Lincoln
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lincoln clear sky chart from 2005-11-06 to 2024-03-23.

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
39%
24878
22%
80454
12%
24780
48%
24780
29%
48404

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
29%
940
17%
4069
7%
926
40%
926
16%
2798
January11th to 20thNight
29%
948
22%
4006
9%
930
38%
930
18%
2450
January21st to endNight
27%
1032
15%
4471
7%
1023
36%
1023
17%
2885
February1st to 10thNight
26%
950
15%
2470
5%
950
33%
950
24%
1728
February11th to 20thNight
29%
872
18%
2347
6%
868
38%
868
28%
1529
February21st to endNight
27%
628
25%
1884
6%
628
42%
628
30%
1118
March1st to 10thNight
29%
622
24%
2142
12%
622
43%
622
26%
1249
March11th to 20thNight
28%
570
21%
2090
13%
570
40%
570
23%
1256
March21st to endNight
25%
600
13%
2200
7%
600
34%
600
16%
1489
April1st to 10thNight
26%
540
19%
1954
12%
540
38%
540
25%
1135
April11th to 20thNight
27%
533
23%
1644
13%
533
42%
533
27%
990
April21st to endNight
32%
540
20%
1620
15%
540
43%
540
26%
1031
May1st to 10thNight
35%
540
15%
1620
10%
540
43%
540
25%
1048
May11th to 20thNight
37%
531
17%
1594
12%
531
45%
531
29%
990
May21st to endNight
41%
583
12%
1746
7%
582
46%
582
27%
1119
June1st to 10thNight
59%
540
22%
1490
12%
540
63%
540
42%
845
June11th to 20thNight
53%
540
21%
1440
8%
540
58%
540
42%
825
June21st to endNight
52%
540
22%
1536
10%
540
58%
540
46%
814
July1st to 10thNight
69%
525
17%
1575
12%
525
70%
525
39%
871
July11th to 20thNight
73%
522
21%
1566
17%
522
75%
522
47%
812
July21st to endNight
74%
591
25%
1673
23%
558
78%
558
47%
867
August1st to 10thNight
70%
537
21%
1601
23%
534
72%
534
40%
896
August11th to 20thNight
67%
534
28%
1600
28%
534
74%
534
43%
847
August21st to endNight
63%
594
29%
1804
29%
594
69%
594
42%
972
September1st to 10thNight
56%
540
24%
1908
23%
540
64%
540
39%
945
September11th to 20thNight
57%
540
30%
1980
28%
540
66%
540
38%
976
September21st to endNight
46%
540
30%
1980
23%
540
59%
540
37%
979
October1st to 10thNight
42%
634
26%
2074
18%
634
49%
634
30%
1201
October11th to 20thNight
34%
720
27%
2160
12%
720
46%
720
35%
1209
October21st to endNight
36%
792
26%
2376
13%
792
46%
792
32%
1366
November1st to 10thNight
41%
920
29%
2400
12%
920
53%
920
43%
1362
November11th to 20thNight
33%
950
29%
2470
9%
950
46%
950
37%
1503
November21st to endNight
34%
950
24%
2632
11%
950
43%
950
34%
1576
December1st to 10thNight
30%
950
20%
2660
7%
950
41%
950
31%
1642
December11th to 20thNight
32%
949
25%
3103
9%
948
43%
948
26%
1793
December21st to endNight
27%
1041
15%
4569
8%
1026
41%
1026
14%
3288

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
11%7%36%5%3445%7%44%
78806
Night
10%7%36%42445%7%48%
81108
TransparencyDay
39%7%13%25%15%2
78529
Night
36%6%13%26%17%3
80905
SeeingDay
14%9%31%29%14%3
14813
Night
13%9%34%33%10%1
24909

