Puckett Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Puckett Observatory clear sky chart from 2005-11-05 to 2017-09-19.

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
47%
15462
21%
46965
15%
15419
54%
15419
25%
29929

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 15thNight
24%
720
20%
2327
9%
716
38%
716
16%
1569
January16th to endNight
26%
768
22%
2451
11%
768
39%
768
18%
1633
February1st to 15thNight
30%
704
22%
2112
10%
701
41%
701
22%
1361
February16th to endNight
21%
631
21%
1893
8%
631
32%
631
18%
1282
March1st to 15thNight
29%
720
20%
2078
11%
720
37%
720
21%
1405
March16th to endNight
37%
768
19%
2112
12%
768
43%
768
26%
1388
April1st to 15thNight
42%
610
24%
1868
15%
610
53%
610
30%
1097
April16th to endNight
47%
540
24%
1704
17%
540
55%
540
30%
1006
May1st to 15thNight
49%
540
18%
1620
11%
540
56%
540
26%
1037
May16th to endNight
65%
561
18%
1683
13%
561
67%
561
29%
1060
June1st to 15thNight
70%
540
15%
1620
13%
540
72%
540
30%
1023
June16th to endNight
77%
540
16%
1620
14%
540
78%
540
33%
991
July1st to 15thNight
71%
510
14%
1530
14%
510
71%
510
27%
987
July16th to endNight
75%
564
17%
1595
15%
531
75%
531
29%
1019
August1st to 15thNight
74%
539
19%
1639
19%
536
74%
536
29%
1044
August16th to endNight
65%
573
19%
1910
20%
573
67%
573
24%
1244
September1st to 15thNight
63%
689
17%
1949
16%
689
64%
689
25%
1317
September16th to endNight
61%
673
25%
1858
20%
673
64%
673
32%
1166
October1st to 15thNight
53%
660
34%
1818
25%
660
61%
660
36%
1072
October16th to endNight
47%
704
31%
2126
24%
704
57%
704
33%
1228
November1st to 15thNight
48%
700
29%
2276
24%
700
58%
700
32%
1255
November16th to endNight
36%
720
26%
2340
16%
720
48%
720
23%
1432
December1st to 15thNight
33%
720
20%
2340
14%
720
42%
720
19%
1555
December16th to endNight
29%
768
18%
2496
12%
768
37%
768
16%
1758

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%6%25%5%35%5%6%7%37%
47847
Night
12%5%2442445%7%43%
47163
TransparencyDay
43%7%11%17%15%3
47548
Night
38%6%11%19%18%4
46966
SeeingDay
17%8%19%21%19%13%
5339
Night
17%9%19%27%22%4
15464

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 15thDay
20%8%35%423345%38%
1611
16th to endDay
18%8%25%433335%41%
1770
February1st to 15thDay
18%8%35%5%2435%5%36%
1750
16th to endDay
20%7%25%43435%5%38%
1580
March1st to 15thDay
19%7%35%42445%7%36%
1881
16th to endDay
15%8%36%424446%39%
2111
April1st to 15thDay
13%6%24445%5%5%6%41%
2090
16th to endDay
13%5%25%5%36%446%42%
2256
May1st to 15thDay
13%436%6%35%45%7%39%
2331
16th to endDay
11%5%36%6%45%7%7%8%35%
2431
June1st to 15thDay
9%426%7%5%7%7%7%9%31%
2340
16th to endDay
6%4245%36%7%8%11%38%
2340
July1st to 15thDay
11%6%36%6%48%8%8%10%25%
2340
16th to endDay
9%5%36%6%6%9%8%7%10%24%
2465
August1st to 15thDay
8%5%16%6%47%8%10%10%28%
2307
16th to endDay
14%6%27%7%5%8%6%7%8%25%
2292
September1st to 15thDay
13%6%36%7%45%6%7%8%30%
1998
16th to endDay
15%5%26%42446%7%40%
1848
October1st to 15thDay
12%413322446%54%
1812
16th to endDay
13%5%2422333356%
1744
November1st to 15thDay
14%423313345%54%
1582
16th to endDay
18%6%24323346%44%
1620
December1st to 15thDay
21%8%35%33446%435%
1620
16th to endDay
25%9%3442334434%
1728
January1st to 15thNight
19%7%25%5%245%45%37%
2327
16th to endNight
18%7%25%5%3343440%
2451
February1st to 15thNight
16%6%24424346%42%
2103
16th to endNight
18%7%35%5%25%43438%
1893
March1st to 15thNight
14%6%35%5%245%5%6%40%
2078
16th to endNight
12%6%35%424437%44%
2112
April1st to 15thNight
13%323324449%48%
1868
16th to endNight
10%6%24424348%47%
1704
May1st to 15thNight
12%4346%25%5%6%7%43%
1619
16th to endNight
7%414435%6%7%10%43%
1682
June1st to 15thNight
6%4145%35%5%8%13%39%
1620
16th to endNight
43235%35%5%8%11%45%
1620
July1st to 15thNight
8%5%235%36%6%7%13%37%
1620
16th to endNight
5%4145%36%7%9%12%38%
1703
August1st to 15thNight
5%425%6%35%6%7%11%42%
1650
16th to endNight
9%6%26%5%35%5%7%10%36%
1910
September1st to 15thNight
8%5%25%6%35%5%6%9%39%
1949
16th to endNight
10%424425%45%7%48%
1858
October1st to 15thNight
11%413323435%56%
1818
16th to endNight
11%425%42223457%
2126
November1st to 15thNight
11%5%24322246%54%
2276
16th to endNight
16%5%24333335%47%
2340
December1st to 15thNight
18%7%35%42445%6%37%
2340
16th to endNight
24%9%25%5%23346%32%
2496

