Fort Hays State University
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Fort Hays State University clear sky chart from 2005-11-05 to 2017-09-23.

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
45%
15915
27%
46659
15%
15869
55%
15869
39%
25791

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
38%
900
29%
2327
13%
895
49%
895
41%
1362
January16th to endNight
40%
960
32%
2496
13%
960
52%
960
43%
1416
February1st to 15thNight
35%
764
22%
2175
8%
760
45%
760
31%
1344
February16th to endNight
34%
632
29%
1894
11%
632
47%
632
34%
1062
March1st to 15thNight
39%
647
27%
2087
15%
647
51%
647
35%
1106
March16th to endNight
31%
576
21%
2112
12%
576
44%
576
26%
1178
April1st to 15thNight
30%
539
22%
1840
12%
539
45%
539
29%
1024
April16th to endNight
34%
540
23%
1645
15%
540
47%
540
29%
988
May1st to 15thNight
37%
540
20%
1620
14%
540
47%
540
30%
990
May16th to endNight
39%
562
18%
1684
11%
561
47%
561
34%
961
June1st to 15thNight
42%
540
19%
1599
8%
540
51%
540
41%
862
June16th to endNight
55%
540
25%
1440
13%
540
62%
540
54%
751
July1st to 15thNight
63%
510
20%
1389
14%
510
66%
510
47%
767
July16th to endNight
69%
564
24%
1594
23%
531
72%
531
44%
850
August1st to 15thNight
67%
539
21%
1610
21%
536
71%
536
41%
894
August16th to endNight
66%
573
27%
1839
27%
573
72%
573
43%
934
September1st to 15thNight
53%
540
25%
1928
20%
540
65%
540
38%
983
September16th to endNight
54%
516
33%
1903
28%
516
65%
516
41%
885
October1st to 15thNight
45%
522
33%
1842
24%
522
56%
522
34%
952
October16th to endNight
47%
776
32%
2184
15%
776
56%
776
48%
1127
November1st to 15thNight
48%
875
35%
2275
14%
875
60%
875
53%
1179
November16th to endNight
44%
900
32%
2340
15%
900
54%
900
47%
1296
December1st to 15thNight
38%
900
25%
2340
11%
900
47%
900
40%
1359
December16th to endNight
40%
960
30%
2496
14%
960
51%
960
37%
1521

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
8%42432345%7%53%
48246
Night
7%424323447%55%
46847
Cloud CoverDay
8%42432445%7%53%
48244
Night
7%424323447%55%
46847
TransparencyDay
29%413%28%19%4
47937
Night
28%313%26%22%6%
46660
SeeingDay
10%6%29%33%17%2
5899
Night
9%7%33%37%11%
15919

By Month

Percentage Cloud Cover SW (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
5%42432335%8%57%
1611
16th to endDay
5%5%35%423446%54%
1728
February1st to 15thDay
6%6%35%5%34345%49%
1696
16th to endDay
5%5%2432445%5%55%
1580
March1st to 15thDay
8%5%243135%47%53%
1872
16th to endDay
12%7%34323445%47%
2112
April1st to 15thDay
11%5%24424347%49%
2106
16th to endDay
15%6%3432345%6%43%
2313
May1st to 15thDay
10%423324447%50%
2331
16th to endDay
11%42432435%8%48%
2430
June1st to 15thDay
6%313314448%56%
2358
16th to endDay
321232445%8%60%
2520
July1st to 15thDay
5%3234245%6%9%52%
2484
16th to endDay
6%31342446%8%54%
2466
August1st to 15thDay
7%5%244245%6%9%47%
2340
16th to endDay
6%4133245%5%7%56%
2361
September1st to 15thDay
10%5%2431335%5%53%
2031
16th to endDay
6%313313447%60%
1893
October1st to 15thDay
15%412112336%57%
1777
16th to endDay
7%413212235%64%
1686
November1st to 15thDay
5%212313346%63%
1583
16th to endDay
7%5%1221223464%
1620
December1st to 15thDay
7%7%25%42335%5%50%
1620
16th to endDay
7%6%36%434447%48%
1728
January1st to 15thNight
45%35%422335%57%
2327
16th to endNight
6%414323346%60%
2496
February1st to 15thNight
6%6%36%5%33446%49%
2165
16th to endNight
6%5%25%42445%5%55%
1894
March1st to 15thNight
6%5%2432335%8%54%
2087
16th to endNight
12%5%24324346%51%
2112
April1st to 15thNight
12%6%13323349%49%
1840
16th to endNight
13%42442345%7%47%
1645
May1st to 15thNight
10%4345%2446%7%47%
1619
16th to endNight
10%31342346%11%47%
1683
June1st to 15thNight
5%3133335%6%11%52%
1599
16th to endNight
31222437%11%59%
1440
July1st to 15thNight
41135%346%7%10%51%
1471
16th to endNight
5%3143245%6%11%51%
1702
August1st to 15thNight
5%2145%345%7%10%50%
1620
16th to endNight
4313423348%59%
1839
September1st to 15thNight
8%314312447%56%
1928
16th to endNight
5%212323346%62%
1903
October1st to 15thNight
11%423312335%59%
1842
16th to endNight
8%312212235%65%
2184
November1st to 15thNight
6%211313335%67%
2275
16th to endNight
6%413313345%62%
2340
December1st to 15thNight
8%423323338%55%
2340
16th to endNight
8%6%35%423346%51%
2496

