Rondeau Provincial Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Rondeau Provincial 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
35%
15875
14%
48993
10%
15837
40%
15837
17%
34598

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
13%
850
9%
2594
4%
848
19%
848
8%
2120
January16th to endNight
17%
832
8%
2704
3%
832
23%
832
8%
2156
February1st to 15thNight
17%
761
8%
2482
3%
761
24%
761
10%
1933
February16th to endNight
25%
683
11%
2078
5%
683
32%
683
12%
1584
March1st to 15thNight
27%
780
14%
2197
8%
780
31%
780
15%
1626
March16th to endNight
33%
792
19%
2178
11%
792
39%
792
20%
1520
April1st to 15thNight
34%
662
14%
1837
8%
662
39%
662
20%
1312
April16th to endNight
39%
540
20%
1620
9%
540
47%
540
21%
1053
May1st to 15thNight
39%
540
14%
1620
9%
540
45%
540
18%
1141
May16th to endNight
50%
498
16%
1621
13%
498
55%
498
22%
1012
June1st to 15thNight
50%
360
16%
1389
16%
360
59%
360
21%
802
June16th to endNight
54%
360
19%
1260
18%
360
63%
360
24%
734
July1st to 15thNight
63%
464
17%
1336
16%
464
65%
464
34%
780
July16th to endNight
57%
564
16%
1595
12%
531
65%
531
33%
922
August1st to 15thNight
64%
539
19%
1609
15%
536
67%
536
32%
936
August16th to endNight
62%
573
25%
1719
18%
573
67%
573
33%
1003
September1st to 15thNight
56%
717
21%
1923
15%
717
59%
717
30%
1248
September16th to endNight
54%
717
23%
1980
17%
717
58%
717
30%
1246
October1st to 15thNight
45%
720
18%
2115
16%
720
49%
720
22%
1402
October16th to endNight
26%
768
14%
2336
8%
768
35%
768
15%
1701
November1st to 15thNight
34%
760
17%
2471
15%
760
38%
760
17%
1680
November16th to endNight
19%
780
11%
2707
6%
780
27%
780
10%
2022
December1st to 15thNight
15%
780
6%
2730
3%
780
19%
780
7%
2209
December16th to endNight
12%
835
5%
2892
1%
835
17%
835
5%
2456

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%7%36%5%35%5%5%7%34%
49808
Night
15%8%36%5%3445%6%34%
49178
Cloud CoverDay
14%7%36%5%35%5%5%7%35%
49818
Night
15%8%36%5%3445%6%34%
49182
TransparencyDay
46%8%14%19%10%1
49511
Night
49%7%12%18%11%1
48993
SeeingDay
15%11%19%28%19%5%
6227
Night
17%19%20%24%14%2
15883

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%12%5%9%8%36%446%18%
1661
16th to endDay
16%15%6%9%8%36%5%5%417%
1872
February1st to 15thDay
17%12%6%8%8%35%445%22%
1710
16th to endDay
15%10%5%8%7%35%5%5%6%25%
1679
March1st to 15thDay
18%9%5%7%6%45%445%27%
2082
16th to endDay
16%7%47%5%345%47%30%
2174
April1st to 15thDay
17%7%46%5%35%5%5%7%31%
2119
16th to endDay
16%6%25%5%2445%7%38%
2340
May1st to 15thDay
14%7%36%5%35%45%8%36%
2331
16th to endDay
10%425%425%46%8%43%
2491
June1st to 15thDay
9%5%25%5%25%5%6%8%41%
2567
16th to endDay
9%325%5%35%5%8%10%40%
2700
July1st to 15thDay
7%42442446%10%47%
2535
16th to endDay
7%424435%5%7%10%45%
2465
August1st to 15thDay
5%425%5%35%6%8%10%42%
2340
16th to endDay
9%4135%345%6%9%46%
2474
September1st to 15thDay
10%5%245%3446%7%44%
2033
16th to endDay
14%4145%3445%8%43%
1980
October1st to 15thDay
15%5%26%6%36%35%5%38%
1844
16th to endDay
22%7%36%434446%32%
1887
November1st to 15thDay
14%8%45%5%45%45%7%35%
1717
16th to endDay
18%13%5%8%5%25%5%46%23%
1581
December1st to 15thDay
19%16%5%8%6%3446%5%18%
1560
16th to endDay
22%14%7%11%7%35%445%13%
1666
January1st to 15thNight
22%12%5%8%5%2435%5%22%
2594
16th to endNight
16%15%6%9%6%45%5%45%20%
2704
February1st to 15thNight
17%13%5%10%6%25%445%24%
2480
16th to endNight
18%10%48%6%45%5%5%5%25%
2078
March1st to 15thNight
17%11%36%5%4445%7%29%
2185
16th to endNight
16%7%35%5%2445%6%36%
2178
April1st to 15thNight
17%8%46%5%34446%35%
1837
16th to endNight
12%6%25%5%35%5%5%7%40%
1620
May1st to 15thNight
15%5%36%5%35%5%7%7%32%
1620
16th to endNight
11%5%25%43445%6%45%
1619
June1st to 15thNight
9%4245%346%7%8%43%
1389
16th to endNight
8%4245%35%47%8%46%
1260
July1st to 15thNight
6%324433447%55%
1418
16th to endNight
5%3145%2445%10%51%
1703
August1st to 15thNight
5%314435%5%7%9%49%
1620
16th to endNight
9%42442435%7%51%
1719
September1st to 15thNight
10%4345%34446%47%
1923
16th to endNight
12%5%25%43345%7%45%
1980
October1st to 15thNight
16%5%35%434446%41%
2115
16th to endNight
19%7%36%6%34447%31%
2336
November1st to 15thNight
15%6%36%5%35%45%6%36%
2471
16th to endNight
22%10%46%43445%7%26%
2707
December1st to 15thNight
22%13%5%8%5%35%446%20%
2730
16th to endNight
21%14%6%10%7%35%44416%
2892

