Yoder Observing Site
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Yoder Observing Site clear sky chart from 2005-11-06 to 2024-03-08.

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
52%
24145
22%
79740
17%
24040
59%
24040
27%
48870

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 10thNight
28%
751
22%
3996
11%
737
44%
737
16%
2257
January11th to 20thNight
37%
757
29%
3918
17%
740
51%
740
19%
2009
January21st to endNight
29%
834
18%
4255
12%
814
44%
814
15%
2644
February1st to 10thNight
36%
760
24%
2280
13%
760
47%
760
27%
1439
February11th to 20thNight
33%
743
23%
2218
10%
739
46%
739
27%
1393
February21st to endNight
32%
628
23%
1884
12%
628
42%
628
27%
1190
March1st to 10thNight
40%
751
28%
2169
16%
751
49%
751
33%
1306
March11th to 20thNight
39%
720
22%
1980
11%
720
48%
720
30%
1260
March21st to endNight
42%
792
23%
2178
12%
792
50%
792
32%
1345
April1st to 10thNight
46%
720
24%
1980
17%
720
52%
720
33%
1229
April11th to 20thNight
49%
561
27%
1803
19%
561
57%
561
33%
1024
April21st to endNight
60%
540
32%
1672
24%
540
68%
540
42%
885
May1st to 10thNight
59%
540
26%
1620
19%
540
65%
540
39%
894
May11th to 20thNight
61%
531
17%
1592
13%
531
64%
531
30%
1003
May21st to endNight
69%
582
22%
1744
19%
582
71%
582
32%
1078
June1st to 10thNight
63%
540
14%
1620
12%
540
63%
540
24%
1118
June11th to 20thNight
77%
540
18%
1620
15%
540
78%
540
33%
984
June21st to endNight
71%
540
13%
1620
12%
540
71%
540
26%
1081
July1st to 10thNight
74%
525
10%
1575
8%
525
74%
525
21%
1123
July11th to 20thNight
74%
522
9%
1566
9%
522
74%
522
25%
1066
July21st to endNight
78%
591
14%
1672
13%
558
78%
558
28%
1097
August1st to 10thNight
75%
537
12%
1600
13%
534
75%
534
26%
1073
August11th to 20thNight
72%
534
14%
1772
15%
534
72%
534
21%
1192
August21st to endNight
66%
605
15%
1991
17%
605
67%
605
19%
1391
September1st to 10thNight
67%
720
17%
1980
15%
720
67%
720
25%
1359
September11th to 20thNight
63%
720
19%
1980
16%
720
65%
720
27%
1327
September21st to endNight
64%
720
25%
1980
21%
720
67%
720
30%
1267
October1st to 10thNight
61%
720
28%
1980
23%
720
66%
720
37%
1192
October11th to 20thNight
59%
720
33%
2074
27%
720
66%
720
40%
1157
October21st to endNight
55%
792
32%
2376
27%
792
63%
792
38%
1330
November1st to 10thNight
55%
740
29%
2308
25%
740
63%
740
35%
1316
November11th to 20thNight
49%
760
29%
2470
23%
760
60%
760
34%
1365
November21st to endNight
44%
760
26%
2470
20%
760
55%
760
29%
1483
December1st to 10thNight
42%
760
27%
2470
18%
760
54%
760
27%
1496
December11th to 20thNight
40%
759
26%
2905
17%
758
50%
758
23%
1696
December21st to endNight
38%
830
15%
4422
17%
817
46%
817
13%
2801

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
12%5%25%5%35%5%6%8%43%
78983
Night
12%5%25%5%35%5%6%8%45%
80592
TransparencyDay
38%8%11%17%19%7%
78706
Night
36%7%11%17%20%8%
80388
SeeingDay
12%7%20%24%23%14%
14028
Night
13%5%22%32%24%4
24168

