Doughton Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Doughton Park clear sky chart from 2005-11-05 to 2018-03-21.

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
42%
16463
21%
49181
12%
16425
51%
16425
24%
31301

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
25%
778
23%
2522
8%
776
43%
776
20%
1521
January16th to endNight
22%
832
24%
2704
9%
832
40%
832
21%
1627
February1st to 15thNight
23%
761
22%
2447
8%
761
39%
761
19%
1496
February16th to endNight
18%
683
22%
2036
7%
683
33%
683
20%
1309
March1st to 15thNight
27%
780
23%
2145
9%
780
38%
780
22%
1383
March16th to endNight
27%
792
17%
2178
8%
792
35%
792
22%
1466
April1st to 15thNight
34%
718
20%
1916
7%
718
44%
718
26%
1211
April16th to endNight
39%
603
20%
1683
9%
603
47%
603
25%
1100
May1st to 15thNight
39%
540
15%
1620
7%
540
46%
540
22%
1114
May16th to endNight
55%
561
14%
1684
9%
561
57%
561
25%
1115
June1st to 15thNight
63%
540
13%
1620
12%
540
65%
540
27%
1068
June16th to endNight
67%
540
16%
1620
13%
540
70%
540
31%
1025
July1st to 15thNight
67%
510
11%
1530
9%
510
68%
510
26%
1018
July16th to endNight
73%
564
13%
1595
11%
531
76%
531
30%
1014
August1st to 15thNight
61%
539
14%
1609
12%
536
62%
536
23%
1108
August16th to endNight
67%
645
18%
1791
15%
645
68%
645
27%
1240
September1st to 15thNight
60%
720
20%
1958
15%
720
62%
720
27%
1302
September16th to endNight
52%
717
19%
1980
15%
717
54%
717
24%
1352
October1st to 15thNight
48%
720
25%
2112
21%
720
55%
720
28%
1313
October16th to endNight
43%
768
33%
2304
21%
768
59%
768
33%
1302
November1st to 15thNight
46%
760
26%
2353
17%
760
57%
760
30%
1362
November16th to endNight
39%
780
27%
2535
18%
780
53%
780
27%
1444
December1st to 15thNight
31%
780
23%
2535
11%
780
45%
780
20%
1598
December16th to endNight
23%
832
21%
2704
8%
832
38%
832
16%
1813

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
14%5%25%5%35%5%5%7%38%
49656
Night
14%5%2442445%7%44%
49374
Cloud CoverDay
14%6%25%5%35%5%5%7%38%
49666
Night
14%5%2442445%7%44%
49378
TransparencyDay
43%8%12%18%14%3
49367
Night
37%7%13%20%16%3
49181
SeeingDay
19%11%21%21%16%10%
6197
Night
17%11%22%26%18%3
16470

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 15thDay
15%6%24435%5%35%42%
1746
16th to endDay
14%42442435%5%47%
1872
February1st to 15thDay
12%9%2443346%6%42%
1742
16th to endDay
15%7%345%34446%41%
1723
March1st to 15thDay
15%424424346%46%
2134
16th to endDay
18%7%25%5%24345%39%
2174
April1st to 15thDay
12%4144245%5%7%47%
2031
16th to endDay
16%5%345%35%447%38%
2287
May1st to 15thDay
17%6%25%5%35%6%5%8%32%
2331
16th to endDay
14%6%16%6%35%6%6%9%33%
2431
June1st to 15thDay
11%6%26%7%47%6%7%9%30%
2340
16th to endDay
9%336%7%46%6%7%10%33%
2340
July1st to 15thDay
12%6%36%7%47%7%7%8%27%
2340
16th to endDay
10%5%37%7%6%8%8%8%9%24%
2465
August1st to 15thDay
14%6%27%8%5%7%6%7%8%24%
2340
16th to endDay
12%7%36%7%46%6%7%9%28%
2399
September1st to 15thDay
15%6%26%6%35%6%5%7%35%
1999
16th to endDay
21%6%36%5%3445%6%34%
1980
October1st to 15thDay
17%413324345%48%
1848
16th to endDay
16%413313235%53%
1920
November1st to 15thDay
12%413323346%52%
1832
16th to endDay
15%424423345%49%
1755
December1st to 15thDay
14%7%34433447%42%
1755
16th to endDay
20%7%15%423346%38%
1872
January1st to 15thNight
14%423324445%48%
2522
16th to endNight
14%6%23324445%46%
2704
February1st to 15thNight
14%6%24433445%46%
2445
16th to endNight
13%5%25%425%5%5%7%42%
2036
March1st to 15thNight
14%4244345%45%45%
2133
16th to endNight
16%5%344245%45%42%
2178
April1st to 15thNight
11%6%1433435%8%45%
1916
16th to endNight
17%5%234145%5%7%43%
1683
May1st to 15thNight
17%7%245%3345%7%39%
1620
16th to endNight
14%425%4246%6%11%38%
1682
June1st to 15thNight
9%414426%6%7%11%40%
1620
16th to endNight
7%4244445%6%11%44%
1620
July1st to 15thNight
10%5%14435%5%8%11%39%
1620
16th to endNight
4425%5%36%6%7%12%39%
1703
August1st to 15thNight
15%425%5%26%5%6%8%37%
1620
16th to endNight
11%5%26%5%345%7%10%38%
1791
September1st to 15thNight
13%5%26%4245%6%7%42%
1958
16th to endNight
18%6%245%23445%42%
1980
October1st to 15thNight
16%5%14322346%48%
2112
16th to endNight
13%313313336%56%
2304
November1st to 15thNight
15%413323336%54%
2353
16th to endNight
14%413323346%52%
2535
December1st to 15thNight
16%6%25%324335%45%
2535
16th to endNight
21%8%25%42345%6%36%
2704

