Solon
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Solon clear sky chart from 2005-11-06 to 2024-01-31.

This page is a summary of past forecasts. Even though it's based only on forecasts, some people use these pages as clue to a site's climate. But climate data based on actual observation should be preferred (if you can find it!).

Cloud, Transparency and Seeing forecasts are summarized individually. But because good observing conditions require a combination of minimum cloud cover, transparency and seeing, the individual forecast summaries can be difficult to interpret. The observing conditions section counts the combinations of conditions needed for common types of astronomical observation.

Observing Conditions

The following tables count the occurrence of the combinations of forecast and darkness conditions needed for different observations. Conditions are rated by by what percentage of the hours the observation would likely be attempted are usable.
Observation TypeMinimum conditions for hour to be usableOut of hours
Clear of CloudsTransparencySeeingSky Brightness
Planetary:50%(no limit)Average(no limit)Nighttime Hours
Deep Sky:70%Average(no limit)5.9Nighttime Hours
CCD Imaging:70%Below AveragePoor(no limit)Nighttime Hours

Percentages are of nighttime hours per month, or per year, when a particular observing conditions was met. Deep Sky percentages never exceed 50% because the moon is up half the time. Deep sky percentages are much lower for charts at high latitudes because of fewer dark hours in the summer.

Overall

PlanetaryData
Pts
Deep Sky
Max 60%
Data
Pts
Both Planetary and Deep Sky
Max 60%
Data
Pts
Either Planetary or Deep SkyData
Pts
CCD ImagingData
Pts
Night
29%
23421
14%
75136
9%
23365
36%
23365
16%
54444

By Month

MonthDays of MonthPlanetaryData
Pts
Deep Sky
Max 60%
Data
Pts
Both Planetary and Deep Sky
Max 60%
Data
Pts
Either Planetary or Deep SkyData
Pts
CCD ImagingData
Pts
January1st to 10thNight
9%
759
9%
2459
3%
757
16%
757
6%
2047
January11th to 20thNight
10%
760
6%
2470
3%
760
14%
760
5%
2098
January21st to endNight
12%
835
8%
2711
3%
835
18%
835
6%
2287
February1st to 10thNight
10%
720
7%
2340
2%
720
16%
720
7%
1925
February11th to 20thNight
14%
702
9%
2234
4%
700
20%
700
8%
1804
February21st to endNight
10%
592
11%
1776
2%
592
20%
592
9%
1414
March1st to 10thNight
18%
720
15%
2025
7%
720
26%
720
13%
1513
March11th to 20thNight
23%
720
17%
1980
8%
720
31%
720
17%
1439
March21st to endNight
21%
792
16%
2178
8%
792
27%
792
16%
1636
April1st to 10thNight
23%
720
13%
1937
5%
720
28%
720
18%
1420
April11th to 20thNight
23%
584
18%
1648
5%
584
32%
584
20%
1157
April21st to endNight
25%
540
17%
1620
6%
540
34%
540
20%
1120
May1st to 10thNight
29%
540
12%
1620
6%
540
34%
540
18%
1149
May11th to 20thNight
37%
531
16%
1593
12%
531
42%
531
22%
1084
May21st to endNight
48%
520
15%
1683
12%
520
54%
520
30%
1006
June1st to 10thNight
45%
360
16%
1440
16%
360
53%
360
21%
857
June11th to 20thNight
43%
360
17%
1440
16%
360
54%
360
23%
844
June21st to endNight
47%
360
18%
1440
17%
360
57%
360
24%
835
July1st to 10thNight
60%
498
16%
1548
16%
498
63%
498
32%
927
July11th to 20thNight
56%
522
18%
1566
15%
522
60%
522
35%
928
July21st to endNight
58%
591
18%
1672
14%
558
61%
558
30%
1037
August1st to 10thNight
61%
537
19%
1600
15%
534
62%
534
32%
957
August11th to 20thNight
59%
534
22%
1598
16%
534
63%
534
29%
995
August21st to endNight
57%
620
23%
1808
16%
620
61%
620
33%
1099
September1st to 10thNight
54%
720
21%
1880
13%
720
57%
720
31%
1226
September11th to 20thNight
57%
720
26%
1980
18%
720
62%
720
36%
1189
September21st to endNight
42%
720
21%
1980
15%
720
47%
720
26%
1337
October1st to 10thNight
40%
720
20%
2106
15%
720
46%
720
27%
1347
October11th to 20thNight
26%
720
16%
2160
10%
720
35%
720
17%
1531
October21st to endNight
19%
792
16%
2376
8%
792
29%
792
14%
1771
November1st to 10thNight
31%
740
18%
2401
13%
740
39%
740
20%
1588
November11th to 20thNight
16%
760
14%
2514
7%
760
25%
760
11%
1875
November21st to endNight
15%
760
11%
2660
6%
760
22%
760
9%
2092
December1st to 10thNight
13%
760
6%
2660
4%
760
16%
760
7%
2171
December11th to 20thNight
12%
760
8%
3267
2%
759
20%
759
5%
2611
December21st to endNight
9%
832
4%
4766
1%
817
16%
817
3%
4128

