This page made possible by the sponsorship of: Anonymous.

Killarney Provincial Park Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Killarney Provincial Park Observatory clear sky chart from 2005-11-06 to 2024-01-16.

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%
23470
14%
74853
8%
23414
36%
23414
17%
53069

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
17%
950
10%
2838
3%
946
23%
946
11%
2231
January11th to 20thNight
19%
926
9%
2634
3%
926
23%
926
12%
2079
January21st to endNight
26%
862
13%
2644
7%
862
32%
862
14%
1984
February1st to 10thNight
18%
720
11%
2340
4%
720
27%
720
12%
1755
February11th to 20thNight
22%
701
14%
2273
5%
699
32%
699
13%
1658
February21st to endNight
18%
592
13%
1822
4%
592
27%
592
12%
1367
March1st to 10thNight
22%
720
16%
2064
7%
720
31%
720
19%
1425
March11th to 20thNight
24%
720
17%
1980
7%
720
33%
720
20%
1393
March21st to endNight
28%
792
18%
2178
8%
792
37%
792
22%
1511
April1st to 10thNight
25%
692
14%
1863
5%
692
31%
692
20%
1346
April11th to 20thNight
33%
533
21%
1597
9%
533
41%
533
22%
1066
April21st to endNight
30%
540
14%
1620
7%
540
35%
540
17%
1153
May1st to 10thNight
37%
540
14%
1620
10%
540
43%
540
22%
1099
May11th to 20thNight
38%
390
19%
1451
16%
390
49%
390
21%
887
May21st to endNight
41%
389
15%
1479
14%
388
51%
388
24%
868
June1st to 10thNight
38%
360
13%
1260
10%
360
46%
360
22%
795
June11th to 20thNight
44%
360
16%
1260
14%
360
50%
360
25%
756
June21st to endNight
42%
360
13%
1260
11%
360
48%
360
23%
791
July1st to 10thNight
55%
350
19%
1225
17%
350
62%
350
35%
645
July11th to 20thNight
54%
348
19%
1218
18%
348
60%
348
29%
704
July21st to endNight
53%
572
14%
1568
12%
541
56%
541
31%
974
August1st to 10thNight
52%
537
15%
1600
12%
534
56%
534
30%
994
August11th to 20thNight
52%
534
19%
1598
12%
534
57%
534
30%
983
August21st to endNight
48%
594
19%
1782
11%
594
55%
594
27%
1137
September1st to 10thNight
45%
688
18%
1788
9%
688
49%
688
31%
1148
September11th to 20thNight
48%
720
21%
1980
14%
720
53%
720
34%
1219
September21st to endNight
39%
720
20%
1980
13%
720
45%
720
26%
1345
October1st to 10thNight
35%
720
17%
2131
12%
720
42%
720
22%
1466
October11th to 20thNight
23%
720
15%
2160
7%
720
33%
720
15%
1595
October21st to endNight
21%
792
12%
2488
6%
792
29%
792
12%
1901
November1st to 10thNight
27%
740
16%
2481
10%
740
36%
740
15%
1725
November11th to 20thNight
22%
760
12%
2660
7%
760
30%
760
10%
1990
November21st to endNight
16%
760
10%
2660
5%
760
23%
760
9%
2083
December1st to 10thNight
15%
779
10%
2679
3%
779
23%
779
8%
2104
December11th to 20thNight
15%
950
11%
3478
2%
948
23%
948
10%
2618
December21st to endNight
15%
1039
5%
5194
2%
1026
19%
1026
5%
4274

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
16%9%47%6%345%5%7%35%
74678
Night
16%11%47%6%3445%7%33%
75110
TransparencyDay
49%5%13%21%11%1
74379
Night
51%6%12%19%10%1
74945
SeeingDay
21%15%32%21%8%2
14116
Night
22%12%29%26%10%1
23478

