East Kentucky Science Center
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the East Kentucky Science Center clear sky chart from 2005-11-06 to 2024-02-15.

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
42%
24050
18%
79847
14%
23947
48%
23947
21%
53420

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%
756
12%
4068
8%
737
29%
737
7%
3084
January11th to 20thNight
20%
760
19%
3992
8%
740
29%
740
8%
2782
January21st to endNight
20%
831
9%
4473
7%
814
31%
814
8%
3168
February1st to 10thNight
25%
760
15%
2432
8%
760
34%
760
16%
1731
February11th to 20thNight
17%
721
13%
2154
6%
719
24%
719
14%
1600
February21st to endNight
17%
592
16%
1776
7%
592
26%
592
13%
1342
March1st to 10thNight
28%
720
19%
2057
10%
720
36%
720
18%
1442
March11th to 20thNight
26%
720
16%
1980
8%
720
33%
720
19%
1418
March21st to endNight
31%
792
14%
2178
9%
792
35%
792
19%
1553
April1st to 10thNight
34%
720
19%
1980
10%
720
42%
720
25%
1302
April11th to 20thNight
41%
557
23%
1689
15%
557
49%
557
26%
1066
April21st to endNight
33%
540
20%
1620
9%
540
42%
540
23%
1091
May1st to 10thNight
40%
540
15%
1620
8%
540
44%
540
22%
1089
May11th to 20thNight
46%
531
15%
1592
10%
531
50%
531
23%
1080
May21st to endNight
60%
582
17%
1745
15%
582
63%
582
29%
1101
June1st to 10thNight
62%
540
17%
1620
15%
540
64%
540
31%
991
June11th to 20thNight
64%
540
16%
1620
13%
540
67%
540
32%
991
June21st to endNight
59%
540
18%
1620
15%
540
62%
540
30%
1003
July1st to 10thNight
64%
525
14%
1575
13%
525
65%
525
28%
1017
July11th to 20thNight
71%
522
17%
1566
16%
522
73%
522
33%
953
July21st to endNight
67%
591
18%
1672
17%
558
68%
558
29%
1052
August1st to 10thNight
70%
537
21%
1600
18%
534
70%
534
31%
983
August11th to 20thNight
68%
534
20%
1598
18%
534
69%
534
30%
1020
August21st to endNight
71%
602
25%
1869
24%
602
71%
602
34%
1088
September1st to 10thNight
64%
720
22%
1980
18%
720
65%
720
33%
1243
September11th to 20thNight
61%
720
25%
1980
20%
720
63%
720
32%
1256
September21st to endNight
55%
720
27%
1980
20%
720
61%
720
34%
1223
October1st to 10thNight
58%
720
27%
2016
24%
720
61%
720
37%
1204
October11th to 20thNight
45%
720
25%
2160
21%
720
53%
720
29%
1341
October21st to endNight
39%
792
26%
2376
20%
792
48%
792
26%
1529
November1st to 10thNight
48%
740
27%
2386
24%
740
56%
740
29%
1401
November11th to 20thNight
37%
760
24%
2470
17%
760
48%
760
23%
1547
November21st to endNight
41%
760
23%
2470
18%
760
50%
760
23%
1561
December1st to 10thNight
25%
760
14%
2470
9%
760
32%
760
13%
1821
December11th to 20thNight
29%
759
18%
2987
11%
759
38%
759
13%
2094
December21st to endNight
26%
826
10%
4476
9%
817
35%
817
8%
3253

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
15%9%36%6%35%5%5%7%36%
78700
Night
15%9%36%5%3445%7%37%
80393
TransparencyDay
47%5%11%21%13%2
78423
Night
46%5%10%21%14%3
80189
SeeingDay
21%12%24%22%15%7%
13906
Night
20%10%22%29%17%2
24073

