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Carr's Mill Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Carr's Mill Park clear sky chart from 2005-11-06 to 2024-01-16.

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
36%
23407
21%
74694
11%
23356
48%
23356
24%
46483

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
17%
757
24%
2630
7%
757
39%
757
19%
1596
January11th to 20thNight
22%
741
22%
2406
8%
741
39%
741
18%
1522
January21st to endNight
19%
792
25%
2574
8%
792
40%
792
21%
1583
February1st to 10thNight
21%
720
18%
2340
7%
720
36%
720
19%
1491
February11th to 20thNight
14%
702
20%
2221
3%
700
34%
700
18%
1412
February21st to endNight
15%
592
24%
1776
6%
592
36%
592
19%
1188
March1st to 10thNight
22%
720
24%
2028
8%
720
39%
720
25%
1257
March11th to 20thNight
23%
720
21%
1980
8%
720
37%
720
22%
1303
March21st to endNight
21%
792
21%
2136
7%
792
33%
792
24%
1424
April1st to 10thNight
22%
720
19%
1800
4%
720
31%
720
24%
1233
April11th to 20thNight
35%
711
20%
1775
6%
711
42%
711
29%
1177
April21st to endNight
31%
720
20%
1800
6%
720
38%
720
28%
1212
May1st to 10thNight
37%
595
18%
1675
10%
595
42%
595
25%
1113
May11th to 20thNight
37%
393
18%
1454
11%
393
47%
393
20%
920
May21st to endNight
52%
388
16%
1551
14%
388
58%
388
23%
911
June1st to 10thNight
52%
360
21%
1440
21%
360
61%
360
25%
810
June11th to 20thNight
53%
360
16%
1440
18%
360
58%
360
21%
878
June21st to endNight
60%
360
18%
1440
18%
360
66%
360
26%
796
July1st to 10thNight
61%
350
14%
1400
18%
350
64%
350
20%
877
July11th to 20thNight
70%
384
17%
1428
18%
384
73%
384
29%
801
July21st to endNight
67%
591
18%
1672
14%
558
71%
558
34%
990
August1st to 10thNight
64%
537
16%
1600
13%
534
66%
534
29%
1032
August11th to 20thNight
60%
609
17%
1673
11%
609
62%
609
28%
1124
August21st to endNight
63%
792
20%
1980
12%
792
64%
792
35%
1295
September1st to 10thNight
55%
720
23%
1800
11%
720
60%
720
33%
1198
September11th to 20thNight
60%
720
31%
1800
22%
720
64%
720
39%
1115
September21st to endNight
46%
720
22%
2058
16%
720
53%
720
26%
1370
October1st to 10thNight
47%
720
19%
2160
17%
720
54%
720
27%
1384
October11th to 20thNight
42%
720
26%
2160
19%
720
54%
720
31%
1279
October21st to endNight
35%
792
27%
2376
16%
792
50%
792
29%
1433
November1st to 10thNight
39%
740
28%
2339
16%
740
54%
740
32%
1326
November11th to 20thNight
31%
760
25%
2490
13%
760
47%
760
24%
1477
November21st to endNight
30%
760
23%
2660
12%
760
47%
760
23%
1543
December1st to 10thNight
23%
760
19%
2660
6%
760
40%
760
18%
1683
December11th to 20thNight
22%
760
21%
3174
8%
759
39%
759
18%
1909
December21st to endNight
24%
829
15%
4798
9%
817
40%
817
12%
2821

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
14%6%35%5%35%5%6%8%42%
74714
Night
14%6%25%5%345%5%7%43%
75086
TransparencyDay
40%6%12%23%16%3
74424
Night
39%5%12%24%17%3
74895
SeeingDay
19%11%27%24%14%5%
13829
Night
18%10%29%29%12%1
23419

