4
June
1.7
1
0
2
1
July
2.4
1
2
1
2
August
2.4
2
0
2
2
September
2.7
1
0
5
1
October
3.7
2
1
5
7
November
6.9
7
12
2
1
December
12.8
20
20
13
9
Average
6.7
14.2
5.9
4.7
4.6
4.2
Precipitation during daylight period
Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.
Wind speed (knots)
Month
Average
2024
2023
2022
2021
2020
January
9.0
10
6
10
8
10
February
9.8
11
9
12
9
9
March
10.1
12
10
10
10
11
April
10.9
13
11
13
11
10
May
9.4
10
11
9
10
June
9.1
8
11
8
11
July
7.1
7
8
7
7
August
7.2
7
8
8
8
September
8.4
7
8
9
8
October
9.4
9
10
9
10
November
10.1
10
10
10
10
December
9.3
10
11
9
9
Average
9.4
11.7
8.6
10.0
8.9
9.3
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
288°
317°
314°
354°
244°
February
300°
127°
321°
260°
295°
March
344°
028°
342°
174°
213°
April
359°
349°
002°
345°
318°
May
139°
219°
204°
055°
June
119°
240°
238°
156°
July
312°
254°
166°
203°
August
174°
177°
194°
158°
September
141°
168°
211°
277°
October
302°
253°
159°
286°
November
278°
299°
273°
235°
December
281°
110°
272°
302°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.