Possum Poop Hollow Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Possum Poop Hollow 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
37%
23898
16%
74946
12%
23849
43%
23849
19%
52219

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%
757
13%
2459
6%
757
26%
757
9%
1924
January11th to 20thNight
15%
744
9%
2417
4%
744
23%
744
9%
1957
January21st to endNight
17%
792
13%
2574
6%
792
26%
792
11%
1993
February1st to 10thNight
21%
720
11%
2340
7%
720
27%
720
12%
1784
February11th to 20thNight
14%
701
10%
2230
5%
700
20%
700
11%
1725
February21st to endNight
14%
592
15%
1763
5%
592
24%
592
12%
1346
March1st to 10thNight
25%
720
19%
1980
9%
720
35%
720
19%
1404
March11th to 20thNight
23%
720
16%
1980
8%
720
30%
720
17%
1456
March21st to endNight
23%
792
16%
2178
7%
792
32%
792
18%
1584
April1st to 10thNight
27%
720
16%
1926
7%
720
34%
720
21%
1379
April11th to 20thNight
31%
682
20%
1746
8%
682
38%
682
28%
1182
April21st to endNight
34%
540
21%
1620
10%
540
42%
540
22%
1083
May1st to 10thNight
38%
540
15%
1620
7%
540
43%
540
19%
1139
May11th to 20thNight
38%
531
14%
1592
7%
531
43%
531
21%
1120
May21st to endNight
53%
582
16%
1745
12%
582
57%
582
28%
1126
June1st to 10thNight
56%
473
18%
1553
16%
473
60%
473
28%
949
June11th to 20thNight
52%
360
16%
1440
19%
360
57%
360
22%
877
June21st to endNight
56%
539
16%
1619
14%
539
58%
539
29%
1020
July1st to 10thNight
58%
525
14%
1575
13%
525
60%
525
26%
1044
July11th to 20thNight
64%
522
16%
1566
13%
522
66%
522
31%
976
July21st to endNight
61%
591
17%
1672
15%
558
63%
558
28%
1050
August1st to 10thNight
62%
537
17%
1600
14%
534
63%
534
28%
1030
August11th to 20thNight
63%
534
20%
1598
15%
534
65%
534
27%
1030
August21st to endNight
64%
684
23%
1872
17%
684
66%
684
35%
1150
September1st to 10thNight
60%
720
22%
1858
14%
720
62%
720
33%
1212
September11th to 20thNight
61%
720
26%
1980
21%
720
64%
720
37%
1190
September21st to endNight
50%
720
24%
1980
18%
720
56%
720
29%
1296
October1st to 10thNight
51%
720
21%
2125
20%
720
56%
720
30%
1312
October11th to 20thNight
41%
720
22%
2160
17%
720
49%
720
27%
1379
October21st to endNight
35%
792
23%
2376
18%
792
45%
792
22%
1612
November1st to 10thNight
44%
740
24%
2292
20%
740
51%
740
27%
1417
November11th to 20thNight
29%
760
20%
2470
13%
760
40%
760
18%
1699
November21st to endNight
31%
760
17%
2620
12%
760
39%
760
16%
1843
December1st to 10thNight
19%
760
11%
2660
6%
760
25%
760
10%
2054
December11th to 20thNight
23%
759
10%
3242
8%
759
28%
759
9%
2411
December21st to endNight
23%
829
9%
4518
7%
817
31%
817
7%
3466

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
18%9%46%5%35%5%5%7%33%
74531
Night
18%10%46%5%3445%6%35%
75241
TransparencyDay
50%411%21%12%2
74252
Night
50%5%10%20%13%2
75039
SeeingDay
24%13%25%22%12%5%
13731
Night
23%10%24%28%14%2
23913

