Sea Rim State Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Sea Rim State Park clear sky chart from 2005-11-06 to 2024-01-13.

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
57%
23621
22%
74215
19%
23568
61%
23568
30%
44403

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
38%
949
24%
2458
11%
946
46%
946
28%
1646
January11th to 20thNight
41%
915
24%
2379
11%
915
48%
915
31%
1553
January21st to endNight
39%
990
23%
2574
11%
990
45%
990
27%
1761
February1st to 10thNight
37%
900
20%
2340
9%
900
43%
900
26%
1618
February11th to 20thNight
38%
618
20%
2013
14%
615
44%
615
23%
1278
February21st to endNight
34%
444
20%
1628
13%
444
42%
444
19%
1070
March1st to 10thNight
42%
540
23%
1980
17%
540
50%
540
25%
1194
March11th to 20thNight
43%
540
19%
1980
15%
540
49%
540
21%
1245
March21st to endNight
49%
594
24%
2178
21%
594
56%
594
28%
1230
April1st to 10thNight
46%
540
23%
1935
19%
540
55%
540
23%
1196
April11th to 20thNight
45%
533
24%
1775
18%
533
55%
533
28%
1050
April21st to endNight
51%
540
25%
1800
23%
540
59%
540
31%
1029
May1st to 10thNight
55%
540
21%
1800
21%
540
61%
540
31%
1022
May11th to 20thNight
64%
531
24%
1717
27%
531
67%
531
36%
945
May21st to endNight
72%
583
25%
1745
28%
582
73%
582
39%
979
June1st to 10thNight
81%
540
22%
1620
25%
540
81%
540
42%
864
June11th to 20thNight
81%
540
19%
1620
23%
540
81%
540
39%
888
June21st to endNight
72%
540
15%
1620
17%
540
72%
540
29%
1015
July1st to 10thNight
73%
525
15%
1575
19%
525
73%
525
31%
958
July11th to 20thNight
83%
522
18%
1566
22%
522
83%
522
37%
882
July21st to endNight
81%
591
15%
1673
18%
558
81%
558
37%
945
August1st to 10thNight
91%
537
21%
1622
24%
534
91%
534
52%
788
August11th to 20thNight
81%
534
19%
1776
23%
534
82%
534
34%
990
August21st to endNight
77%
594
15%
1980
18%
594
77%
594
30%
1182
September1st to 10thNight
74%
540
17%
1833
18%
540
74%
540
29%
1072
September11th to 20thNight
68%
540
18%
1980
21%
540
68%
540
24%
1229
September21st to endNight
73%
540
28%
1980
30%
540
74%
540
31%
1058
October1st to 10thNight
73%
710
29%
2150
26%
710
74%
710
42%
1153
October11th to 20thNight
66%
720
32%
2160
26%
720
71%
720
43%
1170
October21st to endNight
64%
792
34%
2376
27%
792
69%
792
42%
1280
November1st to 10thNight
66%
740
28%
2220
23%
740
69%
740
38%
1255
November11th to 20thNight
56%
760
31%
2280
24%
760
62%
760
35%
1330
November21st to endNight
46%
760
28%
2280
19%
760
54%
760
30%
1423
December1st to 10thNight
47%
855
25%
2375
16%
855
52%
855
29%
1528
December11th to 20thNight
42%
948
23%
2876
13%
948
46%
948
24%
1862
December21st to endNight
38%
1036
14%
4351
10%
1026
43%
1026
17%
2715

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%6%35%5%35%5%7%9%40%
75004
Night
12%6%25%4345%6%8%46%
74763
TransparencyDay
38%5%15%21%15%5%
74730
Night
36%5%13%21%17%7%
74558
SeeingDay
12%415%25%30%14%
13704
Night
13%417%29%28%8%
23634

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
18%7%35%6%2445%6%40%
