LoneStar Gazer Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the LoneStar Gazer Observatory clear sky chart from 2005-11-06 to 2024-12-24.

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%
24857
24%
96229
16%
24575
54%
24575
26%
53960

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
36%
941
31%
3981
12%
926
46%
926
25%
2119
January11th to 20thNight
33%
947
36%
3882
11%
930
42%
930
27%
1753
January21st to endNight
32%
956
20%
4325
11%
943
45%
943
18%
2635
February1st to 10thNight
28%
760
27%
2280
10%
760
42%
760
24%
1416
February11th to 20thNight
25%
744
23%
2218
8%
740
37%
740
26%
1363
February21st to endNight
18%
628
25%
1884
5%
628
34%
628
24%
1177
March1st to 10thNight
24%
579
25%
3402
10%
566
40%
566
13%
1964
March11th to 20thNight
28%
564
18%
3468
13%
550
40%
550
11%
2297
March21st to endNight
26%
624
16%
3701
13%
605
42%
605
14%
2157
April1st to 10thNight
27%
570
24%
2090
13%
570
43%
570
23%
1220
April11th to 20thNight
24%
563
21%
2063
11%
563
40%
563
21%
1256
April21st to endNight
27%
570
27%
1743
12%
570
45%
570
27%
1081
May1st to 10thNight
31%
570
22%
2834
14%
559
44%
559
15%
1863
May11th to 20thNight
41%
557
18%
2749
19%
541
50%
541
21%
1461
May21st to endNight
43%
613
14%
3079
14%
593
56%
593
19%
1758
June1st to 10thNight
64%
570
25%
1710
22%
570
72%
570
46%
886
June11th to 20thNight
55%
570
23%
1710
21%
570
63%
570
45%
898
June21st to endNight
65%
570
23%
1710
24%
570
70%
570
40%
965
July1st to 10thNight
65%
539
21%
2621
17%
535
71%
535
27%
1205
July11th to 20thNight
75%
540
22%
2522
27%
533
83%
533
33%
1198
July21st to endNight
74%
614
17%
2901
26%
569
81%
569
24%
1710
August1st to 10thNight
86%
547
44%
2386
32%
544
89%
544
56%
813
August11th to 20thNight
75%
546
19%
2725
27%
544
78%
544
33%
1078
August21st to endNight
77%
606
15%
3321
23%
605
79%
605
24%
1595
September1st to 10thNight
70%
570
23%
2090
26%
570
74%
570
32%
1157
September11th to 20thNight
66%
570
20%
2090
22%
570
69%
570
28%
1229
September21st to endNight
68%
570
27%
2090
26%
570
73%
570
35%
1084
October1st to 10thNight
71%
570
33%
2077
35%
550
74%
550
37%
1057
October11th to 20thNight
54%
700
29%
2356
20%
680
62%
680
34%
1288
October21st to endNight
47%
836
27%
2798
18%
814
55%
814
29%
1712
November1st to 10thNight
50%
780
28%
2340
18%
780
56%
780
33%
1414
November11th to 20thNight
46%
915
26%
2515
13%
915
54%
915
38%
1469
November21st to endNight
37%
1000
28%
2600
12%
1000
45%
1000
31%
1688
December1st to 10thNight
37%
1000
30%
2600
14%
1000
46%
1000
33%
1662
December11th to 20thNight
33%
999
25%
3014
11%
998
40%
998
25%
1937
December21st to endNight
36%
1059
17%
4354
12%
1044
44%
1044
23%
2395

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%6%25%44445%7%47%
101502
Night
13%6%25%33335%7%51%
98715
TransparencyDay
34%6%10%21%20%9%
105309
Night
32%5%11%20%20%11%
103034
SeeingDay
14%9%23%30%21%5%
15029
Night
16%8%27%34%14%1
24999

