Mount Mitchell
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Mount Mitchell clear sky chart from 2005-11-06 to 2024-01-12.

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
40%
24066
20%
74405
11%
24008
49%
24008
21%
47916

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
21%
760
21%
2459
7%
757
38%
757
17%
1530
January11th to 20thNight
23%
728
21%
2365
10%
728
38%
728
15%
1541
January21st to endNight
21%
792
25%
2574
8%
792
42%
792
18%
1557
February1st to 10thNight
26%
720
21%
2286
10%
720
38%
720
20%
1413
February11th to 20thNight
17%
702
20%
2098
5%
699
31%
699
15%
1368
February21st to endNight
18%
592
21%
1776
7%
592
31%
592
17%
1183
March1st to 10thNight
23%
720
24%
2012
9%
720
36%
720
21%
1277
March11th to 20thNight
24%
720
17%
1980
6%
720
34%
720
18%
1365
March21st to endNight
24%
792
15%
2178
6%
792
31%
792
19%
1489
April1st to 10thNight
29%
720
21%
1980
7%
720
41%
720
24%
1237
April11th to 20thNight
34%
641
23%
1773
9%
641
45%
641
25%
1116
April21st to endNight
42%
540
23%
1620
13%
540
51%
540
25%
1008
May1st to 10thNight
35%
540
15%
1620
6%
540
43%
540
22%
1054
May11th to 20thNight
43%
531
13%
1593
7%
531
47%
531
19%
1109
May21st to endNight
54%
582
14%
1745
10%
582
56%
582
24%
1155
June1st to 10thNight
56%
540
12%
1620
9%
540
58%
540
23%
1107
June11th to 20thNight
59%
540
12%
1620
7%
540
63%
540
28%
1043
June21st to endNight
62%
540
15%
1620
11%
540
65%
540
27%
1044
July1st to 10thNight
64%
525
11%
1575
9%
525
65%
525
23%
1097
July11th to 20thNight
64%
522
10%
1566
7%
522
66%
522
22%
1086
July21st to endNight
67%
591
12%
1672
10%
558
70%
558
23%
1168
August1st to 10thNight
62%
537
11%
1600
8%
534
64%
534
23%
1119
August11th to 20thNight
60%
534
16%
1598
13%
534
62%
534
22%
1128
August21st to endNight
61%
653
15%
1922
13%
653
63%
653
23%
1347
September1st to 10thNight
57%
720
19%
1980
15%
720
58%
720
23%
1378
September11th to 20thNight
50%
720
19%
1980
15%
720
53%
720
22%
1404
September21st to endNight
49%
720
22%
1980
16%
720
55%
720
26%
1316
October1st to 10thNight
46%
720
22%
2026
17%
720
53%
720
25%
1338
October11th to 20thNight
38%
720
25%
2160
16%
720
50%
720
25%
1337
October21st to endNight
42%
792
30%
2376
20%
792
56%
792
30%
1358
November1st to 10thNight
42%
740
27%
2289
17%
740
55%
740
28%
1343
November11th to 20thNight
39%
760
27%
2470
18%
760
53%
760
26%
1424
November21st to endNight
38%
760
26%
2470
15%
760
52%
760
23%
1460
December1st to 10thNight
26%
760
21%
2470
9%
760
40%
760
15%
1644
December11th to 20thNight
30%
760
25%
2954
14%
759
45%
759
18%
1742
December21st to endNight
27%
832
14%
4398
10%
817
40%
817
10%
2631

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
15%7%36%6%45%5%6%8%37%
74901
Night
14%6%35%5%35%5%6%8%41%
74834
TransparencyDay
44%7%12%19%14%4
74624
Night
40%7%13%21%16%4
74630
SeeingDay
22%14%24%21%13%7%
13946
Night
19%13%21%26%17%3
24073

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%8%245%3445%7%44%
1706
11th to 20thDay
15%9%35%5%2445%7%42%
