Jasper Athabasca Glacier
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Jasper Athabasca Glacier clear sky chart from 2005-11-06 to 2024-03-01.

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%
23508
7%
81010
4%
23393
28%
23393
10%
63243

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 10thNight
17%
1018
4%
4997
3%
992
20%
992
4%
4342
January11th to 20thNight
19%
840
18%
4413
5%
826
23%
826
7%
3001
January21st to endNight
14%
835
6%
4859
4%
814
21%
814
4%
4170
February1st to 10thNight
20%
760
6%
2660
4%
760
23%
760
8%
2149
February11th to 20thNight
19%
744
7%
2491
4%
740
24%
740
11%
1952
February21st to endNight
29%
628
10%
1884
6%
628
35%
628
13%
1503
March1st to 10thNight
20%
722
8%
2165
5%
722
24%
722
11%
1739
March11th to 20thNight
18%
720
7%
2111
4%
720
20%
720
11%
1705
March21st to endNight
19%
792
4%
2002
1%
792
20%
792
9%
1722
April1st to 10thNight
22%
720
4%
1800
2%
720
23%
720
10%
1527
April11th to 20thNight
25%
576
7%
1644
4%
576
28%
576
13%
1300
April21st to endNight
29%
452
6%
1532
6%
452
31%
452
11%
1201
May1st to 10thNight
37%
360
4%
1440
5%
360
39%
360
10%
1093
May11th to 20thNight
46%
354
7%
1299
8%
354
47%
354
17%
867
May21st to endNight
37%
388
2%
1358
0%
388
37%
388
11%
1042
June1st to 10thNight
31%
360
0%
1182
0%
360
31%
360
13%
888
June11th to 20thNight
25%
360
0%
1080
0%
360
25%
360
8%
922
June21st to endNight
42%
360
0%
1080
0%
360
42%
360
18%
797
July1st to 10thNight
49%
350
0%
1050
0%
350
49%
350
22%
718
July11th to 20thNight
43%
348
3%
1154
0%
348
43%
348
18%
783
July21st to endNight
59%
394
7%
1460
10%
372
60%
372
25%
847
August1st to 10thNight
60%
358
7%
1424
13%
356
61%
356
20%
879
August11th to 20thNight
56%
360
16%
1428
23%
360
58%
360
20%
881
August21st to endNight
40%
634
12%
1822
10%
634
41%
634
20%
1316
September1st to 10thNight
37%
720
12%
1800
7%
720
39%
720
22%
1310
September11th to 20thNight
40%
720
12%
1885
7%
720
42%
720
21%
1372
September21st to endNight
28%
720
12%
1980
7%
720
32%
720
15%
1527
October1st to 10thNight
30%
720
8%
2087
7%
720
32%
720
16%
1587
October11th to 20thNight
23%
720
7%
2322
4%
720
27%
720
11%
1805
October21st to endNight
15%
792
6%
2574
3%
792
19%
792
8%
2093
November1st to 10thNight
14%
740
5%
2470
3%
740
17%
740
6%
2098
November11th to 20thNight
13%
945
5%
2845
3%
945
16%
945
8%
2380
November21st to endNight
15%
950
5%
2850
2%
950
19%
950
10%
2329
December1st to 10thNight
18%
950
10%
2850
6%
950
23%
950
11%
2290
December11th to 20thNight
17%
959
4%
3539
3%
958
19%
958
7%
3039
December21st to endNight
15%
1139
4%
5473
2%
1114
19%
1114
6%
4069

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
6%14%8%15%10%5%6%5%5%6%20%
77964
Night
412%8%17%12%5%6%5%6%6%18%
81394
TransparencyDay
58%11%12%12%6%1
77668
Night
58%11%12%11%7%1
81270
SeeingDay
15%19%28%24%12%3
14838
Night
12%18%35%24%11%2
23528