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
14%7%27%5%35%6%46%42%
1532
11th to 20thDay
15%8%36%434447%41%
1665
21st to endDay
14%8%46%5%45%446%40%
1782
February1st to 10thDay
14%7%36%7%35%5%6%6%37%
1620
11th to 20thDay
17%7%26%5%345%5%6%39%
1625
21st to endDay
19%8%45%5%34345%40%
1480
March1st to 10thDay
12%6%35%434447%48%
1930
11th to 20thDay
16%7%35%5%3445%6%42%
1980
21st to endDay
17%6%36%5%36%5%46%39%
2218
April1st to 10thDay
12%7%35%5%345%6%8%41%
2160
11th to 20thDay
14%5%36%5%23446%47%
2134
21st to endDay
18%6%345%345%5%7%41%
2160
May1st to 10thDay
16%6%36%5%345%6%9%38%
2299
11th to 20thDay
19%6%35%5%35%5%5%8%36%
2437
21st to endDay
13%5%26%6%3446%8%41%
2725
June1st to 10thDay
12%425%5%35%47%10%41%
2520
11th to 20thDay
11%6%26%6%45%6%6%8%39%
2520
21st to endDay
10%424436%5%7%10%45%
2520
July1st to 10thDay
9%5%35%6%45%5%6%8%44%
2520
11th to 20thDay
6%4245%36%7%8%10%44%
2480
21st to endDay
11%6%25%6%46%7%7%9%37%
2547
August1st to 10thDay
10%5%25%7%46%7%8%9%37%
2327
11th to 20thDay
12%5%35%6%45%5%6%8%40%
2210
21st to endDay
11%5%245%36%6%5%9%42%
2376
September1st to 10thDay
15%6%245%3445%8%45%
2160
11th to 20thDay
12%5%25%435%36%8%47%
2160
21st to endDay
18%7%35%5%25%46%7%39%
1899
October1st to 10thDay
17%5%26%43345%7%45%
1800
11th to 20thDay
18%5%244245%5%6%47%
1800
21st to endDay
14%5%25%5%3445%6%46%
1980
November1st to 10thDay
12%5%3432436%7%51%
1739
11th to 20thDay
15%42433446%6%49%
1687
21st to endDay
16%5%25%435%45%5%47%
1520
December1st to 10thDay
17%6%25%4445%6%8%39%
1520
11th to 20thDay
16%6%35%5%3445%8%42%
1910
21st to endDay
17%7%35%5%35%5%5%8%36%
2772
January1st to 10thNight
15%6%35%5%3445%7%44%
2630
11th to 20thNight
17%7%35%5%35%5%5%7%40%
2406
21st to endNight
14%7%24435%45%6%45%
2574
February1st to 10thNight
15%8%26%5%345%5%7%40%
2340
11th to 20thNight
18%7%36%424447%42%
2219
21st to endNight
17%7%36%5%3445%5%41%
1776
March1st to 10thNight
13%5%244345%5%6%48%
2028
11th to 20thNight
17%6%35%43445%7%43%
1980
21st to endNight
14%8%36%4345%47%41%
2136
April1st to 10thNight
15%6%446%35%5%5%7%40%
1800
11th to 20thNight
13%5%26%5%25%45%7%45%
1775
21st to endNight
17%5%35%4345%6%8%42%
1800
May1st to 10thNight
16%7%35%5%3447%8%39%
1675
11th to 20thNight
18%8%344245%6%8%38%
1454
21st to endNight
12%6%245%25%5%7%11%40%
1550
June1st to 10thNight
11%4344345%8%9%44%
1440
11th to 20thNight
11%5%37%5%35%6%6%9%40%
1440
21st to endNight
9%5%245%36%5%7%10%44%
1440
July1st to 10thNight
9%5%37%7%47%6%6%9%38%
1440
11th to 20thNight
6%4146%46%6%7%9%46%
1476
21st to endNight
8%424445%6%8%13%43%
1771
August1st to 10thNight
9%5%26%5%36%7%8%9%39%
1611
11th to 20thNight
11%5%27%6%35%6%6%6%41%
1673
21st to endNight
11%435%5%45%6%6%10%43%
1980
September1st to 10thNight
15%5%35%4245%47%46%
1800
11th to 20thNight
10%6%35%5%33348%52%
1800
21st to endNight
17%5%25%5%345%46%41%
2058
October1st to 10thNight
19%6%3433445%5%45%
2160
11th to 20thNight
16%425%42335%6%51%
2160
21st to endNight
15%6%2442445%7%48%
2376
November1st to 10thNight
12%5%2442435%6%53%
2339
11th to 20thNight
14%6%25%423445%49%
2490
21st to endNight
14%4245%35%46%7%47%
2660
December1st to 10thNight
16%8%36%5%35%45%7%40%
2660
11th to 20thNight
17%5%25%5%345%5%6%43%
3285
21st to endNight
15%7%25%6%45%6%6%9%36%
4884