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
15%6%23435%445%43%
1746
16th to endDay
15%424424346%47%
1872
February1st to 15thDay
12%8%2442345%6%43%
1742
16th to endDay
15%6%35%434346%41%
1723
March1st to 15thDay
15%42442435%6%46%
2145
16th to endDay
18%7%24425%346%39%
2173
April1st to 15thDay
13%4134245%5%7%47%
2031
16th to endDay
17%5%245%3445%6%38%
2287
May1st to 15thDay
16%6%25%5%35%5%6%8%33%
2331
16th to endDay
14%6%16%6%445%6%9%33%
2431
June1st to 15thDay
11%6%26%7%47%6%7%9%31%
2340
16th to endDay
9%426%6%5%5%7%7%10%33%
2340
July1st to 15thDay
13%6%36%7%47%7%7%9%26%
2340
16th to endDay
10%6%37%7%5%8%8%8%9%24%
2465
August1st to 15thDay
14%7%27%8%5%7%6%7%8%24%
2340
16th to endDay
13%6%26%7%46%6%7%10%28%
2399
September1st to 15thDay
15%6%26%5%25%6%5%7%35%
1999
16th to endDay
21%6%26%5%3435%6%34%
1980
October1st to 15thDay
17%413324335%48%
1848
16th to endDay
16%414312235%53%
1920
November1st to 15thDay
12%423323346%52%
1832
16th to endDay
14%5%24413435%49%
1755
December1st to 15thDay
14%7%34434446%43%
1755
16th to endDay
21%6%25%424346%39%
1872
January1st to 15thNight
15%5%13324445%49%
2522
16th to endNight
14%6%23324446%46%
2704
February1st to 15thNight
13%6%24424445%46%
2438
16th to endNight
13%5%25%4245%5%7%43%
2036
March1st to 15thNight
14%5%24435%5%45%45%
2145
16th to endNight
16%6%24424446%42%
2178
April1st to 15thNight
12%5%2432435%8%46%
1916
16th to endNight
18%5%2331345%7%43%
1683
May1st to 15thNight
17%6%245%3345%7%39%
1619
16th to endNight
13%5%25%4145%7%11%37%
1682
June1st to 15thNight
9%424435%7%6%11%40%
1620
16th to endNight
7%4244345%7%10%44%
1620
July1st to 15thNight
11%424435%5%8%11%39%
1620
16th to endNight
4435%5%46%6%8%11%41%
1703
August1st to 15thNight
15%425%435%5%6%8%37%
1620
16th to endNight
11%5%25%5%345%6%10%37%
1791
September1st to 15thNight
13%5%25%32446%7%42%
1958
16th to endNight
19%5%245%24345%42%
1980
October1st to 15thNight
16%5%23313345%49%
2112
16th to endNight
13%313312335%57%
2304
November1st to 15thNight
15%5%12223236%54%
2353
16th to endNight
14%413313346%52%
2535
December1st to 15thNight
16%6%25%314345%45%
2535
16th to endNight
21%7%25%42445%7%35%
2704