Individual Forecasts

The length of each colored bar in the "occurrence of each Forecast" column is proportional to the number of times the chart forecast that color. The percentages are of the total number of hours per month, or per year, with a particular forecast. The colors as the same as those used in clear sky charts.

Note: Transparency probabilities are only counted for those hours that have 30% or less cloud cover. Seeing probabilities are only counted for those hours that have 80% or less cloud cover. If that's too tricky, try Observing Conditions instead.

Overall

Occurrence of each ForecastData
Points
Cloud CoverDay
17%11%5%8%6%35%5%5%7%30%
74757
Night
17%12%5%8%6%3445%6%30%
75372
TransparencyDay
54%411%19%11%1
74478
Night
55%410%18%11%2
75170
SeeingDay
25%14%29%19%9%3
13512
Night
24%14%27%23%10%1
23429

By Month

Percentage Cloud Cover SE (2006-)
Color Meanings:
Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 10thDay
17%18%9%12%8%5%444415%
1706
11th to 20thDay
19%20%10%13%7%4434412%
1710
21st to endDay
17%19%10%15%9%4344410%
1872
February1st to 10thDay
18%20%8%11%10%4333417%
1620
11th to 20thDay
16%15%7%14%10%44445%17%
1613
21st to endDay
18%16%5%13%7%345%5%421%
1480
March1st to 10thDay
19%12%7%8%5%3345%6%26%
1934
11th to 20thDay
17%15%5%9%6%43446%28%
1980
21st to endDay
23%12%6%8%5%34446%26%
2178
April1st to 10thDay
17%12%6%6%5%3445%6%31%
2022
11th to 20thDay
19%12%45%6%35%5%46%32%
2276
21st to endDay
21%12%47%424445%33%
2340
May1st to 10thDay
18%9%36%7%45%6%5%6%30%
2340
11th to 20thDay
20%8%36%5%35%5%5%7%34%
2301
21st to endDay
11%6%37%6%46%6%6%9%37%
2589
June1st to 10thDay
16%6%26%6%45%6%6%8%36%
2520
11th to 20thDay
14%7%26%5%35%5%6%8%38%
2520
21st to endDay
13%5%35%5%35%5%6%10%40%
2520
July1st to 10thDay
10%6%36%5%35%46%10%41%
2361
11th to 20thDay
13%6%26%5%446%6%10%38%
2340
21st to endDay
10%6%36%6%46%5%6%10%38%
2547
August1st to 10thDay
10%6%36%6%45%6%6%9%39%
2327
11th to 20thDay
11%6%36%7%46%8%7%8%34%
2303
21st to endDay
12%6%26%6%46%6%6%9%37%
2530
September1st to 10thDay
16%6%35%5%345%6%8%39%
2077
11th to 20thDay
12%6%26%6%45%5%6%9%40%
1980
21st to endDay
