Hanceville
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Hanceville clear sky chart from 2005-11-05 to 2017-09-23.

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
49%
15270
23%
47037
17%
15227
56%
15227
28%
28869

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
25%
720
23%
2327
9%
716
42%
716
21%
1477
January16th to endNight
25%
768
25%
2328
11%
768
38%
768
21%
1533
February1st to 15thNight
28%
704
25%
2112
9%
701
43%
701
26%
1317
February16th to endNight
28%
631
24%
1893
11%
631
39%
631
25%
1207
March1st to 15thNight
30%
720
20%
2154
10%
720
38%
720
23%
1395
March16th to endNight
38%
705
23%
2049
14%
705
45%
705
28%
1267
April1st to 15thNight
40%
539
24%
1797
16%
539
52%
539
30%
1027
April16th to endNight
46%
540
27%
1800
19%
540
58%
540
32%
999
May1st to 15thNight
51%
540
21%
1632
13%
540
58%
540
29%
1024
May16th to endNight
68%
561
23%
1682
18%
561
72%
561
35%
995
June1st to 15thNight
74%
540
18%
1620
15%
540
76%
540
34%
975
June16th to endNight
76%
540
19%
1620
17%
540
77%
540
37%
948
July1st to 15thNight
73%
510
13%
1530
12%
510
74%
510
29%
980
July16th to endNight
74%
564
16%
1611
16%
531
76%
531
30%
1022
August1st to 15thNight
79%
539
19%
1788
22%
536
80%
536
32%
1042
August16th to endNight
72%
573
20%
1910
24%
573
72%
573
24%
1230
September1st to 15thNight
62%
615
19%
1875
18%
615
64%
615
25%
1231
September16th to endNight
67%
689
28%
1903
23%
689
70%
689
37%
1130
October1st to 15thNight
55%
660
34%
1815
26%
660
61%
660
38%
1064
October16th to endNight
52%
704
33%
2139
28%
704
60%
704
36%
1208
November1st to 15thNight
49%
700
30%
2276
24%
700
60%
700
35%
1240
November16th to endNight
40%
720
27%
2340
18%
720
53%
720
28%
1388
December1st to 15thNight
34%
720
23%
2340
15%
720
45%
720
22%
1491
December16th to endNight
28%
768
20%
2496
14%
768
37%
768
19%
1679

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
13%5%25%5%35%5%5%7%40%
47860
Night
12%5%2442445%7%46%
47238
TransparencyDay
41%6%11%19%17%4
47563
Night
36%6%10%20%19%6%
47039
SeeingDay
16%6%19%23%22%12%
5179
Night
15%7%22%28%21%4
15272

