Souris
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Souris clear sky chart from 2005-11-06 to 2024-02-05.

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
36%
25183
12%
80562
7%
25105
42%
25105
20%
55632

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
29%
937
8%
4705
6%
926
34%
926
8%
3608
January11th to 20thNight
25%
943
7%
4422
5%
930
29%
930
8%
3506
January21st to endNight
22%
1032
8%
4830
3%
1023
28%
1023
7%
3519
February1st to 10thNight
29%
923
12%
2583
4%
923
36%
923
17%
1920
February11th to 20thNight
34%
830
14%
2255
8%
830
39%
830
21%
1646
February21st to endNight
39%
592
18%
1776
10%
592
45%
592
22%
1231
March1st to 10thNight
34%
720
9%
2160
5%
720
37%
720
16%
1627
March11th to 20thNight
40%
604
18%
2044
13%
604
48%
604
23%
1324
March21st to endNight
39%
594
13%
2098
12%
594
44%
594
17%
1450
April1st to 10thNight
41%
540
18%
1800
13%
540
51%
540
25%
1102
April11th to 20thNight
35%
533
14%
1612
10%
533
42%
533
21%
1124
April21st to endNight
34%
540
13%
1620
8%
540
39%
540
23%
1109
May1st to 10thNight
42%
540
14%
1528
6%
540
45%
540
27%
1009
May11th to 20thNight
42%
531
14%
1327
6%
531
44%
531
28%
919
May21st to endNight
42%
584
10%
1358
5%
582
45%
582
28%
962
June1st to 10thNight
41%
540
7%
1260
3%
540
44%
540
35%
855
June11th to 20thNight
39%
540
5%
1260
4%
540
41%
540
31%
876
June21st to endNight
51%
540
7%
1260
5%
540
54%
540
35%
841
July1st to 10thNight
61%
525
7%
1225
4%
525
63%
525
47%
744
July11th to 20thNight
54%
522
12%
1233
5%
522
58%
522
44%
758
July21st to endNight
64%
591
16%
1488
8%
558
65%
558
47%
831
August1st to 10thNight
59%
537
18%
1424
8%
534
63%
534
44%
813
August11th to 20thNight
60%
534
20%
1561
14%
534
65%
534
36%
908
August21st to endNight
53%
594
23%
1782
20%
594
60%
594
37%
1011
September1st to 10thNight
50%
540
20%
1795
17%
540
59%
540
35%
982
September11th to 20thNight
46%
540
19%
1962
18%
540
54%
540
27%
1114
September21st to endNight
42%
540
19%
1980
18%
540
48%
540
22%
1210
October1st to 10thNight
33%
561
18%
2001
12%
561
41%
561
20%
1303
October11th to 20thNight
35%
889
18%
2329
8%
889
41%
889
25%
1619
October21st to endNight
30%
990
14%
2574
4%
990
35%
990
21%
1871
November1st to 10thNight
28%
925
14%
2408
4%
925
34%
925
19%
1786
November11th to 20thNight
25%
950
12%
2726
5%
950
31%
950
16%
2054
November21st to endNight
25%
950
11%
2850
4%
950
32%
950
16%
2100
December1st to 10thNight
27%
950
9%
2850
3%
950
34%
950
14%
2152
December11th to 20thNight
21%
950
8%
3493
2%
949
27%
949
9%
2720
December21st to endNight
25%
1032
8%
4983
5%
1026
32%
1026
11%
3028

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
11%8%48%7%45%5%6%8%35%
77758
Night
9%9%48%7%45%5%6%7%35%
81078
TransparencyDay
46%8%15%22%8%1
77475
Night
46%8%15%21%9%1
80942
SeeingDay
14%9%31%29%15%3
15093
Night
14%7%32%34%12%1
25234