20%7%35%43445%6%38%
1980
October1st to 10thDay
17%7%26%5%345%5%8%37%
1854
11th to 20thDay
22%10%37%445%45%6%31%
1800
21st to endDay
26%12%47%6%35%45%5%25%
1980
November1st to 10thDay
14%12%47%6%345%47%35%
1672
11th to 20thDay
19%17%47%5%34446%26%
1663
21st to endDay
19%19%7%8%6%35%45%6%18%
1520
December1st to 10thDay
17%21%11%11%7%3443414%
1520
11th to 20thDay
19%18%9%15%5%3445%5%14%
1910
21st to endDay
24%27%8%10%6%343339%
2872
January1st to 10thNight
18%19%9%13%7%3443417%
2459
11th to 20thNight
20%19%7%13%7%4433415%
2470
21st to endNight
18%19%8%13%8%45%33415%
2711
February1st to 10thNight
21%16%6%12%8%34445%17%
2340
11th to 20thNight
17%15%6%12%8%44445%19%
2232
21st to endNight
21%14%5%11%7%34435%23%
1776
March1st to 10thNight
17%12%7%8%6%345%5%5%29%
2025
11th to 20thNight
17%11%5%7%5%345%5%6%33%
1980
21st to endNight
19%12%6%8%5%34445%30%
2178
April1st to 10thNight
17%13%5%6%5%35%5%47%31%
1937
11th to 20thNight
16%10%36%6%36%46%7%33%
1648
21st to endNight
15%11%45%5%35%5%6%6%35%
1620
May1st to 10thNight
18%9%47%6%45%5%5%6%32%
1620
11th to 20thNight
16%9%46%5%3447%8%35%
1592
21st to endNight
10%5%25%4346%7%11%41%
1682
June1st to 10thNight
10%6%35%5%37%7%6%7%41%
1440
11th to 20thNight
10%5%26%6%35%5%5%9%42%
1440
21st to endNight
12%5%15%5%35%5%7%11%40%
1440
July1st to 10thNight
8%6%35%6%345%5%8%49%
1593
11th to 20thNight
8%5%26%5%345%6%9%46%
1620
21st to endNight
9%5%35%7%46%46%8%44%
1771
August1st to 10thNight
6%6%35%5%36%5%5%9%47%
1611
11th to 20thNight
11%6%35%5%445%5%9%44%
1598
21st to endNight
10%5%25%5%345%6%8%45%
1808
September1st to 10thNight
13%6%25%5%45%5%5%7%44%
1880
11th to 20thNight
10%5%245%345%5%7%50%
1980
21st to endNight
15%8%27%6%4445%6%40%
1980
October1st to 10thNight
14%7%25%5%345%5%8%43%
2106
11th to 20thNight
21%8%37%6%35%45%6%32%
2160
21st to endNight
27%10%35%5%3345%6%28%
2376
November1st to 10thNight
16%9%36%6%3436%6%37%
2401
11th to 20thNight
18%17%6%7%6%4335%6%26%
2514
21st to endNight
21%18%5%7%6%4445%5%21%
2660
December1st to 10thNight
21%19%8%10%5%34345%17%
2660
11th to 20thNight
18%19%9%11%6%34445%19%
3285
21st to endNight
25%23%9%9%6%3433410%
4779

