Paulatuk
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Paulatuk clear sky chart from 2005-11-05 to 2017-12-01.

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
44%
13731
5%
48617
5%
13723
45%
13723
10%
38331

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
44%
987
6%
4297
7%
985
45%
985
8%
3284
January16th to endNight
54%
1008
10%
3856
11%
1008
55%
1008
12%
2799
February1st to 15thNight
54%
888
8%
2963
9%
885
55%
885
12%
2322
February16th to endNight
51%
653
8%
2320
9%
653
52%
653
11%
1791
March1st to 15thNight
62%
720
9%
2268
7%
720
63%
720
17%
1673
March16th to endNight
63%
737
5%
2001
5%
737
63%
737
20%
1494
April1st to 15thNight
57%
437
0%
1487
0%
437
57%
437
16%
1057
April16th to endNight
56%
360
0%
1088
0%
360
56%
360
20%
769
May1st to 15thNight
47%
239
0%
618
0%
239
47%
239
18%
480
May16th to endNight0
0%
7300
0%
43
June1st to 15thNight00000
June16th to endNight00000
July1st to 15thNight00000
July16th to endNight
46%
30
0%
175
0%
28
50%
28
7%
114
August1st to 15thNight
47%
299
0%
740
0%
298
46%
298
16%
599
August16th to endNight
41%
382
0%
1264
0%
382
41%
382
11%
1007
September1st to 15thNight
30%
524
0%
1604
0%
524
30%
524
10%
1327
September16th to endNight
26%
716
3%
1974
2%
716
27%
716
10%
1675
October1st to 15thNight
26%
720
3%
2346
1%
720
27%
720
7%
2005
October16th to endNight
33%
914
3%
2928
3%
914
33%
914
7%
2489
November1st to 15thNight
31%
995
4%
3414
4%
995
32%
995
6%
2903
November16th to endNight
36%
1071
3%
4258
3%
1071
37%
1071
5%
3663
December1st to 15thNight
49%
995
5%
4335
7%
995
49%
995
9%
3243
December16th to endNight
45%
1056
4%
4608
4%
1056
46%
1056
8%
3594

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%11%48%7%46%5%6%7%26%
50722
Night
7%12%6%11%10%6%8%7%6%5%16%
48624
TransparencyDay
54%7%17%16%3
50202
Night
63%7%12%13%3
48623
SeeingDay
18%28%25%30%14%
9452
Night
12%212%27%30%14%
13741

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
January16th to endDay
110%25%10%6%10%7%11%8%23%
393
February1st to 15thDay
48%411%9%6%14%11%8%5%15%
906
16th to endDay
38%6%14%9%8%9%9%10%5%15%
1154
March1st to 15thDay
25%5%7%11%8%12%11%10%9%14%
1692
16th to endDay
18%6%11%9%5%10%9%9%7%19%
2222
April1st to 15thDay
49%5%8%9%5%6%8%9%7%23%
2460
16th to endDay
48%49%9%6%6%447%32%
2872
May1st to 15thDay
7%11%6%11%9%45%5%5%7%24%
3332
16th to endDay
9%10%46%5%3445%7%38%
4274
June1st to 15thDay
9%8%5%7%5%35%447%38%
4320
16th to endDay
13%9%35%5%25%5%6%8%33%
4320
July1st to 15thDay
11%7%26%5%35%6%6%9%33%
4320
16th to endDay
19%11%47%6%35%45%6%25%
4127
August1st to 15thDay
18%10%35%6%35%5%5%8%27%
3216
16th to endDay
21%14%5%8%7%35%45%5%18%
2936
September1st to 15thDay
20%20%310%6%3443417%
2354
16th to endDay
24%20%5%8%6%2433316%
1984
October1st to 15thDay
14%21%9%11%6%335%4415%
1614
16th to endDay
9%22%8%13%7%45%5%4413%
1284
November1st to 15thDay
6%19%10%12%12%6%8%32314%
773
16th to endDay
111%7%17%17%12%8%5%2311%
169
January1st to 15thNight
5%10%6%11%12%7%8%7%9%5%14%
4297
16th to endNight
39%5%9%9%7%9%10%10%7%18%
3856
February1st to 15thNight
28%5%10%11%7%14%11%7%7%14%
2957
16th to endNight
27%6%13%12%6%10%9%7%5%17%
2320
March1st to 15thNight
16%38%12%8%11%11%11%9%14%
2268
16th to endNight
18%5%6%10%7%10%9%8%9%22%
1997
April1st to 15thNight
48%5%8%10%5%7%7%7%5%27%
1487
16th to endNight
311%5%9%8%37%45%8%31%
1088
May1st to 15thNight
9%8%6%14%7%36%7%5%6%24%
617
16th to endNight
10%13%28%13%45%6%9%24%
73
July16th to endNight
16%8%5%7%5%447%47%26%
190
August1st to 15thNight
20%13%27%5%46%448%22%
743
16th to endNight
25%15%36%5%25%44422%
1264
September1st to 15thNight
20%21%38%7%3334419%
1604
16th to endNight
27%20%46%6%2422319%
1974
October1st to 15thNight
14%22%10%12%7%4433313%
2346
16th to endNight
10%22%9%12%8%45%5%4313%
2928
November1st to 15thNight
6%16%8%15%12%5%5%34315%
3414
16th to endNight
313%8%16%16%7%8%5%3312%
4258
December1st to 15thNight
5%9%5%10%10%6%9%11%9%5%15%
4335
16th to endNight
5%11%7%11%10%6%9%7%7%6%15%
4608

