Mckinney Falls State Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Mckinney Falls State Park clear sky chart from 2005-11-05 to 2017-09-21.

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
53%
15433
26%
46989
19%
15388
60%
15388
34%
27095

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
41%
897
26%
2327
13%
895
48%
895
34%
1463
January16th to endNight
39%
910
30%
2446
14%
910
48%
910
34%
1516
February1st to 15thNight
37%
704
28%
2106
14%
698
48%
698
31%
1242
February16th to endNight
27%
632
28%
1894
9%
632
42%
632
30%
1117
March1st to 15thNight
34%
540
27%
1980
15%
540
48%
540
25%
1154
March16th to endNight
34%
576
23%
2112
17%
576
45%
576
26%
1205
April1st to 15thNight
32%
539
23%
1977
13%
539
47%
539
26%
1129
April16th to endNight
33%
540
25%
1775
16%
540
47%
540
27%
1078
May1st to 15thNight
37%
539
22%
1619
16%
539
46%
539
29%
1010
May16th to endNight
52%
562
26%
1684
22%
561
61%
561
37%
965
June1st to 15thNight
74%
540
23%
1620
24%
540
78%
540
53%
793
June16th to endNight
71%
540
21%
1620
23%
540
75%
540
38%
930
July1st to 15thNight
79%
510
21%
1530
24%
510
82%
510
46%
814
July16th to endNight
83%
564
25%
1594
28%
531
85%
531
44%
844
August1st to 15thNight
88%
539
28%
1631
32%
536
88%
536
55%
771
August16th to endNight
78%
573
20%
1991
25%
573
79%
573
31%
1121
September1st to 15thNight
78%
540
21%
1980
25%
540
79%
540
34%
1071
September16th to endNight
73%
510
26%
1881
28%
510
75%
510
30%
1053
October1st to 15thNight
72%
520
34%
1840
34%
520
75%
520
40%
923
October16th to endNight
62%
704
35%
2112
24%
704
68%
704
48%
1073
November1st to 15thNight
54%
700
28%
2100
19%
700
59%
700
36%
1216
November16th to endNight
48%
894
30%
2334
16%
894
55%
894
39%
1407
December1st to 15thNight
43%
900
27%
2340
15%
900
47%
900
30%
1540
December16th to endNight
40%
960
23%
2496
11%
960
46%
960
29%
1660

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%2443445%7%45%
47864
Night
11%423323347%52%
47192
TransparencyDay
37%5%9%19%18%8%
47564
Night
31%411%21%18%11%
46997
SeeingDay
11%315%28%29%10%
5401
Night
13%423%36%19%1
15438