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
11%12%5%9%10%5%5%345%29%
2847
11th to 20thDay
9%11%5%8%5%38%445%37%
2850
21st to endDay
8%12%6%12%6%34446%35%
3135
February1st to 10thDay
10%10%5%7%6%345%6%6%36%
1710
11th to 20thDay
9%9%37%43446%7%43%
1735
21st to endDay
10%7%46%5%34447%47%
1570
March1st to 10thDay
10%8%47%434436%46%
2038
11th to 20thDay
15%9%46%423345%43%
2090
21st to endDay
17%12%46%6%4445%5%33%
2200
April1st to 10thDay
15%7%35%433346%45%
2005
11th to 20thDay
16%7%36%5%35%45%8%40%
2264
21st to endDay
19%7%35%43445%7%39%
2340
May1st to 10thDay
16%6%36%5%35%6%5%7%37%
2340
11th to 20thDay
15%6%25%6%35%45%8%42%
2302
21st to endDay
15%7%37%6%36%5%6%8%34%
2531
June1st to 10thDay
7%424435%5%6%9%51%
2466
11th to 20thDay
9%5%334346%6%9%48%
2520
21st to endDay
7%4246%45%5%6%8%48%
2414
July1st to 10thDay
9%4244345%6%10%49%
2340
11th to 20thDay
5%3245%2446%9%56%
2340
21st to endDay
6%425%5%35%6%8%10%48%
2546
August1st to 10thDay
7%5%25%5%46%7%7%10%41%
2328
11th to 20thDay
7%424435%5%7%8%51%
2301
21st to endDay
9%5%244245%6%7%54%
2552
September1st to 10thDay
14%42432345%5%53%
2048
11th to 20thDay
10%5%14433446%55%
1980
21st to endDay
10%42442435%6%57%
1980
October1st to 10thDay
14%7%24433435%52%
1868
11th to 20thDay
12%5%3442333457%
1800
21st to endDay
13%8%25%433346%49%
1980
November1st to 10thDay
9%6%24324447%56%
1673
11th to 20thDay
10%5%35%5%34446%51%
1710
21st to endDay
13%9%34424348%45%
1544
December1st to 10thDay
9%7%35%6%3446%7%47%
1520
11th to 20thDay
8%10%47%5%35%45%8%41%
1918
21st to endDay
15%11%5%13%6%44446%28%
3021
January1st to 10thNight
8%10%412%8%45%46%6%32%
4108
11th to 20thNight
9%9%36%5%39%5%5%5%41%
4120
21st to endNight
12%12%6%10%5%23346%39%
4532
February1st to 10thNight
11%10%46%5%35%45%6%40%
2470
11th to 20thNight
9%7%36%6%445%5%7%43%
2346
21st to endNight
10%8%35%5%24447%50%
1884
March1st to 10thNight
10%7%35%424445%51%
2142
11th to 20thNight
16%8%35%423345%47%
2090
21st to endNight
18%9%36%6%35%45%6%34%
2200
April1st to 10thNight
12%7%25%5%2445%7%47%
1954
11th to 20thNight
11%7%36%5%23448%47%
1644
21st to endNight
16%7%25%33445%7%45%
1620
May1st to 10thNight
15%6%35%4345%6%9%40%
1620
11th to 20thNight
12%7%25%6%2435%7%47%
1593
21st to endNight
13%7%35%5%245%5%9%43%
1745
June1st to 10thNight
5%2235%35%47%10%55%
1490
11th to 20thNight
6%4234245%7%9%53%
1440
21st to endNight
421432446%8%60%
1536
July1st to 10thNight
6%42443446%9%54%
1620
11th to 20thNight
32233345%6%10%60%
1620
21st to endNight
3223425%5%7%10%57%
1772
August1st to 10thNight
4424435%5%6%10%54%
1611
11th to 20thNight
5%325%42445%9%57%
1600
21st to endNight
7%5%1433345%6%60%
1804
September1st to 10thNight
8%42432335%7%59%
1908
11th to 20thNight
9%31342445%7%59%
1980
21st to endNight
9%324324445%60%
1980
October1st to 10thNight
13%6%24434447%51%
2074
11th to 20thNight
13%5%2431334458%
2160
21st to endNight
14%6%24322445%54%
2376
November1st to 10thNight
7%324424447%59%
2400
11th to 20thNight
9%5%35%42435%6%54%
2470
21st to endNight
11%7%34423346%54%
2632
December1st to 10thNight
8%6%36%5%3445%7%49%
2660
11th to 20thNight
9%8%36%42335%6%52%
3279
21st to endNight
18%13%5%10%5%2333434%
4628

