Rouyn-Noranda
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Rouyn-Noranda clear sky chart from 2005-11-05 to 2017-09-16.

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
27%
14985
9%
46711
6%
14952
30%
14952
13%
36200

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%
900
5%
2685
3%
895
17%
895
6%
2337
January16th to endNight
23%
849
7%
2688
3%
849
26%
849
7%
2249
February1st to 15thNight
24%
704
9%
2287
6%
701
29%
701
10%
1829
February16th to endNight
19%
631
7%
2051
3%
631
25%
631
9%
1674
March1st to 15thNight
25%
720
12%
2019
8%
720
29%
720
12%
1609
March16th to endNight
32%
768
17%
2103
10%
768
37%
768
20%
1525
April1st to 15thNight
25%
695
13%
1773
6%
695
28%
695
18%
1339
April16th to endNight
31%
540
16%
1620
10%
540
38%
540
21%
1142
May1st to 15thNight
30%
372
13%
1452
13%
372
38%
372
15%
999
May16th to endNight
38%
375
9%
1460
9%
374
44%
374
15%
1003
June1st to 15thNight
34%
360
7%
1260
5%
360
38%
360
16%
882
June16th to endNight
43%
360
7%
1260
5%
360
44%
360
22%
796
July1st to 15thNight
42%
340
7%
1190
6%
340
44%
340
21%
766
July16th to endNight
47%
376
11%
1323
14%
354
50%
354
20%
849
August1st to 15thNight
42%
491
9%
1562
8%
489
46%
489
19%
1092
August16th to endNight
41%
594
14%
1740
10%
594
44%
594
23%
1177
September1st to 15thNight
37%
720
10%
1800
5%
720
39%
720
24%
1311
September16th to endNight
39%
658
15%
1834
9%
658
42%
658
24%
1269
October1st to 15thNight
24%
660
10%
1980
7%
660
28%
660
12%
1542
October16th to endNight
19%
704
6%
2184
5%
704
21%
704
8%
1846
November1st to 15thNight
18%
700
8%
2452
6%
700
22%
700
8%
1995
November16th to endNight
14%
720
6%
2520
4%
720
17%
720
6%
2149
December1st to 15thNight
14%
788
4%
2588
1%
788
18%
788
5%
2248
December16th to endNight
16%
960
5%
2880
4%
960
17%
960
5%
2572

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
19%11%47%6%35%45%6%25%
48051
Night
18%12%5%8%6%35%445%24%
46867
TransparencyDay
59%5%10%16%6%
47724
Night
61%5%10%15%6%
46712
SeeingDay
25%11%28%22%9%2
5884
Night
25%9%28%25%9%1
14985

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
21%16%7%12%7%2346%5%10%
1253
16th to endDay
13%19%6%10%8%47%6%5%6%12%
1533
February1st to 15thDay
9%14%6%10%9%5%8%6%5%7%16%
1575
16th to endDay
13%16%8%10%7%45%44419%
1422
March1st to 15thDay
17%10%48%7%36%5%3426%
1928
16th to endDay
12%11%47%5%46%45%5%31%
2121
April1st to 15thDay
22%13%46%5%34445%27%
2185
16th to endDay
18%10%47%5%34345%32%
2340
May1st to 15thDay
19%10%36%6%35%446%29%
2498
16th to endDay
23%9%45%433345%32%
2652
June1st to 15thDay
21%7%37%6%35%45%7%28%
2700
16th to endDay
17%7%36%5%36%5%6%6%30%
2700
July1st to 15thDay
17%7%36%5%345%6%9%29%
2700
16th to endDay
17%6%37%6%35%5%5%8%30%
2754
August1st to 15thDay
20%8%36%7%46%5%6%6%25%
2386
16th to endDay
19%8%36%5%445%5%8%28%
2450
September1st to 15thDay
21%7%36%5%245%5%7%30%
2160
16th to endDay
24%8%35%423345%32%
1797
October1st to 15thDay
25%12%36%42444425%
1650
16th to endDay
30%19%48%6%25%33412%
1686
November1st to 15thDay
23%18%6%9%5%24335%17%
1406
16th to endDay
26%17%8%12%7%3322311%
1440
December1st to 15thDay
21%18%7%11%7%245%45%11%
1371
16th to endDay
17%21%6%12%8%46%3349%
1344
January1st to 15thNight
18%18%8%12%9%35%34312%
2685
16th to endNight
14%15%6%11%9%46%5%6%5%13%
2688
February1st to 15thNight
11%14%7%9%12%47%446%18%
2285
16th to endNight
14%16%8%10%7%46%34418%
2051
March1st to 15thNight
17%12%6%9%7%45%35%423%
2007
16th to endNight
12%11%47%5%35%445%34%
2103
April1st to 15thNight
21%11%46%5%33445%30%
1773
16th to endNight
19%9%46%5%23336%35%
1620
May1st to 15thNight
19%8%36%5%34446%32%
1452
16th to endNight
21%7%25%425%46%6%32%
1459
June1st to 15thNight
18%8%37%5%435%46%33%
1260
16th to endNight
12%436%5%26%5%5%8%39%
1260
July1st to 15thNight
15%6%35%435%5%5%8%35%
1260
16th to endNight
13%5%26%5%35%5%5%8%37%
1414
August1st to 15thNight
15%7%36%8%45%45%6%33%
1572
16th to endNight
16%5%36%6%3445%7%37%
1740
September1st to 15thNight
18%7%35%5%335%5%5%36%
1800
16th to endNight
21%5%25%413446%38%
1834
October1st to 15thNight
22%13%5%6%5%34445%25%
1980
16th to endNight
26%19%47%5%24435%16%
2184
November1st to 15thNight
22%15%6%8%5%4433419%
2452
16th to endNight
27%17%6%9%6%2333414%
2520
December1st to 15thNight
19%20%7%12%7%3443312%
2588
16th to endNight
20%19%7%11%9%45%43310%
2880

