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
81.4
74
64
84
97
75
February
89.6
72
93
92
95
97
March
89.8
85
94
91
93
92
April
94.2
89
94
99
93
May
96.5
93
97
97
96
June
96.3
93
99
99
94
July
95.6
95
93
91
99
August
94.9
91
97
97
99
September
93.6
88
97
99
99
October
94.0
90
98
93
95
November
80.8
87
76
88
70
December
89.9
94
85
91
94
Average
90.5
77.3
89.4
92.6
95.0
92.4
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
-9.5
-11
-8
-10
-5
-9
February
-10.9
-3
-8
-9
-14
-5
March
-1.2
-3
-6
-1
5
-1
April
9.4
8
8
13
7
May
20.2
24
19
19
19
June
24.3
27
23
27
22
July
27.2
26
28
31
26
August
26.2
27
29
26
27
September
20.6
23
25
23
21
October
10.8
10
15
13
8
November
-2.7
4
-4
2
-1
December
-7.5
1
-13
-12
-4
Average
7.6
-6.2
10.6
9.8
10.7
9.0
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
-18.3
-19
-16
-21
-15
-18
February
-20.5
-13
-18
-20
-24
-17
March
-12.2
-14
-17
-11
-7
-12
April
-4.2
-4
-3
-3
-6
May
4.7
8
4
3
4
June
10.4
13
9
11
10
July
12.6
11
13
14
13
August
10.8
11
13
12
11
September
6.2
8
8
6
6
October
-2.1
-1
1
-1
-4
November
-10.3
-6
-12
-9
-10
December
-16.1
-9
-22
-21
-14
Average
-5.6
-16.7
-2.4
-3.2
-3.3
-4.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
22.0
25
14
30
21
23
February
22.5
25
17
22
18
13
March
15.7
20
14
24
11
15
April
10.0
14
18
5
9
May
5.7
6
7
7
6
June
7.4
2
13
4
13
July
4.8
4
7
2
7
August
4.9
9
7
8
2
September
6.4
4
3
3
4
October
8.7
17
3
5
5
November
20.9
4
33
9
25
December
15.4
3
29
20
19
Average
12.5
23.1
8.6
14.9
8.5
10.8
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
9.1
9
8
10
10
9
February
9.3
9
10
10
10
9
March
10.4
10
9
11
10
10
April
11.3
11
13
11
11
May
10.3
9
11
10
11
June
9.9
9
9
10
11
July
9.2
8
9
9
10
August
8.8
9
9
9
10
September
9.8
9
11
11
11
October
10.2
10
10
10
11
November
9.8
10
11
9
10
December
8.8
9
10
9
9
Average
9.7
9.4
9.2
10.3
9.9
10.2
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
293°
272°
294°
237°
268°
February
284°
231°
264°
270°
242°
March
020°
122°
304°
227°
317°
April
093°
044°
315°
293°
May
094°
352°
193°
182°
June
189°
011°
273°
332°
July
313°
318°
294°
242°
August
288°
264°
272°
258°
September
191°
232°
254°
285°
October
254°
274°
166°
281°
November
249°
304°
221°
265°
December
232°
312°
249°
240°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.