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
82.9
82
66
88
92
84
February
89.7
83
92
92
88
91
March
87.1
88
93
81
95
94
April
92.8
95
95
99
96
May
94.9
94
97
95
91
June
94.6
90
97
99
89
July
92.7
90
98
88
94
August
96.2
96
100
93
99
September
95.2
96
100
96
98
October
95.6
92
100
96
98
November
87.7
91
84
94
84
December
88.9
100
85
86
85
Average
91.0
84.5
90.8
93.4
93.7
92.2
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
-6.3
-12
-3
-7
-3
-10
February
-7.1
-3
-6
-5
-11
-1
March
1.0
0
-2
3
7
-1
April
8.9
9
7
13
7
May
18.8
22
16
17
17
June
21.7
23
20
25
20
July
23.8
23
25
26
23
August
23.3
24
25
25
23
September
18.2
19
20
20
19
October
9.8
10
14
12
7
November
0.3
3
-3
4
0
December
-5.3
0
-11
-11
-1
Average
7.2
-5.0
10.9
9.2
10.3
8.6
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
-14.0
-19
-9
-14
-11
-18
February
-16.4
-10
-14
-12
-20
-12
March
-10.8
-10
-11
-5
-6
-11
April
-3.7
1
-3
-3
-4
May
6.0
11
6
4
5
June
10.7
14
11
12
9
July
12.5
14
15
13
12
August
11.3
15
14
11
11
September
6.6
8
8
6
7
October
-1.1
1
3
-1
-3
November
-8.1
-4
-10
-7
-8
December
-13.4
-6
-19
-19
-9
Average
-3.3
-13.4
2.3
0.1
-2.4
-2.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.4
30
17
22
10
9
February
12.8
19
20
18
10
10
March
10.1
20
13
23
3
10
April
6.0
5
14
0
7
May
5.2
3
12
0
9
June
8.9
13
18
2
14
July
6.1
11
7
1
12
August
4.4
12
7
3
4
September
3.2
3
0
2
3
October
4.6
16
1
1
9
November
10.7
3
25
5
9
December
6.3
0
19
7
4
Average
9.8
22.5
10.2
14.0
3.0
8.4
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
6.5
7
6
5
7
6
February
6.8
7
8
5
7
7
March
6.9
7
7
5
7
8
April
7.7
8
5
8
9
May
7.6
8
4
8
8
June
6.9
8
4
7
6
July
6.0
8
3
7
6
August
6.2
7
3
7
7
September
6.6
8
4
7
7
October
7.6
9
5
7
7
November
6.6
6
8
7
7
December
6.6
5
6
6
6
Average
6.8
7.0
7.5
4.6
6.9
7.1
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
267°
293°
319°
260°
268°
February
284°
282°
276°
286°
273°
March
191°
116°
287°
246°
310°
April
315°
319°
301°
291°
May
108°
357°
188°
036°
June
288°
019°
273°
308°
July
288°
251°
210°
279°
August
274°
266°
288°
254°
September
211°
346°
251°
296°
October
266°
256°
207°
279°
November
241°
294°
238°
268°
December
205°
267°
277°
266°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.