1635
21st to endDay
15%7%14435%5%46%47%
1782
February1st to 10thDay
14%7%35%6%35%5%5%8%39%
1672
11th to 20thDay
17%8%36%5%35%446%41%
1748
21st to endDay
16%8%36%6%445%5%5%39%
1480
March1st to 10thDay
13%5%35%3345%6%6%47%
1947
11th to 20thDay
17%7%36%5%35%5%6%7%35%
1980
21st to endDay
18%8%36%5%35%46%7%34%
2178
April1st to 10thDay
11%5%34436%6%6%9%42%
1980
11th to 20thDay
16%6%35%425%46%8%40%
2149
21st to endDay
15%6%26%5%35%5%5%7%43%
2340
May1st to 10thDay
13%6%35%7%45%6%6%7%38%
2340
11th to 20thDay
19%7%27%7%46%6%5%7%30%
2301
21st to endDay
15%6%25%7%46%6%7%9%32%
2531
June1st to 10thDay
13%7%27%7%5%7%6%6%9%30%
2340
11th to 20thDay
10%5%48%8%5%7%7%6%10%31%
2340
21st to endDay
10%6%37%7%5%7%6%7%9%32%
2340
July1st to 10thDay
13%7%48%8%5%8%7%7%10%24%
2340
11th to 20thDay
13%7%37%8%5%8%8%9%9%23%
2340
21st to endDay
11%7%48%9%5%8%7%8%9%24%
2547
August1st to 10thDay
16%7%47%8%5%8%6%9%8%22%
2327
11th to 20thDay
15%7%37%9%5%6%7%7%9%24%
2303
21st to endDay
14%7%38%6%5%7%6%7%8%28%
2410
September1st to 10thDay
14%8%46%7%46%6%7%7%32%
1980
11th to 20thDay
20%7%35%6%36%6%6%8%30%
1980
21st to endDay
18%7%36%5%35%5%6%6%37%
1980
October1st to 10thDay
17%6%25%424446%46%
1932
11th to 20thDay
13%6%23424347%51%
1800
21st to endDay
16%423423446%53%
1980
November1st to 10thDay
11%6%23424246%55%
1786
11th to 20thDay
12%5%245%3345%7%50%
1710
21st to endDay
14%5%25%433448%48%
1710
December1st to 10thDay
17%8%37%6%45%45%6%36%
1710
11th to 20thDay
14%5%2343446%8%47%
2153
21st to endDay
19%6%435%3445%7%41%
3124
January1st to 10thNight
14%5%26%5%35%45%7%44%
2459
11th to 20thNight
15%7%36%5%45%45%7%40%
2365
21st to endNight
13%6%34445%45%6%46%
2574
February1st to 10thNight
13%6%245%345%6%8%43%
2286
11th to 20thNight
16%7%35%5%35%446%42%
2098
21st to endNight
15%7%45%5%35%5%5%8%37%
1776
March1st to 10thNight
11%7%25%6%345%5%7%45%
2012
11th to 20thNight
14%8%35%5%45%5%6%9%36%
1980
21st to endNight
16%8%26%6%345%6%8%38%
2178
April1st to 10thNight
11%6%35%43447%7%46%
1980
11th to 20thNight
15%6%2433445%8%47%
1773
21st to endNight
13%6%24434446%48%
1620
May1st to 10thNight
13%7%25%5%345%6%9%40%
1620
11th to 20thNight
17%5%27%5%45%5%5%8%36%
1592
21st to endNight
14%6%25%6%35%5%7%11%37%
1744
June1st to 10thNight
12%7%25%5%46%7%7%12%33%
1620
11th to 20thNight
10%435%436%5%7%10%41%
1620
21st to endNight
8%426%5%46%6%7%11%40%
1620
July1st to 10thNight
11%7%26%6%46%6%7%9%36%
1620
11th to 20thNight
10%5%25%5%47%7%8%12%34%
1620
21st to endNight
6%436%7%5%7%8%10%11%33%
1771
August1st to 10thNight
13%6%36%5%35%7%7%9%36%
1611
11th to 20thNight
14%6%27%5%45%5%6%9%36%
1598
21st to endNight
13%6%35%6%46%6%6%9%34%
1922
September1st to 10thNight
12%9%36%5%46%46%8%39%
1980
11th to 20thNight
19%9%25%6%3445%7%36%
1980
21st to endNight
19%7%25%424335%45%
1980
October1st to 10thNight
18%7%24424446%46%
2026
11th to 20thNight
15%7%3343435%6%48%
2160
21st to endNight
15%5%14323346%54%
2376
November1st to 10thNight
14%5%2442445%5%51%
2289
11th to 20thNight
13%6%23425%45%7%49%