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
18%15%8%9%8%35%436%21%
1706
11th to 20thDay
23%18%6%10%5%34345%20%
1671
21st to endDay
21%19%8%8%6%3333422%
1782
February1st to 10thDay
23%14%5%9%7%34345%24%
1620
11th to 20thDay
21%15%5%11%5%3445%6%23%
1614
21st to endDay
22%14%48%5%24335%27%
1491
March1st to 10thDay
17%12%5%7%5%23446%35%
1980
11th to 20thDay
21%12%45%5%35%45%5%31%
1980
21st to endDay
21%11%46%6%3445%7%29%
2178
April1st to 10thDay
17%10%46%7%4445%6%33%
2033
11th to 20thDay
18%8%25%5%35%45%7%38%
2177
21st to endDay
22%7%36%4345%5%8%33%
2340
May1st to 10thDay
20%7%36%6%45%5%5%7%30%
2340
11th to 20thDay
22%7%36%5%36%45%7%31%
2301
21st to endDay
13%5%25%6%36%6%7%9%38%
2531
June1st to 10thDay
15%5%26%5%46%5%6%9%37%
2394
11th to 20thDay
14%5%25%6%46%6%6%8%37%
2507
21st to endDay
15%5%245%46%6%7%9%37%
2340
July1st to 10thDay
13%5%36%6%45%6%7%8%36%
2340
11th to 20thDay
13%5%35%5%46%6%7%9%37%
2340
21st to endDay
15%6%36%6%46%6%6%9%34%
2547
August1st to 10thDay
12%6%27%6%46%7%8%11%32%
2327
11th to 20thDay
14%6%26%5%35%6%7%10%34%
2303
21st to endDay
12%6%25%5%445%6%9%41%
2466
September1st to 10thDay
16%5%244245%6%6%46%
2098
11th to 20thDay
13%5%345%45%46%8%45%
1980
21st to endDay
19%7%35%5%3445%6%39%
1980
October1st to 10thDay
17%6%35%43445%8%42%
1834
11th to 20thDay
19%7%25%5%3445%6%39%
1800
21st to endDay
24%7%25%5%33345%38%
1980
November1st to 10thDay
14%7%24434446%47%
1781
11th to 20thDay
17%11%46%5%245%6%6%34%
1710
21st to endDay
19%12%5%6%43445%6%33%
1556
December1st to 10thDay
26%14%7%8%5%34435%21%
1520
11th to 20thDay
23%16%7%7%5%23335%26%
1910
21st to endDay
23%19%5%7%5%35%45%7%17%
3074
January1st to 10thNight
19%16%6%9%7%3444423%
2459
11th to 20thNight
24%15%7%9%7%3343421%
2417
21st to endNight
20%17%6%8%6%3434425%
2574
February1st to 10thNight
22%13%5%8%7%24445%25%
2340
11th to 20thNight
23%13%48%6%45%45%424%
2228
21st to endNight
24%15%5%6%5%2445%427%
1763
March1st to 10thNight
18%10%46%5%25%445%36%
1980
11th to 20thNight
22%10%47%5%34346%33%
1980
21st to endNight
22%9%45%5%44445%33%
2178
April1st to 10thNight
20%10%45%5%3435%7%35%
1926
11th to 20thNight
17%7%35%43445%9%39%
1746
21st to endNight
17%6%36%435%45%6%40%
1620
May1st to 10thNight
19%7%35%6%45%5%6%8%33%
1620
11th to 20thNight
19%7%36%5%26%46%8%34%
1592
21st to endNight
11%6%35%5%45%45%8%43%
1744
June1st to 10thNight
12%5%24445%6%6%8%45%
1553
11th to 20thNight
10%5%26%5%35%6%7%10%39%
1440
21st to endNight
14%425%4445%6%9%43%
1619
July1st to 10thNight
11%6%37%5%36%5%7%8%39%
1620
11th to 20thNight
10%426%5%35%5%6%10%43%
1620
21st to endNight
12%425%5%46%6%7%9%40%
1771
August1st to 10thNight
9%5%26%6%36%6%7%9%39%
1611
11th to 20thNight
12%6%25%6%46%46%8%41%
1598
21st to endNight
11%5%24425%45%8%48%
1872
September1st to 10thNight
12%5%36%5%3445%7%47%
1858
11th to 20thNight
11%42443345%7%52%
1980
21st to endNight
16%6%35%5%34447%44%
1980
October1st to 10thNight
15%5%25%43445%7%46%
2125
11th to 20thNight
16%6%25%44445%7%43%
2160
21st to endNight
24%6%24434445%40%
2376
November1st to 10thNight
13%7%35%42445%5%47%
2292
11th to 20thNight
19%11%35%5%245%47%34%
2470
21st to endNight
19%11%47%6%34446%33%
2620
December1st to 10thNight
23%15%6%9%5%3434423%
2660
11th to 20thNight
20%16%6%7%6%34335%26%
3285
21st to endNight
22%17%6%8%6%44445%21%
4564

