The Lone Wolf Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the The Lone Wolf Observatory clear sky chart from 2005-11-06 to 2024-11-01.

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
35%
25465
16%
95683
10%
25247
42%
25247
18%
63398

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
19%
944
10%
4408
3%
926
29%
926
9%
3238
January11th to 20thNight
17%
950
8%
4413
4%
930
23%
930
7%
3535
January21st to endNight
18%
1038
7%
4797
3%
1023
25%
1023
8%
3832
February1st to 10thNight
20%
879
12%
2399
4%
879
27%
879
17%
1790
February11th to 20thNight
24%
740
19%
2219
8%
740
34%
740
19%
1516
February21st to endNight
17%
628
17%
1884
5%
628
29%
628
16%
1351
March1st to 10thNight
22%
758
17%
3687
6%
745
27%
745
11%
2302
March11th to 20thNight
28%
757
21%
3658
9%
740
38%
740
17%
1969
March21st to endNight
27%
633
9%
3428
10%
615
34%
615
8%
2531
April1st to 10thNight
27%
570
16%
1900
9%
570
38%
570
20%
1235
April11th to 20thNight
27%
563
19%
1875
11%
563
38%
563
20%
1241
April21st to endNight
30%
570
15%
1780
7%
570
39%
570
19%
1235
May1st to 10thNight
33%
565
17%
2786
9%
559
39%
559
15%
1749
May11th to 20thNight
40%
551
13%
2618
10%
541
47%
541
17%
1555
May21st to endNight
46%
608
14%
2705
10%
593
52%
593
19%
1558
June1st to 10thNight
52%
570
17%
1520
11%
570
57%
570
36%
937
June11th to 20thNight
51%
570
19%
1520
12%
570
56%
570
36%
923
June21st to endNight
49%
570
17%
1520
9%
570
53%
570
29%
1021
July1st to 10thNight
63%
548
14%
2409
12%
535
67%
535
22%
1479
July11th to 20thNight
60%
541
18%
2221
16%
533
64%
533
29%
1179
July21st to endNight
67%
603
16%
2475
15%
569
72%
569
27%
1414
August1st to 10thNight
69%
553
21%
2458
20%
545
71%
545
24%
1425
August11th to 20thNight
67%
549
18%
2689
21%
543
72%
543
24%
1478
August21st to endNight
63%
607
18%
3074
23%
605
69%
605
24%
1642
September1st to 10thNight
59%
570
25%
1900
25%
570
64%
570
33%
1074
September11th to 20thNight
63%
689
32%
2019
28%
689
68%
689
39%
1143
September21st to endNight
50%
760
23%
2090
16%
760
55%
760
31%
1337
October1st to 10thNight
50%
760
26%
2109
20%
760
54%
760
33%
1296
October11th to 20thNight
32%
760
20%
2308
10%
760
43%
760
25%
1448
October21st to endNight
27%
836
17%
2717
10%
836
36%
836
19%
1824
November1st to 10thNight
27%
743
25%
2413
15%
743
41%
743
25%
1452
November11th to 20thNight
24%
760
18%
2470
9%
760
35%
760
18%
1657
November21st to endNight
23%
783
18%
2493
9%
783
34%
783
19%
1701
December1st to 10thNight
19%
950
12%
2660
4%
950
26%
950
17%
1962
December11th to 20thNight
21%
950
13%
3216
4%
948
29%
948
13%
2345
December21st to endNight
12%
1039
6%
4845
2%
1026
20%
1026
6%
4024

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
13%9%37%5%4446%7%37%
101220
Night
14%10%47%44435%6%37%
97791
TransparencyDay
45%6%12%22%13%2
101009
Night
47%6%11%21%13%2
97673
SeeingDay
17%11%31%25%12%4
15781
Night
18%11%30%29%12%1
25608

