Bonnechere Provincial Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Bonnechere Provincial Park clear sky chart from 2005-11-05 to 2017-09-18.

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
28%
14645
12%
46884
7%
14616
34%
14616
15%
33889

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
14%
720
6%
2506
2%
716
19%
716
5%
2080
January16th to endNight
21%
768
11%
2589
6%
768
28%
768
11%
1992
February1st to 15thNight
16%
701
9%
2287
3%
701
22%
701
9%
1810
February16th to endNight
19%
631
12%
2002
5%
631
29%
631
12%
1491
March1st to 15thNight
17%
720
12%
2040
6%
720
24%
720
13%
1560
March16th to endNight
29%
768
19%
2077
8%
768
37%
768
21%
1431
April1st to 15thNight
22%
718
15%
1796
4%
718
28%
718
19%
1347
April16th to endNight
31%
606
17%
1686
8%
606
36%
606
21%
1190
May1st to 15thNight
33%
378
16%
1458
15%
378
41%
378
16%
967
May16th to endNight
31%
375
13%
1497
8%
374
44%
374
18%
948
June1st to 15thNight
31%
360
9%
1440
6%
360
41%
360
17%
930
June16th to endNight
39%
360
10%
1440
10%
360
45%
360
18%
916
July1st to 15thNight
45%
340
15%
1360
17%
340
54%
340
26%
751
July16th to endNight
48%
376
14%
1418
13%
354
56%
354
25%
808
August1st to 15thNight
51%
506
14%
1577
9%
504
56%
504
26%
982
August16th to endNight
48%
657
20%
1803
10%
657
55%
657
34%
1110
September1st to 15thNight
41%
720
15%
1800
7%
720
44%
720
28%
1247
September16th to endNight
44%
669
19%
1847
13%
669
48%
669
30%
1203
October1st to 15thNight
30%
660
16%
1980
11%
660
38%
660
18%
1416
October16th to endNight
21%
704
10%
2156
5%
704
28%
704
11%
1692
November1st to 15thNight
26%
700
15%
2397
11%
700
33%
700
13%
1725
November16th to endNight
20%
720
9%
2520
6%
720
24%
720
9%
1984
December1st to 15thNight
15%
720
6%
2520
2%
720
19%
720
7%
2080
December16th to endNight
14%
768
7%
2688
3%
768
19%
768
7%
2229

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
17%9%47%6%34446%31%
47920
Night
16%10%47%6%34446%31%
47054
TransparencyDay
53%5%10%18%9%1
47608
Night
53%5%11%18%9%
46884
SeeingDay
23%12%30%20%10%3
5375
Night
22%13%30%24%9%
14648

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
19%13%6%10%8%3443421%
1432
16th to endDay
11%15%6%10%9%5%5%44422%
1634
February1st to 15thDay
9%15%7%13%10%35%45%5%20%
1575
16th to endDay
17%14%6%8%5%445%5%5%23%
1470
March1st to 15thDay
15%13%5%9%7%3444425%
1909
16th to endDay
13%9%46%6%24436%38%
2145
April1st to 15thDay
22%11%45%5%2333432%
2152
16th to endDay
21%7%25%423345%38%
2283
May1st to 15thDay
19%10%35%5%2345%6%33%
2493
16th to endDay
15%8%36%5%345%5%6%34%
2618
June1st to 15thDay
21%7%37%5%34447%30%
2520
16th to endDay
16%6%35%6%45%5%5%8%33%
2520
July1st to 15thDay
13%5%35%5%45%5%6%7%37%
2520
16th to endDay
11%5%26%5%36%6%7%9%33%
2654
August1st to 15thDay
12%6%37%7%45%45%7%34%
2371
16th to endDay
12%5%26%6%45%5%6%7%36%
2387
September1st to 15thDay
18%5%35%5%23347%38%
2160
16th to endDay
18%5%25%424436%41%
1837
October1st to 15thDay
22%8%36%5%33445%32%
1650
16th to endDay
26%11%49%5%3443422%
1716
November1st to 15thDay
15%10%37%6%3335%5%33%
1458
16th to endDay
22%14%6%8%7%24345%19%
1440
December1st to 15thDay
17%19%7%11%7%45%33414%
1440
16th to endDay
22%17%7%8%5%23335%18%
1536
January1st to 15thNight
16%15%6%11%10%46%44415%
2506
16th to endNight
11%14%5%10%8%45%446%24%
2589
February1st to 15thNight
10%14%7%11%9%5%5%445%21%
2285
16th to endNight
14%13%5%10%6%35%445%26%
2002
March1st to 15thNight
15%12%6%7%8%34335%28%
2028
16th to endNight
12%9%47%5%23345%40%
2077
April1st to 15thNight
20%11%35%42334434%
1796
16th to endNight
17%9%26%434436%36%
1686
May1st to 15thNight
20%7%35%434347%36%
1458
16th to endNight
13%5%25%6%45%45%6%38%
1495
June1st to 15thNight
17%7%35%425%35%7%37%
1440
16th to endNight
14%6%25%5%36%6%5%7%36%
1440
July1st to 15thNight
9%3244345%5%6%49%
1440
16th to endNight
9%424435%5%6%9%45%
1514
August1st to 15thNight
9%425%5%35%5%6%8%43%
1587
16th to endNight
9%415%5%2435%8%49%
1803
September1st to 15thNight
14%5%25%4235%46%44%
1800
16th to endNight
16%7%23323346%46%
1847
October1st to 15thNight
21%8%36%423335%37%
1980
16th to endNight
24%11%36%6%3345%6%23%
2156
November1st to 15thNight
16%10%36%7%2446%5%31%
2397
16th to endNight
22%13%5%7%7%33335%23%
2520
December1st to 15thNight
18%18%6%9%6%3433418%
2520
16th to endNight
22%18%6%10%5%3442417%
2688