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
15%17%9%9%6%3445%6%23%
2836
11th to 20thDay
18%15%8%11%8%4333423%
2840
21st to endDay
21%18%47%5%34445%25%
3124
February1st to 10thDay
18%14%5%8%5%34446%30%
1744
11th to 20thDay
24%10%47%5%34445%30%
1788
21st to endDay
23%12%46%5%34445%29%
1480
March1st to 10thDay
18%10%45%4245%46%38%
1903
11th to 20thDay
20%9%47%5%35%5%5%6%31%
1980
21st to endDay
20%9%36%5%35%45%5%34%
2178
April1st to 10thDay
14%8%46%6%35%5%5%7%39%
1980
11th to 20thDay
15%6%37%5%34447%42%
2234
21st to endDay
17%7%37%5%35%5%5%7%37%
2340
May1st to 10thDay
16%7%27%7%445%6%7%33%
2340
11th to 20thDay
16%8%37%6%46%6%5%7%33%
2301
21st to endDay
10%5%26%7%46%6%7%10%38%
2531
June1st to 10thDay
11%5%36%5%46%5%6%8%40%
2340
11th to 20thDay
8%5%26%7%47%6%6%9%39%
2340
21st to endDay
9%5%36%5%35%6%8%9%39%
2340
July1st to 10thDay
11%5%35%7%35%7%7%9%38%
2340
11th to 20thDay
9%5%36%6%36%7%8%11%35%
2340
21st to endDay
11%6%37%7%46%6%6%10%34%
2547
August1st to 10thDay
11%6%27%6%36%7%8%11%34%
2327
11th to 20thDay
12%7%26%6%47%6%7%9%34%
2303
21st to endDay
10%425%6%5%6%6%7%10%40%
2465
September1st to 10thDay
12%6%24426%5%7%8%44%
1980
11th to 20thDay
12%5%26%5%345%6%7%44%
1980
21st to endDay
18%6%35%5%23445%46%
1980
October1st to 10thDay
13%5%245%345%5%7%49%
1942
11th to 20thDay
16%5%25%33335%6%49%
1800
21st to endDay
21%7%25%423347%42%
1980
November1st to 10thDay
12%6%2432445%5%52%
1690
11th to 20thDay
14%8%36%6%24446%42%
1710
21st to endDay
16%9%46%42435%6%40%
1710
December1st to 10thDay
24%11%47%5%35%45%6%27%
1710
11th to 20thDay
18%14%37%5%34446%33%
2153
21st to endDay
17%15%48%7%46%5%6%6%22%
3124
January1st to 10thNight
16%18%6%9%6%35%44423%
4109
11th to 20thNight
21%13%49%6%2334429%
4120
21st to endNight
23%12%5%8%6%34345%28%
4532
February1st to 10thNight
18%10%5%7%7%34446%31%
2432
11th to 20thNight
23%11%47%5%3445%5%29%
2153
21st to endNight
23%12%47%5%35%445%28%
1776
March1st to 10thNight
18%10%36%5%44445%38%
2057
11th to 20thNight
20%8%36%5%345%5%7%33%
1980
21st to endNight
15%8%37%7%45%5%5%7%34%
2178
April1st to 10thNight
14%6%35%6%3445%8%41%
1980
11th to 20thNight
15%7%25%43446%8%43%
1689
21st to endNight
15%8%35%5%45%447%40%
1620
May1st to 10thNight
18%7%35%5%35%46%8%37%
1620
11th to 20thNight
14%6%36%5%36%6%7%8%36%
1592
21st to endNight
8%5%35%6%35%5%6%10%42%
1744
June1st to 10thNight
9%5%23446%6%8%10%43%
1620
11th to 20thNight
5%5%35%5%35%6%8%10%44%
1620
21st to endNight
10%425%5%36%6%6%10%42%
1620
July1st to 10thNight
10%6%27%6%45%5%7%9%40%
1620
11th to 20thNight
6%4245%45%6%9%11%45%
1620
21st to endNight
10%426%5%37%6%7%9%42%
1771
August1st to 10thNight
8%5%245%46%6%7%11%43%
1611
11th to 20thNight
9%6%35%6%36%6%7%10%40%
1598
21st to endNight
9%424425%6%7%9%48%
1869
September1st to 10thNight
11%425%435%5%6%8%46%
1980
11th to 20thNight
12%427%5%34447%48%
1980
21st to endNight
11%6%25%5%245%46%49%
1980
October1st to 10thNight
13%4244335%5%7%52%
2016
11th to 20thNight
16%6%25%5%23346%47%
2160
21st to endNight
20%7%25%423446%43%
2376
November1st to 10thNight
14%5%34434345%52%
2386
11th to 20thNight
15%7%36%434446%43%
2470
21st to endNight
14%10%245%3445%6%42%
2470
December1st to 10thNight
21%14%5%7%434445%28%
2470
11th to 20thNight
18%12%6%7%43445%6%32%
3042
21st to endNight
19%15%48%7%45%46%6%22%
4532