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
13%15%8%9%5%5%5%45%5%26%
2527
11th to 20thDay
14%14%8%13%5%5%5%8%7%418%
2530
21st to endDay
20%26%6%8%433236%20%
2826
February1st to 10thDay
16%15%5%8%6%5%4346%27%
1779
11th to 20thDay
14%11%39%6%4436%5%35%
1848
21st to endDay
14%14%410%5%4435%7%29%
1570
March1st to 10thDay
16%14%38%443345%34%
3120
11th to 20thDay
10%7%38%5%5%5%46%7%39%
3262
21st to endDay
18%13%6%12%6%5%445%5%20%
4165
April1st to 10thDay
17%13%37%44435%6%31%
2280
11th to 20thDay
17%9%36%5%5%5%45%6%36%
2254
21st to endDay
20%8%37%44446%7%33%
2399
May1st to 10thDay
17%8%27%5%5%5%46%8%34%
4082
11th to 20thDay
15%7%26%44436%8%41%
4234
21st to endDay
10%6%27%44446%9%44%
4824
June1st to 10thDay
10%5%26%5%45%46%8%45%
2660
11th to 20thDay
9%6%27%5%4447%7%46%
2660
21st to endDay
11%6%26%5%6%5%6%7%9%37%
2660
July1st to 10thDay
11%8%37%6%6%6%47%9%34%
4440
11th to 20thDay
7%426%44446%10%48%
4440
21st to endDay
8%6%27%5%5%5%5%7%9%41%
4813
August1st to 10thDay
9%5%26%5%4446%8%45%
4277
11th to 20thDay
9%5%25%445%47%8%46%
3773
21st to endDay
7%5%25%45%5%45%10%48%
4180
September1st to 10thDay
12%6%26%45%5%35%7%47%
2280
11th to 20thDay
10%6%2434436%7%51%
2141
21st to endDay
11%7%26%45%45%7%8%42%
2090
October1st to 10thDay
13%8%26%44435%6%46%
2068
11th to 20thDay
19%8%37%45%4346%37%
1872
21st to endDay
20%9%36%445%35%7%33%
1881
November1st to 10thDay
12%8%35%43436%7%44%
1672
11th to 20thDay
15%11%38%445%35%7%34%
1710
21st to endDay
19%10%38%5%34345%36%
1682
December1st to 10thDay
15%16%48%5%5%5%346%29%
1520
11th to 20thDay
13%15%5%10%5%45%36%5%28%
1918
21st to endDay
22%20%7%12%5%5%434414%
2783
January1st to 10thNight
16%16%7%11%5%4424428%
4428
11th to 20thNight
15%18%8%13%5%445%6%418%
4440
21st to endNight
23%19%6%8%44423421%
4838
February1st to 10thNight
16%14%5%8%6%4335%5%31%
2399
11th to 20thNight
13%12%47%5%44446%37%
2218
21st to endNight
19%12%48%5%4325%5%34%
1884
March1st to 10thNight
17%13%46%333345%39%
3733
11th to 20thNight
10%7%26%44435%6%48%
3718
21st to endNight
20%11%7%10%5%4434427%
3476
April1st to 10thNight
15%10%36%435%35%8%37%
1900
11th to 20thNight
19%8%36%5%4335%6%39%
1875
21st to endNight
18%9%27%45%5%45%6%36%
1780
May1st to 10thNight
17%8%37%5%5%446%8%34%
2813
11th to 20thNight
15%8%26%44436%9%38%
2662
21st to endNight
11%7%37%44436%6%44%
2743
June1st to 10thNight
10%5%26%44446%8%49%
1520
11th to 20thNight
8%6%26%45%447%9%46%
1520
21st to endNight
11%7%26%445%46%8%42%
1520
July1st to 10thNight
11%427%5%5%6%5%6%8%40%
2530
11th to 20thNight
6%5%25%44446%8%53%
2530
21st to endNight
5%425%5%5%7%48%9%46%
2750
August1st to 10thNight
7%5%27%45%5%46%8%47%
2656
11th to 20thNight
8%5%26%345%46%8%51%
3040
21st to endNight
8%5%25%43435%9%52%
3476
September1st to 10thNight
9%6%36%44335%6%52%
1900
11th to 20thNight
9%5%2433435%7%55%
2019
21st to endNight
11%5%37%445%46%7%45%
2090
October1st to 10thNight
12%5%25%44345%6%50%
2109
11th to 20thNight
16%7%26%434346%45%
2308
21st to endNight
21%9%27%44335%7%36%
2717
November1st to 10thNight
12%9%25%433346%47%
2413
11th to 20thNight
14%10%38%45%436%6%36%
2470
21st to endNight
18%10%37%444346%37%
2493
December1st to 10thNight
17%11%310%6%4446%6%30%
2660
11th to 20thNight
15%15%48%5%5%3346%32%
3279
21st to endNight
24%18%6%10%5%5%4345%16%
4884

