Buckingham
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Buckingham clear sky chart from 2005-11-06 to 2024-03-28.

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
31%
23489
20%
80643
10%
23395
43%
23395
20%
50724

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
17%
753
24%
4334
8%
737
37%
737
11%
2366
January11th to 20thNight
20%
760
23%
4304
6%
740
39%
740
11%
2488
January21st to endNight
18%
832
15%
4473
6%
814
38%
814
11%
2864
February1st to 10thNight
20%
760
19%
2470
7%
760
35%
760
18%
1595
February11th to 20thNight
13%
743
19%
2257
3%
740
32%
740
16%
1482
February21st to endNight
16%
628
24%
1884
7%
628
36%
628
19%
1228
March1st to 10thNight
21%
760
23%
2280
8%
760
39%
760
20%
1428
March11th to 20thNight
20%
760
22%
2102
8%
760
34%
760
20%
1404
March21st to endNight
20%
821
21%
2118
6%
821
32%
821
24%
1424
April1st to 10thNight
18%
720
19%
1800
3%
720
27%
720
22%
1239
April11th to 20thNight
25%
711
20%
1775
5%
711
31%
711
25%
1225
April21st to endNight
26%
720
20%
1800
5%
720
34%
720
25%
1219
May1st to 10thNight
25%
573
15%
1653
7%
573
31%
573
18%
1172
May11th to 20thNight
28%
354
18%
1416
10%
354
40%
354
17%
901
May21st to endNight
44%
388
14%
1551
13%
388
51%
388
19%
962
June1st to 10thNight
43%
360
18%
1440
16%
360
53%
360
21%
878
June11th to 20thNight
46%
360
15%
1440
15%
360
55%
360
20%
885
June21st to endNight
54%
360
16%
1440
16%
360
61%
360
24%
834
July1st to 10thNight
54%
350
13%
1400
14%
350
60%
350
18%
888
July11th to 20thNight
58%
348
16%
1392
19%
348
62%
348
24%
804
July21st to endNight
55%
406
18%
1498
17%
384
62%
384
24%
878
August1st to 10thNight
58%
537
16%
1600
10%
534
61%
534
28%
1020
August11th to 20thNight
55%
693
16%
1757
9%
693
56%
693
27%
1242
August21st to endNight
54%
792
17%
1980
8%
792
56%
792
30%
1348
September1st to 10thNight
45%
720
21%
1800
10%
720
51%
720
30%
1216
September11th to 20thNight
52%
720
29%
1836
18%
720
57%
720
37%
1134
September21st to endNight
44%
720
24%
1980
16%
720
52%
720
27%
1312
October1st to 10thNight
39%
720
17%
2142
12%
720
46%
720
24%
1409
October11th to 20thNight
39%
720
24%
2160
15%
720
51%
720
29%
1306
October21st to endNight
28%
792
24%
2453
13%
792
43%
792
23%
1545
November1st to 10thNight
35%
740
25%
2407
13%
740
52%
740
30%
1366
November11th to 20thNight
29%
760
25%
2470
13%
760
45%
760
22%
1511
November21st to endNight
27%
760
22%
2588
10%
760
44%
760
22%
1551
December1st to 10thNight
19%
760
19%
2660
6%
760
35%
760
15%
1711
December11th to 20thNight
21%
760
19%
3200
6%
759
37%
759
15%
1957
December21st to endNight
22%
828
14%
4783
8%
817
38%
817
10%
2932

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
16%6%35%5%35%5%5%7%40%
78728
Night
16%6%35%5%3445%6%43%
81259
TransparencyDay
42%6%12%22%15%2
78434
Night
42%5%11%23%16%3
81087
SeeingDay
23%14%29%21%10%3
14106
Night
20%13%31%26%9%1
23509