Transparency (when cloud cover <= 30%)
Color Meanings:
Too cloudy to forecast Poor Below Average Average Above average Transparent
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 10thDay
74%49%10%4
1707
11th to 20thDay
78%310%8%2
1710
21st to endDay
79%36%8%3
1872
February1st to 10thDay
73%28%12%5%
1620
11th to 20thDay
72%37%12%5%
1622
21st to endDay
66%410%12%7%1
1480
March1st to 10thDay
59%411%19%6%
1934
11th to 20thDay
60%39%17%10%2
1980
21st to endDay
61%37%18%9%2
2178
April1st to 10thDay
54%411%18%13%1
2022
11th to 20thDay
54%410%17%13%2
2276
21st to endDay
54%310%20%10%3
2340
May1st to 10thDay
54%5%10%20%10%2
2340
11th to 20thDay
51%411%18%14%2
2305
21st to endDay
43%5%14%24%14%1
2589
June1st to 10thDay
45%5%11%25%13%1
2520
11th to 20thDay
43%5%15%21%14%1
2520
21st to endDay
39%413%25%16%2
2520
July1st to 10thDay
41%411%26%17%2
2296
11th to 20thDay
41%5%13%25%15%2
2271
21st to endDay
39%5%13%25%16%2
2405
August1st to 10thDay
40%5%14%27%13%1
2314
11th to 20thDay
45%6%13%23%12%2
2303
21st to endDay
42%5%13%22%15%3
2530
September1st to 10thDay
42%5%14%21%15%3
2077
11th to 20thDay
40%415%25%16%1
1980
21st to endDay
47%49%25%15%1
1980
October1st to 10thDay
45%5%11%23%14%1
1854
11th to 20thDay
54%5%11%20%9%1
1800
21st to endDay
61%411%14%9%1
1980
November1st to 10thDay
49%5%10%21%14%1
1672
11th to 20thDay
60%49%17%7%3
1663
21st to endDay
69%48%13%6%
1520
December1st to 10thDay
75%48%11%3
1520
11th to 20thDay
74%47%12%3
1906
21st to endDay
82%28%6%1
2872
January1st to 10thNight
72%37%11%6%
2459
11th to 20thNight
75%39%10%31
2470
21st to endNight
74%37%12%41
2711
February1st to 10thNight
71%39%12%5%
2340
11th to 20thNight
68%37%15%6%
2234
21st to endNight
66%48%14%7%1
1776
March1st to 10thNight
56%49%21%9%1
2025
11th to 20thNight
52%5%11%18%12%2
1980
21st to endNight
57%47%18%12%2
2178
April1st to 10thNight
53%411%17%13%2
1937
11th to 20thNight
51%411%17%15%3
1648
21st to endNight
48%5%11%20%14%3
1620
May1st to 10thNight
53%410%18%12%3
1620
11th to 20thNight
47%5%11%19%14%4
1593
21st to endNight
35%6%17%25%15%2
1683
June1st to 10thNight
41%5%10%26%15%3
1440
11th to 20thNight
40%414%20%19%2
1440
21st to endNight
37%7%12%26%17%2
1440
July1st to 10thNight
36%5%10%25%20%4
1548
11th to 20thNight
34%413%27%19%3
1566
21st to endNight
38%413%24%17%3
1672
August1st to 10thNight
34%6%13%29%17%1
1600
11th to 20thNight
38%6%14%28%13%2
1598
21st to endNight
36%411%27%18%3
1808
September1st to 10thNight
39%5%11%26%16%3
1880
11th to 20thNight
33%5%13%28%21%1
1980
21st to endNight
45%410%21%19%1
1980
October1st to 10thNight
40%5%13%22%19%1
2106
11th to 20thNight
52%49%22%11%1
2160
21st to endNight
58%410%18%9%2
2376
November1st to 10thNight
47%411%22%13%3
2401
11th to 20thNight
61%39%17%8%2
2514
21st to endNight
66%410%15%5%
2660
December1st to 10thNight
71%39%11%5%
2660
11th to 20thNight
69%410%14%3
3288
21st to endNight
79%39%7%1
4779