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
56%6%13%17%8%1
2848
11th to 20thDay
47%6%17%18%11%1
2850
21st to endDay
50%6%12%18%12%
3135
February1st to 10thDay
47%6%16%20%10%1
1710
11th to 20thDay
41%5%13%23%15%3
1744
21st to endDay
38%6%13%24%16%3
1570
March1st to 10thDay
39%6%11%26%16%2
2038
11th to 20thDay
44%6%10%23%16%1
2090
21st to endDay
52%7%15%18%7%1
2200
April1st to 10thDay
40%5%13%25%16%2
2005
11th to 20thDay
43%5%12%24%13%2
2264
21st to endDay
45%7%10%25%13%
2340
May1st to 10thDay
46%8%12%19%14%1
2340
11th to 20thDay
41%8%14%24%13%
2306
21st to endDay
46%9%14%19%11%1
2531
June1st to 10thDay
29%7%17%32%13%2
2466
11th to 20thDay
31%8%14%29%16%2
2520
21st to endDay
31%9%14%28%14%4
2414
July1st to 10thDay
29%7%16%30%16%2
2276
11th to 20thDay
25%7%15%29%20%5%
2271
21st to endDay
28%8%17%30%16%1
2405
August1st to 10thDay
34%12%19%24%10%2
2314
11th to 20thDay
28%8%15%30%19%2
2301
21st to endDay
28%7%13%26%21%6%
2552
September1st to 10thDay
31%5%12%28%19%5%
2048
11th to 20thDay
30%6%12%29%21%2
1980
21st to endDay
28%49%32%25%1
1980
October1st to 10thDay
36%5%10%24%23%1
1868
11th to 20thDay
32%48%27%23%6%
1800
21st to endDay
37%5%13%21%20%4
1980
November1st to 10thDay
29%414%28%22%3
1673
11th to 20thDay
34%6%13%26%20%2
1710
21st to endDay
39%411%29%15%2
1544
December1st to 10thDay
36%5%16%27%14%2
1520
11th to 20thDay
41%6%16%29%9%
1915
21st to endDay
58%6%9%18%8%
3021
January1st to 10thNight
49%6%13%18%12%
4108
11th to 20thNight
42%5%15%25%12%1
4120
21st to endNight
48%414%20%14%1
4532
February1st to 10thNight
46%6%13%19%13%3
2470
11th to 20thNight
39%6%14%24%15%3
2347
21st to endNight
34%5%11%24%21%6%
1884
March1st to 10thNight
35%6%11%27%18%3
2142
11th to 20thNight
41%49%24%19%3
2090
21st to endNight
50%5%14%20%9%1
2200
April1st to 10thNight
36%5%11%26%18%3
1954
11th to 20thNight
36%5%13%27%17%3
1644
21st to endNight
40%6%11%24%18%1
1620
May1st to 10thNight
40%8%15%21%14%2
1620
11th to 20thNight
37%6%16%24%17%1
1594
21st to endNight
38%8%18%20%13%2
1746
June1st to 10thNight
24%8%16%32%18%2
1490
11th to 20thNight
25%7%16%28%18%5%
1440
21st to endNight
21%7%15%33%21%3
1536
July1st to 10thNight
26%7%13%31%19%5%
1575
11th to 20thNight
20%7%16%29%23%6%
1566
21st to endNight
18%9%17%35%19%2
1673
August1st to 10thNight
25%9%19%30%16%1
1601
11th to 20thNight
24%6%14%34%20%2
1600
21st to endNight
24%7%12%27%21%9%
1804
September1st to 10thNight
25%413%28%22%8%
1908
11th to 20thNight
25%5%11%33%22%4
1980
21st to endNight
26%5%8%28%29%3
1980
October1st to 10thNight
33%6%11%23%23%3
2074
11th to 20thNight
31%48%25%26%7%
2160
21st to endNight
33%412%23%25%3
2376
November1st to 10thNight
24%6%13%27%25%5%
2400
11th to 20thNight
32%411%30%20%3
2470
21st to endNight
34%412%26%21%3
2632
December1st to 10thNight
35%5%14%29%15%1
2660
11th to 20thNight
34%5%13%35%13%1
3281
21st to endNight
54%5%9%22%8%1
4628

