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
93.1
97
95
91
89
February
90.7
93
96
98
75
March
93.0
95
88
95
94
88
April
95.1
91
96
97
97
May
95.6
99
95
92
97
June
95.0
96
98
96
92
July
98.6
99
99
100
97
August
96.4
100
99
96
94
September
87.4
88
95
80
October
89.9
92
93
85
November
91.5
100
91
98
85
December
95.8
100
93
94
97
Average
93.9
94.7
95.3
94.7
93.2
91.5
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
0.6
1
0
0
2
February
1.2
3
3
1
-2
March
6.6
8
3
9
7
5
April
10.6
11
8
12
11
May
16.1
19
14
15
17
June
20.7
20
20
24
20
July
28.2
28
29
31
25
August
27.9
31
30
26
28
September
23.8
24
24
23
October
13.8
15
15
12
November
3.7
2
-2
7
7
December
1.6
4
-2
2
3
Average
11.3
3.8
11.1
12.4
13.1
16.1
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
-10.8
-11
-9
-11
-6
February
-9.1
-5
-9
-10
-12
March
-5.4
-4
-7
-4
-4
-1
April
-3.3
-2
-4
-3
-2
May
2.8
6
2
1
4
June
7.2
9
8
6
6
July
9.6
10
9
13
8
August
9.5
13
12
8
9
September
5.3
7
4
5
October
0.0
1
1
-2
November
-8.6
-12
-12
-3
-5
December
-9.3
-8
-11
-9
-8
Average
-2.4
-7.2
-2.8
-2.8
-1.5
1.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
0.0
0
0
0
0
February
0.0
0
0
0
0
March
0.0
0
0
0
0
0
April
0.0
0
0
0
0
May
0.0
0
0
0
0
June
0.0
0
0
0
0
July
0.0
0
0
0
0
August
0.0
0
0
0
0
September
0.0
0
0
0
October
0.0
0
0
0
November
0.0
0
0
0
0
December
0.0
0
0
0
0
Average
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
4.0
5
4
4
4
February
4.7
4
5
5
5
March
5.2
4
5
6
5
5
April
6.5
7
6
7
5
May
4.8
5
6
5
4
June
4.3
4
5
6
3
July
3.7
4
4
4
3
August
4.5
3
5
5
4
September
4.4
4
5
4
October
4.3
5
4
5
November
4.9
1
4
6
6
December
3.8
3
4
4
4
Average
4.5
4.1
4.7
4.9
4.9
4.0
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
209°
262°
276°
197°
February
196°
339°
342°
249°
March
337°
312°
336°
298°
293°
April
285°
304°
339°
291°
May
021°
321°
332°
341°
June
338°
293°
324°
333°
July
336°
334°
344°
341°
August
034°
341°
343°
330°
September
347°
329°
335°
October
317°
319°
305°
November
014°
277°
230°
219°
December
161°
255°
255°
258°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.