Colorado Springs
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Colorado Springs clear sky chart from 2005-11-05 to 2017-08-12.

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
56%
15786
28%
46501
19%
15745
65%
15745
43%
24920

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
52%
898
31%
2506
19%
895
63%
895
50%
1289
January16th to endNight
53%
795
35%
2523
24%
795
66%
795
48%
1218
February1st to 15thNight
41%
700
26%
2220
15%
699
55%
699
41%
1162
February16th to endNight
41%
632
35%
1894
15%
632
62%
632
47%
962
March1st to 15thNight
48%
720
29%
2124
16%
720
58%
720
46%
1110
March16th to endNight
47%
672
28%
2016
16%
672
59%
672
41%
1085
April1st to 15thNight
42%
539
25%
1798
14%
539
59%
539
38%
932
April16th to endNight
45%
540
23%
1800
18%
540
57%
540
32%
1012
May1st to 15thNight
51%
539
20%
1656
17%
539
57%
539
31%
991
May16th to endNight
54%
562
18%
1498
12%
561
60%
561
37%
903
June1st to 15thNight
63%
540
22%
1440
16%
540
68%
540
48%
771
June16th to endNight
72%
540
23%
1440
18%
540
75%
540
45%
798
July1st to 15thNight
71%
510
17%
1360
15%
510
73%
510
32%
864
July16th to endNight
78%
564
20%
1458
19%
531
77%
531
35%
900
August1st to 15thNight
74%
527
15%
1659
17%
524
74%
524
29%
1008
August16th to endNight
79%
525
22%
1750
24%
525
80%
525
35%
960
September1st to 15thNight
70%
495
27%
1650
28%
495
74%
495
35%
921
September16th to endNight
73%
492
35%
1779
36%
492
79%
492
47%
796
October1st to 15thNight
57%
632
31%
1952
20%
632
65%
632
43%
1023
October16th to endNight
63%
729
36%
2137
22%
729
71%
729
53%
1060
November1st to 15thNight
60%
875
36%
2275
20%
875
67%
875
60%
1152
November16th to endNight
57%
900
38%
2358
22%
900
66%
900
58%
1186
December1st to 15thNight
46%
900
27%
2520
13%
900
57%
900
47%
1348
December16th to endNight
43%
960
29%
2688
14%
960
55%
960
43%
1469

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
44244245%6%8%53%
47485
Night
331332345%7%59%
46677
Cloud CoverDay
44234245%6%8%54%
47483
Night
331332345%7%59%
46677
TransparencyDay
26%6%12%24%21%8%
47163
Night
23%6%13%26%22%8%
46501
SeeingDay
8%9%31%28%17%5%
5670
Night
5%429%38%19%3
15794

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
221331236%8%63%
1432
16th to endDay
1323423337%64%
1713
February1st to 15thDay
2425%423348%58%
1642
16th to endDay
15%15%323447%60%
1580
March1st to 15thDay
242442336%8%56%
1833
16th to endDay
46%2422445%10%52%
2208
April1st to 15thDay
342333447%8%53%
2150
16th to endDay
7%6%35%435%45%7%46%
2160
May1st to 15thDay
9%6%35%435%6%6%8%39%
2292
16th to endDay
6%5%24435%5%8%10%44%
2616
June1st to 15thDay
4314325%5%8%9%51%
2520
16th to endDay
3213335%6%8%9%53%
2520
July1st to 15thDay
6%3245%36%6%7%10%42%
2520
16th to endDay
43235%36%8%8%11%40%
2609
August1st to 15thDay
5%325%6%36%7%9%9%39%
2206
16th to endDay
5%313436%6%9%9%46%
2100
September1st to 15thDay
6%3143245%6%10%49%
1980
16th to endDay
321231435%6%65%
1849
October1st to 15thDay
5%113313348%62%
1675
16th to endDay
4312112335%68%
1722
November1st to 15thDay
121331335%8%65%
1583
16th to endDay
212412347%69%
1599
December1st to 15thDay
1324424247%62%
1440
16th to endDay
342421345%8%58%
1536
January1st to 15thNight
224313346%66%
2506
16th to endNight
1313323335%68%
2523
February1st to 15thNight
142342445%7%58%
2210
16th to endNight
31442335%5%64%
1894
March1st to 15thNight
141232346%7%61%
2124
16th to endNight
3423323347%60%
2016
April1st to 15thNight
441232445%7%59%
1798
16th to endNight
8%6%24322347%54%
1800
May1st to 15thNight
9%5%233245%6%7%48%
1655
16th to endNight
7%423325%5%5%8%51%
1497
June1st to 15thNight
421222445%9%60%
1440
16th to endNight
2312225%5%7%8%58%
1440
July1st to 15thNight
5%3245%36%7%7%8%45%
1440
16th to endNight
43244345%8%12%46%
1557
August1st to 15thNight
5%315%5%45%6%6%9%47%
1668
16th to endNight
5%4133245%6%12%50%
1750
September1st to 15thNight
6%41443446%9%50%
1650
16th to endNight
3113213346%67%
1779
October1st to 15thNight
5%313213346%63%
1952
16th to endNight
4212212346%67%
2137
November1st to 15thNight
1113312348%67%
2275
16th to endNight
1322213336%70%
2358
December1st to 15thNight
122432335%9%60%
2520
16th to endNight
242342335%7%59%
2688