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
5%15%8%14%10%46%7%9%9%16%
2219
11th to 20thDay
38%5%13%15%8%9%10%6%7%14%
2466
21st to endDay
8%11%7%11%8%46%6%6%7%28%
2794
February1st to 10thDay
9%12%6%12%9%5%6%5%6%7%25%
1472
11th to 20thDay
7%11%5%10%9%5%9%8%5%8%24%
1606
21st to endDay
8%9%5%11%9%5%8%7%5%7%26%
1480
March1st to 10thDay
10%12%6%13%11%5%6%5%6%7%20%
1800
11th to 20thDay
8%11%5%9%8%46%5%6%7%30%
1914
21st to endDay
13%10%5%10%6%45%5%6%8%29%
2256
April1st to 10thDay
10%9%47%6%36%5%5%8%37%
2160
11th to 20thDay
14%12%5%8%6%35%45%6%32%
2298
21st to endDay
15%8%47%6%3446%8%34%
2340
May1st to 10thDay
13%8%36%6%35%45%8%41%
2430
11th to 20thDay
16%8%35%5%35%45%7%39%
2567
21st to endDay
19%8%45%5%35%5%6%7%34%
2918
June1st to 10thDay
13%6%36%5%35%5%6%8%39%
2700
11th to 20thDay
15%7%36%7%45%6%6%8%34%
2700
21st to endDay
12%5%36%5%46%6%6%9%39%
2700
July1st to 10thDay
7%425%5%35%47%10%47%
2700
11th to 20thDay
9%5%25%5%35%6%6%8%46%
2682
21st to endDay
6%3145%345%6%10%52%
2742
August1st to 10thDay
8%6%15%5%35%5%6%9%48%
2507
11th to 20thDay
10%435%436%46%9%47%
2340
21st to endDay
11%5%2442445%8%51%
2574
September1st to 10thDay
11%6%25%43445%7%50%
2162
11th to 20thDay
13%5%25%6%345%5%6%46%
1998
21st to endDay
15%5%25%43345%8%45%
1980
October1st to 10thDay
17%13%45%5%34446%35%
1940
11th to 20thDay
13%9%46%7%3435%7%39%
1630
21st to endDay
14%12%5%10%7%25%5%45%30%
1782
November1st to 10thDay
18%13%6%8%6%34346%28%
1669
11th to 20thDay
10%14%6%11%8%345%5%7%27%
1451
21st to endDay
10%13%5%9%7%46%6%5%6%29%
1330
December1st to 10thDay
7%12%6%15%9%6%7%7%5%5%22%
1330
11th to 20thDay
9%14%6%14%9%6%5%7%6%6%17%
1679
21st to endDay
6%9%410%7%46%8%7%8%31%
2442
January1st to 10thNight
6%14%7%14%9%5%7%6%6%6%21%
4737
11th to 20thNight
6%9%5%13%15%6%8%8%8%5%18%
4424
21st to endNight
7%11%6%14%9%5%6%5%5%6%25%
4873
February1st to 10thNight
8%11%5%10%9%6%6%5%7%7%27%
2583
11th to 20thNight
6%10%5%9%8%48%6%6%6%32%
2254
21st to endNight
7%9%5%9%8%36%6%6%7%35%
1776
March1st to 10thNight
10%12%5%9%8%46%6%5%7%26%
2160
11th to 20thNight
6%9%5%8%7%36%5%6%8%38%
2044
21st to endNight
11%10%5%8%8%345%6%7%34%
2098
April1st to 10thNight
6%7%47%6%46%5%6%8%42%
1800
11th to 20thNight
14%11%46%6%45%5%7%8%32%
1612
21st to endNight
15%7%36%6%5%45%6%7%36%
1620
May1st to 10thNight
13%7%26%5%345%5%7%42%
1528
11th to 20thNight
13%7%35%6%4446%6%42%
1327
21st to endNight
20%6%25%5%35%35%8%39%
1358
June1st to 10thNight
13%5%245%345%6%9%44%
1260
11th to 20thNight
12%5%25%5%45%45%11%41%
1260
21st to endNight
10%425%435%5%7%10%46%
1260
July1st to 10thNight
7%3233235%6%11%53%
1260
11th to 20thNight
7%3234345%5%9%56%
1275
21st to endNight
5%4134235%5%8%59%
1576
August1st to 10thNight
6%42442445%9%57%
1432
11th to 20thNight
6%313436%47%8%54%
1561
21st to endNight
10%425%424347%56%
1782
September1st to 10thNight
10%41442445%8%53%
1795
11th to 20thNight
13%6%2443445%7%49%
1962
21st to endNight
16%7%25%5%34447%43%
1980
October1st to 10thNight
16%10%36%425%346%41%
2001
11th to 20thNight
16%9%35%6%35%447%39%
2329
21st to endNight
12%10%6%7%6%345%5%7%35%
2574
November1st to 10thNight
12%11%5%8%6%45%5%5%6%32%
2408
11th to 20thNight
10%13%6%10%8%35%45%6%30%
2726
21st to endNight
9%12%5%9%8%45%5%5%7%32%
2850
December1st to 10thNight
7%11%5%12%10%5%7%7%5%6%26%
2850
11th to 20thNight
9%15%7%12%9%46%5%6%7%19%
3518
21st to endNight
7%9%48%7%45%8%8%9%32%
5225

