Teterville
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Teterville clear sky chart from 2005-11-06 to 2024-02-15.

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%
24577
25%
79671
14%
24467
50%
24467
31%
45782

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
30%
944
26%
4018
9%
926
44%
926
20%
2447
January11th to 20thNight
27%
949
26%
4004
9%
930
39%
930
21%
2270
January21st to endNight
27%
1036
19%
4469
9%
1023
41%
1023
20%
2688
February1st to 10thNight
23%
950
21%
2470
6%
950
32%
950
28%
1616
February11th to 20thNight
25%
804
21%
2235
7%
800
35%
800
28%
1392
February21st to endNight
26%
592
29%
1776
9%
592
41%
592
30%
1031
March1st to 10thNight
29%
550
26%
1990
13%
550
45%
550
29%
1078
March11th to 20thNight
29%
540
22%
1980
14%
540
41%
540
24%
1123
March21st to endNight
23%
594
17%
2178
8%
594
36%
594
17%
1407
April1st to 10thNight
24%
540
22%
1974
11%
540
41%
540
28%
1029
April11th to 20thNight
27%
533
23%
1720
12%
533
43%
533
27%
1005
April21st to endNight
28%
540
23%
1620
11%
540
44%
540
28%
962
May1st to 10thNight
32%
540
18%
1620
11%
540
43%
540
26%
1048
May11th to 20thNight
42%
531
21%
1594
18%
531
49%
531
32%
946
May21st to endNight
45%
584
18%
1745
12%
582
54%
582
31%
1058
June1st to 10thNight
58%
540
20%
1620
13%
540
65%
540
43%
869
June11th to 20thNight
51%
540
20%
1620
11%
540
58%
540
41%
880
June21st to endNight
52%
540
23%
1620
15%
540
59%
540
45%
846
July1st to 10thNight
68%
525
19%
1575
16%
525
71%
525
42%
860
July11th to 20thNight
74%
522
25%
1566
23%
522
79%
522
52%
765
July21st to endNight
66%
591
23%
1673
22%
558
69%
558
37%
945
August1st to 10thNight
68%
537
22%
1601
23%
534
73%
534
42%
860
August11th to 20thNight
66%
534
28%
1600
31%
534
71%
534
41%
878
August21st to endNight
73%
594
30%
1854
33%
594
76%
594
47%
926
September1st to 10thNight
62%
540
27%
1936
28%
540
68%
540
39%
971
September11th to 20thNight
55%
540
27%
1980
25%
540
63%
540
32%
1048
September21st to endNight
55%
540
33%
1980
30%
540
63%
540
39%
941
October1st to 10thNight
48%
628
29%
2068
21%
628
55%
628
35%
1118
October11th to 20thNight
35%
720
31%
2160
13%
720
48%
720
39%
1162
October21st to endNight
36%
792
30%
2376
13%
792
49%
792
33%
1336
November1st to 10thNight
38%
825
33%
2305
13%
825
53%
825
44%
1237
November11th to 20thNight
34%
950
30%
2470
10%
950
47%
950
40%
1417
November21st to endNight
36%
950
29%
2470
12%
950
47%
950
37%
1471
December1st to 10thNight
33%
950
27%
2470
10%
950
45%
950
35%
1495
December11th to 20thNight
29%
949
29%
2876
9%
948
43%
948
28%
1698
December21st to endNight
27%
1043
18%
4458
10%
1026
42%
1026
17%
2959

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%6%35%5%3445%7%47%
78761
Night
10%6%25%43445%7%51%
80380
TransparencyDay
37%412%26%18%3
78485
Night
34%312%27%20%4
80176
SeeingDay
15%9%29%29%16%3
14525
Night
13%10%32%32%12%1
24596

