Smoky Mountain Stargaze
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Smoky Mountain Stargaze clear sky chart from 2005-11-05 to 2017-09-18.

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
49%
15557
19%
46938
14%
15515
55%
15515
24%
30599

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
31%
719
20%
2327
11%
716
43%
716
20%
1534
January16th to endNight
27%
768
21%
2496
10%
768
40%
768
19%
1651
February1st to 15thNight
33%
703
22%
2139
12%
700
45%
700
23%
1393
February16th to endNight
25%
631
20%
1893
11%
631
34%
631
18%
1314
March1st to 15thNight
35%
720
20%
2037
13%
720
42%
720
21%
1394
March16th to endNight
38%
768
15%
2112
10%
768
42%
768
23%
1440
April1st to 15thNight
41%
674
20%
1932
12%
674
48%
674
27%
1211
April16th to endNight
50%
540
21%
1647
13%
540
58%
540
27%
1042
May1st to 15thNight
51%
540
14%
1620
9%
540
55%
540
24%
1081
May16th to endNight
63%
561
15%
1683
13%
561
65%
561
26%
1099
June1st to 15thNight
70%
540
12%
1620
10%
540
71%
540
27%
1046
June16th to endNight
75%
540
15%
1620
13%
540
76%
540
31%
1017
July1st to 15thNight
68%
510
10%
1530
8%
510
69%
510
24%
1057
July16th to endNight
73%
564
12%
1595
11%
531
73%
531
27%
1053
August1st to 15thNight
68%
539
14%
1609
13%
536
68%
536
23%
1105
August16th to endNight
68%
579
17%
1854
17%
579
69%
579
23%
1205
September1st to 15thNight
62%
720
15%
1980
14%
720
62%
720
23%
1384
September16th to endNight
60%
669
21%
1848
18%
669
61%
669
28%
1207
October1st to 15thNight
55%
660
31%
1862
26%
660
60%
660
32%
1127
October16th to endNight
53%
704
30%
2112
25%
704
62%
704
33%
1228
November1st to 15thNight
55%
700
27%
2246
26%
700
62%
700
33%
1271
November16th to endNight
45%
720
25%
2340
19%
720
54%
720
26%
1434
December1st to 15thNight
41%
720
20%
2340
15%
720
48%
720
20%
1547
December16th to endNight
35%
768
18%
2496
14%
768
42%
768
16%
1759

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%7%36%6%35%5%5%7%35%
47849
Night
12%6%35%5%35%45%7%40%
47136
TransparencyDay
47%5%10%18%14%3
47550
Night
41%5%12%20%15%3
46939
SeeingDay
18%7%16%22%19%14%
5419
Night
18%6%16%30%22%4
15561