By Month

Percentage Cloud Cover NW (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 10thDay
18%8%25%15%11%11%6%6%37%
1938
11th to 20thDay
18%6%19%13%5%6%6%6%326%
2396
21st to endDay
14%10%32%13%45%5%4410%
2794
February1st to 10thDay
210%10%24%14%5%6%5%5%5%14%
1520
11th to 20thDay
19%9%18%17%7%6%7%6%6%14%
1574
21st to endDay
17%8%18%18%8%10%6%6%5%13%
1570
March1st to 10thDay
114%10%19%16%6%6%7%5%412%
1801
11th to 20thDay
112%12%20%13%5%8%7%4415%
1849
21st to endDay
115%12%22%12%7%7%5%4410%
2353
April1st to 10thDay
414%11%19%15%7%8%6%5%5%8%
2160
11th to 20thDay
317%11%16%11%6%8%5%46%13%
2267
21st to endDay
420%8%15%10%5%6%5%5%7%15%
2425
May1st to 10thDay
7%22%9%12%9%47%5%6%5%15%
2520
11th to 20thDay
8%17%6%9%7%37%5%6%7%25%
2592
21st to endDay
13%18%7%9%8%46%5%5%8%19%
2917
June1st to 10thDay
16%18%6%9%8%46%5%5%6%17%
2775
11th to 20thDay
16%20%8%11%7%45%5%5%7%13%
2880
21st to endDay
12%14%5%10%8%5%6%5%6%6%24%
2880
July1st to 10thDay
10%12%49%7%46%5%6%8%28%
2880
11th to 20thDay
9%8%5%9%8%48%7%7%9%27%
2766
21st to endDay
6%9%47%6%46%5%7%9%38%
2769
August1st to 10thDay
8%9%49%6%447%8%9%32%
2507
11th to 20thDay
9%8%47%8%35%6%7%8%34%
2471
21st to endDay
11%12%6%8%8%5%6%5%6%7%26%
2533
September1st to 10thDay
8%15%5%10%8%5%6%5%5%6%28%
2160
11th to 20thDay
9%16%5%10%6%345%6%7%29%
2075
21st to endDay
11%21%6%10%7%445%5%6%22%
1980
October1st to 10thDay
8%16%9%12%8%46%5%46%24%
1872
11th to 20thDay
6%17%10%13%10%45%6%6%7%16%
1638
21st to endDay
5%19%9%20%11%6%5%445%13%
1782
November1st to 10thDay
419%13%18%13%5%5%44411%
1594
11th to 20thDay
214%9%20%13%5%7%6%5%415%
1330
21st to endDay
113%9%20%15%5%6%5%45%17%
1330
December1st to 10thDay
211%7%17%15%6%7%6%45%21%
1330
11th to 20thDay
11%11%25%15%6%6%5%5%412%
1646
21st to endDay
6%9%23%13%5%5%6%6%6%21%
2090
January1st to 10thNight
18%8%25%23%6%7%5%5%38%
5003
11th to 20thNight
16%5%17%14%5%7%7%8%7%23%
4533
21st to endNight
12%14%32%13%45%4448%
4862
February1st to 10thNight
29%8%22%15%6%6%6%6%5%15%
2660
11th to 20thNight
19%9%21%17%7%7%5%5%5%16%
2489
21st to endNight
17%9%16%16%7%9%6%6%7%16%
1884
March1st to 10thNight
18%11%22%15%7%6%5%5%5%15%
2165
11th to 20thNight
211%11%21%16%5%6%5%5%5%14%
2110
21st to endNight
215%12%22%15%5%6%5%4411%
2002
April1st to 10thNight
312%12%23%12%5%6%5%5%6%12%
1800
11th to 20thNight
217%10%15%11%6%6%6%7%5%16%
1644
21st to endNight
5%16%8%13%9%6%5%6%5%7%20%
1532
May1st to 10thNight
6%21%7%10%8%5%6%5%7%7%20%
1440
11th to 20thNight
8%11%49%7%46%6%6%9%29%
1299
21st to endNight
12%20%49%6%46%5%6%7%21%
1358
June1st to 10thNight
16%18%48%5%46%47%8%20%
1182
11th to 20thNight
18%20%7%13%7%46%5%6%6%10%
1080
21st to endNight
13%14%5%11%7%46%5%5%7%24%
1080
July1st to 10thNight
10%12%5%7%6%36%5%7%8%30%
1080
11th to 20thNight
11%10%5%7%8%5%7%5%6%8%29%
1192
21st to endNight
8%8%46%5%45%5%6%7%40%
1546
August1st to 10thNight
7%9%37%5%45%7%8%10%36%
1432
11th to 20thNight
9%7%46%6%46%7%8%9%35%
1428
21st to endNight
11%12%49%8%5%6%6%6%7%26%
1822
September1st to 10thNight
10%16%6%9%6%3446%7%30%
1800
11th to 20thNight
10%17%6%9%6%44447%29%
1885
21st to endNight
10%17%7%10%6%36%45%7%25%
1980
October1st to 10thNight
5%17%8%11%7%46%5%7%6%25%
2087
11th to 20thNight
7%16%9%15%10%46%5%5%7%17%
2322
21st to endNight
218%12%20%12%45%446%13%
2574
November1st to 10thNight
419%12%19%13%44446%10%
2470
11th to 20thNight
112%11%23%16%6%6%5%4414%
2845
21st to endNight
112%10%20%15%6%7%5%5%6%14%
2850
December1st to 10thNight
111%9%16%15%8%8%5%46%18%
2850
11th to 20thNight
7%11%24%16%8%8%6%6%410%
3542
21st to endNight
18%8%19%15%6%7%6%8%8%15%
5566