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
10%8%37%8%45%5%5%6%39%
2847
11th to 20thDay
9%9%37%6%6%7%447%38%
2850
21st to endDay
10%13%49%5%23336%41%
3135
February1st to 10thDay
12%10%36%6%23347%43%
1710
11th to 20thDay
9%7%37%5%3445%7%45%
1724
21st to endDay
11%7%35%5%3446%6%45%
1480
March1st to 10thDay
10%7%46%5%34447%46%
1968
11th to 20thDay
18%8%34323346%45%
1980
21st to endDay
18%10%46%5%2445%5%36%
2178
April1st to 10thDay
12%6%35%43445%6%49%
1984
11th to 20thDay
14%7%36%5%34446%43%
2186
21st to endDay
17%7%35%5%34346%41%
2340
May1st to 10thDay
16%9%35%5%25%5%5%7%38%
2340
11th to 20thDay
15%6%345%3445%8%43%
2302
21st to endDay
15%7%37%6%46%5%6%8%34%
2531
June1st to 10thDay
5%325%5%35%5%7%9%52%
2340
11th to 20thDay
8%3245%35%45%9%51%
2340
21st to endDay
6%32343446%10%56%
2340
July1st to 10thDay
9%5%245%35%6%8%9%44%
2340
11th to 20thDay
5%3134346%7%8%55%
2340
21st to endDay
8%5%25%6%35%6%6%9%44%
2546
August1st to 10thDay
8%4245%35%6%7%10%47%
2328
11th to 20thDay
8%3245%36%6%5%8%51%
2301
21st to endDay
6%3244245%6%9%55%
2502
September1st to 10thDay
12%5%2442445%6%53%
2020
11th to 20thDay
11%42442445%7%52%
1980
21st to endDay
8%42442445%6%56%
1980
October1st to 10thDay
10%6%25%4335%5%7%52%
1872
11th to 20thDay
10%413323346%61%
1800
21st to endDay
14%6%24423335%54%
1980
November1st to 10thDay
9%424423347%59%
1771
11th to 20thDay
9%5%25%423346%58%
1710
21st to endDay
14%5%24422336%56%
1710
December1st to 10thDay
10%6%344245%5%8%50%
1710
11th to 20thDay
11%7%36%5%45%446%45%
2161
21st to endDay
13%8%6%15%6%345%5%6%29%
3135
January1st to 10thNight
8%8%410%6%34345%45%
4108
11th to 20thNight
6%6%36%6%46%6%5%5%47%
4120
21st to endNight
15%11%35%323335%46%
4532
February1st to 10thNight
11%8%36%43445%7%44%
2470
11th to 20thNight
13%7%34424446%48%
2234
21st to endNight
10%7%35%42445%5%51%
1776
March1st to 10thNight
11%5%3442445%7%51%
1990
11th to 20thNight
15%6%2432435%7%49%
1980
21st to endNight
18%9%36%5%3445%5%39%
2178
April1st to 10thNight
11%425%423347%54%
1974
11th to 20thNight
13%6%24434348%48%
1720
21st to endNight
14%6%2442436%7%48%
1620
May1st to 10thNight
16%6%36%43445%7%42%
1620
11th to 20thNight
13%6%1442445%6%50%
1593
21st to endNight
9%5%245%345%7%10%45%
1745
June1st to 10thNight
5%224335%5%6%11%54%
1620
11th to 20thNight
43235%45%6%6%10%53%
1620
21st to endNight
6%213435%45%7%60%
1620
July1st to 10thNight
7%3244345%7%10%52%
1620
11th to 20thNight
321332445%11%61%
1620
21st to endNight
7%4146%35%5%7%10%48%
1772
August1st to 10thNight
5%3244345%9%10%51%
1611
11th to 20thNight
6%315%5%345%6%8%55%
1600
21st to endNight
5%31442435%8%61%
1854
September1st to 10thNight
10%414313446%60%
1936
11th to 20thNight
10%425%5%33347%54%
1980
21st to endNight
7%423423346%61%
1980
October1st to 10thNight
12%42442435%6%55%
2068
11th to 20thNight
12%423323335%60%
2160
21st to endNight
13%6%24333335%56%
2376
November1st to 10thNight
8%424323345%63%
2305
11th to 20thNight
9%5%24323446%58%
2470
21st to endNight
12%7%24312345%56%
2470
December1st to 10thNight
9%7%25%4235%5%7%52%
2470
11th to 20thNight
10%5%35%5%3445%7%50%
3036
21st to endNight
16%8%49%5%35%345%38%
4532