2470
21st to endNight
13%5%25%4345%6%6%47%
2470
December1st to 10thNight
16%7%36%5%45%5%6%6%38%
2470
11th to 20thNight
12%7%36%43445%6%46%
3042
21st to endNight
21%6%45%445%45%7%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
39%5%10%23%17%5%
1707
11th to 20thDay
43%5%8%22%17%5%
1635
21st to endDay
38%48%24%21%5%
1782
February1st to 10thDay
43%5%12%20%16%4
1672
11th to 20thDay
46%411%19%16%4
1758
21st to endDay
45%6%9%17%16%6%
1480
March1st to 10thDay
37%410%22%20%7%
1947
11th to 20thDay
46%6%12%17%14%4
1980
21st to endDay
48%6%11%20%13%2
2178
April1st to 10thDay
37%7%12%22%18%4
1980
11th to 20thDay
41%5%9%20%19%6%
2149
21st to endDay
41%5%13%24%14%2
2340
May1st to 10thDay
42%8%14%21%12%2
2340
11th to 20thDay
51%10%12%17%9%1
2305
21st to endDay
45%9%14%23%8%1
2531
June1st to 10thDay
48%9%17%17%8%1
2340
11th to 20thDay
46%9%16%15%11%1
2340
21st to endDay
46%9%16%18%10%2
2340
July1st to 10thDay
52%12%14%14%8%1
2275
11th to 20thDay
51%13%17%10%9%1
2271
21st to endDay
50%12%16%14%7%1
2405
August1st to 10thDay
54%12%14%15%4
2314
11th to 20thDay
53%12%14%14%6%1
2303
21st to endDay
51%10%15%16%5%3
2410
September1st to 10thDay
49%8%11%17%12%3
1980
11th to 20thDay
49%7%10%18%14%2
1980
21st to endDay
46%7%10%18%14%5%
1980
October1st to 10thDay
40%5%10%17%23%5%
1932
11th to 20thDay
34%49%25%20%8%
1800
21st to endDay
35%38%23%22%8%
1980
November1st to 10thDay
31%49%21%27%8%
1786
11th to 20thDay
34%48%22%26%8%
1710
21st to endDay
37%46%24%22%6%
1710
December1st to 10thDay
49%5%7%19%15%5%
1710
11th to 20thDay
35%312%20%23%7%
2150
21st to endDay
42%48%24%19%3
3124
January1st to 10thNight
40%5%12%20%18%5%
2459
11th to 20thNight
45%410%17%19%5%
2365
21st to endNight
39%49%23%22%4
2574
February1st to 10thNight
39%5%13%21%18%3
2286
11th to 20thNight
44%49%22%16%5%
2099
21st to endNight
44%6%11%19%14%6%
1776
March1st to 10thNight
38%5%11%17%22%7%
2012
11th to 20thNight
45%6%12%21%13%3
1980
21st to endNight
44%6%13%22%13%2
2178
April1st to 10thNight
36%5%13%24%18%4
1980
11th to 20thNight
37%5%11%22%20%5%
1773
21st to endNight
37%6%14%27%14%2
1620
May1st to 10thNight
40%8%16%24%11%2
1620
11th to 20thNight
45%9%15%21%9%1
1593
21st to endNight
41%9%19%24%7%1
1745
June1st to 10thNight
41%11%19%20%8%1
1620
11th to 20thNight
36%9%24%21%9%1
1620
21st to endNight
35%11%20%20%12%2
1620
July1st to 10thNight
42%11%19%18%9%1
1575
11th to 20thNight
39%15%22%15%8%2
1566
21st to endNight
37%16%21%19%7%
1672
August1st to 10thNight
41%13%21%17%7%
1600
11th to 20thNight
43%12%18%16%10%1
1598
21st to endNight
45%9%19%19%7%1
1922
September1st to 10thNight
43%10%12%20%12%3
1980
11th to 20thNight
46%8%11%18%15%1
1980
21st to endNight
42%6%9%22%18%3
1980
October1st to 10thNight
40%7%10%18%22%3
2026
11th to 20thNight
37%5%10%24%18%6%
2160
21st to endNight
32%47%24%26%8%
2376
November1st to 10thNight
34%5%9%22%21%9%
2289
11th to 20thNight
34%48%20%25%9%
2470
21st to endNight
36%5%7%25%22%6%
2470
December1st to 10thNight
46%5%9%19%15%4
2470
11th to 20thNight