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
5%5%1432335%7%57%
1611
16th to endDay
5%5%24424446%54%
1728
February1st to 15thDay
6%6%35%5%34345%49%
1696
16th to endDay
5%5%243245%45%55%
1580
March1st to 15thDay
7%5%2332345%6%53%
1872
16th to endDay
13%7%34423446%47%
2110
April1st to 15thDay
11%5%25%424346%49%
2106
16th to endDay
15%6%25%4235%47%42%
2313
May1st to 15thDay
10%42332445%7%49%
2331
16th to endDay
10%425%424448%47%
2430
June1st to 15thDay
6%31432445%8%56%
2358
16th to endDay
321331445%8%60%
2520
July1st to 15thDay
5%323335%5%6%10%51%
2484
16th to endDay
5%2134245%6%9%54%
2466
August1st to 15thDay
7%5%25%325%5%6%9%46%
2340
16th to endDay
6%4133235%6%7%56%
2361
September1st to 15thDay
10%5%2432335%6%52%
2031
16th to endDay
5%323224446%60%
1893
October1st to 15thDay
14%5%12112336%57%
1777
16th to endDay
7%413212235%63%
1686
November1st to 15thDay
5%212313346%63%
1583
16th to endDay
7%5%1221223464%
1620
December1st to 15thDay
7%8%3442336%5%50%
1620
16th to endDay
7%6%26%5%33346%48%
1728
January1st to 15thNight
45%35%423336%57%
2327
16th to endNight
5%414323336%59%
2496
February1st to 15thNight
6%6%46%5%34346%48%
2165
16th to endNight
5%5%25%424446%54%
1894
March1st to 15thNight
6%5%2432335%7%54%
2087
16th to endNight
12%5%24324346%50%
2112
April1st to 15thNight
11%6%13323348%49%
1840
16th to endNight
12%5%2442345%6%47%
1645
May1st to 15thNight
10%5%345%2345%6%47%
1619
16th to endNight
10%3134235%5%11%47%
1683
June1st to 15thNight
5%3133235%6%11%52%
1599
16th to endNight
311222437%11%59%
1440
July1st to 15thNight
4113425%6%7%9%51%
1471
16th to endNight
5%2133345%6%11%51%
1702
August1st to 15thNight
5%2145%245%7%10%50%
1620
16th to endNight
431342335%8%59%
1839
September1st to 15thNight
8%324213447%56%
1928
16th to endNight
5%212323446%62%
1903
October1st to 15thNight
10%413412326%58%
1842
16th to endNight
7%413113235%65%
2184
November1st to 15thNight
5%211212336%67%
2275
16th to endNight
6%413323345%62%
2340
December1st to 15thNight
8%414323348%55%
2340
16th to endNight
8%6%35%423347%50%
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
26%315%33%18%3
1612
16th to endDay
30%315%32%14%4
1728
February1st to 15thDay
36%418%24%10%4
1697
16th to endDay
28%314%25%20%6%
1580
March1st to 15thDay
29%312%28%20%6%
1872
16th to endDay
38%412%24%16%3
2112
April1st to 15thDay
36%411%27%17%4
2106
16th to endDay
40%411%28%13%1
2313
May1st to 15thDay
32%413%28%18%2
2331
16th to endDay
33%7%14%27%13%2
2434
June1st to 15thDay
25%417%29%16%6%
2358
16th to endDay
20%411%32%22%8%
2520
July1st to 15thDay
26%412%28%22%5%
2338
16th to endDay
24%5%13%30%21%4
2311
August1st to 15thDay
31%5%18%26%12%5%
2326
16th to endDay
25%5%11%27%23%5%
2361
September1st to 15thDay
32%310%25%19%8%
2031
16th to endDay
23%311%32%24%3
1893
October1st to 15thDay
29%210%28%23%5%
1777
16th to endDay
24%29%30%27%6%
1686
November1st to 15thDay
22%29%28%29%7%
1583
16th to endDay
24%19%31%27%5%
1620
December1st to 15thDay
34%315%28%15%1