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 10thDay
67%14%9%5%32
1938
11th to 20thDay
52%9%11%9%11%8%
2420
21st to endDay
67%14%8%6%41
2794
February1st to 10thDay
63%10%12%5%7%3
1520
11th to 20thDay
63%9%11%9%6%2
1582
21st to endDay
62%12%10%10%42
1570
March1st to 10thDay
66%10%13%6%41
1801
11th to 20thDay
64%11%10%10%5%
1849
21st to endDay
73%9%9%6%31
2353
April1st to 10thDay
74%9%10%5%2
2160
11th to 20thDay
67%9%12%8%3
2267
21st to endDay
69%9%11%9%3
2425
May1st to 10thDay
68%9%11%9%2
2520
11th to 20thDay
54%10%15%15%6%
2596
21st to endDay
62%8%13%13%4
2918
June1st to 10thDay
63%10%11%12%31
2775
11th to 20thDay
65%9%11%11%3
2880
21st to endDay
54%11%12%17%5%1
2880
July1st to 10thDay
45%11%14%21%8%1
2801
11th to 20thDay
47%11%15%19%8%
2681
21st to endDay
40%10%15%24%10%
2615
August1st to 10thDay
49%11%15%18%6%
2490
11th to 20thDay
43%12%16%19%9%
2471
21st to endDay
51%10%11%20%6%1
2533
September1st to 10thDay
50%11%16%17%5%1
2160
11th to 20thDay
49%10%12%20%9%
2075
21st to endDay
59%8%11%14%6%1
1980
October1st to 10thDay
56%11%11%17%4
1872
11th to 20thDay
55%14%15%13%3
1638
21st to endDay
65%9%13%7%5%
1782
November1st to 10thDay
67%10%9%8%5%2
1594
11th to 20thDay
60%14%11%8%5%1
1330
21st to endDay
57%14%13%7%5%3
1330
December1st to 10thDay
58%11%9%11%9%2
1330
11th to 20thDay
64%13%10%6%5%2
1648
21st to endDay
48%14%14%12%9%2
2090
January1st to 10thNight
72%10%9%342
5003
11th to 20thNight
51%10%8%9%17%6%
4571
21st to endNight
70%11%8%5%5%1
4862
February1st to 10thNight
63%10%11%7%6%3
2660
11th to 20thNight
58%11%15%7%7%1
2491
21st to endNight
59%10%12%11%6%3
1884
March1st to 10thNight
60%10%13%9%7%1
2165
11th to 20thNight
58%12%13%9%6%1
2111
21st to endNight
67%10%11%7%5%
2002
April1st to 10thNight
64%11%14%8%3
1800
11th to 20thNight
59%9%14%11%7%
1644
21st to endNight
57%12%12%13%6%1
1532
May1st to 10thNight
57%11%14%14%5%
1440
11th to 20thNight
46%9%15%21%9%
1299
21st to endNight
60%7%11%14%7%
1358
June1st to 10thNight
56%9%13%16%6%1
1182
11th to 20thNight
68%9%11%8%4
1080
21st to endNight
48%12%16%18%6%
1080
July1st to 10thNight
43%10%15%20%11%1
1050
11th to 20thNight
44%11%15%24%6%
1154
21st to endNight
31%12%16%29%11%1
1460
August1st to 10thNight
37%12%20%26%5%
1424
11th to 20thNight
36%13%18%27%7%
1428
21st to endNight
47%10%15%19%8%1
1822
September1st to 10thNight
45%10%15%21%7%1
1800
11th to 20thNight
50%7%15%17%10%
1885
21st to endNight
52%11%14%14%8%1
1980
October1st to 10thNight
54%9%14%18%5%
2087
11th to 20thNight
55%13%13%14%5%
2322
21st to endNight
64%9%11%10%6%1
2574
November1st to 10thNight
69%10%9%7%42
2470
11th to 20thNight
63%12%11%7%6%2
2845
21st to endNight
60%12%11%8%5%3
2850
December1st to 10thNight
59%11%8%10%10%2
2850
11th to 20thNight
67%12%9%7%41
3539
21st to endNight
55%12%14%9%7%2
5566