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
67%48%11%6%
1433
16th to endDay
64%5%7%13%6%1
1634
February1st to 15thDay
65%5%10%13%4
1577
16th to endDay
61%49%13%10%
1470
March1st to 15thDay
61%410%15%7%1
1920
16th to endDay
47%49%19%15%4
2145
April1st to 15thDay
55%37%17%11%3
2152
16th to endDay
49%37%20%16%2
2283
May1st to 15thDay
51%49%17%12%2
2493
16th to endDay
48%6%10%20%12%2
2622
June1st to 15thDay
53%6%10%19%10%
2520
16th to endDay
47%7%11%20%12%1
2520
July1st to 15thDay
41%7%11%25%12%1
2371
16th to endDay
43%8%15%22%9%
2487
August1st to 15thDay
47%7%14%19%10%
2357
16th to endDay
43%8%14%24%8%
2387
September1st to 15thDay
45%5%13%24%10%
2160
16th to endDay
44%5%10%29%8%
1837
October1st to 15thDay
54%5%12%17%10%
1650
16th to endDay
65%6%10%12%4
1716
November1st to 15thDay
52%5%15%18%8%
1458
16th to endDay
67%410%11%41
1440
December1st to 15thDay
74%48%8%3
1440
16th to endDay
69%49%11%4
1536
January1st to 15thNight
70%6%9%8%4
2506
16th to endNight
61%5%10%14%7%
2589
February1st to 15thNight
64%5%10%14%4
2287
16th to endNight
58%410%17%8%
2002
March1st to 15thNight
59%310%17%7%
2040
16th to endNight
47%310%19%16%2
2077
April1st to 15thNight
53%47%19%13%2
1796
16th to endNight
48%48%21%14%2
1686
May1st to 15thNight
49%47%18%17%2
1458
16th to endNight
42%7%12%20%13%2
1497
June1st to 15thNight
46%6%13%21%11%
1440
16th to endNight
43%7%12%22%13%
1440
July1st to 15thNight
32%7%13%28%17%
1360
16th to endNight
34%7%15%29%12%
1418
August1st to 15thNight
36%9%16%25%11%
1577
16th to endNight
32%7%17%32%9%
1803
September1st to 15thNight
41%7%13%25%11%
1800
16th to endNight
39%5%13%33%7%
1847
October1st to 15thNight
50%6%9%21%11%
1980
16th to endNight
60%6%11%15%5%
2156
November1st to 15thNight
53%6%12%17%9%
2397
16th to endNight
64%5%11%14%2
2520
December1st to 15thNight
69%6%10%11%2
2520
16th to endNight
71%49%9%5%
2688

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
30%20%31%15%3
60
16th to endDay
35%9%35%14%3
81
February1st to 15thDay
27%27%37%5%1
90
16th to endDay
38%16%28%13%3
129
March1st to 15thDay
27%17%31%18%4
270
16th to endDay
23%16%27%20%10%1
288
April1st to 15thDay
24%22%30%14%6%1
270
16th to endDay
26%15%28%14%9%5%
270
May1st to 15thDay
31%9%25%19%9%4
288
16th to endDay
21%14%35%18%8%2
331
June1st to 15thDay
27%10%29%22%10%
315
16th to endDay
16%10%33%25%11%2
315
July1st to 15thDay
13%7%35%30%10%3
305
16th to endDay
11%7%31%29%16%3
326
August1st to 15thDay
16%428%28%16%6%
313
16th to endDay
15%428%26%14%9%
332
September1st to 15thDay
20%7%26%18%15%12%
315
16th to endDay
20%7%25%21%17%6%
262
October1st to 15thDay
23%15%26%20%11%1
255
16th to endDay
35%12%30%15%6%
264
November1st to 15thDay
17%15%34%22%8%
112
16th to endDay
36%15%30%13%5%
60
December1st to 15thDay
21%20%38%13%6%
60
16th to endDay
45%25%23%41
64
January1st to 15thNight
24%17%33%18%5%
720
16th to endNight
21%13%34%22%7%
768
February1st to 15thNight
18%17%39%18%5%
704
16th to endNight
22%17%33%22%3
631
March1st to 15thNight
27%17%30%20%3
720
16th to endNight
18%16%30%22%10%1
768
April1st to 15thNight
26%15%30%22%4
718
16th to endNight
22%14%28%23%10%
606
May1st to 15thNight
24%8%28%28%8%1
378
16th to endNight
17%10%35%25%10%
375
June1st to 15thNight
21%7%34%28%7%
360
16th to endNight
18%7%27%34%11%
360
July1st to 15thNight
11%432%35%12%2
340
16th to endNight
9%5%31%37%16%
376
August1st to 15thNight
11%225%36%21%2
506
16th to endNight
11%429%33%18%2
657
September1st to 15thNight
19%5%29%24%17%3
720
16th to endNight
19%5%25%27%19%2
669
October1st to 15thNight
26%12%25%23%11%
660
16th to endNight
30%15%26%20%6%
704
November1st to 15thNight
22%17%27%21%10%1
700
16th to endNight
30%17%25%20%5%
720
December1st to 15thNight
28%19%29%18%3
720
16th to endNight
33%14%28%18%3
768
Page generated at 2017-09-19 07:32:26. Version ac04

Copyright 2017 A. Danko


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