Seeing (when cloud cover <= 80%)
Color Meanings:
Too cloudy to forecast Bad 1/5 Poor 2/5 Average 3/5 Good 4/5 Excellent 5/5
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 10thDay
35%24%28%10%3
270
11th to 20thDay
37%26%28%6%11
270
21st to endDay
34%30%27%7%2
294
February1st to 10thDay
39%21%35%5%
240
11th to 20thDay
38%30%28%3
240
21st to endDay
43%28%25%4
198
March1st to 10thDay
32%21%32%11%3
374
11th to 20thDay
33%19%32%12%31
420
21st to endDay
37%19%26%14%3
462
April1st to 10thDay
28%22%29%16%6%
420
11th to 20thDay
33%17%28%14%8%2
412
21st to endDay
35%15%31%14%5%1
420
May1st to 10thDay
28%16%31%18%43
423
11th to 20thDay
27%9%31%23%6%3
447
21st to endDay
17%8%32%26%13%4
485
June1st to 10thDay
19%9%37%22%9%3
450
11th to 20thDay
19%10%28%28%12%3
450
21st to endDay
17%10%33%24%12%4
450
July1st to 10thDay
14%5%23%30%19%8%
445
11th to 20thDay
16%5%27%29%18%6%
444
21st to endDay
12%8%28%29%16%7%
488
August1st to 10thDay
14%424%30%21%7%
446
11th to 20thDay
17%6%24%29%15%8%
439
21st to endDay
14%5%27%28%18%8%
495
September1st to 10thDay
19%6%24%26%18%6%
450
11th to 20thDay
13%422%30%21%9%
450
21st to endDay
23%10%27%23%12%5%
450
October1st to 10thDay
18%11%29%22%17%3
450
11th to 20thDay
28%18%32%15%6%1
450
21st to endDay
37%16%29%14%3
495
November1st to 10thDay
25%21%29%16%7%1
270
11th to 20thDay
39%17%25%13%41
248
21st to endDay
34%19%39%7%1
180
December1st to 10thDay
34%22%28%12%32
180
11th to 20thDay
32%29%30%8%1
180
21st to endDay
38%24%30%7%
227
January1st to 10thNight
31%24%30%12%3
760
11th to 20thNight
34%23%28%13%2
760
21st to endNight
30%22%30%16%2
835
February1st to 10thNight
32%22%30%15%2
720
11th to 20thNight
29%23%30%17%1
703
21st to endNight
31%23%32%13%1
592
March1st to 10thNight
25%23%30%18%4
720
11th to 20thNight
26%18%30%18%6%1
720
21st to endNight
28%16%30%20%6%1
792
April1st to 10thNight
26%16%30%21%6%
720
11th to 20thNight
22%16%35%18%8%1
584
21st to endNight
23%12%34%25%6%
540
May1st to 10thNight
24%10%29%28%8%1
540
11th to 20thNight
21%7%28%33%9%2
531
21st to endNight
13%330%34%18%2
522
June1st to 10thNight
11%5%31%40%12%1
360
11th to 20thNight
13%5%29%38%14%1
360
21st to endNight
13%6%28%37%16%
360
July1st to 10thNight
10%216%40%28%4
498
11th to 20thNight
10%222%37%24%5%
522
21st to endNight
13%219%41%24%2
591
August1st to 10thNight
9%316%43%25%3
537
11th to 20thNight
14%314%37%28%4
534
21st to endNight
12%321%31%29%4
620
September1st to 10thNight
17%6%16%33%24%3
720
11th to 20thNight
14%218%33%27%4
720
21st to endNight
19%7%26%28%16%4
720
October1st to 10thNight
19%9%28%26%16%3
720
11th to 20thNight
28%13%28%24%7%1
720
21st to endNight
34%13%31%18%4
792
November1st to 10thNight
23%14%28%25%9%1
740
11th to 20thNight
30%20%28%15%6%1
760
21st to endNight
34%18%29%13%5%
760
December1st to 10thNight
35%21%28%12%4
760
11th to 20thNight
30%24%29%14%3
760
21st to endNight
36%19%31%13%1
836
Page generated at 2024-01-28 05:26:35. Version ac07

Copyright 2024 Attilla Danko


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