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
19%12%5%9%7%45%446%18%
1661
16th to endDay
16%14%6%9%8%36%44418%
1872
February1st to 15thDay
17%13%6%8%7%45%44422%
1710
16th to endDay
15%10%48%7%36%5%46%25%
1679
March1st to 15thDay
18%9%48%6%445%45%28%
2093
16th to endDay
17%7%47%5%3446%7%30%
2173
April1st to 15thDay
18%7%45%5%35%45%7%31%
2119
16th to endDay
16%6%25%5%2446%6%38%
2340
May1st to 15thDay
15%7%26%5%35%45%7%36%
2331
16th to endDay
10%425%5%345%5%8%44%
2491
June1st to 15thDay
9%5%25%5%25%5%6%9%42%
2567
16th to endDay
9%325%5%35%6%7%10%41%
2700
July1st to 15thDay
8%31442446%9%49%
2535
16th to endDay
7%323435%5%7%10%45%
2465
August1st to 15thDay
5%425%5%35%6%8%11%42%
2340
16th to endDay
9%4144345%5%9%47%
2474
September1st to 15thDay
11%5%245%35%45%8%44%
2033
16th to endDay
14%423435%45%7%43%
1980
October1st to 15thDay
15%5%26%6%45%445%39%
1844
16th to endDay
22%7%36%42445%6%32%
1887
November1st to 15thDay
15%8%35%5%35%46%6%35%
1717
16th to endDay
19%13%5%7%5%245%46%23%
1581
December1st to 15thDay
20%15%5%8%6%345%47%18%
1560
16th to endDay
22%14%7%10%7%36%45%5%13%
1666
January1st to 15thNight
23%12%6%8%6%34345%22%
2594
16th to endNight
16%15%7%9%7%345%45%20%
2704
February1st to 15thNight
17%13%5%10%7%25%445%24%
2473
16th to endNight
19%9%47%6%45%5%5%5%26%
2078
March1st to 15thNight
18%10%35%5%3445%7%29%
2197
16th to endNight
16%8%35%5%2445%7%37%
2178
April1st to 15thNight
17%8%35%5%34446%35%
1837
16th to endNight
12%5%25%5%35%5%5%7%40%
1620
May1st to 15thNight
15%5%36%5%45%5%6%7%32%
1619
16th to endNight
11%5%25%425%447%45%
1619
June1st to 15thNight
10%4245%345%6%8%44%
1389
16th to endNight
9%5%144345%6%8%46%
1260
July1st to 15thNight
6%414423446%55%
1418
16th to endNight
6%3145%335%5%9%51%
1703
August1st to 15thNight
5%315%425%5%7%9%50%
1620
16th to endNight
9%424333448%51%
1719
September1st to 15thNight
11%5%34424446%47%
1923
16th to endNight
12%4245%2345%7%46%
1980
October1st to 15thNight
16%5%25%424446%41%
2115
16th to endNight
20%6%36%6%3345%7%32%
2336
November1st to 15thNight
15%7%35%5%345%5%6%37%
2471
16th to endNight
22%10%36%5%3445%6%27%
2707
December1st to 15thNight
22%12%5%8%6%25%446%21%
2730
16th to endNight
22%13%6%10%6%35%44416%
2892

