WindingRidge Homestead
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the WindingRidge Homestead clear sky chart from 2005-11-05 to 2017-10-06.

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
45%
15740
26%
47101
17%
15693
54%
15693
33%
27157

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
32%
900
29%
2327
11%
895
43%
895
33%
1399
January16th to endNight
31%
960
31%
2496
11%
960
44%
960
33%
1492
February1st to 15thNight
27%
880
21%
2288
8%
876
36%
876
29%
1465
February16th to endNight
27%
567
27%
1829
10%
567
42%
567
27%
1041
March1st to 15thNight
28%
540
22%
1980
13%
540
40%
540
23%
1200
March16th to endNight
30%
576
20%
2112
14%
576
41%
576
22%
1271
April1st to 15thNight
31%
539
22%
1887
14%
539
43%
539
26%
1067
April16th to endNight
35%
540
24%
1784
14%
540
50%
540
30%
1017
May1st to 15thNight
39%
540
21%
1620
13%
540
50%
540
29%
993
May16th to endNight
44%
563
23%
1685
16%
561
55%
561
34%
985
June1st to 15thNight
65%
540
23%
1620
20%
540
71%
540
45%
843
June16th to endNight
68%
540
26%
1620
23%
540
74%
540
50%
817
July1st to 15thNight
70%
510
18%
1530
18%
510
73%
510
39%
862
July16th to endNight
83%
564
28%
1594
32%
531
85%
531
48%
819
August1st to 15thNight
79%
539
27%
1610
31%
536
81%
536
46%
844
August16th to endNight
72%
573
26%
1855
31%
573
73%
573
34%
1060
September1st to 15thNight
69%
540
26%
1900
29%
540
72%
540
34%
1024
September16th to endNight
66%
537
34%
1980
34%
537
72%
537
37%
996
October1st to 15thNight
53%
658
29%
2026
22%
658
58%
658
37%
1131
October16th to endNight
43%
704
34%
2112
19%
704
55%
704
41%
1101
November1st to 15thNight
44%
700
31%
2100
19%
700
55%
700
37%
1132
November16th to endNight
35%
870
29%
2310
15%
870
45%
870
32%
1436
December1st to 15thNight
34%
900
25%
2340
11%
900
43%
900
30%
1506
December16th to endNight
32%
960
25%
2496
11%
960
41%
960
26%
1656

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
11%5%2443445%7%46%
48095
Night
9%5%24323347%53%
47296
TransparencyDay
37%6%11%22%18%4
47795
Night
31%5%10%23%22%6%
47101
SeeingDay
11%8%25%28%20%5%
5767
Night
13%10%26%30%17%1
15740