1707
11th to 20thDay
15%6%445%33448%45%
1643
21st to endDay
19%8%26%5%3445%5%40%
1782
February1st to 10thDay
20%8%36%7%335%5%6%35%
1620
11th to 20thDay
22%8%47%42325%5%38%
1845
21st to endDay
22%10%37%5%24346%35%
1628
March1st to 10thDay
18%7%37%5%3445%7%37%
1980
11th to 20thDay
15%8%36%6%34446%41%
1980
21st to endDay
13%5%36%42445%7%46%
2178
April1st to 10thDay
13%7%35%5%45%45%9%38%
2024
11th to 20thDay
14%7%36%6%35%5%6%8%39%
2134
21st to endDay
9%5%25%5%35%5%5%9%47%
2160
May1st to 10thDay
10%5%26%6%36%6%7%10%40%
2160
11th to 20thDay
9%425%436%6%6%11%44%
2174
21st to endDay
7%5%36%5%48%7%8%13%34%
2531
June1st to 10thDay
5%4246%46%8%10%11%38%
2340
11th to 20thDay
5%426%6%5%7%7%9%13%38%
2340
21st to endDay
8%436%8%5%8%8%11%12%28%
2340
July1st to 10thDay
9%5%35%5%47%8%11%14%30%
2340
11th to 20thDay
7%425%7%46%8%10%13%34%
2340
21st to endDay
6%425%6%5%6%7%9%13%35%
2546
August1st to 10thDay
43146%47%8%10%15%39%
2305
11th to 20thDay
5%425%6%46%10%11%13%33%
2125
21st to endDay
10%426%6%46%7%8%12%34%
2376
September1st to 10thDay
8%5%37%7%45%7%8%11%35%
2121
11th to 20thDay
14%7%36%6%46%6%6%8%35%
1980
21st to endDay
9%6%24435%5%7%9%45%
1970
October1st to 10thDay
6%424435%46%9%54%
1800
11th to 20thDay
11%32343446%7%53%
1800
21st to endDay
13%424423346%55%
1980
November1st to 10thDay
10%5%335%3445%7%51%
1858
11th to 20thDay
12%5%25%4245%5%7%49%
1900
21st to endDay
15%6%36%43445%6%44%
1900
December1st to 10thDay
15%6%36%5%24347%44%
1801
11th to 20thDay
14%7%36%5%45%5%5%6%40%
2161
21st to endDay
16%7%25%5%345%5%6%42%
3135
January1st to 10thNight
17%8%35%5%24346%43%
2458
11th to 20thNight
18%5%35%423345%47%
2379
21st to endNight
18%7%36%5%34445%41%
2574
February1st to 10thNight
18%7%46%5%34446%39%
2340
11th to 20thNight
19%8%35%432446%42%
2013
21st to endNight
20%9%35%42445%7%36%
1628
March1st to 10thNight
15%7%35%43346%7%42%
1980
11th to 20thNight
16%8%36%5%245%5%7%40%
1980
21st to endNight
13%6%25%434447%49%
2178
April1st to 10thNight
15%7%35%435%5%5%8%41%
1935
11th to 20thNight
15%425%3335%6%7%46%
1775
21st to endNight
11%435%435%46%8%47%
1800
May1st to 10thNight
11%5%26%5%3447%10%44%
1800
11th to 20thNight
8%4245%345%6%9%50%
1716
21st to endNight
6%4244346%7%12%47%
1745
June1st to 10thNight
5%3244345%6%11%54%
1620
11th to 20thNight
43245%35%6%8%14%47%
1620
21st to endNight
6%6%26%6%46%5%9%13%38%
1620
July1st to 10thNight
7%6%35%5%35%6%7%12%41%
1620
11th to 20thNight
33245%35%6%8%12%49%
1620
21st to endNight
3334426%7%8%13%46%
1772
August1st to 10thNight
21123246%7%13%59%
1632
11th to 20thNight
43245%35%6%9%15%45%
1776
21st to endNight
8%425%5%35%6%8%12%41%
1980
September1st to 10thNight
7%425%6%345%6%11%45%
1833
11th to 20thNight
11%6%36%6%346%7%9%39%
1980
21st to endNight
9%425%42446%8%53%
1980
October1st to 10thNight
6%5%2442445%8%58%
2150
11th to 20thNight
9%42342335%8%57%
2160
21st to endNight
11%424323346%59%
2376
November1st to 10thNight
8%5%25%42445%7%54%
2220
11th to 20thNight
13%425%423346%54%