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
21%7%24423335%41%
1611
16th to endDay
18%7%24323225%46%
1895
February1st to 15thDay
17%9%34423435%41%
1750
16th to endDay
19%7%2442434441%
1580
March1st to 15thDay
19%7%25%5%24345%38%
1804
16th to endDay
14%6%35%6%2445%7%40%
2183
April1st to 15thDay
13%5%25%424446%45%
2151
16th to endDay
10%5%25%435%5%5%6%45%
2160
May1st to 15thDay
12%5%25%435%45%7%42%
2316
16th to endDay
10%426%6%35%6%6%7%39%
2431
June1st to 15thDay
7%425%7%47%6%8%8%36%
2340
16th to endDay
6%225%5%37%5%7%10%42%
2340
July1st to 15thDay
10%436%6%47%7%7%11%30%
2340
16th to endDay
6%435%6%5%8%9%9%10%30%
2446
August1st to 15thDay
7%426%6%5%7%7%8%10%33%
2160
16th to endDay
11%7%38%6%46%5%7%9%29%
2292
September1st to 15thDay
12%5%25%6%36%6%5%7%36%
2073
16th to endDay
12%4245%2446%6%46%
1894
October1st to 15thDay
9%42432445%6%50%
1815
16th to endDay
12%41331233458%
1729
November1st to 15thDay
12%5%13413235%54%
1582
16th to endDay
16%6%13423445%47%
1620
December1st to 15thDay
21%7%35%424345%38%
1620
16th to endDay
24%8%34424235%35%
1728
January1st to 15thNight
18%6%3442444443%
2327
16th to endNight
17%7%35%424345%40%
2328
February1st to 15thNight
18%6%14323336%46%
2103
16th to endNight
17%425%414345%45%
1893
March1st to 15thNight
17%5%25%5%24346%42%
2154
16th to endNight
12%6%244135%5%6%47%
2049
April1st to 15thNight
13%41342435%7%49%
1797
16th to endNight
10%424323447%52%
1800
May1st to 15thNight
9%5%25%5%25%5%5%7%46%
1631
16th to endNight
5%3235%36%5%6%9%49%
1682
June1st to 15thNight
5%313436%6%7%11%45%
1620
16th to endNight
5%223425%5%7%11%48%
1620
July1st to 15thNight
7%4245%46%6%7%10%40%
1620
16th to endNight
5%425%5%36%6%9%12%39%
1720
August1st to 15thNight
42145%346%8%13%44%
1800
16th to endNight
8%5%35%5%35%5%7%9%39%
1910
September1st to 15thNight
8%5%246%35%6%5%7%42%
1875
16th to endNight
8%42443446%6%51%
1903
October1st to 15thNight
9%413423345%56%
1815
16th to endNight
13%5%2331222458%
2139
November1st to 15thNight
11%423323345%56%
2276
16th to endNight
14%5%24424335%49%
2340
December1st to 15thNight
16%6%345%23346%42%
2340
16th to endNight
22%7%25%423345%37%
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
46%36%16%22%4
1612
16th to endDay
42%35%22%20%5%
1895
February1st to 15thDay
44%47%22%17%3
1752
16th to endDay
45%38%15%22%4
1580
March1st to 15thDay
47%48%15%18%5%
1804
16th to endDay
42%5%11%21%16%2
2184
April1st to 15thDay
38%410%20%17%6%
2151
16th to endDay
37%5%10%22%20%3
2160
May1st to 15thDay
40%7%10%19%16%4
2316
16th to endDay
40%7%13%24%12%1
2435
June1st to 15thDay
40%10%14%19%13%1
2340
16th to endDay
34%9%14%22%14%4
2340
July1st to 15thDay
40%12%18%18%7%2
2201
16th to endDay
40%13%18%18%7%
2292
August1st to 15thDay
40%12%16%18%10%2
2148
16th to endDay
48%9%12%18%8%2
2292
September1st to 15thDay
43%8%14%17%11%4
2073
16th to endDay
36%6%11%20%19%5%
1894
October1st to 15thDay
32%5%9%18%24%9%
1815
16th to endDay
30%3418%31%10%
1729
November1st to 15thDay
33%26%18%29%9%
1582
16th to endDay
38%46%17%25%8%
1620
December1st to 15thDay
47%5%7%17%17%5%
1620
16th to endDay
53%28%18%13%3
1728
January1st to 15thNight
43%37%17%23%4
2327
16th to endNight
45%36%17%20%6%
2328
February1st to 15thNight
41%27%21%20%6%
2112
16th to endNight
41%36%20%23%4
1893
March1st to 15thNight
42%49%18%18%6%
2154
16th to endNight
35%6%9%25%19%3
2049
April1st to 15thNight
34%410%23%18%8%
1797
16th to endNight
31%5%8%24%23%6%
1800
May1st to 15thNight
36%7%12%17%22%4
1632
16th to endNight
27%9%15%27%13%5%
1684
June1st to 15thNight
29%10%17%23%18%1
1620
16th to endNight
27%8%17%22%20%3
1620
July1st to 15thNight
34%10%21%20%8%4
1530
16th to endNight
33%10%20%20%13%
1611
August1st to 15thNight
27%12%18%24%14%3
1788
16th to endNight
37%10%15%20%11%3
1910
September1st to 15thNight
38%10%15%17%13%5%
1875
16th to endNight
31%5%10%21%23%7%
1903
October1st to 15thNight
30%5%7%20%23%12%
1815
16th to endNight
32%2314%33%14%
2139
November1st to 15thNight
30%36%18%26%14%
2276
16th to endNight
37%36%16%25%10%
2340
December1st to 15thNight
43%47%18%20%5%
2340
16th to endNight
48%38%18%15%5%
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
25%18%32%17%32
90
16th to endDay
29%21%39%6%3
96
February1st to 15thDay
26%26%34%11%1
90
16th to endDay
30%16%40%11%1
81
March1st to 15thDay
27%22%37%6%6%
94
16th to endDay
19%9%32%24%12%
288
April1st to 15thDay
20%9%29%22%15%3
270
16th to endDay
12%8%25%27%22%2
270
May1st to 15thDay
18%5%27%25%14%9%
288
16th to endDay
15%419%25%18%15%
331
June1st to 15thDay
12%9%26%28%21%
315
16th to endDay
9%113%24%22%27%
315
July1st to 15thDay
9%11%24%31%21%
305
16th to endDay
8%6%18%35%30%
326
August1st to 15thDay
13%110%20%30%23%
313
16th to endDay
17%17%23%33%16%
332
September1st to 15thDay
14%213%19%32%18%
315
16th to endDay
13%211%28%32%10%
283
October1st to 15thDay
13%323%32%20%5%
255
16th to endDay
17%418%31%23%3
156
November1st to 15thDay
24%15%24%23%11%1
90
16th to endDay
15%16%34%22%8%2
90
December1st to 15thDay
25%21%35%14%21
90
16th to endDay
34%14%31%14%41
96
January1st to 15thNight
23%15%33%20%6%
720
16th to endNight
21%15%34%24%3
768
February1st to 15thNight
21%12%33%27%4
704
16th to endNight
21%13%33%27%3
631
March1st to 15thNight
21%13%32%27%5%
720
16th to endNight
16%12%29%26%14%
705
April1st to 15thNight
15%7%34%25%14%2
539
16th to endNight
12%7%29%32%16%1
540
May1st to 15thNight
11%425%30%25%3
540
16th to endNight
6%114%38%33%4
563
June1st to 15thNight
6%19%34%37%11%
540
16th to endNight
5%8%26%46%12%
540
July1st to 15thNight
9%6%27%42%13%
510
16th to endNight
7%6%23%44%17%
564
August1st to 15thNight
6%428%47%13%
539
16th to endNight
10%15%30%41%10%
573
September1st to 15thNight
11%211%26%38%9%
615
16th to endNight
9%114%36%34%4
689
October1st to 15thNight
12%323%29%25%5%
660
16th to endNight
15%8%19%30%24%2
704
November1st to 15thNight
13%8%25%29%19%3
700
16th to endNight
19%10%26%29%13%
720
December1st to 15thNight
22%10%27%29%9%
720
16th to endNight
27%10%29%24%8%
768
Page generated at 2017-09-24 08:15:57. Version ac04

Copyright 2017 A. Danko


Hanceville Clear Sky Chart | Charts Home