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
41%7%9%19%18%4
1747
16th to endDay
37%49%25%17%5%
1872
February1st to 15thDay
38%6%12%21%16%3
1744
16th to endDay
42%414%19%15%2
1723
March1st to 15thDay
38%5%10%22%17%6%
2145
16th to endDay
46%6%11%20%13%2
2174
April1st to 15thDay
33%6%14%24%15%5%
2031
16th to endDay
44%6%12%16%15%4
2287
May1st to 15thDay
45%11%14%16%9%1
2331
16th to endDay
43%10%14%20%7%2
2435
June1st to 15thDay
45%12%16%15%9%
2340
16th to endDay
41%12%14%17%12%1
2340
July1st to 15thDay
49%11%14%12%8%2
2201
16th to endDay
47%12%18%12%7%1
2310
August1st to 15thDay
53%12%13%13%6%
2327
16th to endDay
49%10%14%16%6%1
2399
September1st to 15thDay
45%8%11%17%14%2
1999
16th to endDay
50%6%10%15%16%1
1980
October1st to 15thDay
37%5%10%22%17%5%
1848
16th to endDay
34%37%25%20%8%
1920
November1st to 15thDay
32%5%10%18%25%7%
1832
16th to endDay
36%49%19%25%4
1755
December1st to 15thDay
41%6%9%20%17%5%
1755
16th to endDay
45%412%17%15%3
1872
January1st to 15thNight
36%6%11%18%20%7%
2522
16th to endNight
37%5%10%22%19%4
2704
February1st to 15thNight
38%5%9%24%17%4
2447
16th to endNight
38%7%14%23%14%2
2036
March1st to 15thNight
39%5%11%22%16%5%
2145
16th to endNight
42%5%13%21%14%2
2178
April1st to 15thNight
35%6%13%24%15%5%
1916
16th to endNight
39%7%13%18%16%5%
1683
May1st to 15thNight
43%8%14%20%12%
1620
16th to endNight
37%10%20%21%7%2
1684
June1st to 15thNight
34%12%19%22%9%1
1620
16th to endNight
32%10%19%20%13%3
1620
July1st to 15thNight
36%12%16%20%11%2
1530
16th to endNight
31%12%23%21%9%1
1595
August1st to 15thNight
42%10%16%17%12%
1609
16th to endNight
39%10%16%22%9%1
1791
September1st to 15thNight
39%8%15%16%16%3
1958
16th to endNight
44%6%11%16%19%1
1980
October1st to 15thNight
36%5%10%22%20%3
2112
16th to endNight
30%37%25%23%8%
2304
November1st to 15thNight
33%49%19%23%9%
2353
16th to endNight
33%47%22%26%5%
2535
December1st to 15thNight
40%6%10%20%17%6%
2535
16th to endNight
46%5%12%16%16%2
2704

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
28%25%29%12%2
135
16th to endDay
25%31%31%9%2
144
February1st to 15thDay
29%33%28%7%
135
16th to endDay
30%24%33%9%1
133
March1st to 15thDay
22%25%26%17%7%
330
16th to endDay
21%22%26%18%8%1
311
April1st to 15thDay
18%19%21%24%12%2
270
16th to endDay
20%9%24%20%18%7%
270
May1st to 15thDay
20%16%27%18%10%6%
288
16th to endDay
18%5%20%23%17%14%
331
June1st to 15thDay
13%5%18%23%23%15%
315
16th to endDay
13%323%29%17%13%
315
July1st to 15thDay
15%219%23%22%16%
305
16th to endDay
11%110%26%28%20%
326
August1st to 15thDay
21%115%21%20%20%
313
16th to endDay
13%18%25%24%26%
332
September1st to 15thDay
19%310%17%30%19%
315
16th to endDay
21%5%14%23%21%13%
314
October1st to 15thDay
23%418%23%21%7%
315
16th to endDay
18%10%22%24%17%6%
336
November1st to 15thDay
24%10%23%24%12%4
250
16th to endDay
13%23%20%31%8%2
135
December1st to 15thDay
22%22%35%13%5%
135
16th to endDay
36%16%35%11%
144
January1st to 15thNight
19%20%31%22%6%
780
16th to endNight
18%20%35%21%3
832
February1st to 15thNight
19%21%31%25%1
764
16th to endNight
17%23%37%19%2
683
March1st to 15thNight
19%20%30%25%4
780
16th to endNight
20%13%32%23%8%
792
April1st to 15thNight
16%20%26%25%10%
718
16th to endNight
21%10%23%30%13%1
603
May1st to 15thNight
20%7%26%30%15%1
540
16th to endNight
15%414%30%28%7%
563
June1st to 15thNight
10%115%32%34%5%
540
16th to endNight
9%112%32%38%5%
540
July1st to 15thNight
14%18%28%41%5%
510
16th to endNight
418%26%47%11%
564
August1st to 15thNight
17%8%32%34%6%
539
16th to endNight
13%6%26%43%8%
645
September1st to 15thNight
14%212%26%36%7%
720
16th to endNight
23%212%25%31%4
717
October1st to 15thNight
19%7%18%25%22%6%
720
16th to endNight
15%11%23%29%17%2
768
November1st to 15thNight
17%10%21%31%15%3
760
16th to endNight
17%15%23%30%12%1
780
December1st to 15thNight
20%15%27%27%8%
780
16th to endNight
26%16%27%24%5%
832
Page generated at 2018-03-22 11:34:19. Version ac04

Copyright 2018 A. Danko


Doughton Park Clear Sky Chart |Charts Home