2280
21st to endNight
13%6%36%5%245%5%6%46%
2280
December1st to 10thNight
16%8%26%5%33447%43%
2375
11th to 20thNight
15%8%35%43445%6%42%
3036
21st to endNight
17%7%36%5%3445%5%42%
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
46%35%18%20%7%
1708
11th to 20thDay
40%47%19%21%9%
1643
21st to endDay
46%36%17%17%12%
1782
February1st to 10thDay
51%36%15%16%9%
1620
11th to 20thDay
52%37%13%17%8%
1856
21st to endDay
54%47%14%15%7%
1628
March1st to 10thDay
47%5%9%17%17%5%
1980
11th to 20thDay
45%411%13%19%8%
1980
21st to endDay
39%415%16%22%5%
2178
April1st to 10thDay
43%412%18%15%8%
2024
11th to 20thDay
43%412%19%15%8%
2134
21st to endDay
33%415%22%21%5%
2160
May1st to 10thDay
36%417%21%17%6%
2160
11th to 20thDay
34%5%14%30%15%3
2178
21st to endDay
32%8%20%29%11%1
2531
June1st to 10thDay
31%7%21%27%14%
2340
11th to 20thDay
31%7%20%30%11%1
2340
21st to endDay
40%8%24%22%7%
2340
July1st to 10thDay
35%9%29%24%4
2276
11th to 20thDay
34%11%28%24%4
2271
21st to endDay
33%8%31%24%31
2405
August1st to 10thDay
26%8%28%32%6%
2291
11th to 20thDay
34%11%25%24%5%1
2125
21st to endDay
38%8%23%22%6%2
2376
September1st to 10thDay
37%10%19%17%13%3
2121
11th to 20thDay
44%7%15%18%14%3
1980
21st to endDay
33%5%15%24%15%7%
1970
October1st to 10thDay
27%411%27%22%10%
1800
11th to 20thDay
30%49%22%25%11%
1800
21st to endDay
31%38%19%25%15%
1980
November1st to 10thDay
34%410%24%20%8%
1858
11th to 20thDay
34%411%20%21%10%
1900
21st to endDay
42%48%20%19%8%
1900
December1st to 10thDay
41%311%23%15%7%
1801
11th to 20thDay
45%38%18%18%9%
2159
21st to endDay
44%27%17%22%8%
3135
January1st to 10thNight
44%36%16%22%9%
2458
11th to 20thNight
40%35%19%20%12%
2379
21st to endNight
46%35%16%17%12%
2574
February1st to 10thNight
47%37%12%20%10%
2340
11th to 20thNight
44%47%18%18%9%
2013
21st to endNight
47%5%9%13%14%11%
1628
March1st to 10thNight
41%412%17%17%9%
1980
11th to 20thNight
44%5%13%14%17%7%
1980
21st to endNight
36%412%20%21%8%
2178
April1st to 10thNight
43%410%19%16%9%
1935
11th to 20thNight
39%311%22%14%11%
1775
21st to endNight
35%411%22%21%7%
1800
May1st to 10thNight
34%414%23%16%8%
1800
11th to 20thNight
29%6%12%28%22%3
1717
21st to endNight
27%7%18%31%15%2
1746
June1st to 10thNight
25%6%20%34%15%
1620
11th to 20thNight
26%7%19%32%15%1
1620
21st to endNight
37%7%24%24%7%
1620
July1st to 10thNight
34%7%28%27%3
1575
11th to 20thNight
27%8%33%27%5%
1566
21st to endNight
27%9%31%29%4
1673
August1st to 10thNight
17%6%32%36%8%
1622
11th to 20thNight
27%9%29%28%6%
1776
21st to endNight
33%9%26%23%7%2
1980
September1st to 10thNight
33%8%22%20%13%3
1833
11th to 20thNight
41%6%17%18%14%4
1980
21st to endNight
31%5%14%23%20%7%
1980
October1st to 10thNight
27%39%26%22%12%
2150
11th to 20thNight
26%49%25%22%13%
2160
21st to endNight
29%27%18%28%17%
2376
November1st to 10thNight
31%411%23%23%9%
2220
11th to 20thNight
34%38%20%26%9%
2280
21st to endNight
40%39%21%19%8%
2280
December1st to 10thNight
42%310%22%15%8%