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
68%38%15%5%1
1707
11th to 20thDay
68%39%14%5%
1671
21st to endDay
68%28%13%7%1
1782
February1st to 10thDay
66%38%17%5%1
1620
11th to 20thDay
64%48%17%7%1
1623
21st to endDay
61%48%17%9%1
1491
March1st to 10thDay
51%38%24%11%1
1980
11th to 20thDay
55%48%21%11%2
1980
21st to endDay
57%47%19%11%2
2178
April1st to 10thDay
52%49%18%13%3
2033
11th to 20thDay
46%411%18%19%3
2177
21st to endDay
50%411%21%12%2
2340
May1st to 10thDay
53%5%10%21%10%1
2340
11th to 20thDay
53%413%18%10%2
2305
21st to endDay
42%7%16%23%10%1
2531
June1st to 10thDay
43%6%14%22%14%1
2394
11th to 20thDay
44%7%13%21%13%1
2507
21st to endDay
42%6%14%24%13%2
2340
July1st to 10thDay
43%7%14%19%15%3
2275
11th to 20thDay
41%7%11%23%15%2
2271
21st to endDay
46%5%11%23%13%2
2405
August1st to 10thDay
44%6%15%25%10%1
2314
11th to 20thDay
43%6%13%26%11%1
2303
21st to endDay
40%6%13%25%13%3
2466
September1st to 10thDay
37%5%11%22%22%3
2098
11th to 20thDay
38%5%9%27%17%3
1980
21st to endDay
46%39%21%19%1
1980
October1st to 10thDay
42%412%23%17%2
1834
11th to 20thDay
46%49%25%15%
1800
21st to endDay
50%37%23%15%2
1980
November1st to 10thDay
40%310%26%17%4
1781
11th to 20thDay
49%49%19%16%3
1710
21st to endDay
54%39%20%13%
1556
December1st to 10thDay
67%38%16%41
1520
11th to 20thDay
63%29%18%7%1
1906
21st to endDay
68%312%13%4
3074
January1st to 10thNight
66%37%14%8%1
2459
11th to 20thNight
69%39%13%5%
2417
21st to endNight
64%38%17%5%2
2574
February1st to 10thNight
62%410%17%8%
2340
11th to 20thNight
64%38%17%9%
2230
21st to endNight
61%39%15%9%3
1763
March1st to 10thNight
51%38%25%12%2
1980
11th to 20thNight
54%410%19%12%1
1980
21st to endNight
53%48%19%12%4
2178
April1st to 10thNight
50%49%20%14%2
1926
11th to 20thNight
43%312%20%16%5%
1746
21st to endNight
45%5%10%22%16%2
1620
May1st to 10thNight
50%6%11%18%12%3
1620
11th to 20thNight
48%7%12%18%13%2
1593
21st to endNight
39%6%16%25%12%1
1745
June1st to 10thNight
36%7%12%27%16%2
1553
11th to 20thNight
39%8%14%22%15%3
1440
21st to endNight
36%8%15%23%16%2
1619
July1st to 10thNight
41%8%13%21%15%2
1575
11th to 20thNight
35%8%13%24%17%3
1566
21st to endNight
37%8%14%24%17%1
1672
August1st to 10thNight
39%7%16%24%13%1
1600
11th to 20thNight
40%7%13%23%16%1
1598
21st to endNight
34%6%13%28%16%4
1872
September1st to 10thNight
38%5%13%18%21%5%
1858
11th to 20thNight
32%6%12%26%22%3
1980
21st to endNight
41%5%11%21%21%1
1980
October1st to 10thNight
38%412%25%17%3
2125
11th to 20thNight
41%49%25%19%2
2160
21st to endNight
48%36%24%17%2
2376
November1st to 10thNight
40%410%20%20%6%
2292
11th to 20thNight
51%37%19%16%3
2470
21st to endNight
55%39%20%12%1
2620
December1st to 10thNight
65%38%17%5%1
2660
11th to 20thNight
63%310%17%8%
3288
21st to endNight
66%49%15%6%
4564