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
13%9%25%333245%51%
2847
11th to 20thDay
17%5%12322245%56%
2850
21st to endDay
18%8%37%332237%44%
3295
February1st to 10thDay
20%7%25%33324446%
1900
11th to 20thDay
17%8%3433335%5%46%
1849
21st to endDay
19%6%24323345%49%
1570
March1st to 10thDay
16%8%37%444345%42%
3422
11th to 20thDay
20%10%38%5%4445%5%33%
3480
21st to endDay
13%8%26%44445%6%44%
3814
April1st to 10thDay
15%8%26%44435%6%42%
2090
11th to 20thDay
17%8%36%434346%43%
2066
21st to endDay
15%6%25%5%4435%6%46%
2432
May1st to 10thDay
23%8%36%5%445%6%7%30%
4082
11th to 20thDay
16%6%26%44435%7%44%
4082
21st to endDay
12%6%37%5%5%7%6%8%10%34%
4477
June1st to 10thDay
5%426%5%45%47%8%50%
2470
11th to 20thDay
8%315%445%5%7%9%48%
2470
21st to endDay
7%6%25%5%6%5%5%8%9%41%
2470
July1st to 10thDay
6%425%5%45%46%9%50%
4120
11th to 20thDay
4315%34447%11%52%
4120
21st to endDay
10%6%36%5%46%5%6%10%39%
4465
August1st to 10thDay
111223335%8%72%
4104
11th to 20thDay
321333446%10%60%
3800
21st to endDay
4315%45%5%5%7%12%49%
3988
September1st to 10thDay
8%5%26%5%45%46%8%45%
2090
11th to 20thDay
12%5%27%445%47%7%43%
2090
21st to endDay
7%425%446%36%8%53%
2090
October1st to 10thDay
6%5%1434435%7%59%
2090
11th to 20thDay
12%425%433345%55%
1938
21st to endDay
11%5%14333245%60%
2090
November1st to 10thDay
15%7%25%33445%6%47%
1958
11th to 20thDay
10%6%26%443346%53%
1880
21st to endDay
16%7%25%334345%47%
1800
December1st to 10thDay
15%8%35%33335%5%48%
1800
11th to 20thDay
17%7%26%43435%445%
2251
21st to endDay
16%6%2422333454%
3162
January1st to 10thNight
19%6%23222235%54%
4108
11th to 20thNight
14%41322222465%
4120
21st to endNight
19%7%37%433336%43%
4400
February1st to 10thNight
20%7%25%233236%48%
2280
11th to 20thNight
20%6%25%332245%49%
2218
21st to endNight
20%6%24333245%47%
1884
March1st to 10thNight
17%8%26%44435%6%41%
3430
11th to 20thNight
22%9%27%5%4445%5%34%
3480
21st to endNight
14%8%37%5%3435%5%43%
3817
April1st to 10thNight
14%7%25%34436%7%47%
2090
11th to 20thNight
19%6%25%33335%5%44%
2063
21st to endNight
16%6%35%334336%47%
1743
May1st to 10thNight
25%9%26%33335%5%36%
2823
11th to 20thNight
11%6%35%33435%6%50%
2823
21st to endNight
13%6%25%345%46%8%42%
3090
June1st to 10thNight
5%31333336%11%59%
1710
11th to 20thNight
5%22433445%10%57%
1710
21st to endNight
7%5%1443436%10%54%
1710
July1st to 10thNight
5%31433446%10%56%
2850
11th to 20thNight
331443337%11%57%
2850
21st to endNight
9%7%26%3445%6%10%43%
3098
August1st to 10thNight
11222225%8%77%
2836
11th to 20thNight
321323346%11%61%
3022
21st to endNight
431434446%11%56%
3673
September1st to 10thNight
8%5%25%445%35%8%51%
2090
11th to 20thNight
10%7%26%5%4436%8%46%
2090
21st to endNight
8%41434436%8%55%
2090
October1st to 10thNight
7%314333346%63%
2090
11th to 20thNight
12%5%14333345%56%
2220
21st to endNight
14%42332333460%
2508
November1st to 10thNight
15%6%25%333246%52%
2340
11th to 20thNight
10%5%1433325%6%57%
2515
21st to endNight
17%5%25%334246%48%
2600
December1st to 10thNight
15%6%25%333245%51%
2600
11th to 20thNight
16%9%35%333345%47%
3166
21st to endNight
19%6%2322223454%
4578

