Kirkland Lake
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Kirkland Lake clear sky chart from 2005-11-05 to 2017-09-20.

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%
15100
10%
46783
6%
15069
30%
15069
13%
35521

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%
899
6%
2685
3%
895
16%
895
6%
2286
January16th to endNight
22%
889
8%
2695
4%
889
26%
889
8%
2242
February1st to 15thNight
23%
704
9%
2287
5%
701
29%
701
11%
1787
February16th to endNight
18%
631
8%
2048
3%
631
24%
631
9%
1631
March1st to 15thNight
23%
720
13%
2013
8%
720
28%
720
13%
1566
March16th to endNight
27%
768
17%
2112
9%
768
33%
768
19%
1535
April1st to 15thNight
25%
665
14%
1758
6%
665
30%
665
17%
1311
April16th to endNight
28%
540
17%
1620
9%
540
35%
540
21%
1117
May1st to 15thNight
32%
405
14%
1485
13%
405
40%
405
17%
1003
May16th to endNight
33%
374
10%
1420
8%
374
41%
374
18%
946
June1st to 15thNight
34%
360
8%
1260
7%
360
37%
360
19%
847
June16th to endNight
40%
360
7%
1260
5%
360
42%
360
23%
783
July1st to 15thNight
40%
340
9%
1190
8%
340
43%
340
23%
740
July16th to endNight
46%
376
13%
1290
15%
354
50%
354
23%
804
August1st to 15thNight
41%
530
11%
1601
7%
528
46%
528
22%
1094
August16th to endNight
41%
573
16%
1719
10%
573
45%
573
25%
1119
September1st to 15thNight
37%
717
12%
1808
5%
717
40%
717
25%
1270
September16th to endNight
40%
677
16%
1888
11%
677
42%
677
24%
1279
October1st to 15thNight
22%
660
13%
1980
9%
660
29%
660
15%
1502
October16th to endNight
19%
704
8%
2184
6%
704
22%
704
9%
1796
November1st to 15thNight
17%
700
10%
2452
7%
700
24%
700
9%
1942
November16th to endNight
14%
720
7%
2520
4%
720
17%
720
7%
2113
December1st to 15thNight
14%
828
4%
2628
0%
828
18%
828
6%
2264
December16th to endNight
14%
960
6%
2880
3%
960
16%
960
5%
2544

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
20%11%47%6%3445%6%25%
48077
Night
18%12%5%8%6%34445%25%
46935
TransparencyDay
59%310%17%7%
47747
Night
60%310%16%7%
46783
SeeingDay
26%10%29%21%9%2
5936
Night
25%9%29%24%9%1
15102

