Troy Space Gazebo
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Troy Space Gazebo clear sky chart from 2005-11-06 to 2024-01-12.

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%
24009
15%
74853
10%
23956
42%
23956
20%
52028

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%
947
12%
2648
5%
946
25%
946
13%
2049
January11th to 20thNight
18%
906
8%
2535
3%
906
22%
906
11%
2048
January21st to endNight
22%
798
10%
2580
5%
798
27%
798
12%
1977
February1st to 10thNight
17%
720
8%
2340
2%
720
23%
720
10%
1839
February11th to 20thNight
21%
700
13%
2163
6%
699
28%
699
13%
1630
February21st to endNight
15%
592
15%
1776
4%
592
28%
592
15%
1304
March1st to 10thNight
26%
720
16%
2110
10%
720
32%
720
18%
1502
March11th to 20thNight
26%
720
21%
1980
9%
720
36%
720
22%
1361
March21st to endNight
29%
792
17%
2178
8%
792
36%
792
18%
1584
April1st to 10thNight
28%
638
15%
1898
7%
638
36%
638
20%
1299
April11th to 20thNight
31%
533
21%
1615
9%
533
41%
533
22%
1100
April21st to endNight
36%
540
19%
1620
7%
540
46%
540
24%
1080
May1st to 10thNight
38%
540
13%
1620
9%
540
42%
540
21%
1128
May11th to 20thNight
41%
531
18%
1592
11%
531
49%
531
24%
1045
May21st to endNight
54%
583
15%
1745
11%
582
60%
582
31%
1060
June1st to 10thNight
52%
413
18%
1337
16%
413
58%
413
30%
789
June11th to 20thNight
54%
360
20%
1260
21%
360
61%
360
27%
736
June21st to endNight
55%
442
21%
1342
18%
442
62%
442
33%
801
July1st to 10thNight
63%
525
17%
1400
14%
525
67%
525
40%
822
July11th to 20thNight
62%
522
21%
1392
16%
522
67%
522
40%
827
July21st to endNight
64%
591
18%
1643
13%
558
68%
558
38%
965
August1st to 10thNight
65%
537
20%
1600
16%
534
68%
534
36%
918
August11th to 20thNight
62%
534
23%
1598
18%
534
67%
534
34%
939
August21st to endNight
61%
594
24%
1782
16%
594
66%
594
36%
1030
September1st to 10thNight
56%
656
19%
1916
14%
656
59%
656
30%
1188
September11th to 20thNight
60%
720
28%
1980
21%
720
63%
720
38%
1169
September21st to endNight
51%
720
23%
1980
17%
720
56%
720
31%
1277
October1st to 10thNight
45%
720
21%
2040
16%
720
50%
720
29%
1307
October11th to 20thNight
32%
720
16%
2160
8%
720
42%
720
19%
1514
October21st to endNight
26%
792
15%
2506
11%
792
33%
792
16%
1808
November1st to 10thNight
36%
740
22%
2406
16%
740
46%
740
24%
1502
November11th to 20thNight
25%
760
16%
2470
9%
760
36%
760
17%
1717
November21st to endNight
23%
760
14%
2606
9%
760
30%
760
14%
1875
December1st to 10thNight
18%
760
9%
2660
4%
760
24%
760
10%
2069
December11th to 20thNight
18%
845
9%
3380
3%
843
26%
843
9%
2485
December21st to endNight
15%
1038
4%
4995
2%
1026
20%
1026
5%
4284

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
14%9%47%6%45%5%6%8%33%
74614
Night
15%10%47%6%345%5%7%35%
75085
TransparencyDay
48%7%12%20%12%1
74324
Night
48%6%12%21%12%1
74896
SeeingDay
17%12%29%23%13%6%
14211
Night
19%10%29%29%12%1
24023