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
231321345%7%64%
1432
16th to endDay
1313423347%64%
1713
February1st to 15thDay
24345%23348%58%
1642
16th to endDay
1425%32335%7%59%
1580
March1st to 15thDay
343442335%8%57%
1833
16th to endDay
46%2331445%9%53%
2206
April1st to 15thDay
34234245%6%8%54%
2150
16th to endDay
8%7%244245%47%47%
2160
May1st to 15thDay
9%6%35%435%5%6%7%41%
2292
16th to endDay
7%414425%6%7%9%45%
2616
June1st to 15thDay
43134345%7%9%52%
2520
16th to endDay
3212425%6%8%8%53%
2520
July1st to 15thDay
6%3145%35%6%8%9%44%
2520
16th to endDay
43245%37%7%8%11%41%
2609
August1st to 15thDay
6%3245%46%7%8%9%41%
2206
16th to endDay
5%312436%5%8%9%48%
2100
September1st to 15thDay
6%3133246%6%10%51%
1980
16th to endDay
3212323446%65%
1849
October1st to 15thDay
5%213222446%64%
1675
16th to endDay
4312212345%69%
1722
November1st to 15thDay
121331435%8%65%
1583
16th to endDay
213312346%70%
1599
December1st to 15thDay
13245%23337%62%
1440
16th to endDay
35%3331345%8%57%
1536
January1st to 15thNight
1224413346%66%
2506
16th to endNight
1322323335%67%
2523
February1st to 15thNight
1424423447%59%
2210
16th to endNight
413324345%64%
1894
March1st to 15thNight
141332345%7%61%
2124
16th to endNight
3423323347%60%
2016
April1st to 15thNight
441232345%7%59%
1798
16th to endNight
9%7%13323348%53%
1800
May1st to 15thNight
9%5%1432446%7%49%
1655
16th to endNight
8%412325%5%5%9%51%
1497
June1st to 15thNight
42231435%9%61%
1440
16th to endNight
23123245%7%8%58%
1440
July1st to 15thNight
5%3235%37%6%7%8%46%
1440
16th to endNight
5%3144346%7%11%47%
1557
August1st to 15thNight
6%3145%35%6%6%9%47%
1668
16th to endNight
6%3123245%7%10%51%
1750
September1st to 15thNight
7%313435%5%6%9%50%
1650
16th to endNight
312312346%67%
1779
October1st to 15thNight
6%413213246%63%
1952
16th to endNight
4312212336%67%
2137
November1st to 15thNight
1212323248%68%
2275
16th to endNight
1223212345%70%
2358
December1st to 15thNight
132442335%8%60%
2520
16th to endNight
2424423347%59%
2688