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
45%411%24%16%1
2848
11th to 20thDay
49%311%23%11%4
2850
21st to endDay
47%211%21%18%1
3135
February1st to 10thDay
42%411%26%13%4
1710
11th to 20thDay
40%312%27%14%4
1733
21st to endDay
38%39%25%20%5%
1480
March1st to 10thDay
40%39%23%19%7%
1968
11th to 20thDay
42%39%24%18%4
1980
21st to endDay
48%5%11%23%9%3
2178
April1st to 10thDay
36%412%25%20%4
1984
11th to 20thDay
43%310%26%16%3
2186
21st to endDay
45%310%29%12%1
2340
May1st to 10thDay
47%412%21%15%2
2340
11th to 20thDay
41%414%27%14%
2306
21st to endDay
47%6%14%22%9%2
2531
June1st to 10thDay
28%5%17%31%16%3
2340
11th to 20thDay
31%413%29%20%3
2340
21st to endDay
24%415%30%22%5%
2340
July1st to 10thDay
33%6%16%27%15%3
2276
11th to 20thDay
23%6%16%29%21%5%
2271
21st to endDay
33%5%15%29%17%1
2405
August1st to 10thDay
30%7%18%29%14%2
2314
11th to 20thDay
31%5%11%32%18%3
2301
21st to endDay
26%5%14%26%20%8%
2502
September1st to 10thDay
33%313%26%19%7%
2020
11th to 20thDay
31%410%30%23%3
1980
21st to endDay
29%39%26%28%4
1980
October1st to 10thDay
33%312%25%25%3
1872
11th to 20thDay
26%38%28%28%7%
1800
21st to endDay
35%310%25%20%8%
1980
November1st to 10thDay
28%211%30%23%7%
1771
11th to 20thDay
30%28%28%27%5%
1710
21st to endDay
32%39%29%24%4
1710
December1st to 10thDay
33%312%32%18%2
1710
11th to 20thDay
40%48%27%18%3
2159
21st to endDay
55%48%21%10%2
3135
January1st to 10thNight
43%39%28%16%2
4108
11th to 20thNight
37%412%26%18%2
4120
21st to endNight
43%211%23%19%2
4532
February1st to 10thNight
41%312%24%16%5%
2470
11th to 20thNight
38%312%26%17%4
2235
21st to endNight
34%39%24%21%8%
1776
March1st to 10thNight
33%310%24%21%8%
1990
11th to 20thNight
37%411%23%20%5%
1980
21st to endNight
47%411%22%14%2
2178
April1st to 10thNight
32%312%24%24%6%
1974
11th to 20thNight
37%312%25%20%4
1720
21st to endNight
37%314%24%18%4
1620
May1st to 10thNight
42%413%22%16%2
1620
11th to 20thNight
36%316%28%16%1
1594
21st to endNight
34%7%20%26%11%2
1746
June1st to 10thNight
24%6%21%32%14%3
1620
11th to 20thNight
27%5%16%31%19%3
1620
21st to endNight
24%5%13%33%20%6%
1620
July1st to 10thNight
27%415%31%18%4
1575
11th to 20thNight
20%314%33%24%6%
1566
21st to endNight
30%5%15%31%18%1
1673
August1st to 10thNight
26%5%18%33%14%4
1601
11th to 20thNight
28%412%31%23%3
1600
21st to endNight
23%313%27%26%8%
1854
September1st to 10thNight
27%311%28%21%9%
1936
11th to 20thNight
31%411%23%26%5%
1980
21st to endNight
24%38%27%31%6%
1980
October1st to 10thNight
32%310%22%26%8%
2068
11th to 20thNight
27%46%29%26%8%
2160
21st to endNight
32%38%22%28%7%
2376
November1st to 10thNight
26%29%30%25%9%
2305
11th to 20thNight
28%29%28%28%5%
2470
21st to endNight
32%210%26%23%7%
2470
December1st to 10thNight
33%313%28%21%2
2470
11th to 20thNight
34%38%31%20%3
3037
21st to endNight
48%49%24%13%3
4532