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
57%13%14%12%3
2219
11th to 20thDay
62%12%11%11%4
2490
21st to endDay
54%7%11%22%5%
2794
February1st to 10thDay
57%6%13%17%6%
1472
11th to 20thDay
55%8%13%16%8%
1615
21st to endDay
55%8%14%16%7%
1480
March1st to 10thDay
61%9%14%11%5%
1800
11th to 20thDay
50%9%13%20%7%
1916
21st to endDay
52%9%16%18%5%
2256
April1st to 10thDay
45%8%15%21%11%
2160
11th to 20thDay
52%7%12%17%11%1
2298
21st to endDay
48%8%16%19%8%1
2340
May1st to 10thDay
42%7%14%24%11%1
2430
11th to 20thDay
44%6%13%23%13%1
2571
21st to endDay
48%8%13%22%9%1
2918
June1st to 10thDay
42%9%19%20%9%1
2700
11th to 20thDay
47%9%16%19%8%1
2700
21st to endDay
39%11%20%24%6%1
2700
July1st to 10thDay
30%9%21%30%9%1
2626
11th to 20thDay
34%10%18%27%11%1
2601
21st to endDay
26%8%21%33%11%1
2590
August1st to 10thDay
32%9%20%29%10%1
2491
11th to 20thDay
33%9%20%30%7%1
2340
21st to endDay
31%7%16%33%13%1
2574
September1st to 10thDay
34%7%15%30%12%1
2162
11th to 20thDay
38%8%17%26%10%1
1998
21st to endDay
39%7%14%30%11%
1980
October1st to 10thDay
51%6%13%23%7%
1940
11th to 20thDay
44%7%15%26%8%
1630
21st to endDay
55%8%14%17%6%1
1782
November1st to 10thDay
58%7%12%14%7%1
1669
11th to 20thDay
56%8%17%12%6%1
1451
21st to endDay
54%8%16%17%5%
1330
December1st to 10thDay
62%9%13%12%5%
1330
11th to 20thDay
62%10%12%13%3
1680
21st to endDay
44%9%14%20%12%1
2442
January1st to 10thNight
59%10%12%15%4
4737
11th to 20thNight
61%11%12%11%5%
4462
21st to endNight
57%9%11%18%5%
4873
February1st to 10thNight
53%7%13%18%8%1
2583
11th to 20thNight
48%9%13%18%12%1
2255
21st to endNight
46%7%14%23%10%
1776
March1st to 10thNight
53%9%15%16%6%
2160
11th to 20thNight
44%5%16%26%9%1
2044
21st to endNight
48%8%16%20%8%
2098
April1st to 10thNight
37%7%13%25%15%3
1800
11th to 20thNight
49%6%13%19%12%1
1612
21st to endNight
45%7%15%20%10%2
1620
May1st to 10thNight
39%8%14%24%15%
1528
11th to 20thNight
42%7%12%22%14%2
1327
21st to endNight
43%6%14%24%12%
1358
June1st to 10thNight
36%8%20%24%11%2
1260
11th to 20thNight
38%9%17%22%12%2
1260
21st to endNight
32%10%21%30%6%1
1260
July1st to 10thNight
23%8%20%33%14%1
1225
11th to 20thNight
25%9%19%31%15%1
1233
21st to endNight
22%7%18%35%16%1
1488
August1st to 10thNight
24%8%19%34%14%2
1424
11th to 20thNight
26%10%17%35%10%2
1561
21st to endNight
29%6%14%32%17%2
1782
September1st to 10thNight
28%7%15%31%17%2
1795
11th to 20thNight
33%8%17%28%14%1
1962
21st to endNight
41%6%13%29%10%1
1980
October1st to 10thNight
45%6%15%24%9%1
2001
11th to 20thNight
44%7%12%26%11%
2329
21st to endNight
48%8%15%22%7%
2574
November1st to 10thNight
51%7%14%18%7%2
2408
11th to 20thNight
54%8%14%17%6%1
2726
21st to endNight
51%9%16%17%6%
2850
December1st to 10thNight
56%8%16%15%6%
2850
11th to 20thNight
61%8%15%11%41
3516
21st to endNight
42%9%16%18%13%1
5225