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 10thDay
16%5%35%434447%45%
2836
11th to 20thDay
12%6%23322346%56%
2840
21st to endDay
19%7%345%34446%42%
3317
February1st to 10thDay
15%7%37%4345%5%6%41%
1900
11th to 20thDay
18%5%2443435%6%45%
1848
21st to endDay
16%7%345%34347%43%
1570
March1st to 10thDay
13%4246%3435%6%49%
1952
11th to 20thDay
13%5%36%5%36%45%7%43%
1980
21st to endDay
13%5%26%4345%5%7%46%
2178
April1st to 10thDay
12%6%25%5%3445%7%47%
1980
11th to 20thDay
13%425%42445%8%49%
2120
21st to endDay
7%31443445%8%56%
2286
May1st to 10thDay
7%424425%46%7%55%
2340
11th to 20thDay
7%6%26%6%46%5%7%9%43%
2301
21st to endDay
8%5%247%36%5%7%9%43%
2531
June1st to 10thDay
11%6%26%8%5%7%7%8%9%32%
2340
11th to 20thDay
6%425%6%46%6%8%11%42%
2340
21st to endDay
6%5%26%7%5%7%6%9%11%35%
2340
July1st to 10thDay
8%5%27%9%6%8%8%9%11%28%
2340
11th to 20thDay
8%5%37%8%5%7%8%8%11%30%
2340
21st to endDay
7%436%7%5%8%7%8%12%33%
2547
August1st to 10thDay
9%5%27%6%5%7%7%10%12%30%
2327
11th to 20thDay
9%7%37%8%6%8%7%7%11%28%
2125
21st to endDay
13%7%37%7%5%6%6%7%9%30%
2345
September1st to 10thDay
9%5%27%6%46%6%7%10%37%
1980
11th to 20thDay
13%5%35%6%35%6%6%8%40%
1980
21st to endDay
13%6%36%6%35%45%5%44%
1980
October1st to 10thDay
13%5%245%33446%52%
1980
11th to 20thDay
11%3233245%38%56%
1886
21st to endDay
11%325%324446%55%
1980
November1st to 10thDay
11%5%2332445%455%
1767
11th to 20thDay
13%424423446%54%
1710
21st to endDay
15%5%345%345%46%47%
1710
December1st to 10thDay
16%6%25%5%35%446%43%
1710
11th to 20thDay
18%6%25%434436%45%
2153
21st to endDay
19%7%36%423345%43%
3124
January1st to 10thNight
18%6%244445%5%7%42%
4109
11th to 20thNight
10%5%24435%5%6%8%48%
4120
21st to endNight
20%7%35%5%33345%41%
4336
February1st to 10thNight
15%6%35%5%3445%6%45%
2280
11th to 20thNight
19%5%24423446%47%
2218
21st to endNight
15%6%35%42446%6%45%
1884
March1st to 10thNight
12%5%25%42345%7%51%
2169
11th to 20thNight
13%5%246%335%6%8%45%
1980
21st to endNight
11%5%25%43445%7%50%
2178
April1st to 10thNight
11%4246%3445%7%49%
1980
11th to 20thNight
12%42442445%7%51%
1803
21st to endNight
6%42332446%8%58%
1672
May1st to 10thNight
6%4144245%6%8%55%
1620
11th to 20thNight
7%6%25%6%35%6%6%9%45%
1592
21st to endNight
8%5%35%5%35%47%10%44%
1744
June1st to 10thNight
8%6%36%7%5%6%7%7%11%32%
1620
11th to 20thNight
43245%46%7%8%13%43%
1620
21st to endNight
45%36%6%48%7%9%11%36%
1620
July1st to 10thNight
7%435%6%5%8%8%10%13%31%
1620
11th to 20thNight
6%5%35%6%47%9%10%12%34%
1620
21st to endNight
6%325%7%5%6%8%9%14%37%
1771
August1st to 10thNight
5%5%25%6%47%8%8%12%37%
1611
11th to 20thNight
9%5%25%7%46%7%9%12%35%
1772
21st to endNight
11%6%36%7%47%7%7%11%32%
1991
September1st to 10thNight
10%6%36%6%5%6%6%7%9%37%
1980
11th to 20thNight
12%5%36%6%36%5%5%7%42%
1980
21st to endNight
9%6%36%5%35%5%6%7%45%
1980
October1st to 10thNight
11%5%25%434448%52%
1980
11th to 20thNight
11%424323346%58%
2074
21st to endNight
10%4245%24445%56%
2376
November1st to 10thNight
11%423424445%56%
2308
11th to 20thNight
14%423423346%56%
2470
21st to endNight
14%5%36%423446%49%
2470
December1st to 10thNight
14%5%25%43445%6%47%
2470
11th to 20thNight
16%6%25%424346%48%
3042
21st to endNight
18%9%36%5%3445%6%36%
4532