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
62%48%17%9%1
2837
11th to 20thDay
68%27%16%6%1
2840
21st to endDay
62%36%22%6%1
3124
February1st to 10thDay
57%38%20%11%1
1744
11th to 20thDay
58%47%19%11%2
1798
21st to endDay
57%48%16%12%3
1480
March1st to 10thDay
48%49%22%15%2
1903
11th to 20thDay
54%49%18%12%3
1980
21st to endDay
51%5%9%24%10%2
2178
April1st to 10thDay
44%5%10%23%15%4
1980
11th to 20thDay
43%49%21%19%5%
2234
21st to endDay
47%5%11%23%11%3
2340
May1st to 10thDay
48%6%12%22%11%2
2340
11th to 20thDay
50%7%12%21%9%1
2305
21st to endDay
39%8%16%24%12%1
2531
June1st to 10thDay
40%7%12%24%15%1
2340
11th to 20thDay
40%9%13%19%17%2
2340
21st to endDay
38%9%14%21%16%3
2340
July1st to 10thDay
41%9%16%19%15%1
2275
11th to 20thDay
39%8%16%21%13%3
2271
21st to endDay
44%8%13%24%10%1
2405
August1st to 10thDay
41%10%18%20%10%
2314
11th to 20thDay
45%8%14%23%10%1
2303
21st to endDay
38%8%14%22%15%3
2465
September1st to 10thDay
38%7%11%23%16%5%
1980
11th to 20thDay
38%5%10%27%17%2
1980
21st to endDay
42%49%23%21%2
1980
October1st to 10thDay
35%6%12%24%20%4
1942
11th to 20thDay
38%311%25%21%3
1800
21st to endDay
44%38%27%15%3
1980
November1st to 10thDay
33%49%24%26%3
1690
11th to 20thDay
44%37%23%19%4
1710
21st to endDay
46%39%22%18%2
1710
December1st to 10thDay
59%410%19%7%1
1710
11th to 20thDay
54%39%17%15%1
2150
21st to endDay
60%5%10%20%5%
3124
January1st to 10thNight
64%48%15%8%1
4109
11th to 20thNight
57%46%19%12%2
4120
21st to endNight
59%38%20%9%1
4532
February1st to 10thNight
55%310%20%11%1
2432
11th to 20thNight
58%38%17%11%2
2154
21st to endNight
59%49%15%10%3
1776
March1st to 10thNight
51%37%17%19%3
2057
11th to 20thNight
51%5%10%22%11%1
1980
21st to endNight
50%5%11%19%13%2
2178
April1st to 10thNight
42%5%10%23%18%3
1980
11th to 20thNight
40%5%10%22%17%7%
1689
21st to endNight
45%6%10%24%13%2
1620
May1st to 10thNight
46%6%13%21%11%3
1620
11th to 20thNight
44%8%14%22%11%2
1593
21st to endNight
37%8%16%23%15%1
1745
June1st to 10thNight
33%9%17%22%17%3
1620
11th to 20thNight
32%9%18%20%19%3
1620
21st to endNight
35%8%15%23%14%5%
1620
July1st to 10thNight
40%7%14%20%16%3
1575
11th to 20thNight
31%9%17%23%16%4
1566
21st to endNight
36%8%16%26%12%2
1672
August1st to 10thNight
34%8%16%26%14%2
1600
11th to 20thNight
37%8%17%24%13%1
1598
21st to endNight
30%8%13%27%19%4
1869
September1st to 10thNight
34%7%13%23%16%7%
1980
11th to 20thNight
36%7%10%22%22%3
1980
21st to endNight
34%6%10%25%23%2
1980
October1st to 10thNight
33%5%11%25%21%6%
2016
11th to 20thNight
39%48%24%21%4
2160
21st to endNight
43%47%23%19%4
2376
November1st to 10thNight
36%47%22%24%6%
2386
11th to 20thNight
42%48%20%20%6%
2470
21st to endNight
43%48%27%16%2
2470
December1st to 10thNight
58%48%19%9%2
2470
11th to 20thNight
55%37%22%11%1
3044
21st to endNight
60%5%9%17%9%
4532