By Month

Percentage Cloud Cover NE (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
16%18%8%10%6%3344423%
1328
11th to 20thDay
16%15%7%11%6%3435%6%24%
1433
21st to endDay
16%15%6%10%8%3445%5%24%
1710
February1st to 10thDay
12%15%7%9%8%45%5%5%5%25%
1620
11th to 20thDay
13%14%5%8%8%45%436%29%
1573
21st to endDay
13%17%7%11%8%34436%25%
1430
March1st to 10thDay
13%11%5%7%5%345%5%6%36%
1892
11th to 20thDay
13%11%48%7%34446%36%
1980
21st to endDay
16%10%47%7%3345%6%37%
2178
April1st to 10thDay
19%11%47%5%445%47%29%
2112
11th to 20thDay
19%9%36%43445%5%37%
2312
21st to endDay
22%8%36%43435%7%36%
2340
May1st to 10thDay
17%8%36%5%3446%7%38%
2340
11th to 20thDay
17%7%36%4245%5%8%40%
2440
21st to endDay
14%5%25%5%345%6%8%42%
2793
June1st to 10thDay
16%6%35%6%35%5%5%8%38%
2700
11th to 20thDay
12%6%35%6%35%5%5%8%42%
2700
21st to endDay
15%6%36%5%35%45%9%38%
2700
July1st to 10thDay
9%435%5%345%6%8%48%
2700
11th to 20thDay
9%6%25%5%45%5%7%9%42%
2700
21st to endDay
12%425%5%345%6%10%44%
2655
August1st to 10thDay
12%6%35%435%5%6%10%41%
2327
11th to 20thDay
11%6%25%5%345%6%10%43%
2303
21st to endDay
11%6%35%6%35%6%6%9%41%
2574
September1st to 10thDay
12%6%27%6%345%6%6%42%
2151
11th to 20thDay
14%5%245%345%6%8%44%
1980
21st to endDay
19%7%26%6%3445%7%37%
1980
October1st to 10thDay
18%6%36%6%35%5%5%7%36%
1828
11th to 20thDay
26%9%37%6%5%445%6%25%
1800
21st to endDay
26%11%36%7%4445%6%25%
1864
November1st to 10thDay
17%11%47%6%35%5%5%7%29%
1596
11th to 20thDay
17%15%48%6%45%5%6%6%25%
1520
21st to endDay
22%19%5%9%6%34445%19%
1520
December1st to 10thDay
14%20%7%9%6%3446%6%22%
1497
11th to 20thDay
19%14%6%8%6%44446%25%
1671
21st to endDay
25%22%6%9%6%3443416%
2431
January1st to 10thNight
15%16%7%10%6%45%45%6%22%
2838
11th to 20thNight
17%16%6%9%6%3445%6%23%
2634
21st to endNight
15%13%6%9%7%46%45%6%27%
2644
February1st to 10thNight
12%13%6%10%7%45%5%5%6%25%
2340
11th to 20thNight
12%12%6%8%8%46%5%5%5%29%
2273
21st to endNight
13%16%6%8%7%45%5%6%6%25%
1822
March1st to 10thNight
12%9%48%6%4445%5%38%
2054
11th to 20thNight
13%10%47%6%35%5%5%6%36%
1979
21st to endNight
16%9%35%6%34346%39%
2178
April1st to 10thNight
20%9%36%5%35%5%5%6%33%
1863
11th to 20thNight
18%9%35%5%235%47%40%
1597
21st to endNight
19%9%39%6%34446%33%
1620
May1st to 10thNight
13%8%37%7%45%6%6%6%36%
1620
11th to 20thNight
14%6%25%5%35%5%5%10%39%
1451
21st to endNight
11%7%36%4245%5%8%45%
1478
June1st to 10thNight
13%8%25%5%36%6%8%7%39%
1260
11th to 20thNight
11%5%246%36%6%5%10%42%
1260
21st to endNight
14%5%37%5%335%6%9%41%
1260
July1st to 10thNight
9%425%4235%6%9%53%
1260
11th to 20thNight
8%435%5%45%46%8%48%
1260
21st to endNight
10%4246%35%5%7%7%47%
1659
August1st to 10thNight
10%5%35%435%6%6%8%46%
1611
11th to 20thNight
11%6%245%345%5%7%48%
1598
21st to endNight
12%7%35%5%45%45%8%44%
1782
September1st to 10thNight
12%5%25%5%3445%6%48%
1788
11th to 20thNight
13%4243345%48%50%
1980
21st to endNight
18%6%36%43445%8%40%
1980
October1st to 10thNight
19%8%25%6%2445%6%38%
2131
11th to 20thNight
24%9%36%6%345%6%6%30%
2160
21st to endNight
25%11%37%6%3445%6%26%
2488
November1st to 10thNight
18%11%36%5%3445%8%32%
2481
11th to 20thNight
18%12%5%8%8%35%6%5%6%25%
2660
21st to endNight
21%17%47%6%3445%6%22%
2660
December1st to 10thNight
17%18%6%9%6%45%446%21%
2679
11th to 20thNight
18%15%49%6%34446%26%
3526
21st to endNight
25%20%6%9%6%33335%16%
5236

