Rivière-à-Pierre Village
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Rivière-à-Pierre Village clear sky chart from 2005-11-05 to 2017-10-31.

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
25%
14765
12%
47405
6%
14733
33%
14733
14%
34279

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%
720
11%
2506
3%
716
21%
716
8%
1949
January16th to endNight
20%
768
11%
2688
4%
768
29%
768
10%
2008
February1st to 15thNight
17%
704
11%
2363
4%
701
28%
701
11%
1753
February16th to endNight
19%
631
12%
1893
6%
631
28%
631
13%
1440
March1st to 15thNight
17%
720
15%
2160
6%
720
27%
720
13%
1606
March16th to endNight
25%
768
20%
2014
6%
768
35%
768
19%
1412
April1st to 15thNight
22%
718
16%
1796
4%
718
28%
718
16%
1372
April16th to endNight
20%
561
15%
1641
5%
561
29%
561
16%
1133
May1st to 15thNight
26%
417
15%
1497
10%
417
35%
417
16%
1002
May16th to endNight
25%
375
10%
1497
8%
374
35%
374
12%
1024
June1st to 15thNight
32%
360
7%
1299
6%
360
37%
360
14%
913
June16th to endNight
36%
360
7%
1295
7%
360
39%
360
16%
894
July1st to 15thNight
48%
340
7%
1360
10%
340
50%
340
19%
868
July16th to endNight
47%
376
10%
1418
13%
354
50%
354
19%
903
August1st to 15thNight
50%
385
11%
1456
12%
383
54%
383
19%
962
August16th to endNight
43%
673
15%
1819
9%
673
47%
673
26%
1216
September1st to 15thNight
38%
720
12%
1824
5%
720
41%
720
27%
1259
September16th to endNight
38%
717
18%
1980
10%
717
44%
717
27%
1294
October1st to 15thNight
28%
720
17%
2094
8%
720
38%
720
20%
1458
October16th to endNight
21%
768
11%
2494
6%
768
28%
768
13%
1866
November1st to 15thNight
22%
700
16%
2277
8%
700
32%
700
14%
1658
November16th to endNight
22%
728
12%
2538
7%
728
30%
728
11%
1882
December1st to 15thNight
14%
750
7%
2700
2%
750
20%
750
7%
2149
December16th to endNight
11%
786
10%
2796
2%
786
21%
786
6%
2258

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
22%10%46%5%34446%27%
48338
Night
20%10%46%5%34446%29%
47575
TransparencyDay
57%411%17%8%
48026
Night
55%311%19%8%
47405
SeeingDay
28%14%28%18%8%2
6037
Night
26%12%26%23%8%
14765

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
20%17%6%7%8%445%3319%
1432
16th to endDay
15%14%7%9%6%36%5%5%6%20%
1536
February1st to 15thDay
10%16%7%11%8%45%445%21%
1495
16th to endDay
15%16%6%10%5%35%44424%
1580
March1st to 15thDay
19%11%5%8%43434329%
1790
16th to endDay
15%10%47%7%34445%32%
2208
April1st to 15thDay
25%10%36%5%3423430%
2152
16th to endDay
23%10%25%5%3333434%
2318
May1st to 15thDay
24%8%35%6%2444430%
2463
16th to endDay
25%7%46%5%3445%6%26%
2618
June1st to 15thDay
25%7%35%5%35%45%6%26%
2658
16th to endDay
24%7%5%6%5%35%45%6%25%
2661
July1st to 15thDay
20%6%36%6%36%5%6%7%27%
2520
16th to endDay
19%6%26%6%45%5%6%8%26%
2654
August1st to 15thDay
21%6%37%5%36%6%7%7%23%
2481
16th to endDay
16%6%25%5%36%5%6%8%32%
2381
September1st to 15thDay
22%6%24434445%36%
2136
16th to endDay
22%5%2442436%6%37%
1980
October1st to 15thDay
30%7%25%5%35%336%27%
1865
16th to endDay
29%12%36%6%25%236%19%
1728
November1st to 15thDay
22%12%47%6%34335%25%
1581
16th to endDay
24%15%5%6%5%23335%24%
1416
December1st to 15thDay
27%17%46%5%3222422%
1260
16th to endDay
24%15%6%7%6%2343420%
1425
January1st to 15thNight
20%17%6%8%6%24346%19%
2506
16th to endNight
13%15%5%8%7%35%45%5%23%
2688
February1st to 15thNight
10%11%6%10%10%4445%6%24%
2362
16th to endNight
16%15%5%9%5%25%345%25%
1893
March1st to 15thNight
19%12%46%6%25%436%28%
2147
16th to endNight
13%10%45%436%45%6%36%
2014
April1st to 15thNight
26%9%36%424445%29%
1796
16th to endNight
23%8%245%24246%36%
1641
May1st to 15thNight
23%7%35%5%24335%35%
1497
16th to endNight
26%6%35%5%24346%31%
1495
June1st to 15thNight
25%6%45%5%335%5%6%29%
1299
16th to endNight
22%7%35%425%45%7%30%
1295
July1st to 15thNight
17%5%36%436%5%6%8%33%
1440
16th to endNight
15%5%25%5%36%5%5%6%38%
1514
August1st to 15thNight
16%5%26%445%6%5%8%33%
1466
16th to endNight
16%5%25%5%3445%8%38%
1819
September1st to 15thNight
20%6%24423345%41%
1824
16th to endNight
22%423324246%43%
1980
October1st to 15thNight
22%7%35%423346%35%
2094
16th to endNight
29%9%25%424446%26%
2494
November1st to 15thNight
22%9%36%5%34446%29%
2277
16th to endNight
25%14%36%42334427%
2538
December1st to 15thNight
25%15%5%8%5%2433419%
2700
16th to endNight
21%18%6%8%6%3442319%
2796

