Bouse
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Bouse clear sky chart from 2005-11-05 to 2018-02-13.

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
78%
16457
39%
48779
34%
16418
83%
16418
62%
21816

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
74%
779
35%
2522
35%
776
79%
776
50%
1181
January16th to endNight
71%
832
40%
2675
39%
832
78%
832
50%
1254
February1st to 15thNight
75%
746
40%
2254
37%
746
83%
746
59%
1014
February16th to endNight
68%
632
36%
1895
37%
632
73%
632
50%
933
March1st to 15thNight
70%
720
39%
2054
33%
720
80%
720
61%
945
March16th to endNight
73%
768
39%
2112
31%
768
79%
768
59%
1014
April1st to 15thNight
66%
719
35%
1912
20%
719
74%
719
61%
922
April16th to endNight
72%
612
46%
1692
29%
612
82%
612
78%
695
May1st to 15thNight
74%
539
42%
1619
30%
539
81%
539
72%
648
May16th to endNight
78%
561
40%
1684
30%
561
84%
561
74%
671
June1st to 15thNight
85%
540
36%
1620
31%
540
86%
540
76%
628
June16th to endNight
92%
540
37%
1620
33%
540
92%
540
82%
605
July1st to 15thNight
90%
510
30%
1530
26%
510
90%
510
61%
686
July16th to endNight
82%
564
32%
1593
27%
531
83%
531
48%
799
August1st to 15thNight
89%
555
38%
1627
30%
552
90%
552
63%
736
August16th to endNight
87%
764
41%
1910
31%
764
87%
764
62%
977
September1st to 15thNight
84%
720
36%
1974
30%
720
86%
720
62%
945
September16th to endNight
86%
716
47%
1980
40%
716
90%
716
78%
835
October1st to 15thNight
81%
720
43%
1985
36%
720
85%
720
71%
882
October16th to endNight
85%
768
47%
2304
44%
768
89%
768
72%
940
November1st to 15thNight
82%
760
38%
2443
39%
760
86%
760
61%
1031
November16th to endNight
80%
780
43%
2535
44%
780
85%
780
61%
1067
December1st to 15thNight
76%
780
38%
2535
38%
780
81%
780
54%
1134
December16th to endNight
72%
832
39%
2704
39%
832
78%
832
49%
1274

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
212212335%73%
49260
Night
2112212235%73%
48977
TransparencyDay
14%1311%24%44%
48955
Night
14%1311%24%44%
48783
SeeingDay
3316%33%30%12%
6114
Night
3111%36%40%7%
16467

By Month

Percentage Cloud Cover SW (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
3314212236%68%
1746
16th to endDay
5%212212336%67%
1898
February1st to 15thDay
3212213337%69%
1872
16th to endDay
421332235%5%64%
1579
March1st to 15thDay
311111345%73%
1905
16th to endDay
1112212235%74%
2112
April1st to 15thDay
222213436%71%
2035
16th to endDay
1111225%83%
2268
May1st to 15thDay
111123481%
2331
16th to endDay
1111121483%
2429
June1st to 15thDay
111111387%
2340
16th to endDay
112386%
2340
July1st to 15thDay
1112213347%69%
2340
16th to endDay
4213335%5%6%8%55%
2467
August1st to 15thDay
11242445%7%64%
2322
16th to endDay
3212313346%67%
2292
September1st to 15thDay
2213323345%68%
1985
16th to endDay
1121222382%
1980
October1st to 15thDay
2111222479%
1974
16th to endDay
111222479%
1920
November1st to 15thDay
1212212236%74%
1743
16th to endDay
2112111336%73%
1755
December1st to 15thDay
3213423246%65%
1755
16th to endDay
4313322346%63%
1872
January1st to 15thNight
331232244466%
2522
16th to endNight
5%313213235%67%
2675
February1st to 15thNight
2213222245%71%
2245
16th to endNight
5%212323446%63%
1895
March1st to 15thNight
2212113345%71%
2054
16th to endNight
2112223346%70%
2112
April1st to 15thNight
1112212335%72%
1912
16th to endNight
111122384%
1692
May1st to 15thNight
111111235%80%
1619
16th to endNight
1111222383%
1684
June1st to 15thNight
111112483%
1620
16th to endNight
1112287%
1620
July1st to 15thNight
1131245%7%69%
1620
16th to endNight
22234345%5%9%56%
1701
August1st to 15thNight
1112222447%70%
1636
16th to endNight
2112313446%68%
1910
September1st to 15thNight
1112323345%70%
1974
16th to endNight
1111112384%
1980
October1st to 15thNight
12212235%78%
1985
16th to endNight
1211213480%
2304
November1st to 15thNight
1212222235%73%
2443
16th to endNight
221221222476%
2535
December1st to 15thNight
332212346%67%
2535
16th to endNight
5%212323335%66%
2704