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
59%6%14%14%6%
2528
11th to 20thDay
65%5%11%12%8%
2530
21st to endDay
70%47%14%5%
2826
February1st to 10thDay
59%6%12%14%9%2
1779
11th to 20thDay
52%411%21%10%2
1858
21st to endDay
55%7%10%19%6%2
1570
March1st to 10thDay
52%6%9%21%10%2
3120
11th to 20thDay
42%6%12%28%11%1
3262
21st to endDay
64%8%13%12%3
4165
April1st to 10thDay
53%7%9%19%12%
2280
11th to 20thDay
48%7%10%21%11%4
2254
21st to endDay
49%7%13%18%12%2
2399
May1st to 10thDay
46%8%12%24%10%1
4120
11th to 20thDay
40%7%12%27%13%
4238
21st to endDay
35%7%12%22%20%4
4837
June1st to 10thDay
35%8%13%25%18%2
2660
11th to 20thDay
35%7%11%25%20%3
2660
21st to endDay
41%9%14%20%14%2
2660
July1st to 10thDay
46%6%13%21%13%2
4371
11th to 20thDay
31%6%17%29%16%1
4365
21st to endDay
38%7%17%17%19%2
4662
August1st to 10thDay
35%7%16%28%14%1
4262
11th to 20thDay
33%7%11%32%16%1
3810
21st to endDay
31%6%13%27%20%3
4179
September1st to 10thDay
36%6%12%25%18%4
2280
11th to 20thDay
30%6%12%28%20%3
2141
21st to endDay
37%7%10%25%19%1
2090
October1st to 10thDay
38%6%11%26%17%2
2068
11th to 20thDay
49%410%22%14%1
1872
21st to endDay
51%412%22%10%2
1881
November1st to 10thDay
38%5%15%23%16%2
1672
11th to 20thDay
49%6%13%21%11%1
1710
21st to endDay
53%5%9%23%10%
1682
December1st to 10thDay
56%5%13%18%7%
1520
11th to 20thDay
56%6%11%20%7%1
1915
21st to endDay
77%47%9%3
2783
January1st to 10thNight
60%412%16%7%1
4428
11th to 20thNight
67%5%11%11%5%
4440
21st to endNight
67%49%14%5%
4838
February1st to 10thNight
57%411%16%10%2
2399
11th to 20thNight
49%411%21%13%1
2219
21st to endNight
53%410%19%11%2
1884
March1st to 10thNight
48%5%11%23%10%3
3733
11th to 20thNight
37%6%11%27%17%2
3718
21st to endNight
59%7%9%19%6%1
3476
April1st to 10thNight
45%5%12%23%13%1
1900
11th to 20thNight
46%5%9%20%17%4
1875
21st to endNight
48%7%9%20%14%2
1780
May1st to 10thNight
46%6%13%21%12%2
2840
11th to 20thNight
41%8%14%27%10%1
2663
21st to endNight
38%8%11%17%20%6%
2751
June1st to 10thNight
33%7%13%25%20%3
1520
11th to 20thNight
32%6%14%23%23%2
1520
21st to endNight
38%9%13%22%16%3
1520
July1st to 10thNight
40%6%15%22%11%5%
2490
11th to 20thNight
28%6%13%27%24%2
2482
21st to endNight
32%7%18%19%21%4
2662
August1st to 10thNight
33%8%15%27%16%1
2647
11th to 20thNight
31%6%14%28%21%1
3068
21st to endNight
30%6%11%32%17%4
3476
September1st to 10thNight
32%5%12%25%22%3
1900
11th to 20thNight
28%6%8%29%27%2
2019
21st to endNight
37%6%10%28%16%2
2090
October1st to 10thNight
34%6%10%28%20%3
2109
11th to 20thNight
41%49%24%20%2
2308
21st to endNight
48%5%11%22%13%1
2717
November1st to 10thNight
39%410%25%18%3
2413
11th to 20thNight
48%5%12%22%12%1
2470
21st to endNight
49%412%23%11%
2493
December1st to 10thNight
53%6%12%20%8%1
2660
11th to 20thNight
55%5%12%18%9%1
3281
21st to endNight
71%5%8%11%4
4884

