Steamboat Springs
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Steamboat Springs clear sky chart from 2005-11-05 to 2017-09-19.

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
48%
15970
20%
46904
15%
15929
52%
15929
28%
29758

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
35%
886
15%
2494
11%
883
39%
883
20%
1791
January16th to endNight
34%
768
18%
2496
14%
768
41%
768
20%
1706
February1st to 15thNight
28%
697
9%
2288
7%
697
32%
697
14%
1720
February16th to endNight
28%
632
15%
1923
8%
632
36%
632
18%
1364
March1st to 15thNight
40%
720
18%
2043
11%
720
47%
720
28%
1332
March16th to endNight
41%
729
19%
2073
13%
729
46%
729
25%
1396
April1st to 15thNight
41%
539
15%
1798
13%
539
46%
539
22%
1148
April16th to endNight
41%
540
19%
1800
17%
540
46%
540
23%
1144
May1st to 15thNight
47%
540
18%
1560
14%
540
51%
540
26%
1036
May16th to endNight
56%
563
18%
1498
13%
561
59%
561
31%
961
June1st to 15thNight
61%
540
23%
1440
16%
540
65%
540
48%
767
June16th to endNight
71%
540
30%
1440
23%
540
75%
540
57%
714
July1st to 15thNight
77%
510
19%
1360
16%
510
79%
510
48%
745
July16th to endNight
81%
564
22%
1506
21%
531
81%
531
44%
814
August1st to 15thNight
77%
539
22%
1611
22%
536
78%
536
39%
881
August16th to endNight
79%
573
30%
1893
32%
573
81%
573
44%
965
September1st to 15thNight
72%
540
28%
1800
30%
540
76%
540
40%
921
September16th to endNight
68%
573
33%
1832
31%
573
72%
573
45%
940
October1st to 15thNight
52%
660
26%
1980
18%
660
58%
660
33%
1186
October16th to endNight
50%
704
28%
2112
17%
704
57%
704
36%
1207
November1st to 15thNight
42%
853
22%
2253
13%
853
48%
853
32%
1451
November16th to endNight
41%
900
21%
2496
13%
900
46%
900
30%
1587
December1st to 15thNight
27%
900
8%
2520
5%
900
30%
900
17%
1890
December16th to endNight
26%
960
11%
2688
6%
960
30%
960
15%
2092

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
6%10%46%5%2445%7%42%
47928
Night
5%11%46%423346%45%
47084
TransparencyDay
40%5%11%21%15%5%
47610
Night
39%5%12%22%14%4
46904
SeeingDay
12%15%29%25%14%2
5859
Night
10%9%24%33%19%2
15979