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 10thDay
10%23%31%22%11%3
180
11th to 20thDay
9%27%32%19%10%2
180
21st to endDay
14%26%39%14%5%4
198
February1st to 10thDay
17%31%31%12%7%2
180
11th to 20thDay
12%21%37%20%8%3
261
21st to endDay
12%23%35%22%7%1
382
March1st to 10thDay
14%27%32%16%10%2
421
11th to 20thDay
10%29%32%19%6%2
420
21st to endDay
10%30%29%20%8%2
462
April1st to 10thDay
17%23%32%21%5%2
420
11th to 20thDay
13%25%30%20%9%3
412
21st to endDay
14%23%33%18%9%3
420
May1st to 10thDay
19%17%28%24%10%2
423
11th to 20thDay
14%9%21%32%18%6%
563
21st to endDay
17%13%18%26%21%4
679
June1st to 10thDay
21%12%28%25%13%1
705
11th to 20thDay
20%14%26%27%12%1
810
21st to endDay
16%8%23%28%20%4
810
July1st to 10thDay
14%9%23%32%17%4
796
11th to 20thDay
13%10%27%30%16%4
680
21st to endDay
8%12%25%30%18%7%
515
August1st to 10thDay
10%11%21%36%19%4
447
11th to 20thDay
11%13%30%32%11%3
437
21st to endDay
14%18%31%25%11%2
495
September1st to 10thDay
19%22%29%21%8%1
450
11th to 20thDay
20%18%30%22%8%1
450
21st to endDay
24%25%28%16%7%1
450
October1st to 10thDay
20%21%29%18%9%3
450
11th to 20thDay
18%28%25%18%10%1
288
21st to endDay
15%30%29%19%6%2
297
November1st to 10thDay
14%33%28%16%6%3
239
11th to 20thDay
16%26%36%17%42
180
21st to endDay
17%27%29%13%8%6%
180
December1st to 10thDay
11%25%28%19%11%6%
180
11th to 20thDay
9%28%35%21%5%2
180
21st to endDay
8%16%40%23%12%1
198
January1st to 10thNight
8%27%40%19%5%1
1025
11th to 20thNight
7%24%42%19%6%1
846
21st to endNight
5%25%44%19%6%1
836
February1st to 10thNight
8%24%36%22%8%2
760
11th to 20thNight
6%19%42%23%8%1
744
21st to endNight
8%14%37%27%13%2
628
March1st to 10thNight
6%21%40%23%9%1
722
11th to 20thNight
6%20%44%23%7%1
720
21st to endNight
7%16%40%22%12%2
792
April1st to 10thNight
9%15%36%28%12%1
720
11th to 20thNight
8%13%40%27%11%1
576
21st to endNight
13%15%33%26%13%1
452
May1st to 10thNight
15%10%26%31%15%2
360
11th to 20thNight
13%5%25%34%21%1
354
21st to endNight
21%11%20%25%19%4
389
June1st to 10thNight
24%8%28%26%11%3
360
11th to 20thNight
25%14%22%24%14%2
360
21st to endNight
18%7%19%28%25%4
360
July1st to 10thNight
19%320%29%24%5%
350
11th to 20thNight
16%9%21%30%22%3
348
21st to endNight
10%8%16%38%25%3
394
August1st to 10thNight
13%5%13%39%27%3
358
11th to 20thNight
14%6%18%35%24%3
360
21st to endNight
16%10%25%35%13%1
634
September1st to 10thNight
19%11%28%25%15%2
720
11th to 20thNight
18%12%20%30%15%4
720
21st to endNight
20%18%27%22%10%3
720
October1st to 10thNight
18%13%32%26%11%2
720
11th to 20thNight
17%21%31%24%7%1
720
21st to endNight
15%22%38%18%6%1
792
November1st to 10thNight
13%29%35%17%6%
740
11th to 20thNight
12%26%41%18%3
945
21st to endNight
11%24%41%17%5%2
950
December1st to 10thNight
8%22%42%17%10%1
950
11th to 20thNight
7%24%43%19%7%
959
21st to endNight
5%22%44%20%8%1
1144
Page generated at 2024-02-27 04:30:16. Version ac07

Copyright © 2024 Attilla Danko.


Jasper Athabasca Glacier Clear Sky Chart |Charts Home