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%14%9%11%7%26%36%412%
1253
16th to endDay
15%18%6%9%7%35%5%7%6%14%
1525
February1st to 15thDay
7%16%7%9%8%6%8%6%46%17%
1575
16th to endDay
13%18%7%10%7%44425%21%
1422
March1st to 15thDay
16%12%5%8%7%3445%5%25%
1935
16th to endDay
13%12%48%6%35%435%32%
2112
April1st to 15thDay
22%13%47%5%23235%27%
2202
16th to endDay
20%11%36%5%24345%32%
2340
May1st to 15thDay
20%10%37%5%35%45%6%27%
2466
16th to endDay
23%8%36%5%23446%30%
2693
June1st to 15thDay
21%8%36%5%245%6%7%28%
2700
16th to endDay
19%6%35%6%36%5%6%8%27%
2700
July1st to 15thDay
18%7%26%5%345%5%8%30%
2700
16th to endDay
17%6%36%6%35%5%5%7%30%
2790
August1st to 15thDay
19%7%37%7%45%5%5%7%25%
2346
16th to endDay
20%7%36%5%35%5%6%7%28%
2474
September1st to 15thDay
23%7%26%6%2445%6%30%
2148
16th to endDay
24%8%35%5%3335%6%31%
1840
October1st to 15thDay
25%13%37%5%3324424%
1650
16th to endDay
31%20%5%6%7%3333311%
1687
November1st to 15thDay
24%19%6%6%5%2423418%
1406
16th to endDay
24%18%8%12%7%3323312%
1440
December1st to 15thDay
20%17%8%12%7%2344412%
1329
16th to endDay
20%19%9%12%8%4433410%
1344
January1st to 15thNight
19%18%7%11%9%345%4411%
2685
16th to endNight
14%16%6%11%9%5%6%5%45%14%
2695
February1st to 15thNight
11%13%7%9%10%38%447%19%
2285
16th to endNight
14%16%6%12%7%35%445%18%
2048
March1st to 15thNight
15%13%6%10%7%34345%24%
2001
16th to endNight
13%11%38%7%44445%33%
2112
April1st to 15thNight
22%12%47%423245%29%
1758
16th to endNight
20%9%24434445%36%
1620
May1st to 15thNight
18%9%35%445%445%35%
1485
16th to endNight
17%6%36%5%345%47%34%
1418
June1st to 15thNight
21%8%343245%47%33%
1260
16th to endNight
13%6%25%5%345%5%8%38%
1260
July1st to 15thNight
14%5%35%4345%6%7%38%
1260
16th to endNight
15%4245%25%447%41%
1378
August1st to 15thNight
14%5%25%7%45%7%5%7%33%
1611
16th to endNight
17%5%25%6%23347%40%
1719
September1st to 15thNight
17%8%35%433447%37%
1808
16th to endNight
19%7%24324346%39%
1888
October1st to 15thNight
23%12%47%423436%26%
1980
16th to endNight
28%17%47%5%33335%17%
2184
November1st to 15thNight
21%14%7%8%6%3444420%
2452
16th to endNight
26%17%7%9%6%2323415%
2520
December1st to 15thNight
19%19%7%11%8%35%34411%
2628
16th to endNight
20%20%8%10%8%5%5%4339%
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
73%26%14%3
1254
16th to endDay
67%27%13%8%
1525
February1st to 15thDay
64%410%13%6%
1577
16th to endDay
67%25%17%7%
1422
March1st to 15thDay
60%48%16%10%
1946
16th to endDay
54%27%21%10%2
2112
April1st to 15thDay
59%36%17%11%1
2202
16th to endDay
54%210%18%13%1
2340
May1st to 15thDay
56%38%17%12%1
2466
16th to endDay
55%311%20%9%
2697
June1st to 15thDay
53%312%21%8%
2700
16th to endDay
52%412%20%8%
2700
July1st to 15thDay
48%414%23%7%
2541
16th to endDay
52%5%12%25%4
2615
August1st to 15thDay
56%5%15%18%3
2332
16th to endDay
54%415%19%5%
2474
September1st to 15thDay
54%415%18%7%
2148
16th to endDay
53%314%24%3
1840
October1st to 15thDay
63%311%14%7%
1650
16th to endDay
78%45%7%3
1687
November1st to 15thDay
69%212%10%4
1406
16th to endDay
78%37%8%2
1440
December1st to 15thDay
74%39%8%3
1329
16th to endDay
78%35%8%3
1344
January1st to 15thNight
74%38%10%2
2685
16th to endNight
72%36%12%4
2695
February1st to 15thNight
64%310%14%6%
2287
16th to endNight
68%28%13%6%
2048
March1st to 15thNight
62%27%14%10%1
2013
16th to endNight
54%27%18%13%2
2112
April1st to 15thNight
57%26%18%13%2
1758
16th to endNight
50%27%19%18%1
1620
May1st to 15thNight
51%39%19%14%1
1485
16th to endNight
48%5%14%18%11%2
1420
June1st to 15thNight
50%310%22%10%2
1260
16th to endNight
42%415%24%11%1
1260
July1st to 15thNight
40%5%15%26%10%
1190
16th to endNight
43%415%29%7%
1290
August1st to 15thNight
46%5%17%25%5%
1601
16th to endNight
43%418%27%6%
1719
September1st to 15thNight
45%5%20%20%7%1
1808
16th to endNight
45%415%28%5%
1888
October1st to 15thNight
60%311%16%7%
1980
16th to endNight
70%39%12%3
2184
November1st to 15thNight
67%311%13%3
2452
16th to endNight
73%39%9%3
2520
December1st to 15thNight
75%38%10%2
2628
16th to endNight
79%35%8%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%15%36%13%5%
60
16th to endDay
45%7%27%14%4
83
February1st to 15thDay
26%11%35%26%
90
16th to endDay
35%18%34%9%1
81
March1st to 15thDay
25%12%36%19%5%
236
16th to endDay
22%14%35%18%7%2
288
April1st to 15thDay
26%17%25%22%6%2
270
16th to endDay
28%14%29%15%7%4
270
May1st to 15thDay
31%9%25%19%10%3
288
16th to endDay
29%9%32%19%6%2
406
June1st to 15thDay
26%11%29%21%9%1
495
16th to endDay
20%11%29%28%9%1
495
July1st to 15thDay
20%8%31%27%9%1
475
16th to endDay
19%7%30%26%12%3
461
August1st to 15thDay
22%5%25%25%13%7%
313
16th to endDay
27%6%24%24%12%5%
332
September1st to 15thDay
21%5%31%21%15%4
315
16th to endDay
27%8%27%22%10%3
270
October1st to 15thDay
30%9%29%20%8%1
255
16th to endDay
35%15%26%16%32
209
November1st to 15thDay
36%13%38%10%1
60
16th to endDay
48%13%31%311
60
December1st to 15thDay
30%15%41%6%5%1
60
16th to endDay
35%20%34%6%3
64
January1st to 15thNight
27%14%32%17%7%
900
16th to endNight
21%9%31%25%9%1
889
February1st to 15thNight
18%9%36%27%8%
704
16th to endNight
23%11%34%22%7%
631
March1st to 15thNight
23%17%28%22%6%
720
16th to endNight
19%12%34%23%8%1
768
April1st to 15thNight
27%12%28%23%5%
665
16th to endNight
25%10%32%22%8%1
540
May1st to 15thNight
24%8%28%27%10%
405
16th to endNight
20%8%30%32%6%1
375
June1st to 15thNight
24%7%26%27%12%
360
16th to endNight
18%330%33%12%1
360
July1st to 15thNight
17%5%31%32%11%1
340
16th to endNight
16%325%37%14%1
376
August1st to 15thNight
16%327%28%21%2
530
16th to endNight
19%425%31%16%1
573
September1st to 15thNight
22%7%26%25%15%2
717
16th to endNight
24%5%25%27%14%2
677
October1st to 15thNight
31%9%29%20%8%1
660
16th to endNight
36%8%26%19%6%1
704
November1st to 15thNight
29%13%30%19%6%1
700
16th to endNight
35%11%28%19%4
720
December1st to 15thNight
29%11%32%19%5%
828
16th to endNight
30%12%27%19%7%1
960
Page generated at 2017-09-21 07:18:17. Version ac04

Copyright 2017 A. Danko


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