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
19%1414%34%25%
1747
16th to endDay
19%15%15%28%28%
1898
February1st to 15thDay
16%1413%28%34%
1872
16th to endDay
20%2415%30%27%
1579
March1st to 15thDay
13%1210%31%40%
1905
16th to endDay
15%211%30%38%
2112
April1st to 15thDay
13%1210%29%42%
2035
16th to endDay
6%28%28%53%
2268
May1st to 15thDay
8%127%26%53%
2331
16th to endDay
8%16%21%61%
2432
June1st to 15thDay
7%316%72%
2340
16th to endDay
7%127%80%
2340
July1st to 15thDay
14%35%10%17%48%
2201
16th to endDay
22%6%9%19%20%22%
2312
August1st to 15thDay
17%4414%23%35%
2307
16th to endDay
17%3411%28%35%
2292
September1st to 15thDay
20%2412%20%40%
1985
16th to endDay
8%11418%65%
1980
October1st to 15thDay
10%127%24%52%
1974
16th to endDay
9%138%22%54%
1920
November1st to 15thDay
12%1313%30%39%
1743
16th to endDay
13%1311%30%40%
1755
December1st to 15thDay
20%15%17%26%29%
1755
16th to endDay
20%16%20%31%19%
1872
January1st to 15thNight
20%2412%27%32%
2522
16th to endNight
21%1314%25%33%
2675
February1st to 15thNight
16%1314%25%38%
2256
16th to endNight
21%2412%25%33%
1895
March1st to 15thNight
14%1210%26%43%
2054
16th to endNight
16%2311%27%39%
2112
April1st to 15thNight
16%128%28%42%
1912
16th to endNight
6%128%26%55%
1692
May1st to 15thNight
8%117%25%55%
1620
16th to endNight
8%17%23%58%
1685
June1st to 15thNight
8%1315%71%
1620
16th to endNight
5%128%80%
1620
July1st to 15thNight
13%36%12%16%48%
1530
16th to endNight
20%5%7%21%19%25%
1593
August1st to 15thNight
13%2313%28%38%
1627
16th to endNight
15%3412%26%37%
1910
September1st to 15thNight
14%35%14%23%38%
1974
16th to endNight
7%115%17%67%
1980
October1st to 15thNight
10%128%22%53%
1985
16th to endNight
10%28%18%59%
2304
November1st to 15thNight
14%1210%27%44%
2443
16th to endNight
14%129%28%43%
2535
December1st to 15thNight
17%2413%28%33%
2535
16th to endNight
21%1417%28%24%
2704

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
11%21%31%25%8%
135
16th to endDay
4420%21%32%15%
170
February1st to 15thDay
45%19%32%28%10%
315
16th to endDay
9%7%24%37%16%4
238
March1st to 15thDay
49%18%32%27%7%
270
16th to endDay
110%26%30%21%10%
288
April1st to 15thDay
5%9%27%28%17%11%
269
16th to endDay
213%30%32%16%5%
270
May1st to 15thDay
26%21%38%22%8%
288
16th to endDay
2423%38%24%7%
330
June1st to 15thDay
2216%41%29%8%
315
16th to endDay
8%40%33%15%
315
July1st to 15thDay
1440%37%14%
305
16th to endDay
3325%44%22%
327
August1st to 15thDay
25%34%40%17%
315
16th to endDay
2331%44%18%
332
September1st to 15thDay
312%34%37%11%
315
16th to endDay
2116%34%33%11%
315
October1st to 15thDay
2419%37%28%8%
309
16th to endDay
12420%41%29%
144
November1st to 15thDay
227%31%42%13%
135
16th to endDay
4121%34%24%14%
135
December1st to 15thDay
1116%30%40%10%
135
16th to endDay
4314%30%34%11%
144
January1st to 15thNight
5%12%39%34%7%
780
16th to endNight
6%112%41%32%5%
832
February1st to 15thNight
3212%41%34%5%
752
16th to endNight
7%216%45%23%5%
632
March1st to 15thNight
3317%37%30%6%
720
16th to endNight
2315%38%32%6%
768
April1st to 15thNight
2422%38%27%5%
719
16th to endNight
1420%41%27%4
612
May1st to 15thNight
2317%39%33%4
540
16th to endNight
1115%42%34%4
563
June1st to 15thNight
119%47%37%3
540
16th to endNight
437%50%5%
540
July1st to 15thNight
1226%63%4
510
16th to endNight
3219%64%9%
564
August1st to 15thNight
1321%65%8%
555
16th to endNight
3322%57%13%
764
September1st to 15thNight
25%26%53%11%
720
16th to endNight
29%30%48%8%
716
October1st to 15thNight
2111%39%41%4
720
16th to endNight
117%34%42%12%
768
November1st to 15thNight
29%43%35%8%
760
16th to endNight
310%36%39%9%
780
December1st to 15thNight
4111%43%35%4
780
16th to endNight
6%213%41%31%6%
832
Page generated at 2018-02-13 18:46:01. Version ac04

Copyright 2018 A. Danko


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