Belleplain State Forest
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Belleplain State Forest clear sky chart from 2005-11-05 to 2018-02-22.

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
36%
15813
20%
48896
11%
15779
47%
15779
23%
31057

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
22%
780
21%
2716
8%
776
39%
776
17%
1678
January16th to endNight
18%
832
22%
2730
7%
832
37%
832
19%
1693
February1st to 15thNight
18%
764
18%
2418
6%
761
33%
761
18%
1529
February16th to endNight
20%
659
25%
1976
8%
659
42%
659
20%
1239
March1st to 15thNight
24%
720
20%
2112
9%
720
38%
720
24%
1331
March16th to endNight
25%
768
21%
2017
9%
768
35%
768
24%
1371
April1st to 15thNight
26%
718
18%
1796
5%
718
34%
718
27%
1195
April16th to endNight
38%
720
17%
1800
7%
720
41%
720
27%
1241
May1st to 15thNight
33%
556
16%
1636
8%
556
39%
556
21%
1136
May16th to endNight
49%
374
14%
1497
13%
374
54%
374
18%
962
June1st to 15thNight
50%
360
15%
1440
16%
360
55%
360
21%
897
June16th to endNight
61%
360
16%
1440
20%
360
66%
360
24%
845
July1st to 15thNight
62%
340
12%
1360
15%
340
63%
340
19%
858
July16th to endNight
66%
407
15%
1447
15%
383
70%
383
25%
843
August1st to 15thNight
65%
614
16%
1684
12%
611
66%
611
32%
1089
August16th to endNight
61%
764
19%
1910
10%
764
63%
764
33%
1269
September1st to 15thNight
56%
720
24%
1800
14%
720
60%
720
33%
1196
September16th to endNight
52%
717
22%
1951
17%
717
56%
717
30%
1252
October1st to 15thNight
46%
720
21%
2133
17%
720
53%
720
27%
1346
October16th to endNight
37%
768
27%
2348
17%
768
52%
768
27%
1392
November1st to 15thNight
33%
760
21%
2472
12%
760
46%
760
23%
1508
November16th to endNight
30%
780
22%
2571
12%
780
44%
780
20%
1605
December1st to 15thNight
24%
780
17%
2730
6%
780
36%
780
15%
1779
December16th to endNight
20%
832
21%
2912
7%
832
38%
832
18%
1803

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
13%5%2442445%8%42%
49349
Night
14%5%2442445%7%43%
49069
Cloud CoverDay
13%5%2442445%8%43%
49358
Night
14%5%25%42445%7%43%
49075
TransparencyDay
38%6%12%23%15%2
49040
Night
40%6%11%22%16%2
48896
SeeingDay
17%9%26%27%14%3
6293
Night
17%11%28%27%13%1
15814

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
13%6%25%32436%6%44%
1552
16th to endDay
16%6%24323445%45%
1843
February1st to 15thDay
15%7%25%425%35%6%42%
1771
16th to endDay
12%8%36%43425%5%41%
1644
March1st to 15thDay
16%5%24424346%44%
1835
16th to endDay
16%7%2432435%5%43%
2206
April1st to 15thDay
16%5%33324446%45%
2152
16th to endDay
13%5%2442445%8%43%
2160
May1st to 15thDay
15%6%234245%5%9%38%
2323
16th to endDay
12%5%244245%5%9%43%
2618
June1st to 15thDay
11%5%25%425%6%6%9%39%
2520
16th to endDay
10%4144346%6%11%42%
2520
July1st to 15thDay
8%5%245%345%7%10%41%
2520
16th to endDay
7%425%6%36%7%7%11%37%
2620
August1st to 15thDay
10%5%25%4345%5%9%43%
2251
16th to endDay
10%414425%5%7%9%42%
2292
September1st to 15thDay
12%425%43346%8%45%
2160
16th to endDay
13%6%35%5%2346%7%40%
2007
October1st to 15thDay
15%5%2443435%6%44%
1824
16th to endDay
15%415%423235%50%
1875
November1st to 15thDay
17%6%2442335%6%43%
1716
16th to endDay
14%424324446%48%
1716
December1st to 15thDay
15%6%25%5%25%437%41%
1560
16th to endDay
19%7%24323346%41%
1664
January1st to 15thNight
16%5%24424446%43%
2716
16th to endNight
16%6%24423446%43%
2730
February1st to 15thNight
15%6%25%433445%43%
2417
16th to endNight
15%5%2442435%5%46%
1976
March1st to 15thNight
16%6%23413337%47%
2099
16th to endNight
17%7%34424335%42%
2017
April1st to 15thNight
15%6%25%324446%43%
1796
16th to endNight
17%5%25%43445%7%41%
1800
May1st to 15thNight
15%8%36%5%35%45%6%36%
1636
16th to endNight
14%6%35%5%36%447%37%
1495
June1st to 15thNight
13%5%35%435%45%8%41%
1440
16th to endNight
8%425%5%345%6%10%42%
1440
July1st to 15thNight
7%426%6%37%6%6%7%39%
1440
16th to endNight
6%426%5%36%6%6%10%40%
1545
August1st to 15thNight
7%4246%35%5%6%8%44%
1695
16th to endNight
10%425%4245%6%8%45%
1910
September1st to 15thNight
12%5%24423447%46%
1800
16th to endNight
14%6%243245%5%7%44%
1951
October1st to 15thNight
16%5%24423346%45%
2133
16th to endNight
14%5%24323346%51%
2348
November1st to 15thNight
14%6%24323346%48%
2472
16th to endNight
13%425%5%345%47%43%
2571
December1st to 15thNight
17%7%26%5%2445%6%38%
2730
16th to endNight
17%5%2442445%6%42%
2912

