Owl Canyon Campground
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Owl Canyon Campground clear sky chart from 2005-11-05 to 2017-12-01.

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
62%
16100
39%
47537
27%
16059
73%
16059
61%
20719

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
64%
717
32%
2327
28%
716
72%
716
49%
1062
January16th to endNight
60%
768
38%
2352
30%
768
72%
768
49%
1120
February1st to 15thNight
58%
698
35%
2109
30%
697
68%
697
52%
986
February16th to endNight
54%
632
35%
1895
29%
632
66%
632
47%
922
March1st to 15thNight
54%
720
34%
2160
26%
720
68%
720
53%
982
March16th to endNight
48%
768
37%
2033
20%
768
63%
768
55%
981
April1st to 15thNight
41%
719
36%
1799
12%
719
56%
719
54%
877
April16th to endNight
46%
720
41%
1800
13%
720
61%
720
64%
824
May1st to 15thNight
45%
546
39%
1625
19%
545
57%
545
68%
635
May16th to endNight
41%
562
37%
1685
17%
561
57%
561
62%
665
June1st to 15thNight
43%
529
35%
1609
19%
529
57%
529
70%
610
June16th to endNight
54%
360
43%
1440
33%
360
75%
360
82%
406
July1st to 15thNight
73%
357
35%
1377
31%
357
84%
357
65%
471
July16th to endNight
71%
567
36%
1596
26%
534
76%
534
61%
706
August1st to 15thNight
73%
717
39%
1790
19%
713
79%
713
82%
792
August16th to endNight
82%
764
45%
1910
28%
764
86%
764
79%
866
September1st to 15thNight
80%
720
41%
1863
27%
720
86%
720
75%
836
September16th to endNight
76%
716
50%
1980
38%
716
87%
716
83%
781
October1st to 15thNight
66%
720
42%
1980
30%
720
78%
720
69%
859
October16th to endNight
72%
768
47%
2353
41%
768
84%
768
66%
961
November1st to 15thNight
73%
760
38%
2470
36%
760
81%
760
61%
1011
November16th to endNight
72%
780
42%
2535
41%
780
80%
780
59%
1045
December1st to 15thNight
64%
724
35%
2353
30%
724
73%
724
48%
1098
December16th to endNight
58%
768
34%
2496
28%
768
68%
768
43%
1223

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
2111212235%75%
48884
Night
2111212235%75%
47727
TransparencyDay
12%25%15%26%37%
48571
Night
12%26%17%28%33%
47541
SeeingDay
410%23%32%23%5%
6103
Night
28%23%35%25%4
16110

