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
78.4
63
78
96
77
67
February
89.2
92
91
98
84
97
March
84.7
93
84
94
84
77
April
92.0
92
96
93
92
93
May
88.4
91
89
90
86
June
96.0
100
97
95
98
July
96.0
95
94
96
99
August
95.4
94
97
99
98
September
92.7
96
97
95
90
October
89.0
91
100
88
91
November
93.4
99
97
97
91
December
84.2
75
70
91
86
Average
89.8
85.6
90.9
94.2
90.8
89.7
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
0.5
-3
1
2
2
1
February
3.7
11
5
5
-4
5
March
11.0
14
9
11
14
12
April
17.2
19
19
17
17
17
May
23.0
26
23
22
20
June
29.7
30
30
31
31
July
29.7
29
31
29
30
August
28.7
30
31
29
30
September
26.4
28
25
27
25
October
17.4
18
20
19
15
November
10.2
12
9
12
13
December
4.5
6
2
8
4
Average
16.0
10.0
17.6
17.7
17.2
16.9
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
-8.4
-10
-6
-11
-5
-7
February
-7.1
-2
-6
-9
-12
-5
March
-1.9
1
-3
-2
3
2
April
4.4
7
4
4
4
3
May
12.2
13
13
12
11
June
18.2
18
18
19
19
July
19.6
18
20
19
20
August
17.9
18
18
19
18
September
14.8
15
12
15
13
October
6.2
8
6
8
4
November
-1.5
1
-2
1
1
December
-5.7
-2
-6
-3
-5
Average
5.3
-2.8
6.5
5.4
6.8
6.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.0
11
6
3
12
7
February
5.6
1
4
3
11
1
March
7.6
5
7
7
7
7
April
4.8
4
4
4
4
4
May
6.5
2
8
7
14
June
2.9
2
2
2
1
July
3.8
7
3
1
2
August
4.7
3
5
1
1
September
3.3
3
2
2
5
October
6.9
5
2
5
3
November
4.3
4
6
3
4
December
7.7
13
13
1
6
Average
5.3
5.0
4.8
4.6
4.4
4.5
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
7
8
9
9
9
February
9.8
10
10
11
8
10
March
11.1
11
11
12
12
10
April
11.6
13
13
13
11
11
May
9.3
8
11
9
9
June
8.5
6
9
8
10
July
6.6
5
8
7
7
August
6.8
7
7
7
8
September
8.2
8
8
8
9
October
9.0
9
9
8
9
November
10.1
9
12
10
10
December
8.9
7
10
10
8
Average
9.2
10.5
8.3
9.9
8.7
9.2
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
302°
314°
261°
315°
283°
February
257°
260°
303°
324°
286°
March
346°
327°
330°
150°
190°
April
287°
253°
233°
285°
297°
May
138°
174°
146°
359°
June
143°
185°
174°
165°
July
148°
194°
157°
149°
August
185°
169°
155°
175°
September
169°
149°
172°
222°
October
287°
241°
266°
295°
November
214°
258°
237°
223°
December
283°
217°
243°
301°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.