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
36%35%18%25%14%
2848
11th to 20thDay
32%37%15%30%14%
2850
21st to endDay
42%36%10%28%12%
3295
February1st to 10thDay
42%46%13%21%14%
1900
11th to 20thDay
41%38%16%20%12%
1859
21st to endDay
40%36%18%19%15%
1570
March1st to 10thDay
43%48%13%21%11%
3422
11th to 20thDay
51%7%8%9%16%8%
3480
21st to endDay
38%6%10%14%23%9%
3814
April1st to 10thDay
42%5%8%17%15%13%
2090
11th to 20thDay
43%6%7%15%19%11%
2066
21st to endDay
39%6%6%20%20%9%
2432
May1st to 10thDay
52%7%10%14%13%5%
4120
11th to 20thDay
40%6%9%17%23%5%
4086
21st to endDay
39%11%13%25%10%2
4489
June1st to 10thDay
29%8%13%27%19%4
2470
11th to 20thDay
30%7%13%26%17%6%
2470
21st to endDay
35%9%12%23%18%3
2470
July1st to 10thDay
30%7%17%38%8%1
4056
11th to 20thDay
25%6%17%33%17%2
4051
21st to endDay
37%8%18%28%9%1
4325
August1st to 10thDay
12%411%39%32%1
4090
11th to 20thDay
20%5%21%39%13%3
3838
21st to endDay
26%9%20%25%18%2
3987
September1st to 10thDay
35%7%10%22%16%10%
2090
11th to 20thDay
38%8%11%19%18%6%
2090
21st to endDay
29%7%9%21%19%14%
2090
October1st to 10thDay
16%36%12%25%38%
3480
11th to 20thDay
21%38%19%29%20%
3204
21st to endDay
25%4420%33%14%
3428
November1st to 10thDay
37%6%9%17%21%11%
1958
11th to 20thDay
34%47%18%21%16%
1880
21st to endDay
40%46%17%20%14%
1800
December1st to 10thDay
39%49%19%22%9%
1800
11th to 20thDay
41%6%7%12%22%13%
2249
21st to endDay
35%45%14%28%14%
3162
January1st to 10thNight
34%36%15%24%17%
4108
11th to 20thNight
27%25%16%30%20%
4120
21st to endNight
44%35%12%25%11%
4400
February1st to 10thNight
40%46%13%20%17%
2280
11th to 20thNight
39%47%16%20%15%
2218
21st to endNight
41%46%14%18%17%
1884
March1st to 10thNight
43%6%9%14%19%10%
3430
11th to 20thNight
51%6%9%10%14%9%
3480
21st to endNight
42%6%9%15%20%9%
3817
April1st to 10thNight
37%6%8%17%17%15%
2090
11th to 20thNight
41%5%10%14%16%15%
2063
21st to endNight
40%49%19%19%9%
1743
May1st to 10thNight
49%6%9%16%14%6%
2850
11th to 20thNight
33%8%10%25%17%8%
2824
21st to endNight
36%9%13%28%9%4
3099
June1st to 10thNight
21%7%17%29%23%3
1710
11th to 20thNight
22%6%16%29%21%6%
1710
21st to endNight
27%7%16%29%18%3
1710
July1st to 10thNight
23%8%26%36%7%1
2805
11th to 20thNight
21%7%19%36%16%1
2796
21st to endNight
37%6%22%28%8%
2999
August1st to 10thNight
8%414%43%29%1
2826
11th to 20thNight
18%5%29%33%12%2
3049
21st to endNight
23%10%21%27%17%2
3673
September1st to 10thNight
30%7%13%24%17%8%
2090
11th to 20thNight
35%7%14%22%15%7%
2090
21st to endNight
27%6%13%22%18%13%
2090
October1st to 10thNight
15%46%15%20%41%
3480
11th to 20thNight
20%39%16%31%21%
3680
21st to endNight
25%35%19%32%16%
4120
November1st to 10thNight
35%5%8%17%22%13%
2340
11th to 20thNight
30%5%8%20%22%17%
2515
21st to endNight
39%47%17%18%15%
2600
December1st to 10thNight
37%48%20%20%11%
2600
11th to 20thNight
41%46%11%22%17%
3167
21st to endNight
36%35%14%29%13%
4578