40%410%19%22%6%
3044
21st to endNight
43%6%11%20%18%2
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
36%26%30%7%1
270
11th to 20thDay
33%23%32%11%2
245
21st to endDay
31%34%28%6%2
264
February1st to 10thDay
34%26%31%8%2
240
11th to 20thDay
49%21%26%3
240
21st to endDay
40%29%23%7%1
198
March1st to 10thDay
27%25%28%16%3
387
11th to 20thDay
28%25%28%15%31
420
21st to endDay
29%25%27%14%6%
462
April1st to 10thDay
26%19%24%22%7%1
420
11th to 20thDay
23%21%25%20%9%2
412
21st to endDay
24%16%27%17%12%4
420
May1st to 10thDay
21%22%29%15%8%6%
423
11th to 20thDay
23%13%24%19%14%7%
447
21st to endDay
19%9%23%22%16%12%
485
June1st to 10thDay
15%10%24%27%15%9%
450
11th to 20thDay
13%7%21%27%20%11%
450
21st to endDay
11%10%30%24%13%11%
450
July1st to 10thDay
12%417%28%26%13%
445
11th to 20thDay
12%315%31%23%16%
444
21st to endDay
11%413%32%26%14%
488
August1st to 10thDay
19%6%20%23%17%16%
446
11th to 20thDay
13%6%14%30%24%14%
439
21st to endDay
14%417%29%20%16%
495
September1st to 10thDay
14%318%30%22%12%
450
11th to 20thDay
21%6%15%24%25%9%
450
21st to endDay
24%8%18%27%18%5%
450
October1st to 10thDay
24%10%19%23%16%8%
450
11th to 20thDay
16%14%30%24%12%3
450
21st to endDay
22%13%28%25%9%3
495
November1st to 10thDay
21%13%33%21%10%3
384
11th to 20thDay
23%19%37%16%41
270
21st to endDay
21%23%32%17%6%1
270
December1st to 10thDay
29%26%32%11%1
270
11th to 20thDay
23%19%39%16%21
270
21st to endDay
28%19%36%13%41
297
January1st to 10thNight
27%19%28%21%5%
760
11th to 20thNight
24%19%30%23%5%
728
21st to endNight
21%22%31%22%4
792
February1st to 10thNight
21%19%30%26%4
720
11th to 20thNight
26%25%28%19%2
703
21st to endNight
24%24%32%18%3
592
March1st to 10thNight
21%23%29%24%4
720
11th to 20thNight
24%18%30%19%8%1
720
21st to endNight
22%19%31%21%8%
792
April1st to 10thNight
21%20%26%25%8%1
720
11th to 20thNight
21%19%22%24%12%2
641
21st to endNight
16%13%23%33%14%1
540
May1st to 10thNight
16%14%28%25%15%2
540
11th to 20thNight
18%9%19%29%22%3
531
21st to endNight
16%6%14%27%31%7%
584
June1st to 10thNight
14%416%32%28%7%
540
11th to 20thNight
9%416%30%31%11%
540
21st to endNight
7%416%32%34%7%
540
July1st to 10thNight
14%27%30%40%7%
525
11th to 20thNight
11%310%25%41%10%
522
21st to endNight
7%38%31%39%11%
591
August1st to 10thNight
14%39%28%39%7%
537
11th to 20thNight
14%49%26%39%8%
534
21st to endNight
14%48%26%39%9%
653
September1st to 10thNight
16%311%24%37%8%
720
11th to 20thNight
21%7%9%24%33%7%
720
21st to endNight
22%7%13%29%26%3
720
October1st to 10thNight
21%11%15%21%23%8%
720
11th to 20thNight
21%13%22%27%15%3
720
21st to endNight
19%13%20%32%12%3
792
November1st to 10thNight
20%12%21%28%16%3
740
11th to 20thNight
22%14%20%32%10%2
760
21st to endNight
20%15%22%30%11%2
760
December1st to 10thNight
25%16%26%27%6%
760
11th to 20thNight
21%14%28%29%7%1
760
21st to endNight
27%15%25%28%5%
836
Page generated at 2024-01-09 16:24:28. Version ac07

Copyright 2024 Attilla Danko


Mount Mitchell Clear Sky Chart |Charts Home