Laonil Lake
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Laonil Lake clear sky chart from 2005-11-05 to 2017-09-22.

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
33%
15611
9%
46742
5%
15582
37%
15582
17%
34503

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
25%
896
10%
2864
5%
895
30%
895
12%
2195
January16th to endNight
22%
960
10%
2898
5%
960
27%
960
12%
2289
February1st to 15thNight
31%
873
13%
2463
5%
872
39%
872
20%
1762
February16th to endNight
37%
663
11%
2035
7%
663
41%
663
16%
1514
March1st to 15thNight
35%
720
14%
2160
9%
720
41%
720
18%
1564
March16th to endNight
36%
631
16%
2014
12%
631
43%
631
20%
1375
April1st to 15thNight
36%
539
13%
1762
9%
539
42%
539
21%
1184
April16th to endNight
38%
540
14%
1467
7%
540
42%
540
25%
1017
May1st to 15thNight
36%
539
4%
1358
3%
539
38%
539
26%
957
May16th to endNight
43%
415
0%
1163
0%
414
43%
414
23%
801
June1st to 15thNight
41%
360
0%
1080
0%
360
41%
360
22%
733
June16th to endNight
43%
360
0%
1080
0%
360
43%
360
20%
775
July1st to 15thNight
48%
340
0%
1020
0%
340
48%
340
25%
672
July16th to endNight
55%
391
0%
1104
0%
368
56%
368
28%
696
August1st to 15thNight
54%
539
5%
1432
4%
536
56%
536
32%
917
August16th to endNight
45%
573
11%
1607
6%
573
48%
573
25%
1101
September1st to 15thNight
44%
540
10%
1800
9%
540
48%
540
23%
1163
September16th to endNight
36%
516
15%
1855
12%
516
44%
516
21%
1201
October1st to 15thNight
26%
701
10%
2021
4%
701
32%
701
16%
1508
October16th to endNight
20%
880
8%
2310
2%
880
23%
880
12%
1870
November1st to 15thNight
21%
875
9%
2567
3%
875
25%
875
10%
2094
November16th to endNight
22%
900
4%
2730
2%
900
26%
900
9%
2294
December1st to 15thNight
25%
900
6%
2880
3%
900
28%
900
8%
2381
December16th to endNight
28%
960
9%
3072
6%
960
32%
960
10%
2440

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
14%10%47%6%35%5%5%7%29%
48204
Night
12%11%48%7%46%5%5%7%26%
46872
TransparencyDay
52%5%14%19%7%
47837
Night
55%414%18%6%
46744
SeeingDay
19%9%29%25%12%3
6303
Night
18%7%28%29%13%2
15623

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 15thDay
10%14%6%8%6%5%8%7%8%5%19%
1074
16th to endDay
11%16%5%11%9%26%5%47%21%
1325
February1st to 15thDay
5%8%6%9%9%6%8%7%9%6%23%
1400
16th to endDay
6%11%7%10%8%5%7%5%5%5%25%
1446
March1st to 15thDay
10%14%48%7%34446%31%
1800
16th to endDay
10%10%47%5%35%5%5%7%33%
2209
April1st to 15thDay
11%9%47%5%35%46%6%34%
2186
16th to endDay
9%9%47%6%345%6%7%34%
2493
May1st to 15thDay
14%8%36%6%35%447%34%
2592
16th to endDay
17%7%25%424347%39%
2950
June1st to 15thDay
17%7%36%6%35%5%5%6%30%
2880
16th to endDay
22%7%36%6%35%5%5%7%25%
2880
July1st to 15thDay
16%5%25%6%36%5%5%8%33%
2880
16th to endDay
13%6%26%7%46%6%6%7%32%
2990
August1st to 15thDay
12%6%26%6%35%5%5%7%38%
2520
16th to endDay
15%6%36%445%5%6%8%32%
2591
September1st to 15thDay
15%8%26%5%345%47%34%
2160
16th to endDay
19%12%35%5%34446%29%
1915
October1st to 15thDay
22%15%5%7%5%23346%23%
1598
16th to endDay
18%23%6%10%5%2334317%
1562
November1st to 15thDay
19%16%7%12%7%2323419%
1291
16th to endDay
11%10%8%15%11%49%45%5%12%
1230
December1st to 15thDay
8%13%7%12%13%36%6%7%7%13%
1080
16th to endDay
11%11%5%11%12%5%6%6%7%6%14%
1152
January1st to 15thNight
9%13%5%9%9%5%6%6%7%8%17%
2864
16th to endNight
12%12%6%10%8%47%6%6%6%18%
2898
February1st to 15thNight
7%9%38%6%48%6%7%9%26%
2453
16th to endNight
6%10%5%9%7%5%9%8%6%6%25%
2035
March1st to 15thNight
9%12%6%6%7%45%5%5%6%28%
2160
16th to endNight
10%11%47%6%245%5%6%34%
2011
April1st to 15thNight
11%10%47%44445%7%34%
1762
16th to endNight
9%10%47%7%34345%38%
1467
May1st to 15thNight
13%8%35%6%35%5%5%8%34%
1358
16th to endNight
15%6%25%5%25%6%6%6%36%
1163
June1st to 15thNight
14%7%16%6%46%438%34%
1080
16th to endNight
18%9%36%425%5%5%6%32%
1080
July1st to 15thNight
15%5%25%435%46%8%36%
1080
16th to endNight
12%4245%35%6%6%10%38%
1179
August1st to 15thNight
11%32443446%10%43%
1440
16th to endNight
12%6%26%5%36%5%7%8%35%
1607
September1st to 15thNight
13%6%25%5%345%5%7%39%
1800
16th to endNight
16%8%34335%5%5%7%36%
1855
October1st to 15thNight
21%14%36%423446%29%
2021
16th to endNight
17%19%5%8%6%24345%21%
2310
November1st to 15thNight
17%17%7%9%8%4334419%
2567
16th to endNight
10%13%7%11%11%6%10%5%4414%
2730
December1st to 15thNight
9%13%7%12%11%5%8%6%7%5%11%
2880
16th to endNight
8%13%6%12%10%5%6%6%6%7%15%
3072