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
13%6%25%32445%6%45%
1552
16th to endDay
16%6%24413445%45%
1843
February1st to 15thDay
15%7%25%42435%6%42%
1771
16th to endDay
12%8%36%5%34345%41%
1644
March1st to 15thDay
16%424424446%43%
1845
16th to endDay
16%7%2442435%6%42%
2205
April1st to 15thDay
15%5%24324446%45%
2152
16th to endDay
13%5%244245%6%8%43%
2160
May1st to 15thDay
15%6%244345%5%8%39%
2323
16th to endDay
12%5%245%3445%8%43%
2618
June1st to 15thDay
11%5%25%425%5%6%10%39%
2520
16th to endDay
10%423335%6%6%11%43%
2520
July1st to 15thDay
8%5%244345%7%10%41%
2520
16th to endDay
7%4246%36%7%7%11%37%
2620
August1st to 15thDay
10%5%15%5%345%5%9%44%
2251
16th to endDay
10%424425%6%7%9%42%
2292
September1st to 15thDay
12%42442345%8%45%
2160
16th to endDay
13%7%25%43445%7%39%
2007
October1st to 15thDay
15%5%2442435%6%44%
1824
16th to endDay
15%424423235%50%
1875
November1st to 15thDay
17%6%24423346%43%
1716
16th to endDay
14%324423447%48%
1716
December1st to 15thDay
15%6%25%425%437%40%
1560
16th to endDay
19%7%14322346%41%
1664
January1st to 15thNight
16%5%2442445%6%43%
2716
16th to endNight
16%6%24423446%43%
2730
February1st to 15thNight
15%6%25%5%23445%43%
2410
16th to endNight
15%5%1432345%5%46%
1976
March1st to 15thNight
16%6%23423337%46%
2112
16th to endNight
17%7%35%42334442%
2017
April1st to 15thNight
15%6%34423437%43%
1796
16th to endNight
17%5%15%42435%6%41%
1800
May1st to 15thNight
16%8%26%44445%6%35%
1636
16th to endNight
15%6%26%5%45%45%7%37%
1495
June1st to 15thNight
13%5%34425%45%8%40%
1440
16th to endNight
8%425%5%45%6%5%11%41%
1440
July1st to 15thNight
7%426%7%36%6%7%7%39%
1440
16th to endNight
6%5%25%5%36%5%7%10%40%
1545
August1st to 15thNight
7%4245%45%5%6%8%44%
1695
16th to endNight
10%5%244246%5%8%45%
1910
September1st to 15thNight
13%4244235%48%45%
1800
16th to endNight
14%6%2342345%7%43%
1951
October1st to 15thNight
16%5%24423346%45%
2133
16th to endNight
14%424323346%51%
2348
November1st to 15thNight
14%6%24323345%48%
2472
16th to endNight
13%435%5%3345%7%43%
2571
December1st to 15thNight
17%6%35%5%24446%38%
2730
16th to endNight
17%5%2442445%6%42%
2912