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
69%46%13%5%
1433
16th to endDay
63%37%16%7%
1536
February1st to 15thDay
64%210%14%7%
1498
16th to endDay
63%36%16%8%1
1580
March1st to 15thDay
59%29%14%11%1
1800
16th to endDay
53%36%18%15%2
2208
April1st to 15thDay
59%27%16%10%3
2152
16th to endDay
54%29%16%14%2
2318
May1st to 15thDay
56%38%17%12%1
2463
16th to endDay
59%48%16%10%
2622
June1st to 15thDay
56%5%10%18%8%1
2658
16th to endDay
58%412%15%8%
2661
July1st to 15thDay
52%415%19%6%
2371
16th to endDay
55%6%14%17%5%
2487
August1st to 15thDay
56%6%17%16%3
2467
16th to endDay
47%5%17%23%5%
2381
September1st to 15thDay
49%414%23%8%
2136
16th to endDay
47%315%25%7%
1980
October1st to 15thDay
58%311%18%7%
1865
16th to endDay
66%310%16%2
1728
November1st to 15thDay
61%49%18%6%
1581
16th to endDay
63%310%17%4
1416
December1st to 15thDay
67%211%15%3
1260
16th to endDay
67%36%14%7%
1425
January1st to 15thNight
67%28%16%4
2506
16th to endNight
61%39%17%8%
2688
February1st to 15thNight
59%310%18%8%
2363
16th to endNight
61%29%15%10%
1893
March1st to 15thNight
57%38%16%11%1
2160
16th to endNight
48%39%20%14%3
2014
April1st to 15thNight
56%35%19%12%2
1796
16th to endNight
50%39%20%13%2
1641
May1st to 15thNight
51%310%19%12%2
1497
16th to endNight
54%310%19%10%1
1497
June1st to 15thNight
54%413%20%6%
1299
16th to endNight
52%411%18%10%1
1295
July1st to 15thNight
45%6%19%21%7%
1360
16th to endNight
45%5%17%22%8%
1418
August1st to 15thNight
46%6%21%21%3
1456
16th to endNight
42%5%19%26%6%
1819
September1st to 15thNight
44%315%26%8%
1824
16th to endNight
42%316%30%7%
1980
October1st to 15thNight
49%312%23%9%
2094
16th to endNight
58%411%20%4
2494
November1st to 15thNight
56%411%17%8%1
2277
16th to endNight
60%310%19%6%
2538
December1st to 15thNight
68%311%13%4
2700
16th to endNight
70%37%12%6%
2796

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
36%15%36%11%
60
16th to endDay
28%18%37%9%41
64
February1st to 15thDay
26%20%37%10%42
99
16th to endDay
25%21%29%17%5%
239
March1st to 15thDay
30%19%25%19%4
270
16th to endDay
20%22%25%20%8%2
288
April1st to 15thDay
35%16%30%11%41
270
16th to endDay
30%21%24%15%5%2
270
May1st to 15thDay
37%12%28%14%5%
288
16th to endDay
29%18%29%17%5%
331
June1st to 15thDay
28%12%29%19%8%
453
16th to endDay
24%11%30%21%9%1
456
July1st to 15thDay
25%10%29%22%9%1
305
16th to endDay
22%7%30%26%10%1
326
August1st to 15thDay
24%7%27%23%12%3
313
16th to endDay
19%10%28%23%12%5%
332
September1st to 15thDay
24%8%28%22%10%4
315
16th to endDay
19%14%28%16%14%6%
314
October1st to 15thDay
31%12%28%16%9%1
310
16th to endDay
37%14%24%15%6%
288
November1st to 15thDay
33%13%26%17%8%1
235
16th to endDay
39%16%26%16%2
87
December1st to 15thDay
40%6%40%10%3
60
16th to endDay
43%21%29%4
64
January1st to 15thNight
28%14%33%18%4
720
16th to endNight
22%17%29%22%6%
768
February1st to 15thNight
17%18%34%22%6%
704
16th to endNight
26%16%30%19%6%
631
March1st to 15thNight
28%16%30%19%4
720
16th to endNight
21%19%27%21%7%2
768
April1st to 15thNight
33%12%26%22%5%
718
16th to endNight
28%18%27%17%6%
561
May1st to 15thNight
27%11%29%22%9%
417
16th to endNight
31%9%27%22%8%
375
June1st to 15thNight
26%8%24%31%8%
360
16th to endNight
24%423%35%11%
360
July1st to 15thNight
17%324%35%17%
340
16th to endNight
19%321%38%17%
376
August1st to 15thNight
20%415%38%19%
385
16th to endNight
19%8%21%33%15%2
673
September1st to 15thNight
24%6%24%30%12%1
720
16th to endNight
24%9%23%24%17%1
717
October1st to 15thNight
27%12%25%24%8%1
720
16th to endNight
35%11%25%19%7%
768
November1st to 15thNight
27%13%30%19%7%1
700
16th to endNight
35%14%21%19%8%1
728
December1st to 15thNight
33%17%24%20%4
750
16th to endNight
33%16%26%17%4
786
Page generated at 2017-11-01 17:23:42. Version ac04

Copyright 2017 A. Danko


Rivière-à-Pierre Village Clear Sky Chart |Charts Home