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 10thDay
40%5%6%18%23%10%
2837
11th to 20thDay
31%46%16%31%13%
2840
21st to endDay
44%5%5%13%22%12%
3317
February1st to 10thDay
44%5%8%15%19%9%
1900
11th to 20thDay
40%5%6%16%25%9%
1858
21st to endDay
40%5%9%15%19%11%
1570
March1st to 10thDay
36%5%8%17%21%13%
1952
11th to 20thDay
40%6%12%14%18%9%
1980
21st to endDay
37%6%11%18%22%6%
2178
April1st to 10thDay
38%6%8%20%18%10%
1980
11th to 20thDay
34%5%8%19%23%11%
2120
21st to endDay
26%6%10%25%26%7%
2286
May1st to 10thDay
27%7%11%22%26%7%
2340
11th to 20thDay
35%10%15%22%14%4
2305
21st to endDay
35%8%12%23%18%3
2531
June1st to 10thDay
43%11%15%17%12%1
2340
11th to 20thDay
32%12%17%23%15%1
2340
21st to endDay
38%12%19%17%11%2
2340
July1st to 10thDay
41%15%23%15%5%1
2275
11th to 20thDay
43%13%23%15%6%1
2271
21st to endDay
38%15%21%20%7%
2405
August1st to 10thDay
41%14%22%19%4
2314
11th to 20thDay
46%12%19%15%7%
2125
21st to endDay
47%12%17%13%8%2
2345
September1st to 10thDay
40%10%16%15%15%3
1980
11th to 20thDay
39%10%10%18%18%5%
1980
21st to endDay
41%7%8%18%19%7%
1980
October1st to 10thDay
33%5%10%18%23%10%
1980
11th to 20thDay
28%48%24%26%10%
1886
21st to endDay
30%5%7%13%29%17%
1980
November1st to 10thDay
32%47%16%26%16%
1767
11th to 20thDay
32%47%16%26%15%
1710
21st to endDay
37%6%8%16%23%10%
1710
December1st to 10thDay
42%6%10%13%19%9%
1710
11th to 20thDay
42%46%14%26%8%
2150
21st to endDay
45%46%16%24%5%
3124
January1st to 10thNight
38%6%7%15%22%10%
4109
11th to 20thNight
32%6%6%20%25%10%
4120
21st to endNight
46%5%5%11%24%9%
4336
February1st to 10thNight
40%48%16%20%12%
2280
11th to 20thNight
40%46%14%22%13%
2219
21st to endNight
38%6%8%15%17%15%
1884
March1st to 10thNight
34%5%7%18%22%14%
2169
11th to 20thNight
36%7%13%15%20%10%
1980
21st to endNight
34%6%11%18%23%9%
2178
April1st to 10thNight
33%7%10%18%18%13%
1980
11th to 20thNight
33%48%21%23%11%
1803
21st to endNight
24%6%11%25%24%9%
1672
May1st to 10thNight
25%8%12%22%25%8%
1620
11th to 20thNight
32%11%17%17%17%5%
1593
21st to endNight
32%9%13%23%18%4
1745
June1st to 10thNight
41%12%17%19%12%
1620
11th to 20thNight
29%11%21%26%12%1
1620
21st to endNight
35%14%21%15%12%3
1620
July1st to 10thNight
39%17%22%13%7%2
1575
11th to 20thNight
35%15%29%13%7%
1566
21st to endNight
32%15%25%21%6%1
1672
August1st to 10thNight
35%14%26%20%4
1600
11th to 20thNight
37%15%21%17%8%1
1772
21st to endNight
43%13%18%15%9%2
1991
September1st to 10thNight
40%11%16%15%14%4
1980
11th to 20thNight
40%9%13%16%18%4
1980
21st to endNight
36%8%13%15%22%6%
1980
October1st to 10thNight
32%6%9%20%22%12%
1980
11th to 20thNight
28%48%20%29%11%
2074
21st to endNight
30%46%16%27%16%
2376
November1st to 10thNight
31%5%7%14%27%16%
2308
11th to 20thNight
31%46%15%27%16%
2470
21st to endNight
37%5%6%19%22%11%
2470
December1st to 10thNight
38%5%10%18%22%7%
2470
11th to 20thNight
38%5%6%14%29%9%
3044
21st to endNight
48%5%6%17%20%4
4532