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
42%5%11%24%14%3
1533
11th to 20thDay
43%5%12%24%13%3
1665
21st to endDay
46%410%21%14%4
1782
February1st to 10thDay
45%5%13%25%11%2
1620
11th to 20thDay
45%49%26%14%3
1634
21st to endDay
47%410%20%14%4
1480
March1st to 10thDay
37%412%25%19%2
1930
11th to 20thDay
43%5%11%19%17%5%
1980
21st to endDay
47%5%8%19%17%3
2218
April1st to 10thDay
39%6%12%22%17%5%
2160
11th to 20thDay
38%5%10%22%19%5%
2134
21st to endDay
42%5%11%21%18%4
2160
May1st to 10thDay
43%6%13%21%16%2
2299
11th to 20thDay
46%6%13%19%14%2
2441
21st to endDay
40%7%15%24%12%2
2725
June1st to 10thDay
37%7%14%25%15%1
2520
11th to 20thDay
40%9%12%23%13%2
2520
21st to endDay
33%7%16%26%17%1
2520
July1st to 10thDay
38%7%14%22%16%3
2450
11th to 20thDay
31%8%15%28%16%3
2405
21st to endDay
39%9%13%21%15%2
2405
August1st to 10thDay
39%9%14%25%12%1
2314
11th to 20thDay
40%6%14%22%16%2
2210
21st to endDay
38%6%15%24%15%3
2376
September1st to 10thDay
38%6%13%22%17%4
2160
11th to 20thDay
35%49%27%21%4
2160
21st to endDay
44%5%8%21%19%2
1899
October1st to 10thDay
40%5%10%25%18%3
1800
11th to 20thDay
38%5%10%23%21%3
1800
21st to endDay
38%49%27%20%2
1980
November1st to 10thDay
33%313%26%20%4
1739
11th to 20thDay
36%410%24%23%4
1687
21st to endDay
39%411%29%16%2
1520
December1st to 10thDay
43%6%13%24%12%2
1520
11th to 20thDay
39%6%11%31%11%2
1906
21st to endDay
45%6%15%23%11%1
2772
January1st to 10thNight
40%5%9%25%17%4
2630
11th to 20thNight
43%5%14%23%14%1
2406
21st to endNight
39%5%9%27%18%3
2574
February1st to 10thNight
43%5%13%24%13%2
2340
11th to 20thNight
43%310%22%18%4
2221
21st to endNight
45%49%22%15%5%
1776
March1st to 10thNight
36%411%27%18%3
2028
11th to 20thNight
41%6%11%21%18%4
1980
21st to endNight
42%5%11%20%16%5%
2136
April1st to 10thNight
41%6%10%20%19%4
1800
11th to 20thNight
38%5%11%21%19%6%
1775
21st to endNight
39%7%10%24%15%5%
1800
May1st to 10thNight
43%5%12%23%13%4
1675
11th to 20thNight
44%5%12%18%18%2
1455
21st to endNight
37%8%19%22%12%2
1551
June1st to 10thNight
34%8%11%28%17%2
1440
11th to 20thNight
39%9%13%23%14%2
1440
21st to endNight
35%6%14%25%18%2
1440
July1st to 10thNight
42%8%17%18%13%3
1400
11th to 20thNight
30%9%15%27%15%3
1428
21st to endNight
31%8%19%24%16%2
1672
August1st to 10thNight
36%9%17%22%15%1
1600
11th to 20thNight
41%7%14%22%15%2
1673
21st to endNight
36%6%14%25%15%4
1980
September1st to 10thNight
38%6%12%21%19%5%
1800
11th to 20thNight
33%410%26%23%3
1800
21st to endNight
43%5%10%20%19%3
2058
October1st to 10thNight
41%5%11%23%17%3
2160
11th to 20thNight
35%49%29%20%2
2160
21st to endNight
36%410%26%21%3
2376
November1st to 10thNight
33%410%27%21%5%
2339
11th to 20thNight
38%48%24%21%5%
2490
21st to endNight
37%412%26%19%3
2660
December1st to 10thNight
44%5%11%25%13%2
2660
11th to 20thNight
42%411%22%18%3
3288
21st to endNight
43%6%16%23%11%1
4884