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%14%5%10%9%46%5%46%21%
1517
11th to 20thDay
16%14%7%12%9%5%5%6%5%6%16%
1448
21st to endDay
15%17%8%10%7%5%6%5%5%5%16%
1772
February1st to 10thDay
15%14%6%10%10%6%6%45%5%20%
1620
11th to 20thDay
14%12%5%12%8%5%5%5%5%6%24%
1682
21st to endDay
15%15%5%10%8%35%446%25%
1480
March1st to 10thDay
15%11%47%7%46%5%6%7%28%
1849
11th to 20thDay
13%11%5%7%8%345%48%31%
1980
21st to endDay
19%11%49%8%35%45%5%27%
2178
April1st to 10thDay
15%11%5%7%6%35%46%8%30%
2078
11th to 20thDay
16%9%47%6%445%5%8%33%
2293
21st to endDay
18%8%47%6%35%45%7%33%
2340
May1st to 10thDay
17%7%37%6%45%5%6%7%33%
2340
11th to 20thDay
18%8%37%5%35%5%5%7%34%
2301
21st to endDay
12%5%35%5%35%6%6%10%40%
2531
June1st to 10thDay
10%5%36%7%45%5%6%9%41%
2613
11th to 20thDay
11%5%36%6%46%5%5%9%41%
2700
21st to endDay
10%5%36%5%36%7%7%10%37%
2609
July1st to 10thDay
7%436%6%46%7%6%8%45%
2520
11th to 20thDay
9%5%345%46%6%7%10%42%
2520
21st to endDay
7%5%25%6%47%7%8%9%40%
2576
August1st to 10thDay
8%6%25%6%46%7%7%10%40%
2327
11th to 20thDay
9%426%7%47%7%8%9%38%
2303
21st to endDay
10%6%26%6%45%5%6%9%41%
2570
September1st to 10thDay
12%6%36%6%45%5%6%9%38%
2026
11th to 20thDay
11%5%25%5%35%5%7%9%44%
1980
21st to endDay
13%6%36%6%45%6%6%9%36%
1980
October1st to 10thDay
13%7%26%5%445%6%7%41%
1919
11th to 20thDay
17%11%36%6%445%48%32%
1800
21st to endDay
20%11%37%6%35%45%6%29%
1847
November1st to 10thDay
11%9%46%6%45%5%6%7%38%
1672
11th to 20thDay
14%10%47%7%46%5%5%6%31%
1710
21st to endDay
19%11%48%7%35%446%30%
1571
December1st to 10thDay
14%15%7%11%8%46%5%45%22%
1520
11th to 20thDay
17%15%6%9%6%35%5%5%6%24%
1778
21st to endDay
26%20%7%9%6%44445%11%
2664
January1st to 10thNight
17%11%5%9%7%45%45%6%25%
2648
11th to 20thNight
18%15%5%10%9%35%445%21%
2535
21st to endNight
12%14%7%11%8%45%5%5%5%24%
2580
February1st to 10thNight
15%16%6%8%9%5%6%45%5%23%
2340
11th to 20thNight
14%13%5%9%9%45%6%5%6%26%
2163
21st to endNight
19%12%48%5%345%46%30%
1776
March1st to 10thNight
15%10%47%7%445%5%7%33%
2110
11th to 20thNight
13%8%46%5%35%6%5%6%39%
1980
21st to endNight
17%9%47%6%35%445%34%
2178
April1st to 10thNight
16%8%46%5%445%6%6%36%
1898
11th to 20thNight
18%7%35%5%345%47%39%
1615
21st to endNight
17%8%25%5%3445%7%40%
1620
May1st to 10thNight
16%8%37%6%346%5%8%34%
1620
11th to 20thNight
18%6%35%4245%5%8%40%
1592
21st to endNight
9%5%25%435%6%5%9%46%
1744
June1st to 10thNight
11%5%35%5%35%45%8%47%
1337
11th to 20thNight
9%5%245%445%6%8%46%
1260
21st to endNight
9%6%35%5%245%5%8%49%
1342
July1st to 10thNight
6%5%235%25%5%6%9%53%
1440
11th to 20thNight
8%4234245%5%9%53%
1440
21st to endNight
5%424435%6%7%10%49%
1740
August1st to 10thNight
7%4245%345%6%10%50%
1611
11th to 20thNight
6%425%5%445%7%9%49%
1598
21st to endNight
9%425%43445%7%53%
1782
September1st to 10thNight
9%6%35%5%3446%8%47%
1916
11th to 20thNight
10%5%243335%5%7%53%
1980
21st to endNight
14%5%36%43445%7%45%
1980
October1st to 10thNight
14%7%35%42345%7%45%
2040
11th to 20thNight
18%9%36%6%35%5%46%36%
2160
21st to endNight
22%9%46%6%35%5%5%5%31%
2506
November1st to 10thNight
13%7%35%5%345%5%7%43%
2406
11th to 20thNight
16%9%47%6%46%5%6%6%31%
2470
21st to endNight
19%12%5%7%6%245%5%6%29%
2606
December1st to 10thNight
17%14%6%9%7%45%5%5%6%22%
2660
11th to 20thNight
14%14%5%9%7%45%45%7%25%
3414
21st to endNight
28%22%6%9%5%3434413%
4998