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
17%16%38%20%7%1
270
11th to 20thDay
21%14%37%21%7%
270
21st to endDay
14%12%42%22%9%
297
February1st to 10thDay
15%19%43%19%3
270
11th to 20thDay
16%14%38%24%7%
270
21st to endDay
11%20%43%20%5%
225
March1st to 10thDay
17%13%42%23%41
270
11th to 20thDay
24%14%36%19%6%1
270
21st to endDay
29%17%35%15%3
270
April1st to 10thDay
19%20%38%19%3
265
11th to 20thDay
19%15%37%21%7%
542
21st to endDay
23%15%32%20%8%2
600
May1st to 10thDay
19%12%34%25%9%1
603
11th to 20thDay
19%8%35%24%12%2
625
21st to endDay
17%8%31%29%14%2
679
June1st to 10thDay
5%6%22%39%23%5%
630
11th to 20thDay
9%6%29%35%18%4
630
21st to endDay
8%5%33%37%14%2
630
July1st to 10thDay
9%318%36%27%8%
621
11th to 20thDay
5%322%40%22%8%
618
21st to endDay
8%217%43%28%3
684
August1st to 10thDay
7%221%42%23%5%
626
11th to 20thDay
8%319%42%24%3
615
21st to endDay
10%320%34%27%5%
671
September1st to 10thDay
14%424%35%20%3
338
11th to 20thDay
6%6%27%36%21%5%
270
21st to endDay
13%9%32%29%15%3
270
October1st to 10thDay
24%7%24%26%13%6%
270
11th to 20thDay
11%15%41%22%10%1
270
21st to endDay
17%15%38%19%9%1
297
November1st to 10thDay
15%15%37%23%7%3
270
11th to 20thDay
12%16%43%22%7%
270
21st to endDay
21%11%32%26%9%
270
December1st to 10thDay
8%14%41%29%7%1
270
11th to 20thDay
17%11%38%26%8%
270
21st to endDay
18%17%43%20%2
297
January1st to 10thNight
12%12%38%30%7%
950
11th to 20thNight
14%12%39%28%6%
950
21st to endNight
14%9%41%30%5%
1045
February1st to 10thNight
16%10%42%27%4
950
11th to 20thNight
12%13%41%30%4
872
21st to endNight
13%14%43%24%5%
628
March1st to 10thNight
13%14%39%27%6%
622
11th to 20thNight
18%9%40%27%5%
570
21st to endNight
21%11%39%24%6%
600
April1st to 10thNight
16%14%42%23%5%
540
11th to 20thNight
14%15%40%27%41
533
21st to endNight
19%12%34%26%8%1
540
May1st to 10thNight
17%8%35%30%10%
540
11th to 20thNight
14%10%33%34%9%1
531
21st to endNight
15%9%30%32%13%1
584
June1st to 10thNight
5%5%26%47%18%
540
11th to 20thNight
7%433%43%14%
540
21st to endNight
4436%42%14%
540
July1st to 10thNight
7%216%43%30%1
525
11th to 20thNight
3118%51%25%1
522
21st to endNight
3116%55%24%1
591
August1st to 10thNight
5%217%52%21%2
537
11th to 20thNight
6%219%49%22%1
534
21st to endNight
9%222%40%24%3
594
September1st to 10thNight
10%328%40%19%1
540
11th to 20thNight
9%229%43%16%1
540
21st to endNight
11%5%35%33%15%1
540
October1st to 10thNight
16%6%32%32%12%2
634
11th to 20thNight
16%10%38%30%8%
720
21st to endNight
17%11%32%31%9%
792
November1st to 10thNight
8%11%36%35%9%
920
11th to 20thNight
13%11%41%29%7%
950
21st to endNight
14%13%36%28%9%1
950
December1st to 10thNight
13%12%41%29%6%1
950
11th to 20thNight
15%11%34%33%7%
950
21st to endNight
19%12%37%28%5%
1045
Page generated at 2024-03-19 22:31:08. Version ac07

Copyright © 2024 Attilla Danko.


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