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 10thDay
13%18%45%20%4
270
11th to 20thDay
11%20%35%20%11%2
270
21st to endDay
22%18%43%12%5%1
297
February1st to 10thDay
19%17%38%21%6%
270
11th to 20thDay
26%15%33%22%4
270
21st to endDay
16%20%42%17%4
225
March1st to 10thDay
14%14%30%29%12%1
343
11th to 20thDay
16%9%38%25%11%1
420
21st to endDay
16%10%35%29%9%1
462
April1st to 10thDay
15%14%25%29%14%3
420
11th to 20thDay
14%9%31%23%18%5%
412
21st to endDay
9%8%23%31%24%6%
420
May1st to 10thDay
7%10%23%28%24%7%
423
11th to 20thDay
9%316%28%27%17%
447
21st to endDay
11%211%26%30%21%
485
June1st to 10thDay
12%110%26%32%19%
450
11th to 20thDay
8%212%18%29%30%
450
21st to endDay
6%39%24%31%27%
450
July1st to 10thDay
5%25%17%35%36%
445
11th to 20thDay
7%1317%30%42%
444
21st to endDay
6%418%38%33%
488
August1st to 10thDay
11%26%18%34%29%
446
11th to 20thDay
8%2415%39%32%
439
21st to endDay
11%47%22%31%25%
495
September1st to 10thDay
10%27%23%34%24%
450
11th to 20thDay
13%39%26%34%14%
450
21st to endDay
14%212%24%30%17%
450
October1st to 10thDay
14%222%31%20%11%
450
11th to 20thDay
10%6%16%30%27%10%
450
21st to endDay
11%7%24%28%23%5%
495
November1st to 10thDay
16%5%22%31%22%4
365
11th to 20thDay
14%11%36%27%10%2
270
21st to endDay
13%11%29%31%14%2
270
December1st to 10thDay
21%11%34%23%10%2
270
11th to 20thDay
22%13%33%21%10%1
270
21st to endDay
25%11%30%22%10%1
297
January1st to 10thNight
19%10%37%27%6%1
760
11th to 20thNight
16%9%32%32%11%
760
21st to endNight
19%11%37%29%4
836
February1st to 10thNight
17%8%33%34%7%
760
11th to 20thNight
22%9%33%31%6%
743
21st to endNight
17%10%37%32%4
628
March1st to 10thNight
13%9%33%38%7%
751
11th to 20thNight
15%8%34%31%13%1
720
21st to endNight
12%11%30%35%12%
792
April1st to 10thNight
13%8%30%33%16%
720
11th to 20thNight
15%7%26%35%17%1
561
21st to endNight
6%424%41%23%1
540
May1st to 10thNight
6%425%41%22%2
540
11th to 20thNight
8%320%37%28%4
531
21st to endNight
9%29%36%37%7%
584
June1st to 10thNight
9%210%36%37%5%
540
11th to 20thNight
337%33%43%12%
540
21st to endNight
6%17%32%45%9%
540
July1st to 10thNight
7%25%25%44%17%
525
11th to 20thNight
8%320%50%19%
522
21st to endNight
6%1425%52%13%
591
August1st to 10thNight
6%15%25%47%16%
537
11th to 20thNight
9%1421%51%13%
534
21st to endNight
13%16%24%41%14%
605
September1st to 10thNight
10%27%28%43%10%
720
11th to 20thNight
13%29%32%39%6%
720
21st to endNight
12%211%31%41%3
720
October1st to 10thNight
11%218%35%28%5%
720
11th to 20thNight
14%418%34%28%3
720
21st to endNight
12%423%35%24%2
792
November1st to 10thNight
13%5%20%38%21%2
740
11th to 20thNight
14%7%27%36%15%1
760
21st to endNight
16%6%30%31%16%1
760
December1st to 10thNight
16%7%29%33%14%1
760
11th to 20thNight
18%6%30%32%12%1
760
21st to endNight
24%10%23%34%9%
836
Page generated at 2024-03-05 07:23:59. Version ac07

Copyright © 2024 Attilla Danko.


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