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
74%38%11%2
1254
16th to endDay
70%5%6%10%6%
1533
February1st to 15thDay
66%5%9%12%5%
1577
16th to endDay
67%28%15%4
1422
March1st to 15thDay
61%48%15%9%
1939
16th to endDay
53%49%21%9%2
2121
April1st to 15thDay
59%48%16%9%1
2185
16th to endDay
53%5%9%17%12%1
2340
May1st to 15thDay
55%5%8%17%12%1
2498
16th to endDay
54%5%9%19%9%
2656
June1st to 15thDay
54%5%11%19%9%
2700
16th to endDay
51%7%13%18%9%1
2700
July1st to 15thDay
47%7%15%21%7%
2541
16th to endDay
53%6%12%23%4
2582
August1st to 15thDay
57%8%12%18%2
2372
16th to endDay
52%6%16%18%5%
2450
September1st to 15thDay
52%6%15%18%5%
2160
16th to endDay
52%5%14%23%4
1797
October1st to 15thDay
61%5%12%12%6%1
1650
16th to endDay
77%46%7%3
1686
November1st to 15thDay
70%411%8%3
1406
16th to endDay
80%27%7%2
1440
December1st to 15thDay
75%310%8%1
1371
16th to endDay
79%46%6%2
1344
January1st to 15thNight
76%48%8%2
2685
16th to endNight
71%47%11%4
2688
February1st to 15thNight
67%39%12%6%
2287
16th to endNight
68%47%12%5%
2051
March1st to 15thNight
64%38%13%9%
2019
16th to endNight
52%39%18%12%2
2103
April1st to 15thNight
56%38%17%12%1
1773
16th to endNight
50%47%19%16%1
1620
May1st to 15thNight
52%5%9%17%13%1
1452
16th to endNight
50%7%11%17%10%2
1461
June1st to 15thNight
52%5%9%20%11%1
1260
16th to endNight
41%6%14%24%11%1
1260
July1st to 15thNight
42%7%16%24%8%
1190
16th to endNight
44%6%17%25%6%
1323
August1st to 15thNight
49%6%17%21%4
1562
16th to endNight
43%7%18%24%5%
1740
September1st to 15thNight
47%6%19%18%6%1
1800
16th to endNight
45%6%16%26%5%
1834
October1st to 15thNight
61%5%12%12%7%
1980
16th to endNight
71%5%9%10%3
2184
November1st to 15thNight
69%412%10%3
2452
16th to endNight
74%48%9%2
2520
December1st to 15thNight
77%47%9%1
2588
16th to endNight
80%36%6%3
2880

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%16%38%10%5%
60
16th to endDay
35%15%23%18%6%1
77
February1st to 15thDay
21%10%34%31%3
90
16th to endDay
27%20%38%12%1
81
March1st to 15thDay
23%10%36%18%9%
260
16th to endDay
20%12%33%21%9%2
288
April1st to 15thDay
26%15%25%22%7%2
270
16th to endDay
24%17%26%19%10%2
270
May1st to 15thDay
28%10%22%24%8%5%
288
16th to endDay
31%11%26%20%7%2
365
June1st to 15thDay
26%12%27%23%9%1
495
16th to endDay
17%13%26%28%10%3
495
July1st to 15thDay
20%8%29%26%12%1
475
16th to endDay
19%6%29%29%12%3
425
August1st to 15thDay
22%5%22%27%13%8%
313
16th to endDay
25%7%26%18%14%6%
332
September1st to 15thDay
21%8%26%24%14%5%
315
16th to endDay
25%8%29%21%11%3
254
October1st to 15thDay
29%10%30%21%5%1
255
16th to endDay
38%14%22%16%6%2
232
November1st to 15thDay
23%21%40%10%5%
60
16th to endDay
48%13%30%5%3
60
December1st to 15thDay
26%16%43%8%5%
60
16th to endDay
32%21%35%7%1
64
January1st to 15thNight
29%12%30%21%5%
900
16th to endNight
22%8%30%25%10%1
849
February1st to 15thNight
19%9%32%30%6%
704
16th to endNight
24%8%33%24%7%
631
March1st to 15thNight
24%17%27%24%5%
720
16th to endNight
19%10%32%28%8%1
768
April1st to 15thNight
26%14%28%22%6%
695
16th to endNight
24%8%31%27%7%1
540
May1st to 15thNight
24%7%31%24%11%
372
16th to endNight
25%5%25%33%7%1
375
June1st to 15thNight
23%8%28%29%10%
360
16th to endNight
15%5%30%33%16%
360
July1st to 15thNight
16%6%27%37%10%1
340
16th to endNight
16%5%25%36%16%
376
August1st to 15thNight
21%422%28%21%2
491
16th to endNight
19%5%26%29%16%1
594
September1st to 15thNight
22%6%28%27%14%1
720
16th to endNight
24%8%23%28%14%1
658
October1st to 15thNight
30%12%26%21%7%1
660
16th to endNight
39%8%25%18%5%1
704
November1st to 15thNight
31%13%29%18%5%1
700
16th to endNight
38%9%28%18%4
720
December1st to 15thNight
32%12%28%19%6%1
788
16th to endNight
30%11%26%22%7%1
960
Page generated at 2017-09-16 17:07:01. Version ac04

Copyright 2017 A. Danko


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