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%7%11%13%7%1
1518
11th to 20thDay
68%7%13%8%5%
1448
21st to endDay
69%5%8%11%6%1
1772
February1st to 10thDay
65%7%9%13%6%
1620
11th to 20thDay
61%5%9%16%8%1
1691
21st to endDay
59%6%10%16%8%2
1480
March1st to 10thDay
55%7%13%17%7%1
1849
11th to 20thDay
51%6%10%19%12%3
1980
21st to endDay
59%5%9%18%7%1
2178
April1st to 10thDay
52%5%12%19%12%1
2078
11th to 20thDay
49%5%12%19%13%2
2293
21st to endDay
50%6%13%16%13%2
2340
May1st to 10thDay
49%7%11%20%10%2
2340
11th to 20thDay
48%6%11%18%14%2
2305
21st to endDay
40%8%14%23%15%2
2531
June1st to 10thDay
39%6%12%26%14%2
2613
11th to 20thDay
39%7%13%23%16%3
2700
21st to endDay
39%8%13%22%16%2
2609
July1st to 10thDay
35%7%11%25%19%4
2451
11th to 20thDay
34%9%14%24%18%2
2445
21st to endDay
36%9%14%21%17%3
2433
August1st to 10thDay
36%9%14%27%13%1
2314
11th to 20thDay
38%9%13%24%13%2
2303
21st to endDay
39%7%12%24%17%1
2570
September1st to 10thDay
41%7%14%23%13%2
2026
11th to 20thDay
34%7%13%33%14%
1980
21st to endDay
42%6%14%24%12%1
1980
October1st to 10thDay
41%7%12%26%13%2
1919
11th to 20thDay
50%6%14%19%10%
1800
21st to endDay
56%5%13%18%8%
1847
November1st to 10thDay
44%7%12%23%12%1
1672
11th to 20thDay
52%5%13%19%10%1
1710
21st to endDay
57%5%12%18%7%1
1571
December1st to 10thDay
63%5%10%16%5%
1520
11th to 20thDay
60%6%13%15%6%
1774
21st to endDay
75%6%9%6%3
2664
January1st to 10thNight
60%5%10%17%7%1
2648
11th to 20thNight
66%5%12%12%5%
2535
21st to endNight
61%6%11%16%6%1
2580
February1st to 10thNight
63%6%10%13%7%1
2340
11th to 20thNight
57%7%10%16%9%1
2165
21st to endNight
55%5%11%18%9%1
1776
March1st to 10thNight
51%6%11%21%10%1
2110
11th to 20thNight
44%7%11%21%15%2
1980
21st to endNight
53%5%8%22%11%1
2178
April1st to 10thNight
48%5%11%21%14%2
1898
11th to 20thNight
45%7%10%18%18%2
1615
21st to endNight
44%5%11%20%16%3
1620
May1st to 10thNight
47%7%11%20%12%2
1620
11th to 20thNight
42%6%10%19%19%3
1593
21st to endNight
33%8%15%24%17%3
1745
June1st to 10thNight
36%5%11%28%17%2
1337
11th to 20thNight
35%7%14%24%18%2
1260
21st to endNight
32%7%12%26%21%1
1342
July1st to 10thNight
28%6%11%29%22%4
1400
11th to 20thNight
29%6%13%32%18%3
1392
21st to endNight
27%9%18%23%19%4
1643
August1st to 10thNight
28%8%15%32%15%2
1600
11th to 20thNight
30%8%14%32%13%3
1598
21st to endNight
30%6%15%29%19%2
1782
September1st to 10thNight
35%7%13%27%16%2
1916
11th to 20thNight
30%6%12%31%20%1
1980
21st to endNight
38%5%12%31%13%1
1980
October1st to 10thNight
39%5%11%25%19%1
2040
11th to 20thNight
48%7%12%20%13%1
2160
21st to endNight
53%6%11%20%9%1
2506
November1st to 10thNight
40%6%12%26%15%1
2406
11th to 20thNight
50%6%14%20%9%1
2470
21st to endNight
55%5%14%19%7%
2606
December1st to 10thNight
62%7%10%15%6%
2660
11th to 20thNight
57%7%14%14%7%1
3417
21st to endNight
75%5%10%7%2
4998