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
17%7%36%434336%37%
1611
16th to endDay
14%7%25%32445%6%43%
1728
February1st to 15thDay
14%9%25%5%24446%38%
1720
16th to endDay
16%6%36%424347%39%
1580
March1st to 15thDay
18%7%34435%346%39%
1921
16th to endDay
16%8%45%425%45%5%36%
2111
April1st to 15thDay
13%5%15%5%25%46%7%41%
2025
16th to endDay
16%6%35%42445%6%39%
2311
May1st to 15thDay
15%7%36%6%445%5%6%35%
2331
16th to endDay
13%6%27%6%36%6%5%7%32%
2431
June1st to 15thDay
10%6%46%7%5%7%7%6%7%29%
2340
16th to endDay
7%5%36%7%5%7%6%7%10%32%
2340
July1st to 15thDay
11%7%38%9%5%8%7%6%8%21%
2340
16th to endDay
10%6%36%7%5%8%8%7%10%24%
2465
August1st to 15thDay
9%7%37%9%48%8%6%9%24%
2340
16th to endDay
14%7%37%9%46%5%6%8%24%
2333
September1st to 15thDay
13%8%46%7%46%6%5%6%29%
1980
16th to endDay
16%6%36%5%345%5%8%34%
1837
October1st to 15thDay
13%414324336%51%
1767
16th to endDay
12%6%13313325%55%
1760
November1st to 15thDay
10%5%2341335%5%53%
1610
16th to endDay
15%5%25%423346%45%
1620
December1st to 15thDay
17%9%344245%5%5%36%
1620
16th to endDay
21%9%35%42324438%
1728
January1st to 15thNight
16%8%346%35%446%37%
2327
16th to endNight
14%8%46%5%34445%38%
2496
February1st to 15thNight
12%7%45%5%14446%42%
2130
16th to endNight
15%8%37%5%34445%36%
1893
March1st to 15thNight
14%7%35%5%35%446%38%
2037
16th to endNight
13%7%26%5%35%447%39%
2112
April1st to 15thNight
11%6%145%34347%46%
1932
16th to endNight
11%5%245%24447%46%
1647
May1st to 15thNight
11%5%36%5%35%46%8%38%
1619
16th to endNight
7%425%7%36%7%7%9%38%
1682
June1st to 15thNight
6%5%245%46%7%7%12%37%
1620
16th to endNight
6%424435%6%7%11%43%
1620
July1st to 15thNight
7%6%25%5%46%6%8%11%33%
1620
16th to endNight
7%5%15%5%36%7%9%11%35%
1703
August1st to 15thNight
9%7%25%6%36%5%7%9%37%
1620
16th to endNight
9%5%26%6%5%45%8%9%36%
1854
September1st to 15thNight
10%6%27%6%45%6%6%8%35%
1980
16th to endNight
12%6%2442446%8%41%
1848
October1st to 15thNight
12%5%1431335%7%51%
1862
16th to endNight
9%6%2442443454%
2112
November1st to 15thNight
11%5%24314336%53%
2246
16th to endNight
14%7%25%32434447%
2340
December1st to 15thNight
14%8%36%5%3445%6%37%
2340
16th to endNight
18%9%46%5%24446%33%
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
49%36%17%17%5%
1612
16th to endDay
41%28%23%18%5%
1728
February1st to 15thDay
47%36%19%19%2
1722
16th to endDay
46%211%17%19%3
1580
March1st to 15thDay
46%28%20%16%5%
1921
16th to endDay
48%5%12%17%12%2
2112
April1st to 15thDay
41%412%23%16%3
2025
16th to endDay
45%38%21%16%3
2311
May1st to 15thDay
49%5%11%19%11%2
2331
16th to endDay
49%8%11%19%9%1
2435
June1st to 15thDay
52%7%16%17%5%
2340
16th to endDay
45%7%14%17%11%2
2340
July1st to 15thDay
56%9%14%13%5%
2201
16th to endDay
49%9%17%14%6%1
2310
August1st to 15thDay
53%8%13%15%6%1
2327
16th to endDay
57%5%13%15%6%1
2333
September1st to 15thDay
55%6%8%14%12%2
1980
16th to endDay
47%5%10%15%18%2
1837
October1st to 15thDay
35%38%21%24%6%
1767
16th to endDay
33%36%21%25%9%
1760
November1st to 15thDay
33%25%19%28%10%
1610
16th to endDay
40%26%18%24%7%
1620
December1st to 15thDay
48%38%16%17%6%
1620
16th to endDay
50%29%16%16%5%
1728
January1st to 15thNight
47%28%18%17%5%
2327
16th to endNight
49%26%18%19%4
2496
February1st to 15thNight
43%38%20%19%3
2139
16th to endNight
50%38%20%15%2
1893
March1st to 15thNight
46%410%17%16%4
2037
16th to endNight
45%5%13%22%12%1
2112
April1st to 15thNight
38%312%25%16%3
1932
16th to endNight
39%5%11%23%17%2
1647
May1st to 15thNight
44%5%16%22%10%1
1620
16th to endNight
38%9%18%23%9%1
1684
June1st to 15thNight
36%10%26%20%5%
1620
16th to endNight
30%12%20%22%11%1
1620
July1st to 15thNight
40%12%21%18%6%
1530
16th to endNight
35%11%25%18%7%1
1595
August1st to 15thNight
41%10%18%18%10%
1609
16th to endNight
41%8%20%21%6%1
1854
September1st to 15thNight
43%9%15%18%10%2
1980
16th to endNight
39%7%12%19%18%1
1848
October1st to 15thNight
33%5%9%23%24%3
1862
16th to endNight
33%36%23%25%7%
2112
November1st to 15thNight
34%27%20%25%9%
2246
16th to endNight
41%25%22%20%6%
2340
December1st to 15thNight
46%48%16%17%7%
2340
16th to endNight
53%37%15%15%3
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
37%10%28%18%31
90
16th to endDay
26%28%35%7%3
96
February1st to 15thDay
30%24%35%7%2
90
16th to endDay
39%16%29%11%3
81
March1st to 15thDay
28%13%21%24%9%1
211
16th to endDay
21%13%22%26%12%3
288
April1st to 15thDay
20%10%16%32%15%4
270
16th to endDay
17%7%20%24%21%8%
270
May1st to 15thDay
19%13%22%15%17%11%
288
16th to endDay
19%7%15%23%16%18%
331
June1st to 15thDay
13%411%24%26%19%
315
16th to endDay
12%317%20%17%27%
315
July1st to 15thDay
13%115%22%21%24%
305
16th to endDay
10%25%21%28%31%
326
August1st to 15thDay
15%110%23%22%26%
313
16th to endDay
15%18%19%27%27%
332
September1st to 15thDay
15%6%8%17%32%19%
315
16th to endDay
19%211%25%27%14%
262
October1st to 15thDay
18%7%14%24%23%10%
255
16th to endDay
16%8%16%30%21%6%
272
November1st to 15thDay
20%5%19%31%19%4
118
16th to endDay
23%8%26%25%14%1
90
December1st to 15thDay
22%16%36%17%42
90
16th to endDay
44%8%31%10%5%
96
January1st to 15thNight
28%10%25%27%7%
720
16th to endNight
23%11%30%30%4
768
February1st to 15thNight
23%10%27%34%3
704
16th to endNight
27%15%28%25%3
631
March1st to 15thNight
23%11%24%31%7%
720
16th to endNight
19%10%24%31%12%1
768
April1st to 15thNight
19%11%22%30%13%1
674
16th to endNight
15%7%17%37%19%2
540
May1st to 15thNight
15%6%17%36%21%3
540
16th to endNight
12%28%33%34%9%
563
June1st to 15thNight
10%7%33%38%9%
540
16th to endNight
8%15%27%46%11%
540
July1st to 15thNight
11%15%23%49%9%
510
16th to endNight
9%221%50%16%
564
August1st to 15thNight
10%1225%47%12%
539
16th to endNight
12%321%48%13%
579
September1st to 15thNight
14%25%26%40%10%
720
16th to endNight
17%28%31%34%5%
669
October1st to 15thNight
15%7%14%28%25%8%
660
16th to endNight
15%8%16%35%19%4
704
November1st to 15thNight
15%6%17%34%21%5%
700
16th to endNight
21%8%19%33%15%1
720
December1st to 15thNight
22%9%19%35%11%1
720
16th to endNight
26%8%25%31%8%
768
Page generated at 2017-09-19 07:32:26. Version ac04

Copyright 2017 A. Danko


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