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
22%16%34%22%5%
270
11th to 20thDay
26%18%36%14%5%1
270
21st to endDay
24%18%37%18%21
297
February1st to 10thDay
24%17%41%16%3
270
11th to 20thDay
27%17%36%17%31
270
21st to endDay
24%20%40%12%2
225
March1st to 10thDay
20%24%41%13%2
270
11th to 20thDay
27%16%35%17%5%
313
21st to endDay
28%16%30%19%6%1
506
April1st to 10thDay
25%16%32%20%6%
460
11th to 20thDay
23%19%26%21%10%1
452
21st to endDay
23%16%36%16%8%1
460
May1st to 10thDay
22%14%32%23%7%2
463
11th to 20thDay
19%12%32%25%10%2
575
21st to endDay
13%9%34%27%13%5%
734
June1st to 10thDay
11%10%32%30%13%5%
680
11th to 20thDay
12%6%34%29%16%3
680
21st to endDay
12%9%36%28%11%4
680
July1st to 10thDay
9%5%25%31%19%11%
671
11th to 20thDay
11%428%32%16%9%
668
21st to endDay
8%427%36%19%6%
739
August1st to 10thDay
7%423%33%23%10%
595
11th to 20thDay
10%6%20%30%24%10%
479
21st to endDay
7%220%39%23%9%
539
September1st to 10thDay
14%6%22%32%21%6%
490
11th to 20thDay
10%319%31%26%10%
490
21st to endDay
14%11%25%26%18%7%
490
October1st to 10thDay
17%7%28%28%15%4
468
11th to 20thDay
19%22%32%19%6%1
300
21st to endDay
29%13%37%16%5%
330
November1st to 10thDay
16%13%39%23%6%3
270
11th to 20thDay
23%18%37%16%7%
270
21st to endDay
26%12%39%20%3
270
December1st to 10thDay
19%22%37%17%5%
270
11th to 20thDay
20%17%41%20%3
270
21st to endDay
26%22%38%13%1
297
January1st to 10thNight
20%17%36%23%3
950
11th to 20thNight
23%17%35%20%41
950
21st to endNight
22%14%36%25%4
1045
February1st to 10thNight
23%13%38%22%4
879
11th to 20thNight
21%15%35%24%3
743
21st to endNight
24%17%37%19%3
628
March1st to 10thNight
21%15%38%21%6%
760
11th to 20thNight
16%13%38%26%6%1
760
21st to endNight
23%14%30%25%7%1
637
April1st to 10thNight
20%14%35%25%6%1
570
11th to 20thNight
22%13%33%23%9%1
563
21st to endNight
21%11%32%27%8%1
570
May1st to 10thNight
20%6%34%30%9%
570
11th to 20thNight
18%429%34%14%1
561
21st to endNight
12%6%26%36%19%1
617
June1st to 10thNight
10%425%45%15%1
570
11th to 20thNight
11%5%28%41%15%1
570
21st to endNight
12%325%40%19%1
570
July1st to 10thNight
7%320%40%26%4
555
11th to 20thNight
8%322%38%27%3
552
21st to endNight
5%218%47%25%2
624
August1st to 10thNight
5%113%49%27%4
567
11th to 20thNight
8%313%40%32%4
564
21st to endNight
9%218%39%30%3
627
September1st to 10thNight
11%418%35%27%4
570
11th to 20thNight
9%5%17%37%29%4
689
21st to endNight
11%7%24%34%22%3
760
October1st to 10thNight
14%6%26%34%18%2
760
11th to 20thNight
20%14%31%26%9%1
760
21st to endNight
26%14%29%24%7%
836
November1st to 10thNight
18%12%39%20%10%2
743
11th to 20thNight
19%18%34%23%5%1
760
21st to endNight
23%13%37%22%5%
783
December1st to 10thNight
21%16%38%21%4
950
11th to 20thNight
23%14%37%23%3
950
21st to endNight
30%16%33%19%2
1045
Page generated at 2024-10-29 10:20:44. Version ac07

Copyright © 2024 Attilla Danko.


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