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
5%17%7%10%5%24336%32%
1456
16th to endDay
5%15%11%11%6%1224433%
1728
February1st to 15thDay
7%18%9%12%5%2322429%
1575
16th to endDay
418%10%12%7%23446%26%
1549
March1st to 15thDay
414%6%10%5%23346%40%
1917
16th to endDay
415%7%7%5%245%5%8%33%
2151
April1st to 15thDay
7%15%5%6%435%35%7%35%
2150
16th to endDay
6%15%46%6%35%5%6%8%31%
2160
May1st to 15thDay
10%9%26%5%36%5%6%6%35%
2388
16th to endDay
9%7%25%435%5%7%9%38%
2616
June1st to 15thDay
5%313425%46%8%54%
2520
16th to endDay
212314448%66%
2520
July1st to 15thDay
5%214435%5%8%8%49%
2520
16th to endDay
4315%6%46%7%6%9%44%
2555
August1st to 15thDay
6%4246%35%6%7%9%43%
2340
16th to endDay
4314435%5%6%9%50%
2309
September1st to 15thDay
7%323425%447%54%
2160
16th to endDay
10%5%13412235%58%
1870
October1st to 15thDay
10%9%24423448%46%
1650
16th to endDay
9%11%2432335%5%48%
1760
November1st to 15thDay
7%11%5%5%413336%46%
1594
16th to endDay
5%12%48%412246%46%
1464
December1st to 15thDay
6%20%6%12%6%22345%27%
1440
16th to endDay
5%22%9%13%6%2433424%
1536
January1st to 15thNight
5%18%7%9%5%23235%36%
2494
16th to endNight
5%17%8%10%5%2312339%
2496
February1st to 15thNight
6%17%9%12%6%23335%28%
2277
16th to endNight
417%8%11%5%23347%31%
1923
March1st to 15thNight
313%5%7%423346%43%
2043
16th to endNight
413%5%7%424445%42%
2073
April1st to 15thNight
6%13%45%424446%42%
1798
16th to endNight
8%14%36%414445%42%
1800
May1st to 15thNight
9%9%35%435%46%7%41%
1559
16th to endNight
7%6%25%5%2445%9%45%
1497
June1st to 15thNight
33122235%5%7%61%
1440
16th to endNight
2212213347%68%
1440
July1st to 15thNight
32123135%6%9%59%
1440
16th to endNight
1213325%6%6%9%56%
1610
August1st to 15thNight
3314425%48%8%52%
1620
16th to endNight
322332445%9%56%
1893
September1st to 15thNight
431432445%7%58%
1800
16th to endNight
7%412312335%63%
1832
October1st to 15thNight
10%8%1431335%5%51%
1980
16th to endNight
7%9%24323346%53%
2112
November1st to 15thNight
6%11%45%423336%48%
2253
16th to endNight
412%47%323346%45%
2496
December1st to 15thNight
8%17%6%10%7%3332431%
2520
16th to endNight
6%18%9%14%6%2332427%
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
53%418%16%5%1
1457
16th to endDay
53%315%17%8%1
1728
February1st to 15thDay
59%313%15%6%
1575
16th to endDay
59%5%11%15%6%
1549
March1st to 15thDay
46%416%21%10%1
1917
16th to endDay
49%5%10%24%7%2
2151
April1st to 15thDay
47%414%19%11%2
2150
16th to endDay
48%6%11%24%8%
2160
May1st to 15thDay
44%6%11%22%13%
2388
16th to endDay
40%6%13%25%12%1
2620
June1st to 15thDay
26%6%10%21%25%9%
2520
16th to endDay
17%5%420%35%17%
2520
July1st to 15thDay
28%9%11%16%19%15%
2371
16th to endDay
33%7%12%19%16%10%
2396
August1st to 15thDay
34%8%12%17%18%9%
2325
16th to endDay
28%7%9%27%20%7%
2309
September1st to 15thDay
28%5%9%19%23%13%
2160
16th to endDay
29%37%30%24%3
1870
October1st to 15thDay
37%5%10%29%15%2
1650
16th to endDay
36%5%10%32%12%2
1760
November1st to 15thDay
39%412%21%18%2
1594
16th to endDay
39%316%28%11%1
1464
December1st to 15thDay
59%318%13%4
1440
16th to endDay
63%5%8%15%5%1
1536
January1st to 15thNight
51%414%20%7%1
2494
16th to endNight
51%212%20%10%1
2496
February1st to 15thNight
59%412%16%7%
2288
16th to endNight
51%5%11%20%9%1
1923
March1st to 15thNight
41%416%23%12%1
2043
16th to endNight
43%5%11%28%8%1
2073
April1st to 15thNight
41%6%13%20%15%2
1798
16th to endNight
43%412%24%14%
1800
May1st to 15thNight
40%7%11%26%12%1
1560
16th to endNight
34%8%13%27%15%1
1498
June1st to 15thNight
20%5%13%25%24%10%
1440
16th to endNight
15%5%5%20%30%23%
1440
July1st to 15thNight
21%6%16%19%17%18%
1360
16th to endNight
23%6%18%20%18%12%
1506
August1st to 15thNight
25%7%14%22%17%13%
1611
16th to endNight
22%5%12%22%26%10%
1893
September1st to 15thNight
25%412%17%23%15%
1800
16th to endNight
24%37%30%28%5%
1832
October1st to 15thNight
33%6%9%29%17%4
1980
16th to endNight
32%312%32%17%1
2112
November1st to 15thNight
37%411%24%17%3
2253
16th to endNight
38%414%27%13%1
2496
December1st to 15thNight
56%415%16%7%
2520
16th to endNight
61%311%16%5%1
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
25%14%24%16%17%1
90
16th to endDay
15%16%35%27%5%
96
February1st to 15thDay
25%21%32%17%3
90
16th to endDay
12%30%25%24%6%
81
March1st to 15thDay
19%25%26%20%8%
207
16th to endDay
19%29%36%11%2
288
April1st to 15thDay
19%30%26%16%5%
269
16th to endDay
22%28%31%14%3
270
May1st to 15thDay
17%18%32%19%11%1
366
16th to endDay
16%12%29%24%14%2
517
June1st to 15thDay
6%12%29%27%20%3
495
16th to endDay
311%28%30%23%3
495
July1st to 15thDay
7%5%20%33%29%3
475
16th to endDay
8%5%27%32%22%3
414
August1st to 15thDay
9%9%37%32%10%1
315
16th to endDay
6%7%28%33%20%2
332
September1st to 15thDay
8%16%32%26%12%3
315
16th to endDay
15%7%33%28%10%4
192
October1st to 15thDay
6%14%30%33%10%5%
90
16th to endDay
25%8%33%23%8%1
96
November1st to 15thDay
5%17%28%18%20%8%
90
16th to endDay
18%24%40%15%1
90
December1st to 15thDay
22%27%36%11%2
90
16th to endDay
11%32%34%18%3
96
January1st to 15thNight
14%16%26%30%10%1
888
16th to endNight
12%13%31%29%11%1
768
February1st to 15thNight
13%12%32%32%7%
704
16th to endNight
11%16%35%29%6%
632
March1st to 15thNight
9%10%32%31%14%1
720
16th to endNight
12%11%28%35%11%
729
April1st to 15thNight
12%12%29%35%9%1
539
16th to endNight
17%10%26%29%13%1
540
May1st to 15thNight
14%7%23%36%16%1
540
16th to endNight
11%5%18%36%23%4
563
June1st to 15thNight
7%5%20%39%25%2
540
16th to endNight
2317%45%29%2
540
July1st to 15thNight
418%39%42%3
510
16th to endNight
11437%49%4
564
August1st to 15thNight
5%7%39%43%2
539
16th to endNight
418%38%41%5%
573
September1st to 15thNight
6%113%41%32%5%
540
16th to endNight
8%414%32%33%7%
573
October1st to 15thNight
12%6%23%37%16%3
660
16th to endNight
10%9%25%30%19%3
704
November1st to 15thNight
12%10%30%29%16%
853
16th to endNight
10%14%28%32%12%1
900
December1st to 15thNight
15%16%33%27%6%
900
16th to endNight
14%15%33%27%8%
960
Page generated at 2017-09-20 02:49:49. Version ac04

Copyright 2017 A. Danko


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