By Month

Percentage Cloud Cover NE (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
15%8%36%434445%46%
2517
11th to 20thDay
14%10%49%6%3445%6%35%
2552
21st to endDay
22%8%36%6%34446%35%
3124
February1st to 10thDay
17%7%26%6%25%5%5%7%39%
1710
11th to 20thDay
17%7%37%6%34346%40%
1810
21st to endDay
20%8%47%42445%5%38%
1570
March1st to 10thDay
15%6%35%6%34345%45%
1897
11th to 20thDay
15%6%37%6%4445%7%40%
2075
21st to endDay
21%7%26%43445%5%39%
2393
April1st to 10thDay
16%7%35%5%3445%6%41%
2160
11th to 20thDay
15%7%25%5%3446%7%42%
2134
21st to endDay
16%5%27%5%4446%7%39%
2160
May1st to 10thDay
19%7%35%6%345%6%7%34%
2321
11th to 20thDay
20%7%25%435%5%5%7%37%
2478
21st to endDay
14%7%35%5%45%46%8%39%
2725
June1st to 10thDay
14%5%25%5%45%6%7%9%37%
2520
11th to 20thDay
14%6%36%6%46%5%6%8%37%
2520
21st to endDay
12%5%25%5%46%5%6%9%41%
2520
July1st to 10thDay
11%5%26%6%36%6%6%9%39%
2520
11th to 20thDay
9%5%245%36%6%7%11%43%
2520
21st to endDay
11%6%36%6%45%6%6%9%37%
2728
August1st to 10thDay
11%425%6%46%6%8%9%40%
2327
11th to 20thDay
12%6%35%5%46%6%6%8%39%
2126
21st to endDay
14%5%35%5%345%6%8%41%
2376
September1st to 10thDay
15%5%25%5%335%6%8%42%
2160
11th to 20thDay
13%5%244235%5%8%50%
2124
21st to endDay
17%7%35%6%35%446%41%
1980
October1st to 10thDay
19%6%244245%5%7%42%
1814
11th to 20thDay
15%6%25%425%45%7%46%
1800
21st to endDay
20%7%2442445%6%43%
1900
November1st to 10thDay
14%6%25%333336%52%
1671
11th to 20thDay
17%5%244245%5%5%48%
1710
21st to endDay
15%6%25%4335%48%45%
1588
December1st to 10thDay
19%8%25%5%3445%8%38%
1520
11th to 20thDay
21%6%34434346%42%
1906
21st to endDay
17%6%46%6%46%5%5%7%34%
2772
January1st to 10thNight
16%7%25%434446%46%
4429
11th to 20thNight
17%9%35%5%33345%43%
4404
21st to endNight
24%9%35%424445%38%
4532
February1st to 10thNight
16%8%44434446%41%
2470
11th to 20thNight
18%8%35%5%3445%5%41%
2256
21st to endNight
18%8%35%423446%43%
1884
March1st to 10thNight
16%6%2442445%7%45%
2270
11th to 20thNight
16%7%35%5%3445%5%45%
2101
21st to endNight
18%6%36%433446%43%
2118
April1st to 10thNight
17%5%35%5%35%45%6%40%
1800
11th to 20thNight
15%6%36%5%25%5%5%6%41%
1775
21st to endNight
20%6%2433335%7%43%
1800
May1st to 10thNight
19%8%36%5%3445%6%35%
1653
11th to 20thNight
18%6%36%5%3446%6%39%
1415
21st to endNight
15%6%35%5%3445%8%42%
1550
June1st to 10thNight
17%6%2444446%6%43%
1440
11th to 20thNight
11%6%25%6%46%46%9%39%
1440
21st to endNight
11%425%5%45%6%5%10%45%
1440
July1st to 10thNight
11%5%25%5%5%6%6%6%10%38%
1440
11th to 20thNight
9%4345%36%6%8%10%43%
1440
21st to endNight
9%5%26%5%45%6%7%9%43%
1586
August1st to 10thNight
10%6%25%6%36%5%7%9%42%
1611
11th to 20thNight
10%7%37%5%45%6%6%8%38%
1757
21st to endNight
14%6%25%5%345%7%9%41%
1980
September1st to 10thNight
15%6%25%5%335%46%45%
1800
11th to 20thNight
12%5%34434347%53%
1836
21st to endNight
16%6%245%345%5%7%42%
1980
October1st to 10thNight
19%7%245%34345%44%
2142
11th to 20thNight
15%5%2443335%6%50%
2160
21st to endNight
19%7%35%423346%46%
2453
November1st to 10thNight
12%6%24423446%54%
2407
11th to 20thNight
18%6%34433445%48%
2470
21st to endNight
14%5%345%3446%8%44%
2588
December1st to 10thNight
20%6%35%43445%6%40%
2660
11th to 20thNight
18%5%25%5%345%5%7%41%
3288
21st to endNight
19%7%36%5%345%46%38%
4884