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 15thDay
47%47%15%20%4
1612
16th to endDay
45%37%19%18%5%
1770
February1st to 15thDay
48%46%18%18%2
1752
16th to endDay
47%47%18%17%3
1580
March1st to 15thDay
46%6%7%15%18%4
1881
16th to endDay
45%5%11%20%14%2
2112
April1st to 15thDay
41%7%11%19%16%3
2090
16th to endDay
41%5%9%21%17%4
2256
May1st to 15thDay
43%8%10%20%13%3
2331
16th to endDay
42%10%13%18%12%2
2435
June1st to 15thDay
44%10%15%20%7%1
2340
16th to endDay
34%12%16%21%13%2
2340
July1st to 15thDay
46%12%17%14%6%2
2201
16th to endDay
47%12%16%14%8%1
2310
August1st to 15thDay
42%13%16%17%8%1
2294
16th to endDay
52%10%13%13%8%1
2292
September1st to 15thDay
47%11%11%14%11%3
1998
16th to endDay
40%6%13%15%19%3
1848
October1st to 15thDay
31%6%8%17%27%7%
1812
16th to endDay
34%35%19%28%9%
1744
November1st to 15thDay
33%35%15%31%9%
1582
16th to endDay
40%45%16%25%6%
1620
December1st to 15thDay
48%5%7%16%16%5%
1620
16th to endDay
52%48%15%15%3
1728
January1st to 15thNight
47%47%16%19%4
2327
16th to endNight
46%47%17%19%5%
2451
February1st to 15thNight
43%38%18%20%5%
2112
16th to endNight
48%37%19%18%2
1893
March1st to 15thNight
43%6%8%17%17%6%
2078
16th to endNight
39%5%11%25%14%1
2112
April1st to 15thNight
32%5%12%23%21%4
1868
16th to endNight
35%411%24%19%5%
1704
May1st to 15thNight
38%7%14%21%16%1
1620
16th to endNight
32%11%16%23%12%2
1684
June1st to 15thNight
33%10%22%23%9%1
1620
16th to endNight
29%11%19%22%14%3
1620
July1st to 15thNight
34%12%20%20%11%1
1530
16th to endNight
32%12%21%20%10%2
1595
August1st to 15thNight
32%12%17%23%13%1
1639
16th to endNight
40%9%17%19%12%1
1910
September1st to 15thNight
38%11%14%17%14%3
1949
16th to endNight
33%8%11%22%19%4
1858
October1st to 15thNight
29%6%9%19%26%8%
1818
16th to endNight
32%4419%29%10%
2126
November1st to 15thNight
31%35%18%28%11%
2276
16th to endNight
40%35%18%24%7%
2340
December1st to 15thNight
45%5%9%15%17%6%
2340
16th to endNight
53%47%15%15%3
2496

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 15thDay
32%14%36%13%3
90
16th to endDay
23%34%32%7%2
96
February1st to 15thDay
32%24%38%4
90
16th to endDay
34%23%32%8%1
81
March1st to 15thDay
31%16%30%15%5%1
171
16th to endDay
19%15%29%22%11%1
288
April1st to 15thDay
20%12%26%22%14%3
270
16th to endDay
17%5%22%28%20%5%
270
May1st to 15thDay
18%12%25%16%14%12%
288
16th to endDay
13%7%16%29%17%16%
331
June1st to 15thDay
12%112%26%24%21%
315
16th to endDay
8%317%22%22%25%
315
July1st to 15thDay
15%111%21%23%26%
305
16th to endDay
10%26%19%28%32%
326
August1st to 15thDay
12%313%22%19%29%
313
16th to endDay
17%210%17%29%22%
332
September1st to 15thDay
15%412%19%29%18%
315
16th to endDay
16%311%29%29%9%
266
October1st to 15thDay
18%5%22%21%23%7%
255
16th to endDay
15%10%17%28%25%3
256
November1st to 15thDay
26%11%26%24%7%3
90
16th to endDay
26%13%27%25%6%
90
December1st to 15thDay
34%21%21%21%11
90
16th to endDay
41%14%33%9%1
96
January1st to 15thNight
27%18%25%21%6%
720
16th to endNight
26%14%26%26%4
768
February1st to 15thNight
24%15%25%29%4
704
16th to endNight
25%19%29%22%3
631
March1st to 15thNight
21%16%29%25%6%
720
16th to endNight
18%14%25%29%12%
768
April1st to 15thNight
15%13%24%31%12%1
610
16th to endNight
13%9%26%31%18%1
540
May1st to 15thNight
14%6%22%31%21%4
540
16th to endNight
10%114%31%33%7%
563
June1st to 15thNight
8%10%30%40%9%
540
16th to endNight
5%16%26%47%12%
540
July1st to 15thNight
10%15%25%45%12%
510
16th to endNight
7%15%20%50%15%
564
August1st to 15thNight
7%6%24%47%13%
539
16th to endNight
11%10%21%44%11%
573
September1st to 15thNight
12%210%25%40%8%
689
16th to endNight
12%215%33%32%3
673
October1st to 15thNight
13%7%21%28%23%6%
660
16th to endNight
13%9%23%27%22%3
704
November1st to 15thNight
15%10%21%28%19%5%
700
16th to endNight
22%14%24%24%13%
720
December1st to 15thNight
23%15%22%28%8%1
720
16th to endNight
31%11%23%25%7%
768
Page generated at 2017-09-20 04:49:55. Version ac04

Copyright 2017 A. Danko


Puckett Observatory Clear Sky Chart | Charts Home