1620
16th to endDay
36%312%27%17%2
1728
January1st to 15thNight
29%211%29%23%3
2327
16th to endNight
26%311%30%22%4
2496
February1st to 15thNight
37%413%25%14%4
2175
16th to endNight
29%312%26%19%8%
1894
March1st to 15thNight
28%310%25%23%8%
2087
16th to endNight
35%313%24%17%5%
2112
April1st to 15thNight
33%312%25%21%2
1840
16th to endNight
35%414%24%18%2
1645
May1st to 15thNight
36%413%21%19%4
1620
16th to endNight
30%6%20%26%13%2
1685
June1st to 15thNight
23%6%18%26%20%4
1599
16th to endNight
18%416%27%28%5%
1440
July1st to 15thNight
22%5%15%27%22%6%
1389
16th to endNight
25%414%29%20%5%
1594
August1st to 15thNight
26%5%18%29%14%5%
1610
16th to endNight
23%413%27%23%6%
1839
September1st to 15thNight
27%311%26%20%9%
1928
16th to endNight
22%39%25%32%6%
1903
October1st to 15thNight
29%39%23%26%8%
1842
16th to endNight
22%28%27%29%9%
2184
November1st to 15thNight
19%28%26%31%12%
2275
16th to endNight
25%19%27%24%10%
2340
December1st to 15thNight
29%215%30%19%2
2340
16th to endNight
34%214%25%20%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
10%8%40%32%8%
90
16th to endDay
9%10%41%25%13%
96
February1st to 15thDay
11%8%45%30%31
90
16th to endDay
122%40%18%16%1
81
March1st to 15thDay
7%15%43%27%41
90
16th to endDay
13%11%42%23%8%
96
April1st to 15thDay
12%18%35%24%8%
225
16th to endDay
22%10%35%22%6%
423
May1st to 15thDay
10%11%33%29%12%1
468
16th to endDay
16%8%31%29%10%2
517
June1st to 15thDay
6%5%29%38%15%4
495
16th to endDay
4427%39%21%2
495
July1st to 15thDay
6%222%38%25%4
475
16th to endDay
7%15%42%28%5%
515
August1st to 15thDay
9%115%44%26%3
493
16th to endDay
7%223%37%24%3
401
September1st to 15thDay
8%229%38%19%2
186
16th to endDay
9%5%23%30%25%5%
111
October1st to 15thDay
12%330%30%20%4
90
16th to endDay
8%5%31%34%16%4
96
November1st to 15thDay
5%341%32%16%1
90
16th to endDay
18%12%35%21%12%
90
December1st to 15thDay
11%16%48%12%11%
90
16th to endDay
18%9%46%19%5%
96
January1st to 15thNight
7%9%37%36%8%
900
16th to endNight
9%9%37%37%6%
960
February1st to 15thNight
10%6%40%35%7%
767
16th to endNight
9%11%40%31%6%
632
March1st to 15thNight
9%11%35%35%6%
647
16th to endNight
16%10%36%29%5%
576
April1st to 15thNight
16%11%39%28%4
539
16th to endNight
16%13%34%30%6%
540
May1st to 15thNight
12%8%36%33%8%
540
16th to endNight
12%8%35%30%13%
563
June1st to 15thNight
7%6%40%32%11%
540
16th to endNight
3334%45%12%
540
July1st to 15thNight
4123%50%19%
510
16th to endNight
7%17%48%23%1
564
August1st to 15thNight
7%17%51%21%
539
16th to endNight
4219%48%23%1
573
September1st to 15thNight
9%229%40%16%1
540
16th to endNight
7%331%39%16%1
516
October1st to 15thNight
13%7%29%33%14%1
522
16th to endNight
10%5%33%35%14%1
776
November1st to 15thNight
8%8%32%37%12%
875
16th to endNight
10%7%35%34%10%1
900
December1st to 15thNight
11%9%36%36%6%
900
16th to endNight
11%9%32%37%8%
960
Page generated at 2017-09-24 08:15:58. Version ac04

Copyright 2017 A. Danko


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