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
321331235%6%66%
1611
16th to endDay
4423313346%62%
1869
February1st to 15thDay
2211222347%68%
1751
16th to endDay
5%313422435%63%
1579
March1st to 15thDay
121111235%8%69%
1800
16th to endDay
222223347%68%
2187
April1st to 15thDay
2212212235%72%
2149
16th to endDay
111111235%79%
2160
May1st to 15thDay
1111122482%
2325
16th to endDay
11111222380%
2429
June1st to 15thDay
11112483%
2346
16th to endDay
11111287%
2520
July1st to 15thDay
2111212335%74%
2499
16th to endDay
2113323335%68%
2461
August1st to 15thDay
11111223381%
2160
16th to endDay
1111222380%
2292
September1st to 15thDay
11121123480%
2097
16th to endDay
11111287%
1980
October1st to 15thDay
11121223478%
1980
16th to endDay
1111113481%
1867
November1st to 15thDay
121121223476%
1719
16th to endDay
2112212336%71%
1755
December1st to 15thDay
322322335%10%61%
1620
16th to endDay
5%32332235%6%62%
1728
January1st to 15thNight
3213323345%66%
2327
16th to endNight
4312312345%67%
2352
February1st to 15thNight
3323112247%67%
2101
16th to endNight
5%212213446%64%
1895
March1st to 15thNight
1112213447%68%
2160
16th to endNight
1212112348%69%
2033
April1st to 15thNight
1212212345%73%
1799
16th to endNight
1111122481%
1800
May1st to 15thNight
12235%81%
1625
16th to endNight
111122482%
1684
June1st to 15thNight
1112385%
1609
16th to endNight
1111290%
1440
July1st to 15thNight
21111113380%
1458
16th to endNight
2212212335%72%
1704
August1st to 15thNight
11113483%
1800
16th to endNight
111123383%
1910
September1st to 15thNight
1111122381%
1863
16th to endNight
12289%
1980
October1st to 15thNight
1121222479%
1980
16th to endNight
11111222480%
2353
November1st to 15thNight
21221223476%
2470
16th to endNight
2111212337%72%
2535
December1st to 15thNight
4212223338%65%
2353
16th to endNight
5%313323345%63%
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
19%39%24%28%14%
1612
16th to endDay
23%29%22%24%17%
1869
February1st to 15thDay
15%37%22%28%22%
1751
16th to endDay
21%38%21%30%14%
1579
March1st to 15thDay
12%27%24%31%22%
1800
16th to endDay
14%38%24%29%19%
2187
April1st to 15thDay
14%3419%33%24%
2149
16th to endDay
8%26%19%31%31%
2160
May1st to 15thDay
7%2417%30%37%
2325
16th to endDay
9%2413%35%35%
2432
June1st to 15thDay
6%129%23%55%
2346
16th to endDay
7%2312%73%
2520
July1st to 15thDay
11%25%6%15%58%
2351
16th to endDay
18%3410%19%43%
2306
August1st to 15thDay
9%126%16%63%
2146
16th to endDay
10%135%23%55%
2292
September1st to 15thDay
9%246%22%53%
2097
16th to endDay
6%116%28%55%
1980
October1st to 15thDay
10%2212%31%40%
1980
16th to endDay
8%2414%27%43%
1867
November1st to 15thDay
12%16%19%36%23%
1719
16th to endDay
14%27%18%32%24%
1755
December1st to 15thDay
18%411%24%25%15%
1620
16th to endDay
21%5%13%26%21%11%
1728
January1st to 15thNight
18%37%20%30%19%
2327
16th to endNight
19%28%21%23%23%
2352
February1st to 15thNight
17%28%21%25%25%
2112
16th to endNight
19%28%22%28%17%
1895
March1st to 15thNight
14%38%21%28%22%
2160
16th to endNight
12%39%25%29%19%
2033
April1st to 15thNight
12%28%24%30%20%
1799
16th to endNight
8%15%25%34%25%
1800
May1st to 15thNight
6%15%22%34%29%
1626
16th to endNight
7%15%19%39%25%
1685
June1st to 15thNight
6%313%25%50%
1609
16th to endNight
317%17%68%
1440
July1st to 15thNight
9%127%19%59%
1377
16th to endNight
14%25%11%23%42%
1596
August1st to 15thNight
5%128%25%55%
1790
16th to endNight
7%127%29%51%
1910
September1st to 15thNight
8%239%28%47%
1863
16th to endNight
428%29%54%
1980
October1st to 15thNight
8%2412%33%38%
1980
16th to endNight
9%2310%25%47%
2353
November1st to 15thNight
12%2416%35%28%
2470
16th to endNight
12%25%19%27%32%
2535
December1st to 15thNight
18%310%19%28%19%
2353
16th to endNight
22%312%21%26%13%
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
12%11%26%37%12%
90
16th to endDay
10%13%21%30%19%4
237
February1st to 15thDay
6%13%23%30%20%6%
266
16th to endDay
9%19%23%27%16%2
238
March1st to 15thDay
9%14%25%27%18%4
270
16th to endDay
7%19%26%28%17%2
288
April1st to 15thDay
10%20%26%24%13%5%
269
16th to endDay
424%31%22%14%2
270
May1st to 15thDay
317%29%27%17%3
288
16th to endDay
416%26%29%17%4
330
June1st to 15thDay
213%30%25%22%4
315
16th to endDay
25%32%28%25%5%
315
July1st to 15thDay
2121%40%26%7%
305
16th to endDay
315%37%33%9%
327
August1st to 15thDay
3222%38%27%6%
315
16th to endDay
2115%36%34%9%
332
September1st to 15thDay
320%42%26%6%
315
16th to endDay
35%16%38%29%6%
315
October1st to 15thDay
49%25%36%21%2
315
16th to endDay
5%6%17%25%33%12%
247
November1st to 15thDay
28%18%28%29%11%
135
16th to endDay
412%11%34%28%7%
135
December1st to 15thDay
35%25%38%23%3
90
16th to endDay
9%14%12%43%18%1
96
January1st to 15thNight
35%18%36%28%6%
720
16th to endNight
6%7%20%33%27%4
768
February1st to 15thNight
49%21%33%26%4
704
16th to endNight
5%12%25%34%18%4
632
March1st to 15thNight
110%28%34%20%4
720
16th to endNight
116%30%30%18%2
768
April1st to 15thNight
219%33%25%15%2
719
16th to endNight
117%33%29%16%2
720
May1st to 15thNight
111%40%30%14%1
546
16th to endNight
118%36%30%13%
563
June1st to 15thNight
111%43%31%11%
529
16th to endNight
341%43%10%
360
July1st to 15thNight
1120%53%22%
357
16th to endNight
319%56%19%
567
August1st to 15thNight
122%43%29%3
717
16th to endNight
112%40%39%5%
764
September1st to 15thNight
1112%36%42%5%
720
16th to endNight
416%31%40%5%
716
October1st to 15thNight
5%24%34%30%4
720
16th to endNight
2416%27%36%12%
768
November1st to 15thNight
15%15%38%32%6%
760
16th to endNight
26%14%35%33%7%
780
December1st to 15thNight
5%6%18%35%28%5%
724
16th to endNight
6%8%21%36%23%3
768
Page generated at 2017-12-02 06:14:21. Version ac04

Copyright 2017 A. Danko


Owl Canyon Campground Clear Sky Chart |Charts Home