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
30%30%26%10%6%
270
11th to 20thDay
40%22%29%8%
257
21st to endDay
39%26%25%7%21
264
February1st to 10thDay
38%22%32%7%2
240
11th to 20thDay
46%25%23%6%
240
21st to endDay
39%23%30%7%
209
March1st to 10thDay
32%19%29%16%4
420
11th to 20thDay
31%22%27%14%5%1
420
21st to endDay
33%16%31%15%5%
462
April1st to 10thDay
28%21%23%20%6%1
420
11th to 20thDay
26%17%26%17%9%4
412
21st to endDay
30%18%26%18%7%2
420
May1st to 10thDay
27%18%25%16%9%5%
423
11th to 20thDay
23%12%28%23%10%3
447
21st to endDay
16%8%25%27%16%8%
485
June1st to 10thDay
18%7%22%31%17%6%
450
11th to 20thDay
19%7%24%27%18%6%
450
21st to endDay
16%7%29%30%14%4
450
July1st to 10thDay
16%5%18%25%21%15%
445
11th to 20thDay
13%423%32%20%9%
444
21st to endDay
19%5%20%26%21%9%
488
August1st to 10thDay
13%421%30%20%12%
446
11th to 20thDay
15%6%19%28%20%11%
439
21st to endDay
13%321%31%20%12%
495
September1st to 10thDay
16%6%18%28%22%10%
450
11th to 20thDay
12%315%31%28%11%
450
21st to endDay
22%8%22%28%14%5%
450
October1st to 10thDay
18%9%25%23%19%6%
450
11th to 20thDay
20%14%28%24%12%1
450
21st to endDay
29%16%24%20%10%1
495
November1st to 10thDay
20%12%29%26%10%3
379
11th to 20thDay
30%18%28%18%6%1
270
21st to endDay
28%19%35%14%31
196
December1st to 10thDay
33%24%26%11%5%1
180
11th to 20thDay
38%19%22%16%5%
180
21st to endDay
38%19%26%12%5%
285
January1st to 10thNight
32%18%26%19%4
760
11th to 20thNight
34%16%27%20%2
744
21st to endNight
29%19%31%19%2
792
February1st to 10thNight
32%13%29%24%2
720
11th to 20thNight
33%19%31%16%1
703
21st to endNight
34%16%31%16%2
592
March1st to 10thNight
27%15%29%26%3
720
11th to 20thNight
32%15%28%18%6%1
720
21st to endNight
28%12%33%23%41
792
April1st to 10thNight
28%14%28%24%7%
720
11th to 20thNight
21%14%30%22%12%1
682
21st to endNight
18%11%31%31%9%1
540
May1st to 10thNight
23%8%26%31%11%1
540
11th to 20thNight
21%5%27%31%14%1
531
21st to endNight
14%323%33%24%4
584
June1st to 10thNight
13%323%37%23%1
473
11th to 20thNight
13%423%36%23%1
360
21st to endNight
16%418%40%22%1
539
July1st to 10thNight
14%216%36%28%4
525
11th to 20thNight
10%314%38%31%5%
522
21st to endNight
14%312%36%31%4
591
August1st to 10thNight
10%213%39%34%3
537
11th to 20thNight
14%311%38%29%5%
534
21st to endNight
13%313%33%33%6%
684
September1st to 10thNight
14%315%34%29%5%
720
11th to 20thNight
13%318%30%33%4
720
21st to endNight
18%6%20%33%22%3
720
October1st to 10thNight
18%5%20%30%23%4
720
11th to 20thNight
19%10%26%32%12%1
720
21st to endNight
27%9%23%29%11%1
792
November1st to 10thNight
17%9%25%32%16%
740
11th to 20thNight
29%11%26%24%9%1
760
21st to endNight
27%11%25%28%8%1
760
December1st to 10thNight
33%16%27%20%4
760
11th to 20thNight
28%17%27%24%5%
760
21st to endNight
31%13%26%28%2
836
Page generated at 2024-01-13 19:28:28. Version ac07

Copyright 2024 Attilla Danko


Possum Poop Hollow Observatory Clear Sky Chart |Charts Home