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
28%23%31%14%31
270
11th to 20thDay
39%23%25%12%1
270
21st to endDay
30%26%28%13%21
297
February1st to 10thDay
28%20%34%13%5%
270
11th to 20thDay
47%20%27%6%
252
21st to endDay
38%20%30%11%1
198
March1st to 10thDay
30%20%31%15%5%
343
11th to 20thDay
28%21%28%18%41
420
21st to endDay
29%18%29%18%6%
462
April1st to 10thDay
27%17%25%19%10%1
420
11th to 20thDay
21%20%27%18%11%3
412
21st to endDay
26%14%31%19%8%2
420
May1st to 10thDay
23%17%29%17%10%4
423
11th to 20thDay
17%11%28%26%13%5%
447
21st to endDay
14%5%25%24%22%10%
485
June1st to 10thDay
14%6%22%27%22%9%
450
11th to 20thDay
12%8%19%30%22%10%
450
21st to endDay
13%426%26%19%12%
450
July1st to 10thDay
16%317%23%19%22%
445
11th to 20thDay
8%5%19%29%24%16%
444
21st to endDay
14%5%17%30%23%13%
488
August1st to 10thDay
15%417%25%27%13%
446
11th to 20thDay
14%6%13%28%27%12%
439
21st to endDay
13%313%27%30%14%
495
September1st to 10thDay
15%314%23%32%13%
450
11th to 20thDay
14%313%27%27%15%
450
21st to endDay
20%9%19%27%18%8%
450
October1st to 10thDay
15%8%22%25%22%8%
450
11th to 20thDay
18%11%26%27%15%4
450
21st to endDay
26%14%22%25%12%2
495
November1st to 10thDay
19%13%29%25%11%3
288
11th to 20thDay
25%15%28%19%12%1
270
21st to endDay
24%17%28%21%9%1
270
December1st to 10thDay
32%19%26%17%5%1
270
11th to 20thDay
28%18%29%19%43
270
21st to endDay
30%18%34%12%5%1
297
January1st to 10thNight
28%18%28%21%5%
760
11th to 20thNight
32%16%27%21%4
760
21st to endNight
25%17%31%24%2
836
February1st to 10thNight
26%14%30%28%2
760
11th to 20thNight
34%17%30%19%1
722
21st to endNight
34%17%29%19%2
592
March1st to 10thNight
28%15%26%27%5%
720
11th to 20thNight
26%15%29%22%8%
720
21st to endNight
20%14%30%28%8%
792
April1st to 10thNight
20%15%27%29%9%
720
11th to 20thNight
20%11%24%29%14%1
557
21st to endNight
19%10%33%30%8%1
540
May1st to 10thNight
21%8%26%31%12%2
540
11th to 20thNight
16%7%23%33%19%2
531
21st to endNight
10%416%34%30%6%
584
June1st to 10thNight
11%317%36%29%4
540
11th to 20thNight
8%315%38%31%6%
540
21st to endNight
10%219%36%29%4
540
July1st to 10thNight
14%210%31%36%7%
525
11th to 20thNight
8%211%33%41%6%
522
21st to endNight
10%410%33%35%8%
591
August1st to 10thNight
9%29%33%41%5%
537
11th to 20thNight
12%29%31%38%8%
534
21st to endNight
11%17%32%41%8%
602
September1st to 10thNight
13%311%29%39%6%
720
11th to 20thNight
14%213%27%39%5%
720
21st to endNight
14%5%19%29%31%3
720
October1st to 10thNight
15%417%30%29%4
720
11th to 20thNight
20%8%21%32%17%2
720
21st to endNight
23%9%23%30%13%1
792
November1st to 10thNight
16%8%22%33%18%2
740
11th to 20thNight
19%13%25%30%11%1
760
21st to endNight
21%11%21%35%11%1
760
December1st to 10thNight
30%15%24%26%5%
760
11th to 20thNight
25%12%28%28%6%1
760
21st to endNight
31%14%22%29%5%
836
Page generated at 2024-02-12 06:35:33. Version ac07

Copyright 2024 Attilla Danko


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