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%21%34%15%7%
270
11th to 20thDay
22%16%41%16%31
243
21st to endDay
23%14%41%16%5%1
264
February1st to 10thDay
24%21%40%13%2
240
11th to 20thDay
22%20%41%14%2
240
21st to endDay
22%24%41%10%2
198
March1st to 10thDay
25%20%36%15%4
289
11th to 20thDay
21%15%35%22%6%1
420
21st to endDay
28%15%30%21%5%1
462
April1st to 10thDay
17%17%36%20%9%1
420
11th to 20thDay
25%17%29%14%9%6%
412
21st to endDay
25%13%31%19%10%3
420
May1st to 10thDay
24%11%30%22%11%3
423
11th to 20thDay
21%11%28%22%11%6%
447
21st to endDay
14%7%23%28%19%9%
485
June1st to 10thDay
13%10%30%30%13%4
602
11th to 20thDay
12%8%31%31%15%3
630
21st to endDay
12%7%30%31%15%5%
630
July1st to 10thDay
6%5%22%31%23%11%
621
11th to 20thDay
11%6%25%33%17%8%
618
21st to endDay
8%5%25%27%24%10%
517
August1st to 10thDay
9%222%25%28%13%
446
11th to 20thDay
11%419%29%21%15%
439
21st to endDay
12%5%22%28%21%12%
495
September1st to 10thDay
13%425%23%23%11%
450
11th to 20thDay
11%321%25%25%15%
450
21st to endDay
16%9%24%24%19%8%
450
October1st to 10thDay
17%10%26%20%17%10%
450
11th to 20thDay
22%16%30%24%7%1
450
21st to endDay
27%15%37%16%41
362
November1st to 10thDay
16%19%35%21%7%2
270
11th to 20thDay
20%22%34%16%7%1
270
21st to endDay
23%19%35%19%4
203
December1st to 10thDay
23%19%37%12%8%
180
11th to 20thDay
28%21%35%13%31
180
21st to endDay
26%24%33%14%3
265
January1st to 10thNight
22%15%35%22%6%1
950
11th to 20thNight
25%15%33%23%41
906
21st to endNight
19%13%33%29%6%
798
February1st to 10thNight
22%14%38%22%3
720
11th to 20thNight
21%15%32%26%5%
703
21st to endNight
25%16%37%19%2
592
March1st to 10thNight
20%13%35%27%6%
720
11th to 20thNight
17%14%38%25%5%1
720
21st to endNight
22%13%30%27%8%1
792
April1st to 10thNight
21%13%33%29%4
638
11th to 20thNight
21%9%34%26%8%2
533
21st to endNight
21%7%31%31%9%
540
May1st to 10thNight
18%7%30%34%10%1
540
11th to 20thNight
22%5%26%32%15%1
531
21st to endNight
11%225%41%20%2
584
June1st to 10thNight
13%5%25%42%15%
413
11th to 20thNight
11%324%50%12%
360
21st to endNight
11%321%45%18%1
442
July1st to 10thNight
8%219%40%27%4
525
11th to 20thNight
9%419%41%25%3
522
21st to endNight
5%321%47%22%2
591
August1st to 10thNight
9%218%37%32%3
537
11th to 20thNight
8%219%36%31%4
534
21st to endNight
10%318%35%31%3
594
September1st to 10thNight
13%5%18%35%24%5%
656
11th to 20thNight
11%417%34%27%6%
720
21st to endNight
17%5%20%31%22%5%
720
October1st to 10thNight
17%7%25%31%17%3
720
11th to 20thNight
24%11%29%27%8%2
720
21st to endNight
26%12%30%27%5%
792
November1st to 10thNight
17%11%31%26%14%1
740
11th to 20thNight
21%16%31%24%7%1
760
21st to endNight
25%13%33%22%6%
760
December1st to 10thNight
25%12%36%21%6%
760
11th to 20thNight
23%14%37%22%3
845
21st to endNight
30%12%33%21%3
1045
Page generated at 2024-01-08 22:31:28. Version ac07

Copyright 2024 Attilla Danko


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