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
12%7%24323435%50%
1611
16th to endDay
13%5%23323336%50%
1728
February1st to 15thDay
13%8%35%42333445%
1578
16th to endDay
14%8%26%323335%44%
1652
March1st to 15thDay
14%7%35%424336%44%
1980
16th to endDay
17%7%35%5%24336%39%
2110
April1st to 15thDay
12%6%25%5%24346%46%
2061
16th to endDay
15%8%36%5%33435%41%
2174
May1st to 15thDay
15%6%35%434445%41%
2331
16th to endDay
9%6%36%6%35%5%5%9%39%
2430
June1st to 15thDay
7%4245%45%5%6%9%43%
2340
16th to endDay
5%324435%5%6%8%48%
2340
July1st to 15thDay
8%425%6%46%7%8%9%37%
2340
16th to endDay
5%2145%48%7%7%9%45%
2466
August1st to 15thDay
5%3245%35%5%6%10%47%
2340
16th to endDay
7%325%6%46%7%6%9%39%
2345
September1st to 15thDay
14%3244246%6%6%44%
2058
16th to endDay
8%314423447%54%
1980
October1st to 15thDay
11%6%24423335%51%
1718
16th to endDay
11%312322335%60%
1760
November1st to 15thDay
6%5%13323447%57%
1758
16th to endDay
13%6%23324335%52%
1647
December1st to 15thDay
13%8%24422345%48%
1620
16th to endDay
15%7%3442335%5%44%
1728
January1st to 15thNight
11%5%13313245%55%
2327
16th to endNight
10%5%24312335%56%
2496
February1st to 15thNight
11%7%26%422335%49%
2278
16th to endNight
10%6%23423346%52%
1829
March1st to 15thNight
15%7%24413446%45%
1980
16th to endNight
13%6%24424445%46%
2112
April1st to 15thNight
10%4245%23446%50%
1887
16th to endNight
10%5%23413347%51%
1784
May1st to 15thNight
11%325%42435%8%47%
1619
16th to endNight
7%42333445%11%47%
1683
June1st to 15thNight
322332335%9%59%
1620
16th to endNight
421221335%10%60%
1620
July1st to 15thNight
4314425%5%7%11%48%
1620
16th to endNight
31123136%6%11%58%
1702
August1st to 15thNight
12134245%8%9%56%
1620
16th to endNight
4424436%45%8%50%
1855
September1st to 15thNight
9%42432345%7%53%
1900
16th to endNight
7%31341345%6%58%
1980
October1st to 15thNight
10%423413446%55%
2026
16th to endNight
11%3321122464%
2112
November1st to 15thNight
6%413323345%60%
2100
16th to endNight
14%5%1431333453%
2310
December1st to 15thNight
16%6%24322245%49%
2340
16th to endNight
11%8%36%42344446%
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
35%48%24%21%5%
1612
16th to endDay
35%47%25%23%3
1728
February1st to 15thDay
42%39%20%19%3
1579
16th to endDay
43%27%21%18%5%
1652
March1st to 15thDay
42%410%19%16%7%
1980
16th to endDay
46%49%22%14%2
2112
April1st to 15thDay
38%6%11%20%18%4
2061
16th to endDay
46%5%8%17%18%3
2174
May1st to 15thDay
45%5%9%16%19%3
2331
16th to endDay
40%7%12%24%14%
2434
June1st to 15thDay
35%8%12%24%16%1
2340
16th to endDay
30%7%15%24%19%2
2340
July1st to 15thDay
37%8%16%26%10%
2201
16th to endDay
29%10%16%27%15%1
2311
August1st to 15thDay
31%7%14%26%17%2
2326
16th to endDay
38%9%14%22%12%2
2345
September1st to 15thDay
37%7%11%19%15%9%
2058
16th to endDay
28%6%11%25%22%6%
1980
October1st to 15thDay
35%410%19%21%8%
1718
16th to endDay
28%37%22%28%10%
1760
November1st to 15thDay
27%411%26%22%6%
1758
16th to endDay
34%46%19%26%7%
1647
December1st to 15thDay
38%311%24%17%4
1620
16th to endDay
41%47%22%19%4
1728
January1st to 15thNight
31%39%21%29%4
2327
16th to endNight
31%38%22%26%7%
2496
February1st to 15thNight
38%38%25%18%6%
2288
16th to endNight
33%410%26%18%6%
1829
March1st to 15thNight
40%410%16%19%7%
1980
16th to endNight
38%6%10%22%17%4
2112
April1st to 15thNight
33%5%11%19%20%9%
1887
16th to endNight
32%5%10%22%23%4
1784
May1st to 15thNight
34%7%13%20%16%7%
1620
16th to endNight
30%7%16%28%14%2
1685
June1st to 15thNight
22%5%14%31%23%3
1620
16th to endNight
19%5%13%28%28%4
1620
July1st to 15thNight
25%8%17%28%18%1
1530
16th to endNight
18%7%15%34%21%2
1594
August1st to 15thNight
20%8%16%29%21%4
1610
16th to endNight
30%6%12%26%19%3
1855
September1st to 15thNight
29%5%10%23%20%10%
1900
16th to endNight
26%5%9%25%25%8%
1980
October1st to 15thNight
29%411%20%20%12%
2026
16th to endNight
25%26%20%30%14%
2112
November1st to 15thNight
27%39%26%23%10%
2100
16th to endNight
34%46%18%28%8%
2310
December1st to 15thNight
38%310%20%20%6%
2340
16th to endNight
40%48%20%18%6%
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
22%16%36%20%31
90
16th to endDay
21%31%25%13%8%
96
February1st to 15thDay
22%17%38%16%4
90
16th to endDay
20%22%40%11%31
81
March1st to 15thDay
27%23%33%14%1
90
16th to endDay
16%23%36%16%6%
96
April1st to 15thDay
18%17%33%21%7%
180
16th to endDay
22%15%30%20%9%1
284
May1st to 15thDay
16%17%37%18%8%1
468
16th to endDay
11%12%38%21%13%2
517
June1st to 15thDay
8%425%35%20%6%
495
16th to endDay
5%324%38%20%7%
495
July1st to 15thDay
7%122%38%24%5%
475
16th to endDay
47%33%40%13%
515
August1st to 15thDay
7%112%34%38%6%
493
16th to endDay
8%213%30%34%10%
385
September1st to 15thDay
6%213%28%36%13%
213
16th to endDay
8%218%36%22%11%
135
October1st to 15thDay
8%6%31%36%13%3
107
16th to endDay
13%7%39%28%10%1
96
November1st to 15thDay
10%10%30%34%14%1
90
16th to endDay
35%21%23%13%24
90
December1st to 15thDay
23%14%35%18%43
90
16th to endDay
25%20%32%16%5%
96
January1st to 15thNight
18%17%29%27%6%
900
16th to endNight
14%20%30%28%6%
960
February1st to 15thNight
17%17%34%25%5%
880
16th to endNight
17%16%35%25%4
567
March1st to 15thNight
22%10%35%27%4
540
16th to endNight
16%13%36%25%7%
576
April1st to 15thNight
12%19%33%27%6%
539
16th to endNight
12%14%34%26%10%
540
May1st to 15thNight
12%9%33%31%12%
540
16th to endNight
9%7%33%27%21%1
563
June1st to 15thNight
5%220%38%31%2
540
16th to endNight
4220%38%29%5%
540
July1st to 15thNight
416%36%39%3
510
16th to endNight
46%35%48%4
564
August1st to 15thNight
210%40%38%7%
539
16th to endNight
7%10%36%39%6%
573
September1st to 15thNight
11%110%33%39%4
540
16th to endNight
10%214%31%36%4
537
October1st to 15thNight
12%425%28%24%4
658
16th to endNight
13%10%29%28%16%1
704
November1st to 15thNight
10%14%27%32%14%1
700
16th to endNight
19%13%30%26%10%
870
December1st to 15thNight
21%11%29%29%7%
900
16th to endNight
18%16%28%28%7%
960
Page generated at 2017-10-07 13:07:44. Version ac04

Copyright 2017 A. Danko


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