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
18%423323336%48%
1611
16th to endDay
16%5%14313335%51%
1788
February1st to 15thDay
16%6%14313235%51%
1750
16th to endDay
18%6%15%31333448%
1580
March1st to 15thDay
21%6%24412345%44%
1980
16th to endDay
16%6%25%313345%47%
2110
April1st to 15thDay
14%7%25%434446%42%
1971
16th to endDay
13%6%35%433446%42%
2182
May1st to 15thDay
15%8%35%5%35%45%5%37%
2331
16th to endDay
13%7%36%6%35%5%6%8%34%
2430
June1st to 15thDay
5%415%5%35%5%6%10%44%
2340
16th to endDay
9%5%25%7%5%5%7%7%8%34%
2340
July1st to 15thDay
8%4245%46%6%6%11%38%
2340
16th to endDay
6%425%5%46%6%6%10%42%
2466
August1st to 15thDay
311232446%10%60%
2315
16th to endDay
7%425%5%47%5%6%10%40%
2211
September1st to 15thDay
8%427%6%36%5%6%7%41%
1980
16th to endDay
8%5%26%435%5%6%6%45%
1871
October1st to 15thDay
10%42442335%7%51%
1779
16th to endDay
8%21222324465%
1760
November1st to 15thDay
11%6%245%34445%46%
1758
16th to endDay
14%6%2332332453%
1623
December1st to 15thDay
18%7%23323335%44%
1620
16th to endDay
16%6%34324445%42%
1728
January1st to 15thNight
17%5%13213235%50%
2327
16th to endNight
17%413323345%50%
2446
February1st to 15thNight
15%6%2332223453%
2102
16th to endNight
14%5%23324345%51%
1894
March1st to 15thNight
16%6%23323436%48%
1980
16th to endNight
14%6%3331335%6%48%
2112
April1st to 15thNight
14%5%2431335%6%47%
1977
16th to endNight
16%5%23423346%45%
1775
May1st to 15thNight
12%5%25%434348%45%
1619
16th to endNight
9%3134245%6%11%47%
1683
June1st to 15thNight
32222345%9%63%
1620
16th to endNight
5%314425%5%6%9%52%
1620
July1st to 15thNight
5%21232337%11%55%
1620
16th to endNight
421333436%11%54%
1702
August1st to 15thNight
21132237%10%64%
1641
16th to endNight
6%3134346%7%10%46%
1991
September1st to 15thNight
7%314434449%51%
1980
16th to endNight
7%414425%5%47%50%
1881
October1st to 15thNight
8%212323247%59%
1840
16th to endNight
9%32212235%65%
2112
November1st to 15thNight
11%414423445%53%
2100
16th to endNight
14%5%22312235%56%
2334
December1st to 15thNight
15%6%2442333447%
2340
16th to endNight
18%6%2332433446%
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
38%35%18%20%12%
1612
16th to endDay
35%25%16%24%14%
1788
February1st to 15thDay
37%36%15%21%15%
1751
16th to endDay
40%35%18%19%12%
1580
March1st to 15thDay
43%47%11%21%12%
1980
16th to endDay
39%46%17%21%9%
2112
April1st to 15thDay
42%47%15%17%12%
1971
16th to endDay
42%5%5%19%16%10%
2182
May1st to 15thDay
46%5%7%14%17%7%
2331
16th to endDay
46%6%10%17%15%4
2434
June1st to 15thDay
31%7%11%22%20%4
2340
16th to endDay
42%8%11%20%14%2
2340
July1st to 15thDay
35%7%16%25%12%2
2201
16th to endDay
32%8%18%28%11%
2311
August1st to 15thDay
19%6%17%37%17%1
2301
16th to endDay
36%9%16%23%10%3
2211
September1st to 15thDay
40%6%11%20%14%6%
1980
16th to endDay
35%7%9%19%18%9%
1871
October1st to 15thDay
31%5%10%18%19%14%
1779
16th to endDay
22%36%17%30%20%
1760
November1st to 15thDay
38%48%20%17%10%
1758
16th to endDay
36%25%12%22%20%
1623
December1st to 15thDay
44%28%17%18%8%
1620
16th to endDay
43%48%15%18%10%
1728
January1st to 15thNight
36%25%17%19%16%
2327
16th to endNight
36%25%16%21%17%
2446
February1st to 15thNight
36%25%14%20%20%
2112
16th to endNight
35%45%18%19%16%
1894
March1st to 15thNight
38%49%13%21%13%
1980
16th to endNight
36%410%16%21%10%
2112
April1st to 15thNight
36%48%17%17%14%
1977
16th to endNight
39%410%18%15%11%
1775
May1st to 15thNight
37%5%10%20%16%8%
1620
16th to endNight
29%6%16%28%15%3
1685
June1st to 15thNight
17%5%16%28%27%4
1620
16th to endNight
27%7%17%28%16%2
1620
July1st to 15thNight
20%7%23%33%12%
1530
16th to endNight
21%7%26%35%8%
1594
August1st to 15thNight
15%5%24%36%16%1
1631
16th to endNight
29%9%22%26%9%3
1991
September1st to 15thNight
30%5%19%24%14%6%
1980
16th to endNight
31%7%14%20%17%9%
1881
October1st to 15thNight
24%5%10%24%19%14%
1840
16th to endNight
22%25%18%27%22%
2112
November1st to 15thNight
31%410%20%19%12%
2100
16th to endNight
32%36%14%20%22%
2334
December1st to 15thNight
40%47%19%18%9%
2340
16th to endNight
41%46%14%21%12%
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
18%6%27%35%8%2
90
16th to endDay
17%6%36%25%11%3
96
February1st to 15thDay
14%5%37%24%16%1
90
16th to endDay
20%8%35%28%6%
81
March1st to 15thDay
27%7%33%17%11%2
90
16th to endDay
13%428%38%11%4
96
April1st to 15thDay
8%11%33%30%14%2
90
16th to endDay
14%9%36%26%12%
292
May1st to 15thDay
16%5%34%30%12%
468
16th to endDay
16%6%22%32%19%2
517
June1st to 15thDay
7%19%40%33%8%
495
16th to endDay
9%26%33%34%13%
495
July1st to 15thDay
6%7%32%42%10%
475
16th to endDay
4323%48%18%
515
August1st to 15thDay
5%115%55%20%
468
16th to endDay
14%5%24%30%25%
251
September1st to 15thDay
2216%46%31%
135
16th to endDay
5%415%36%38%
105
October1st to 15thDay
427%52%15%
90
16th to endDay
17%18%23%31%17%
96
November1st to 15thDay
28%414%31%14%6%
90
16th to endDay
21%8%24%27%12%5%
90
December1st to 15thDay
22%224%21%18%11%
90
16th to endDay
17%12%36%25%6%2
96
January1st to 15thNight
20%7%25%33%12%
900
16th to endNight
19%7%30%34%8%
910
February1st to 15thNight
17%11%29%33%7%
704
16th to endNight
19%8%42%25%3
632
March1st to 15thNight
18%7%35%33%5%
540
16th to endNight
15%9%36%33%4
576
April1st to 15thNight
15%7%40%33%2
539
16th to endNight
16%7%37%29%7%
540
May1st to 15thNight
13%7%37%33%7%
540
16th to endNight
9%329%38%18%
563
June1st to 15thNight
3116%52%24%1
540
16th to endNight
5%14%46%28%3
540
July1st to 15thNight
5%8%46%36%2
510
16th to endNight
41345%40%4
564
August1st to 15thNight
3246%42%5%
539
16th to endNight
7%438%45%4
573
September1st to 15thNight
7%434%46%6%
540
16th to endNight
8%16%32%46%5%
510
October1st to 15thNight
9%110%42%30%4
520
16th to endNight
9%321%34%27%2
704
November1st to 15thNight
12%424%34%22%2
700
16th to endNight
17%424%34%16%2
894
December1st to 15thNight
21%6%25%35%10%1
900
16th to endNight
21%6%27%33%9%
960
Page generated at 2017-09-22 06:35:29. Version ac04

Copyright 2017 A. Danko


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