2375
11th to 20thNight
43%37%15%18%14%
3037
21st to endNight
47%26%15%22%8%
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
22%9%31%27%11%
270
11th to 20thDay
14%10%29%33%13%1
248
21st to endDay
19%9%35%29%7%1
264
February1st to 10thDay
25%5%33%27%9%
240
11th to 20thDay
27%10%30%27%6%
240
21st to endDay
22%8%38%27%5%
198
March1st to 10thDay
19%5%39%30%7%
240
11th to 20thDay
18%11%40%23%6%2
240
21st to endDay
13%12%31%34%9%1
264
April1st to 10thDay
12%10%31%36%11%
284
11th to 20thDay
19%8%29%23%19%1
412
21st to endDay
11%6%24%39%18%2
420
May1st to 10thDay
13%5%23%34%21%4
423
11th to 20thDay
11%315%37%29%5%
497
21st to endDay
8%312%38%33%6%
679
June1st to 10thDay
7%16%32%38%15%
630
11th to 20thDay
8%17%27%42%14%
630
21st to endDay
10%15%22%41%20%
630
July1st to 10thDay
6%2417%44%26%
621
11th to 20thDay
6%1115%44%33%
618
21st to endDay
5%1315%47%29%
684
August1st to 10thDay
31110%52%32%
603
11th to 20thDay
6%137%41%43%
439
21st to endDay
13%2312%35%36%
495
September1st to 10thDay
9%414%45%28%
411
11th to 20thDay
14%15%15%38%27%
270
21st to endDay
13%1417%44%20%
270
October1st to 10thDay
7%26%28%41%16%
270
11th to 20thDay
12%310%30%33%13%
270
21st to endDay
16%7%19%27%27%5%
297
November1st to 10thDay
13%315%32%32%6%
270
11th to 20thDay
15%6%19%38%17%5%
270
21st to endDay
17%7%30%29%15%3
270
December1st to 10thDay
17%7%19%30%20%7%
270
11th to 20thDay
18%7%28%37%10%
270
21st to endDay
21%8%29%27%13%2
297
January1st to 10thNight
20%7%27%35%10%
950
11th to 20thNight
20%7%26%36%10%1
915
21st to endNight
21%6%28%36%9%
990
February1st to 10thNight
21%6%30%35%8%
900
11th to 20thNight
23%11%24%31%11%
618
21st to endNight
22%8%30%33%7%
444
March1st to 10thNight
18%7%29%33%13%
540
11th to 20thNight
18%7%24%36%13%1
540
21st to endNight
12%6%27%38%16%1
594
April1st to 10thNight
17%7%24%37%15%
540
11th to 20thNight
16%7%24%36%16%
533
21st to endNight
12%5%26%39%17%1
540
May1st to 10thNight
10%6%23%42%18%
540
11th to 20thNight
9%218%42%26%2
531
21st to endNight
6%211%37%38%6%
584
June1st to 10thNight
5%1330%51%10%
540
11th to 20thNight
415%25%53%12%
540
21st to endNight
7%16%17%51%19%
540
July1st to 10thNight
6%2412%49%27%
525
11th to 20thNight
3129%48%38%
522
21st to endNight
2139%58%27%
591
August1st to 10thNight
2115%57%35%
537
11th to 20thNight
5%27%53%34%
534
21st to endNight
9%1215%49%24%
594
September1st to 10thNight
8%1413%49%25%
540
11th to 20thNight
10%2418%51%15%
540
21st to endNight
12%16%21%48%13%
540
October1st to 10thNight
6%38%26%49%8%
710
11th to 20thNight
9%216%31%35%7%
720
21st to endNight
12%5%15%34%30%4
792
November1st to 10thNight
10%316%34%32%5%
740
11th to 20thNight
15%5%18%37%24%1
760
21st to endNight
14%428%34%17%3
760
December1st to 10thNight
19%6%22%33%20%1
855
11th to 20thNight
19%8%25%34%14%
950
21st to endNight
21%7%26%33%12%
1045
Page generated at 2024-01-10 18:35:24. Version ac07

Copyright 2024 Attilla Danko


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