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
65%5%10%15%5%
1329
11th to 20thDay
63%49%14%7%2
1433
21st to endDay
63%48%15%11%1
1710
February1st to 10thDay
62%412%15%6%1
1620
11th to 20thDay
58%5%10%16%10%2
1582
21st to endDay
64%37%18%8%
1430
March1st to 10thDay
50%5%15%14%14%2
1895
11th to 20thDay
50%49%24%10%2
1980
21st to endDay
49%411%20%13%3
2178
April1st to 10thDay
55%5%12%16%11%1
2112
11th to 20thDay
49%49%23%13%1
2312
21st to endDay
49%410%19%14%3
2340
May1st to 10thDay
46%411%22%13%4
2340
11th to 20thDay
44%5%11%22%17%2
2444
21st to endDay
39%7%14%24%13%2
2793
June1st to 10thDay
44%6%12%22%14%1
2700
11th to 20thDay
41%5%11%24%17%1
2700
21st to endDay
45%7%13%24%10%2
2700
July1st to 10thDay
33%5%17%27%17%1
2626
11th to 20thDay
37%7%14%29%12%1
2619
21st to endDay
38%7%15%27%12%1
2507
August1st to 10thDay
39%7%17%24%11%1
2314
11th to 20thDay
38%7%17%28%9%1
2303
21st to endDay
40%7%17%26%9%1
2574
September1st to 10thDay
42%7%13%25%11%1
2151
11th to 20thDay
38%6%15%30%10%
1980
21st to endDay
47%7%15%24%6%
1980
October1st to 10thDay
47%7%14%21%11%1
1828
11th to 20thDay
60%6%13%14%7%
1800
21st to endDay
61%5%13%13%7%1
1864
November1st to 10thDay
54%6%14%19%8%
1596
11th to 20thDay
59%6%12%16%7%
1520
21st to endDay
69%5%9%11%5%
1520
December1st to 10thDay
63%412%14%6%1
1497
11th to 20thDay
61%6%11%16%5%1
1671
21st to endDay
74%47%11%4
2431
January1st to 10thNight
62%6%11%14%7%
2838
11th to 20thNight
62%6%11%13%8%1
2634
21st to endNight
58%5%8%17%10%1
2644
February1st to 10thNight
59%5%11%16%7%1
2340
11th to 20thNight
56%5%12%18%8%1
2275
21st to endNight
58%5%11%16%9%1
1822
March1st to 10thNight
48%412%19%15%2
2064
11th to 20thNight
49%5%12%18%13%2
1980
21st to endNight
48%410%17%17%4
2178
April1st to 10thNight
51%5%10%19%14%2
1863
11th to 20thNight
47%37%25%17%2
1597
21st to endNight
54%310%16%15%3
1620
May1st to 10thNight
45%6%11%21%13%4
1620
11th to 20thNight
41%6%9%24%17%3
1452
21st to endNight
38%6%13%24%16%3
1479
June1st to 10thNight
42%7%11%24%14%3
1260
11th to 20thNight
37%6%11%24%20%2
1260
21st to endNight
40%7%13%23%15%2
1260
July1st to 10thNight
27%6%14%31%19%3
1225
11th to 20thNight
33%7%13%29%16%1
1218
21st to endNight
36%6%17%26%15%1
1568
August1st to 10thNight
35%8%18%27%11%1
1600
11th to 20thNight
35%7%15%29%12%2
1598
21st to endNight
40%6%15%26%12%1
1782
September1st to 10thNight
37%6%13%29%13%3
1788
11th to 20thNight
34%6%16%35%9%
1980
21st to endNight
44%6%15%28%9%
1980
October1st to 10thNight
47%5%12%22%13%
2131
11th to 20thNight
54%6%12%21%6%
2160
21st to endNight
60%5%11%16%7%1
2488
November1st to 10thNight
49%7%13%22%8%
2481
11th to 20thNight
58%7%12%16%7%
2660
21st to endNight
62%7%12%12%7%
2660
December1st to 10thNight
64%6%10%15%5%
2679
11th to 20thNight
59%5%12%14%7%2
3525
21st to endNight
72%5%10%9%4
5236