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
17%5%12%32%26%6%
1433
16th to endDay
19%310%30%25%9%
1713
February1st to 15thDay
25%5%12%32%17%5%
1643
16th to endDay
23%48%27%26%8%
1580
March1st to 15thDay
24%5%11%25%25%8%
1833
16th to endDay
28%6%12%24%22%5%
2208
April1st to 15thDay
25%7%13%25%19%8%
2150
16th to endDay
35%6%12%23%16%5%
2160
May1st to 15thDay
39%7%12%21%16%2
2292
16th to endDay
31%9%15%22%13%6%
2620
June1st to 15thDay
25%7%15%20%19%12%
2520
16th to endDay
21%8%11%20%25%13%
2520
July1st to 15thDay
32%7%13%20%15%9%
2371
16th to endDay
30%11%16%23%14%3
2445
August1st to 15thDay
33%11%15%18%13%8%
2191
16th to endDay
27%9%13%22%21%5%
2100
September1st to 15thDay
26%8%13%21%19%11%
1980
16th to endDay
18%5%8%22%33%10%
1849
October1st to 15thDay
21%5%12%21%30%8%
1675
16th to endDay
18%39%25%30%12%
1722
November1st to 15thDay
16%411%25%26%14%
1583
16th to endDay
16%18%26%32%13%
1599
December1st to 15thDay
22%5%14%29%23%4
1440
16th to endDay
25%5%15%27%19%6%
1536
January1st to 15thNight
20%412%30%26%6%
2506
16th to endNight
19%410%28%26%10%
2523
February1st to 15thNight
24%5%12%31%20%5%
2220
16th to endNight
22%37%31%25%9%
1894
March1st to 15thNight
21%5%10%27%28%6%
2124
16th to endNight
22%7%12%23%28%6%
2016
April1st to 15thNight
23%7%13%25%21%9%
1798
16th to endNight
31%5%13%26%16%6%
1800
May1st to 15thNight
32%7%16%22%15%4
1656
16th to endNight
28%8%17%23%13%7%
1498
June1st to 15thNight
19%7%19%24%14%14%
1440
16th to endNight
20%9%13%21%20%14%
1440
July1st to 15thNight
32%10%15%20%13%7%
1360
16th to endNight
28%11%17%25%13%2
1458
August1st to 15thNight
32%10%16%21%11%7%
1659
16th to endNight
26%8%15%28%15%5%
1750
September1st to 15thNight
29%6%14%22%17%10%
1650
16th to endNight
18%5%10%26%30%8%
1779
October1st to 15thNight
22%6%11%21%28%9%
1952
16th to endNight
18%48%26%29%12%
2137
November1st to 15thNight
15%311%26%27%14%
2275
16th to endNight
17%29%27%31%11%
2358
December1st to 15thNight
20%6%15%30%20%5%
2520
16th to endNight
24%415%25%23%5%
2688

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
15%6%26%28%17%4
90
16th to endDay
5%7%27%41%18%
96
February1st to 15thDay
8%8%48%25%7%
90
16th to endDay
13%46%29%7%2
81
March1st to 15thDay
112%48%29%7%
123
16th to endDay
11%24%44%15%31
288
April1st to 15thDay
8%22%43%18%5%2
269
16th to endDay
18%24%34%16%4
270
May1st to 15thDay
13%12%31%30%8%3
414
16th to endDay
11%10%30%26%16%5%
517
June1st to 15thDay
5%9%28%28%21%6%
495
16th to endDay
36%26%29%26%7%
495
July1st to 15thDay
9%122%25%30%10%
475
16th to endDay
6%114%30%32%14%
468
August1st to 15thDay
11%424%35%18%5%
300
16th to endDay
8%425%42%12%7%
268
September1st to 15thDay
7%7%43%29%11%1
255
16th to endDay
35%31%23%25%10%
124
October1st to 15thDay
37%22%37%18%10%
90
16th to endDay
5%6%33%28%20%6%
96
November1st to 15thDay
25%25%31%26%8%
90
16th to endDay
6%12%46%23%10%1
90
December1st to 15thDay
37%57%24%5%1
90
16th to endDay
7%7%38%36%9%1
96
January1st to 15thNight
25%35%37%15%4
900
16th to endNight
3336%41%12%2
795
February1st to 15thNight
3446%37%8%
704
16th to endNight
26%45%37%8%
632
March1st to 15thNight
3441%36%12%1
720
16th to endNight
5%6%38%38%9%1
672
April1st to 15thNight
8%8%38%34%8%
539
16th to endNight
13%8%30%37%8%1
540
May1st to 15thNight
11%6%26%39%15%1
540
16th to endNight
9%328%38%17%2
563
June1st to 15thNight
4324%43%21%2
540
16th to endNight
3117%46%28%2
540
July1st to 15thNight
6%110%37%38%4
510
16th to endNight
5%6%34%46%5%
564
August1st to 15thNight
7%18%35%41%5%
527
16th to endNight
7%6%39%38%6%
525
September1st to 15thNight
7%112%43%29%5%
495
16th to endNight
4115%41%29%6%
492
October1st to 15thNight
8%327%34%19%5%
632
16th to endNight
4424%36%24%5%
729
November1st to 15thNight
2231%41%18%3
875
16th to endNight
25%31%42%14%3
900
December1st to 15thNight
2441%39%9%2
900
16th to endNight
47%39%36%9%2
960
Page generated at 2017-08-13 12:16:37. Version ac04

Copyright 2017 A. Danko


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