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
40%412%28%13%3
2518
11th to 20thDay
49%5%11%20%13%2
2552
21st to endDay
51%5%12%20%10%1
3124
February1st to 10thDay
45%5%14%23%11%2
1710
11th to 20thDay
46%49%22%16%3
1819
21st to endDay
48%5%11%21%12%4
1570
March1st to 10thDay
42%411%27%13%3
1900
11th to 20thDay
44%411%22%15%4
2075
21st to endDay
47%48%18%18%4
2393
April1st to 10thDay
43%6%10%21%15%5%
2160
11th to 20thDay
40%5%12%22%17%4
2134
21st to endDay
43%5%11%19%17%4
2160
May1st to 10thDay
48%6%10%17%16%3
2321
11th to 20thDay
46%6%10%21%14%2
2482
21st to endDay
43%7%13%21%14%2
2725
June1st to 10thDay
41%9%13%22%14%1
2520
11th to 20thDay
43%8%14%22%11%2
2520
21st to endDay
38%9%14%24%15%1
2520
July1st to 10thDay
40%9%12%22%14%2
2450
11th to 20thDay
33%9%14%26%16%2
2445
21st to endDay
41%8%12%20%17%2
2575
August1st to 10thDay
38%10%12%23%16%1
2314
11th to 20thDay
39%8%15%20%15%2
2126
21st to endDay
40%8%11%21%17%4
2376
September1st to 10thDay
40%6%11%19%20%3
2160
11th to 20thDay
33%5%11%24%24%4
2124
21st to endDay
45%5%8%18%21%3
1980
October1st to 10thDay
41%7%11%22%18%2
1814
11th to 20thDay
38%6%11%23%21%2
1800
21st to endDay
43%5%9%23%18%2
1900
November1st to 10thDay
36%312%25%20%3
1671
11th to 20thDay
38%5%11%23%21%3
1710
21st to endDay
37%5%13%30%12%3
1588
December1st to 10thDay
44%5%16%21%12%1
1520
11th to 20thDay
44%5%13%25%11%2
1906
21st to endDay
47%6%13%22%11%1
2772
January1st to 10thNight
41%410%30%12%3
4429
11th to 20thNight
45%313%25%12%2
4404
21st to endNight
50%38%25%12%2
4532
February1st to 10thNight
44%5%13%25%11%2
2470
11th to 20thNight
45%310%19%18%4
2258
21st to endNight
44%48%23%17%4
1884
March1st to 10thNight
39%5%10%25%17%4
2280
11th to 20thNight
43%5%9%22%18%4
2102
21st to endNight
43%410%18%19%6%
2118
April1st to 10thNight
43%5%11%20%16%4
1800
11th to 20thNight
42%6%9%20%20%3
1775
21st to endNight
41%5%9%20%19%5%
1800
May1st to 10thNight
48%7%9%17%17%2
1653
11th to 20thNight
45%7%12%15%18%3
1416
21st to endNight
41%8%16%19%14%2
1551
June1st to 10thNight
41%6%11%21%19%2
1440
11th to 20thNight
41%7%14%23%13%1
1440
21st to endNight
34%9%14%27%14%2
1440
July1st to 10thNight
39%12%13%20%14%2
1400
11th to 20thNight
33%10%16%24%15%2
1392
21st to endNight
34%10%16%23%15%2
1498
August1st to 10thNight
36%10%16%22%15%2
1600
11th to 20thNight
43%9%13%20%14%2
1757
21st to endNight
38%9%13%18%19%3
1980
September1st to 10thNight
40%6%11%20%20%3
1800
11th to 20thNight
33%5%10%21%26%4
1836
21st to endNight
41%5%7%22%22%2
1980
October1st to 10thNight
43%6%11%23%15%2
2142
11th to 20thNight
36%5%11%28%17%3
2160
21st to endNight
41%49%26%18%2
2453
November1st to 10thNight
33%413%24%21%5%
2407
11th to 20thNight
40%49%23%20%5%
2470
21st to endNight
39%413%27%15%2
2588
December1st to 10thNight
45%5%12%22%14%1
2660
11th to 20thNight
42%6%13%20%16%3
3288
21st to endNight
46%5%12%25%11%1
4884