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
23%22%30%20%41
180
11th to 20thDay
22%16%36%19%7%
233
21st to endDay
25%15%32%19%8%1
264
February1st to 10thDay
28%26%30%12%4
240
11th to 20thDay
26%23%35%14%11
240
21st to endDay
33%26%32%9%
198
March1st to 10thDay
24%25%30%16%5%
335
11th to 20thDay
22%17%34%20%6%1
420
21st to endDay
26%17%33%18%5%1
462
April1st to 10thDay
25%16%30%21%8%1
420
11th to 20thDay
29%17%26%16%8%3
412
21st to endDay
30%17%29%15%8%1
420
May1st to 10thDay
21%14%37%18%7%3
423
11th to 20thDay
21%15%30%19%12%3
447
21st to endDay
18%12%35%23%10%2
553
June1st to 10thDay
16%15%38%24%6%
630
11th to 20thDay
17%16%36%23%7%2
630
21st to endDay
20%13%33%24%8%3
630
July1st to 10thDay
9%14%34%31%10%2
621
11th to 20thDay
12%12%34%27%11%4
618
21st to endDay
12%9%34%28%11%5%
579
August1st to 10thDay
17%7%25%29%16%5%
446
11th to 20thDay
13%5%31%28%14%9%
439
21st to endDay
16%11%29%24%14%6%
495
September1st to 10thDay
15%10%31%27%12%5%
450
11th to 20thDay
15%8%31%30%11%4
450
21st to endDay
25%14%24%24%11%3
450
October1st to 10thDay
22%14%29%22%11%3
450
11th to 20thDay
29%16%34%17%41
450
21st to endDay
32%20%31%15%21
379
November1st to 10thDay
29%17%38%12%5%
234
11th to 20thDay
26%24%32%14%31
180
21st to endDay
33%19%28%13%6%
180
December1st to 10thDay
26%16%36%16%7%
180
11th to 20thDay
29%22%30%17%11
180
21st to endDay
32%21%34%11%3
198
January1st to 10thNight
23%15%32%22%6%1
950
11th to 20thNight
26%16%28%23%7%1
926
21st to endNight
21%10%30%28%9%2
862
February1st to 10thNight
20%16%38%22%4
720
11th to 20thNight
20%15%35%24%6%1
703
21st to endNight
23%17%34%22%4
592
March1st to 10thNight
18%18%34%23%6%
720
11th to 20thNight
21%15%34%22%8%1
720
21st to endNight
21%11%33%28%7%1
792
April1st to 10thNight
25%11%33%25%6%
692
11th to 20thNight
23%13%26%25%11%2
533
21st to endNight
23%13%26%27%11%
540
May1st to 10thNight
15%9%27%36%12%1
540
11th to 20thNight
16%9%30%33%11%1
390
21st to endNight
12%8%31%33%14%1
389
June1st to 10thNight
17%6%34%33%10%
360
11th to 20thNight
15%7%26%39%13%1
360
21st to endNight
16%429%35%14%2
360
July1st to 10thNight
9%7%24%48%12%1
350
11th to 20thNight
8%426%41%20%
348
21st to endNight
11%6%23%41%19%1
572
August1st to 10thNight
12%324%37%22%2
537
11th to 20thNight
15%322%32%23%4
534
21st to endNight
16%7%22%30%23%2
594
September1st to 10thNight
16%6%27%30%18%2
688
11th to 20thNight
15%7%27%29%18%4
720
21st to endNight
21%8%26%24%17%3
720
October1st to 10thNight
26%9%25%28%11%2
720
11th to 20thNight
30%14%27%21%6%2
720
21st to endNight
32%15%27%21%31
792
November1st to 10thNight
26%14%29%24%7%
740
11th to 20thNight
27%17%27%23%6%
760
21st to endNight
31%16%30%18%5%
760
December1st to 10thNight
27%17%31%18%6%
779
11th to 20thNight
28%17%33%17%41
950
21st to endNight
31%16%28%20%6%
1045
Page generated at 2024-01-13 01:38:13. Version ac07

Copyright 2024 Attilla Danko


Killarney Provincial Park Observatory Clear Sky Chart |Charts Home