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
68%7%9%10%3
1662
16th to endDay
67%7%13%8%3
1872
February1st to 15thDay
63%6%10%13%4
1712
16th to endDay
58%7%11%16%5%1
1679
March1st to 15thDay
57%8%10%14%7%
2093
16th to endDay
50%6%13%19%8%1
2174
April1st to 15thDay
49%8%12%18%11%
2119
16th to endDay
45%5%13%19%13%2
2340
May1st to 15thDay
45%7%13%21%10%1
2331
16th to endDay
36%8%15%23%13%1
2495
June1st to 15thDay
37%9%14%23%13%1
2567
16th to endDay
35%8%17%20%16%1
2700
July1st to 15thDay
29%8%13%28%18%2
2388
16th to endDay
33%8%18%24%13%2
2310
August1st to 15thDay
32%10%18%24%13%
2327
16th to endDay
32%7%17%27%12%2
2474
September1st to 15thDay
37%8%15%26%11%
2033
16th to endDay
38%7%14%24%13%
1980
October1st to 15thDay
45%7%12%19%13%1
1844
16th to endDay
52%7%16%16%7%
1887
November1st to 15thDay
47%10%12%17%9%1
1717
16th to endDay
61%8%13%12%4
1581
December1st to 15thDay
65%8%13%8%3
1560
16th to endDay
73%7%9%7%1
1666
January1st to 15thNight
66%6%9%10%6%
2594
16th to endNight
64%6%13%11%3
2704
February1st to 15thNight
61%6%11%14%4
2482
16th to endNight
58%6%11%16%6%
2078
March1st to 15thNight
54%6%10%19%8%1
2197
16th to endNight
46%6%11%24%10%1
2178
April1st to 15thNight
49%5%11%19%11%1
1837
16th to endNight
42%5%11%19%17%4
1620
May1st to 15thNight
47%7%11%18%12%3
1620
16th to endNight
38%7%11%23%17%1
1621
June1st to 15thNight
35%7%12%26%15%1
1389
16th to endNight
33%8%12%23%20%1
1260
July1st to 15thNight
30%5%10%26%23%3
1336
16th to endNight
29%7%14%25%19%3
1595
August1st to 15thNight
27%9%14%31%14%2
1609
16th to endNight
30%6%12%29%18%2
1719
September1st to 15thNight
36%7%11%24%17%2
1923
16th to endNight
36%6%12%28%16%1
1980
October1st to 15thNight
41%7%11%19%19%
2115
16th to endNight
52%7%14%17%7%
2336
November1st to 15thNight
47%7%13%19%11%1
2471
16th to endNight
57%6%13%16%5%
2707
December1st to 15thNight
64%8%12%9%4
2730
16th to endNight
70%7%9%8%2
2892

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
24%7%41%17%9%
135
16th to endDay
30%7%38%20%2
144
February1st to 15thDay
25%11%35%24%2
135
16th to endDay
24%7%35%32%
120
March1st to 15thDay
20%17%23%28%9%
278
16th to endDay
20%11%25%31%8%1
311
April1st to 15thDay
20%14%25%28%9%1
270
16th to endDay
17%12%24%28%10%6%
270
May1st to 15thDay
18%12%19%28%18%2
288
16th to endDay
13%10%18%28%23%5%
331
June1st to 15thDay
11%11%12%37%24%2
362
16th to endDay
11%13%15%33%20%4
495
July1st to 15thDay
9%10%12%31%30%6%
450
16th to endDay
7%10%10%29%33%8%
326
August1st to 15thDay
8%7%9%37%26%11%
313
16th to endDay
10%7%9%25%36%11%
332
September1st to 15thDay
11%7%13%24%29%14%
315
16th to endDay
16%6%11%18%28%18%
314
October1st to 15thDay
16%10%18%26%19%7%
315
16th to endDay
22%15%27%23%9%1
303
November1st to 15thDay
20%6%24%25%17%4
135
16th to endDay
24%15%27%25%6%
94
December1st to 15thDay
22%21%31%21%4
90
16th to endDay
26%27%34%7%2
101
January1st to 15thNight
23%24%31%16%4
853
16th to endNight
21%23%26%21%6%
832
February1st to 15thNight
22%20%29%22%4
764
16th to endNight
21%18%24%29%6%
683
March1st to 15thNight
19%18%25%27%8%
780
16th to endNight
17%19%23%26%10%2
792
April1st to 15thNight
18%19%21%31%7%
662
16th to endNight
12%20%20%32%11%2
540
May1st to 15thNight
15%18%17%27%17%2
540
16th to endNight
11%18%12%30%22%4
500
June1st to 15thNight
11%18%13%35%19%1
360
16th to endNight
10%17%11%33%25%2
360
July1st to 15thNight
7%12%9%32%32%5%
464
16th to endNight
6%17%11%29%29%4
564
August1st to 15thNight
7%10%8%35%29%8%
539
16th to endNight
9%9%10%25%37%6%
573
September1st to 15thNight
12%11%11%24%29%10%
717
16th to endNight
13%10%13%24%27%10%
717
October1st to 15thNight
20%13%15%24%22%4
720
16th to endNight
24%18%26%22%7%
768
November1st to 15thNight
18%20%21%25%11%2
760
16th to endNight
25%29%22%13%8%
780
December1st to 15thNight
26%26%25%14%5%
780
16th to endNight
25%26%29%15%2
835
Page generated at 2018-03-22 11:34:26. Version ac04

Copyright 2018 A. Danko


Rondeau Provincial Park Clear Sky Chart |Charts Home