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
19%17%34%24%31
270
11th to 20thDay
24%16%29%24%6%1
270
21st to endDay
21%20%32%22%6%
297
February1st to 10thDay
29%17%31%16%7%
270
11th to 20thDay
26%21%35%16%11
270
21st to endDay
27%25%33%14%1
225
March1st to 10thDay
23%22%35%17%3
270
11th to 20thDay
21%24%33%16%6%
270
21st to endDay
18%22%39%17%5%
297
April1st to 10thDay
23%20%39%14%4
270
11th to 20thDay
20%23%32%18%7%
264
21st to endDay
19%15%38%20%7%
612
May1st to 10thDay
17%13%37%25%7%
653
11th to 20thDay
20%7%27%32%11%2
675
21st to endDay
18%7%28%33%13%2
734
June1st to 10thDay
7%318%39%27%6%
680
11th to 20thDay
9%218%46%20%5%
680
21st to endDay
7%215%36%31%9%
680
July1st to 10thDay
7%210%42%30%10%
671
11th to 20thDay
48%39%42%7%
668
21st to endDay
6%16%37%43%8%
739
August1st to 10thDay
218%36%43%11%
676
11th to 20thDay
6%6%39%40%10%
527
21st to endDay
6%9%30%36%18%
425
September1st to 10thDay
10%8%26%41%15%
300
11th to 20thDay
10%9%28%43%10%
300
21st to endDay
10%28%35%35%11%
300
October1st to 10thDay
4318%38%30%7%
300
11th to 20thDay
11%6%28%31%21%4
300
21st to endDay
19%15%23%25%15%3
330
November1st to 10thDay
22%7%27%30%9%4
300
11th to 20thDay
17%13%30%24%14%2
300
21st to endDay
22%18%33%16%10%1
300
December1st to 10thDay
18%12%36%21%10%3
300
11th to 20thDay
20%16%35%21%7%
300
21st to endDay
20%13%37%19%9%1
306
January1st to 10thNight
20%11%30%31%8%1
950
11th to 20thNight
21%11%30%30%7%
950
21st to endNight
20%13%31%30%6%
965
February1st to 10thNight
25%12%31%26%5%
760
11th to 20thNight
25%13%35%25%2
744
21st to endNight
26%14%40%19%1
628
March1st to 10thNight
24%13%36%24%3
581
11th to 20thNight
22%11%34%29%4
570
21st to endNight
17%15%41%25%3
627
April1st to 10thNight
16%13%40%28%2
570
11th to 20thNight
22%13%39%22%4
563
21st to endNight
18%11%42%21%8%
570
May1st to 10thNight
17%11%38%28%5%
570
11th to 20thNight
14%7%34%33%11%1
561
21st to endNight
14%6%34%33%13%
617
June1st to 10thNight
6%224%45%21%2
570
11th to 20thNight
5%234%46%12%1
570
21st to endNight
7%219%45%24%2
570
July1st to 10thNight
7%117%43%28%4
555
11th to 20thNight
414%53%27%2
552
21st to endNight
5%13%50%28%3
624
August1st to 10thNight
19%57%28%4
567
11th to 20thNight
6%110%51%29%4
564
21st to endNight
7%7%48%33%5%
627
September1st to 10thNight
10%111%41%32%6%
570
11th to 20thNight
12%210%41%32%4
570
21st to endNight
12%113%36%36%3
570
October1st to 10thNight
7%215%45%27%4
570
11th to 20thNight
14%424%37%19%2
700
21st to endNight
16%10%25%29%19%1
836
November1st to 10thNight
16%6%23%38%16%1
780
11th to 20thNight
14%8%29%34%14%1
915
21st to endNight
21%10%29%28%12%1
1000
December1st to 10thNight
20%8%31%31%10%1
1000
11th to 20thNight
24%10%29%31%6%
1000
21st to endNight
22%10%28%32%8%
1063
Page generated at 2024-12-21 03:13:51. Version ac07

Copyright © 2024 Attilla Danko.


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