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
30%20%30%14%41
187
11th to 20thDay
27%24%31%15%3
255
21st to endDay
27%23%33%14%31
264
February1st to 10thDay
25%20%40%10%4
240
11th to 20thDay
31%20%42%6%
292
21st to endDay
32%20%30%16%2
346
March1st to 10thDay
21%24%31%21%4
420
11th to 20thDay
27%18%31%18%42
420
21st to endDay
23%19%32%19%5%1
462
April1st to 10thDay
21%18%36%18%6%2
420
11th to 20thDay
17%16%33%16%13%5%
412
21st to endDay
25%12%33%20%8%2
420
May1st to 10thDay
24%14%29%19%9%4
423
11th to 20thDay
23%10%27%26%12%3
447
21st to endDay
18%5%21%27%24%7%
485
June1st to 10thDay
14%8%26%26%18%8%
450
11th to 20thDay
17%8%24%26%20%6%
450
21st to endDay
11%424%36%19%6%
450
July1st to 10thDay
13%417%30%24%13%
445
11th to 20thDay
5%318%32%30%11%
444
21st to endDay
12%420%30%27%8%
488
August1st to 10thDay
12%217%30%28%11%
446
11th to 20thDay
13%316%30%26%12%
439
21st to endDay
10%220%31%22%15%
495
September1st to 10thDay
17%5%19%23%22%15%
450
11th to 20thDay
12%419%30%22%12%
450
21st to endDay
21%10%20%30%14%5%
450
October1st to 10thDay
22%6%22%23%20%7%
450
11th to 20thDay
18%11%27%27%14%2
450
21st to endDay
18%10%36%25%8%2
495
November1st to 10thDay
16%10%32%25%14%3
399
11th to 20thDay
20%14%32%22%11%1
347
21st to endDay
25%16%34%18%7%
180
December1st to 10thDay
23%16%40%14%42
180
11th to 20thDay
27%19%29%19%6%
180
21st to endDay
26%13%36%20%6%
198
January1st to 10thNight
19%19%41%19%3
760
11th to 20thNight
23%17%33%24%4
741
21st to endNight
19%18%40%21%2
792
February1st to 10thNight
20%16%38%24%2
720
11th to 20thNight
24%20%37%17%1
703
21st to endNight
24%18%39%16%2
592
March1st to 10thNight
19%16%39%23%3
720
11th to 20thNight
22%17%34%22%5%1
720
21st to endNight
19%14%41%21%41
792
April1st to 10thNight
20%16%38%22%4
720
11th to 20thNight
15%14%32%31%8%1
711
21st to endNight
21%9%35%27%8%1
720
May1st to 10thNight
20%7%30%30%12%1
595
11th to 20thNight
22%7%28%32%11%1
393
21st to endNight
16%321%37%19%3
389
June1st to 10thNight
13%324%37%23%1
360
11th to 20thNight
13%420%40%22%1
360
21st to endNight
11%119%50%19%1
360
July1st to 10thNight
8%315%43%28%3
350
11th to 20thNight
6%113%41%36%3
384
21st to endNight
8%215%45%26%4
591
August1st to 10thNight
11%210%42%32%3
537
11th to 20thNight
13%412%40%27%4
609
21st to endNight
12%214%39%28%5%
792
September1st to 10thNight
16%317%35%26%4
720
11th to 20thNight
11%314%37%30%5%
720
21st to endNight
20%5%20%34%19%2
720
October1st to 10thNight
22%5%20%31%19%4
720
11th to 20thNight
17%8%28%33%13%1
720
21st to endNight
20%9%32%27%11%
792
November1st to 10thNight
16%7%32%34%10%2
740
11th to 20thNight
17%16%31%29%7%1
760
21st to endNight
16%15%33%28%8%
760
December1st to 10thNight
22%14%35%22%7%1
760
11th to 20thNight
17%11%44%23%5%
760
21st to endNight
20%13%38%28%2
836
Page generated at 2024-01-13 01:38:12. Version ac07

Copyright 2024 Attilla Danko


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