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
20%16%32%25%6%1
270
11th to 20thDay
22%19%38%19%3
270
21st to endDay
13%13%49%20%31
297
February1st to 10thDay
23%18%40%17%11
270
11th to 20thDay
17%17%42%20%4
252
21st to endDay
21%24%35%18%11
198
March1st to 10thDay
19%17%43%19%3
240
11th to 20thDay
28%14%34%20%4
240
21st to endDay
28%19%38%12%2
264
April1st to 10thDay
20%22%39%14%5%
244
11th to 20thDay
19%17%38%20%4
464
21st to endDay
24%12%36%20%6%2
600
May1st to 10thDay
20%12%39%19%9%1
603
11th to 20thDay
21%10%27%29%11%2
625
21st to endDay
18%7%32%24%15%3
679
June1st to 10thDay
6%423%36%24%6%
630
11th to 20thDay
8%332%37%16%3
630
21st to endDay
7%5%30%40%16%2
630
July1st to 10thDay
11%312%36%30%9%
621
11th to 20thDay
6%214%41%30%6%
618
21st to endDay
8%113%39%32%8%
684
August1st to 10thDay
10%116%40%28%4
626
11th to 20thDay
8%215%41%30%5%
615
21st to endDay
8%213%38%33%7%
621
September1st to 10thDay
13%113%39%31%4
310
11th to 20thDay
7%320%41%21%8%
270
21st to endDay
16%327%36%15%4
270
October1st to 10thDay
14%7%31%25%16%7%
270
11th to 20thDay
9%14%49%21%7%
270
21st to endDay
24%11%37%21%6%2
297
November1st to 10thDay
16%12%34%26%11%1
270
11th to 20thDay
17%21%34%17%10%1
270
21st to endDay
21%11%39%21%7%
270
December1st to 10thDay
13%12%41%23%7%3
270
11th to 20thDay
16%16%35%25%8%
270
21st to endDay
19%21%41%19%1
297
January1st to 10thNight
13%13%39%28%7%
950
11th to 20thNight
14%15%38%27%5%1
950
21st to endNight
14%14%40%28%4
1045
February1st to 10thNight
16%15%41%24%4
950
11th to 20thNight
17%15%38%27%3
804
21st to endNight
15%14%41%26%4
592
March1st to 10thNight
15%13%40%27%5%
550
11th to 20thNight
20%12%35%26%6%
540
21st to endNight
23%15%35%23%5%
594
April1st to 10thNight
15%14%42%21%8%1
540
11th to 20thNight
17%15%37%26%4
533
21st to endNight
17%13%38%25%6%1
540
May1st to 10thNight
19%9%35%31%6%1
540
11th to 20thNight
18%7%28%33%14%1
531
21st to endNight
11%7%32%34%14%2
584
June1st to 10thNight
6%327%39%22%2
540
11th to 20thNight
6%434%41%16%
540
21st to endNight
7%134%44%14%
540
July1st to 10thNight
8%214%43%30%2
525
11th to 20thNight
3115%51%27%2
522
21st to endNight
7%113%43%32%3
591
August1st to 10thNight
8%115%45%30%2
537
11th to 20thNight
7%114%46%30%1
534
21st to endNight
6%114%42%34%3
594
September1st to 10thNight
11%219%43%21%4
540
11th to 20thNight
11%322%38%23%3
540
21st to endNight
9%5%25%41%17%2
540
October1st to 10thNight
14%428%31%20%2
628
11th to 20thNight
15%9%39%29%8%
720
21st to endNight
17%13%32%29%10%1
792
November1st to 10thNight
10%9%39%31%11%1
825
11th to 20thNight
12%14%37%29%7%1
950
21st to endNight
18%12%32%31%7%
950
December1st to 10thNight
14%12%35%32%6%1
950
11th to 20thNight
16%12%37%30%5%
950
21st to endNight
16%16%36%28%3
1045
Page generated at 2024-02-12 05:35:36. Version ac07

Copyright 2024 Attilla Danko


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