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%7%40%27%14%2
270
11th to 20thDay
7%7%41%30%13%1
270
21st to endDay
14%9%36%26%12%3
297
February1st to 10thDay
14%10%38%28%8%1
252
11th to 20thDay
10%5%39%33%11%2
240
21st to endDay
5%5%39%31%18%2
198
March1st to 10thDay
11%11%33%31%11%2
240
11th to 20thDay
11%10%26%34%17%2
240
21st to endDay
15%9%31%30%12%3
342
April1st to 10thDay
15%13%34%28%8%2
420
11th to 20thDay
20%10%31%26%13%1
576
21st to endDay
18%9%32%29%12%1
600
May1st to 10thDay
14%10%28%31%16%1
603
11th to 20thDay
18%7%29%27%16%3
625
21st to endDay
20%10%23%30%16%2
679
June1st to 10thDay
14%9%29%29%13%6%
630
11th to 20thDay
15%9%35%26%12%3
630
21st to endDay
12%8%26%34%16%4
630
July1st to 10thDay
9%5%27%34%19%6%
621
11th to 20thDay
11%7%31%27%19%5%
618
21st to endDay
6%6%24%33%23%8%
684
August1st to 10thDay
10%5%23%35%20%7%
626
11th to 20thDay
9%7%23%30%23%7%
615
21st to endDay
13%7%24%33%20%5%
693
September1st to 10thDay
12%10%35%26%13%4
452
11th to 20thDay
16%9%28%33%11%2
288
21st to endDay
23%9%28%26%11%3
270
October1st to 10thDay
24%14%25%21%14%3
270
11th to 20thDay
15%10%34%28%10%3
270
21st to endDay
22%8%41%20%6%2
297
November1st to 10thDay
24%10%33%20%11%1
270
11th to 20thDay
16%13%38%25%8%
270
21st to endDay
14%13%39%26%7%1
270
December1st to 10thDay
13%10%39%23%13%2
270
11th to 20thDay
15%11%43%24%6%1
270
21st to endDay
11%7%37%29%15%1
297
January1st to 10thNight
12%9%36%33%10%1
950
11th to 20thNight
17%8%35%31%8%1
950
21st to endNight
13%7%40%32%9%
1045
February1st to 10thNight
13%9%34%32%11%1
923
11th to 20thNight
11%6%35%34%11%3
835
21st to endNight
11%5%31%36%15%2
592
March1st to 10thNight
14%8%29%36%11%3
720
11th to 20thNight
8%7%34%36%13%2
604
21st to endNight
15%6%27%35%13%2
594
April1st to 10thNight
9%6%36%37%11%1
540
11th to 20thNight
18%7%32%33%9%
533
21st to endNight
17%5%34%32%10%1
540
May1st to 10thNight
18%6%29%34%12%
540
11th to 20thNight
17%5%31%32%14%
531
21st to endNight
23%6%24%35%12%1
584
June1st to 10thNight
15%5%34%29%16%1
540
11th to 20thNight
14%5%34%35%10%1
540
21st to endNight
11%427%40%17%
540
July1st to 10thNight
8%324%42%22%
525
11th to 20thNight
8%329%41%17%1
522
21st to endNight
7%321%48%18%3
591
August1st to 10thNight
8%325%45%19%1
537
11th to 20thNight
7%5%23%39%23%3
534
21st to endNight
14%425%40%17%1
594
September1st to 10thNight
11%329%35%18%3
540
11th to 20thNight
16%7%28%40%10%
540
21st to endNight
18%8%28%34%12%1
540
October1st to 10thNight
20%7%34%29%10%
561
11th to 20thNight
21%9%28%32%10%
889
21st to endNight
18%8%37%28%8%1
990
November1st to 10thNight
17%11%35%28%8%1
925
11th to 20thNight
16%9%37%27%9%1
950
21st to endNight
15%11%38%28%7%1
950
December1st to 10thNight
11%8%38%29%12%1
950
11th to 20thNight
15%11%34%29%9%2
950
21st to endNight
16%5%34%32%11%2
1045
Page generated at 2024-02-02 04:20:33. Version ac07

Copyright 2024 Attilla Danko


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