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
60%5%12%16%4
1074
16th to endDay
62%310%16%7%
1325
February1st to 15thDay
54%414%18%7%
1400
16th to endDay
58%313%17%6%
1446
March1st to 15thDay
53%413%21%7%1
1800
16th to endDay
46%413%25%8%
2210
April1st to 15thDay
46%5%13%23%10%
2186
16th to endDay
45%413%24%10%
2493
May1st to 15thDay
49%49%24%12%1
2592
16th to endDay
44%410%23%16%
2955
June1st to 15thDay
52%410%21%10%
2880
16th to endDay
56%5%12%17%6%
2880
July1st to 15thDay
46%5%17%22%7%
2711
16th to endDay
48%6%19%21%3
2802
August1st to 15thDay
43%6%21%24%4
2504
16th to endDay
46%7%25%17%3
2591
September1st to 15thDay
48%5%20%18%6%
2160
16th to endDay
53%5%20%17%3
1915
October1st to 15thDay
61%414%16%3
1598
16th to endDay
71%311%11%1
1562
November1st to 15thDay
70%210%12%4
1291
16th to endDay
71%411%11%
1230
December1st to 15thDay
65%6%13%11%3
1080
16th to endDay
65%5%11%15%1
1152
January1st to 15thNight
60%5%14%16%3
2864
16th to endNight
63%411%14%5%
2898
February1st to 15thNight
50%415%20%8%
2464
16th to endNight
56%5%13%17%6%
2035
March1st to 15thNight
53%412%19%7%1
2160
16th to endNight
48%412%23%9%1
2014
April1st to 15thNight
48%412%20%12%2
1762
16th to endNight
47%39%25%12%1
1467
May1st to 15thNight
46%49%24%12%2
1359
16th to endNight
44%6%8%23%14%1
1163
June1st to 15thNight
46%5%12%21%13%
1080
16th to endNight
50%5%14%22%5%1
1080
July1st to 15thNight
44%316%26%8%
1020
16th to endNight
38%6%22%28%4
1104
August1st to 15thNight
35%7%23%26%6%
1432
16th to endNight
43%7%20%25%3
1607
September1st to 15thNight
43%5%20%22%7%1
1800
16th to endNight
45%418%24%5%
1855
October1st to 15thNight
56%415%19%4
2021
16th to endNight
65%314%14%1
2310
November1st to 15thNight
68%411%13%3
2567
16th to endNight
70%413%8%2
2730
December1st to 15thNight
69%5%11%11%2
2880
16th to endNight
65%412%14%2
3072

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
5%10%46%23%15%
60
16th to endDay
15%5%43%26%8%
71
February1st to 15thDay
412%50%24%5%3
90
16th to endDay
17%11%29%24%12%4
81
March1st to 15thDay
23%15%30%24%6%
90
16th to endDay
15%11%34%24%12%1
249
April1st to 15thDay
21%12%36%21%7%
305
16th to endDay
13%8%33%28%15%2
450
May1st to 15thDay
22%10%29%23%11%3
468
16th to endDay
19%10%23%29%15%2
517
June1st to 15thDay
21%10%27%24%11%4
495
16th to endDay
24%7%26%24%12%4
495
July1st to 15thDay
19%8%25%28%16%3
475
16th to endDay
15%6%28%26%17%5%
515
August1st to 15thDay
13%6%23%25%21%10%
493
16th to endDay
17%8%29%30%10%3
502
September1st to 15thDay
23%15%34%19%7%
315
16th to endDay
25%10%34%23%42
147
October1st to 15thDay
36%6%35%16%31
90
16th to endDay
41%9%29%13%5%1
96
November1st to 15thDay
16%16%38%14%12%1
90
16th to endDay
20%9%29%32%5%2
85
December1st to 15thDay
20%5%30%33%5%6%
60
16th to endDay
46%46%32%44
64
January1st to 15thNight
16%9%31%30%10%1
900
16th to endNight
18%10%35%25%8%1
960
February1st to 15thNight
11%7%37%29%11%2
880
16th to endNight
11%7%28%31%17%3
663
March1st to 15thNight
14%8%28%31%14%1
720
16th to endNight
17%6%29%28%16%2
631
April1st to 15thNight
17%5%30%32%12%1
539
16th to endNight
16%6%27%32%15%1
540
May1st to 15thNight
18%7%30%29%12%1
540
16th to endNight
18%7%26%33%13%
415
June1st to 15thNight
17%428%31%18%1
360
16th to endNight
21%321%34%17%1
360
July1st to 15thNight
18%5%20%35%20%
340
16th to endNight
13%317%38%21%5%
391
August1st to 15thNight
13%420%32%23%5%
539
16th to endNight
15%5%27%34%15%1
573
September1st to 15thNight
17%5%25%34%15%1
540
16th to endNight
21%6%31%30%10%
516
October1st to 15thNight
30%6%27%25%7%1
701
16th to endNight
30%9%28%23%7%1
880
November1st to 15thNight
26%9%29%23%9%1
875
16th to endNight
17%10%32%29%7%1
900
December1st to 15thNight
14%9%32%31%10%2
900
16th to endNight
14%9%26%29%17%3
960
Page generated at 2017-09-23 04:43:46. Version ac04

Copyright 2017 A. Danko


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