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
January16th to endDay
47%7%10%23%9%
393
February1st to 15thDay
58%9%10%15%6%
906
16th to endDay
57%9%10%18%31
1154
March1st to 15thDay
52%9%14%16%6%
1692
16th to endDay
52%8%11%21%5%
2222
April1st to 15thDay
52%6%13%16%9%
2460
16th to endDay
51%413%24%5%
2872
May1st to 15thDay
58%6%17%15%1
3332
16th to endDay
45%5%17%24%6%
4279
June1st to 15thDay
43%7%21%24%3
4320
16th to endDay
46%8%21%22%2
4320
July1st to 15thDay
46%9%20%21%2
4071
16th to endDay
55%9%19%13%1
3873
August1st to 15thDay
54%8%22%12%1
3194
16th to endDay
67%7%16%6%
2936
September1st to 15thDay
70%5%14%9%
2354
16th to endDay
73%5%13%6%
1984
October1st to 15thDay
71%6%14%7%
1614
16th to endDay
69%8%14%7%
1284
November1st to 15thDay
73%7%7%8%2
773
16th to endDay
73%8%11%5%1
169
January1st to 15thNight
63%5%13%14%1
4297
16th to endNight
54%8%10%19%6%
3856
February1st to 15thNight
58%9%11%12%7%
2969
16th to endNight
59%8%10%16%4
2320
March1st to 15thNight
51%9%14%16%7%
2268
16th to endNight
49%9%10%21%8%
2001
April1st to 15thNight
53%5%13%14%11%
1487
16th to endNight
51%411%25%6%
1088
May1st to 15thNight
59%316%17%2
618
16th to endNight
53%5%21%16%2
73
July16th to endNight
53%6%18%21%
175
August1st to 15thNight
58%9%17%12%2
740
16th to endNight
64%5%18%9%1
1264
September1st to 15thNight
68%5%14%10%
1604
16th to endNight
70%5%12%10%1
1974
October1st to 15thNight
74%5%11%8%
2346
16th to endNight
70%7%13%7%
2928
November1st to 15thNight
73%6%10%7%2
3414
16th to endNight
73%7%9%7%1
4258
December1st to 15thNight
57%9%16%15%
4335
16th to endNight
64%7%13%13%1
4608

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
January16th to endDay
5%5%17%52%17%
17
February1st to 15thDay
6%5%6%27%20%33%
59
16th to endDay
1422%34%37%
72
March1st to 15thDay
3111%34%30%18%
249
16th to endDay
5%17%23%36%25%
288
April1st to 15thDay
5%16%24%36%26%
299
16th to endDay
7%113%26%33%17%
577
May1st to 15thDay
12%310%28%30%15%
648
16th to endDay
12%210%24%35%13%
1007
June1st to 15thDay
14%29%26%34%13%
1035
16th to endDay
16%27%33%30%9%
1035
July1st to 15thDay
17%17%24%36%12%
985
16th to endDay
29%25%24%27%10%
919
August1st to 15thDay
26%16%20%31%13%
672
16th to endDay
35%27%18%23%13%
574
September1st to 15thDay
36%310%22%17%9%
315
16th to endDay
34%313%20%17%11%
315
October1st to 15thDay
16%211%27%30%12%
210
16th to endDay
13%310%23%32%16%
96
November1st to 15thDay
20%317%35%20%3
80
January1st to 15thNight
6%317%27%33%10%
990
16th to endNight
6%313%31%32%12%
1008
February1st to 15thNight
5%312%31%30%16%
893
16th to endNight
5%211%31%26%22%
653
March1st to 15thNight
311%33%37%13%
720
16th to endNight
319%26%37%21%
738
April1st to 15thNight
6%26%23%40%20%
437
16th to endNight
6%112%32%34%12%
360
May1st to 15thNight
13%9%31%33%11%
240
July16th to endNight
30%3336%23%3
30
August1st to 15thNight
28%29%17%34%8%
299
16th to endNight
35%27%19%25%9%
382
September1st to 15thNight
35%113%21%21%5%
524
16th to endNight
34%415%18%17%9%
716
October1st to 15thNight
24%313%22%28%7%
720
16th to endNight
21%29%26%28%11%
914
November1st to 15thNight
13%313%31%26%12%
995
16th to endNight
6%111%28%33%18%
1071
December1st to 15thNight
7%314%26%31%17%
995
16th to endNight
7%213%27%29%19%
1056
Page generated at 2017-12-02 07:14:26. Version ac04

Copyright 2017 A. Danko


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