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
32%22%31%13%31
180
11th to 20thDay
39%21%31%8%1
189
21st to endDay
29%24%30%13%4
297
February1st to 10thDay
30%26%33%8%3
270
11th to 20thDay
30%25%34%10%2
418
21st to endDay
32%22%31%12%3
382
March1st to 10thDay
30%19%32%15%4
460
11th to 20thDay
30%22%30%13%31
460
21st to endDay
28%24%29%12%5%1
490
April1st to 10thDay
31%22%27%14%5%1
420
11th to 20thDay
25%22%31%14%7%2
412
21st to endDay
26%20%35%14%41
420
May1st to 10thDay
32%16%29%14%6%2
423
11th to 20thDay
24%13%36%18%7%1
447
21st to endDay
19%8%26%28%16%3
485
June1st to 10thDay
16%12%32%24%14%3
450
11th to 20thDay
19%13%28%26%11%3
450
21st to endDay
16%11%30%28%12%3
450
July1st to 10thDay
12%7%23%31%19%8%
445
11th to 20thDay
9%5%25%34%23%4
444
21st to endDay
13%7%30%32%14%4
488
August1st to 10thDay
11%428%33%17%7%
446
11th to 20thDay
14%423%32%20%7%
439
21st to endDay
14%7%27%27%16%8%
495
September1st to 10thDay
18%9%25%24%17%8%
450
11th to 20thDay
16%6%27%27%14%10%
450
21st to endDay
24%12%24%24%11%6%
450
October1st to 10thDay
26%7%28%22%11%7%
450
11th to 20thDay
17%16%30%24%10%2
450
21st to endDay
24%15%33%15%10%2
455
November1st to 10thDay
21%11%33%22%10%3
365
11th to 20thDay
25%17%33%20%5%1
370
21st to endDay
24%18%38%15%5%
248
December1st to 10thDay
32%23%28%10%7%
180
11th to 20thDay
37%21%27%12%4
180
21st to endDay
31%18%30%15%6%1
198
January1st to 10thNight
21%22%34%20%3
760
11th to 20thNight
26%17%34%20%3
760
21st to endNight
21%19%37%22%2
836
February1st to 10thNight
21%17%36%24%2
760
11th to 20thNight
27%22%35%15%1
743
21st to endNight
26%19%36%17%2
628
March1st to 10thNight
25%20%31%21%3
760
11th to 20thNight
24%21%33%17%4
760
21st to endNight
22%16%38%19%5%
821
April1st to 10thNight
23%18%38%15%5%
720
11th to 20thNight
18%16%38%21%6%
711
21st to endNight
23%13%34%24%5%
720
May1st to 10thNight
24%14%32%24%6%
573
11th to 20thNight
20%10%36%26%7%
354
21st to endNight
16%8%24%37%13%2
389
June1st to 10thNight
18%6%28%35%13%
360
11th to 20thNight
12%6%27%41%13%
360
21st to endNight
10%424%49%12%1
360
July1st to 10thNight
12%323%41%18%2
350
11th to 20thNight
8%324%42%21%2
348
21st to endNight
9%227%42%18%1
406
August1st to 10thNight
13%118%42%23%2
537
11th to 20thNight
13%418%36%26%3
693
21st to endNight
15%419%37%23%2
792
September1st to 10thNight
18%423%35%17%3
720
11th to 20thNight
15%5%23%34%20%4
720
21st to endNight
20%6%24%30%18%1
720
October1st to 10thNight
23%8%25%23%17%4
720
11th to 20thNight
18%10%28%31%13%
720
21st to endNight
22%13%32%24%8%1
792
November1st to 10thNight
16%10%35%27%12%1
740
11th to 20thNight
23%15%28%26%8%
760
21st to endNight
16%18%34%25%6%1
760
December1st to 10thNight
27%16%32%18%5%1
760
11th to 20thNight
22%15%35%22%5%
760
21st to endNight
23%16%33%26%3
836
Page generated at 2024-03-24 23:37:04. Version ac07

Copyright © 2024 Attilla Danko.


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