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
38%5%16%21%13%4
1553
16th to endDay
40%410%24%16%3
1843
February1st to 15thDay
42%413%24%12%2
1774
16th to endDay
42%410%26%12%2
1644
March1st to 15thDay
40%5%12%24%15%2
1845
16th to endDay
41%6%9%22%17%3
2206
April1st to 15thDay
38%5%10%23%16%4
2152
16th to endDay
37%7%11%16%21%4
2160
May1st to 15thDay
40%6%14%21%14%1
2323
16th to endDay
37%8%14%25%12%1
2622
June1st to 15thDay
36%12%13%24%11%1
2520
16th to endDay
32%10%15%23%16%1
2520
July1st to 15thDay
34%8%14%25%15%2
2371
16th to endDay
34%10%14%24%14%1
2455
August1st to 15thDay
35%7%12%26%16%1
2238
16th to endDay
32%8%15%22%17%3
2292
September1st to 15thDay
34%7%12%23%19%2
2160
16th to endDay
41%6%10%17%21%1
2007
October1st to 15thDay
39%5%12%24%15%2
1824
16th to endDay
37%39%27%20%1
1875
November1st to 15thDay
41%412%23%15%2
1716
16th to endDay
36%5%10%27%16%3
1716
December1st to 15thDay
43%5%16%20%12%2
1560
16th to endDay
43%413%25%11%1
1664
January1st to 15thNight
41%5%11%21%17%3
2716
16th to endNight
40%411%25%15%1
2730
February1st to 15thNight
42%412%24%14%2
2418
16th to endNight
39%5%9%23%19%3
1976
March1st to 15thNight
39%412%23%16%3
2112
16th to endNight
44%410%19%17%3
2017
April1st to 15thNight
40%5%10%21%17%4
1796
16th to endNight
42%5%9%16%22%4
1800
May1st to 15thNight
47%6%8%20%14%2
1636
16th to endNight
44%7%13%18%13%1
1497
June1st to 15thNight
41%7%12%21%16%
1440
16th to endNight
35%8%12%27%13%2
1440
July1st to 15thNight
40%10%15%19%12%2
1360
16th to endNight
33%9%17%23%14%1
1447
August1st to 15thNight
34%9%15%22%17%1
1684
16th to endNight
34%9%12%21%20%2
1910
September1st to 15thNight
36%7%11%23%18%2
1800
16th to endNight
38%5%11%20%21%2
1951
October1st to 15thNight
39%412%23%17%2
2133
16th to endNight
35%410%28%18%3
2348
November1st to 15thNight
39%411%21%17%5%
2472
16th to endNight
39%6%10%22%17%3
2571
December1st to 15thNight
46%6%12%21%11%2
2730
16th to endNight
41%5%14%23%13%2
2912

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
13%26%37%14%6%1
90
16th to endDay
24%16%32%25%
137
February1st to 15thDay
25%23%37%12%1
197
16th to endDay
15%21%42%17%2
265
March1st to 15thDay
19%21%28%25%5%
270
16th to endDay
18%15%37%22%32
288
April1st to 15thDay
20%12%35%22%7%1
270
16th to endDay
22%7%28%29%10%1
270
May1st to 15thDay
29%10%30%18%9%1
288
16th to endDay
16%5%20%34%18%4
331
June1st to 15thDay
15%427%31%17%3
315
16th to endDay
14%126%37%18%1
315
July1st to 15thDay
12%119%40%20%4
305
16th to endDay
7%315%38%28%5%
326
August1st to 15thDay
13%116%35%26%6%
313
16th to endDay
10%13%36%27%11%
332
September1st to 15thDay
13%324%26%20%11%
315
16th to endDay
20%421%30%14%8%
314
October1st to 15thDay
21%320%28%19%6%
315
16th to endDay
15%14%28%22%16%2
325
November1st to 15thDay
20%10%30%25%13%1
280
16th to endDay
15%21%30%18%12%1
246
December1st to 15thDay
20%21%28%18%11%
90
16th to endDay
30%22%30%16%
96
January1st to 15thNight
19%22%31%21%5%
780
16th to endNight
20%21%37%19%1
832
February1st to 15thNight
19%19%38%21%1
764
16th to endNight
18%21%35%20%2
659
March1st to 15thNight
20%16%34%22%5%
720
16th to endNight
21%12%34%22%7%1
768
April1st to 15thNight
18%12%38%23%5%
718
16th to endNight
20%6%30%32%9%
720
May1st to 15thNight
20%7%33%29%9%
556
16th to endNight
17%219%37%20%1
375
June1st to 15thNight
16%222%36%20%1
360
16th to endNight
8%120%46%22%1
360
July1st to 15thNight
8%116%48%23%2
340
16th to endNight
8%112%44%30%2
407
August1st to 15thNight
9%113%45%26%2
614
16th to endNight
13%114%36%31%4
764
September1st to 15thNight
15%119%33%25%4
720
16th to endNight
18%219%29%26%3
717
October1st to 15thNight
20%6%22%29%17%3
720
16th to endNight
17%13%29%23%15%
768
November1st to 15thNight
18%14%29%23%11%1
760
16th to endNight
16%18%30%22%10%
780
December1st to 15thNight
21%18%30%17%10%1
780
16th to endNight
18%20%37%21%2
832
Page generated at 2018-02-23 11:21:32. Version ac04

Copyright 2018 A. Danko


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