Lynch Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lynch Park clear sky chart from 2005-11-06 to 2024-01-13.

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%
22926
17%
74544
10%
22882
45%
22882
21%
48951

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
19%
760
18%
2649
6%
757
34%
757
19%
1674
January11th to 20thNight
18%
732
13%
2560
4%
732
30%
732
14%
1793
January21st to endNight
20%
792
19%
2772
6%
792
36%
792
18%
1770
February1st to 10thNight
19%
720
15%
2281
5%
720
33%
720
16%
1587
February11th to 20thNight
16%
703
19%
2100
5%
700
33%
700
19%
1439
February21st to endNight
23%
592
23%
1776
9%
592
42%
592
22%
1167
March1st to 10thNight
25%
720
20%
2160
10%
720
39%
720
21%
1463
March11th to 20thNight
24%
720
18%
2044
7%
720
35%
720
20%
1432
March21st to endNight
27%
792
21%
2088
7%
792
38%
792
24%
1446
April1st to 10thNight
33%
720
18%
1800
7%
720
39%
720
24%
1293
April11th to 20thNight
38%
674
18%
1738
7%
674
43%
674
27%
1196
April21st to endNight
36%
540
18%
1620
9%
540
43%
540
20%
1118
May1st to 10thNight
37%
540
13%
1620
7%
540
41%
540
18%
1162
May11th to 20thNight
43%
532
15%
1594
11%
532
47%
532
22%
1086
May21st to endNight
50%
393
13%
1555
16%
392
54%
392
17%
1010
June1st to 10thNight
50%
360
13%
1440
16%
360
54%
360
15%
960
June11th to 20thNight
51%
360
13%
1440
19%
360
53%
360
18%
922
June21st to endNight
58%
360
11%
1440
15%
360
61%
360
19%
905
July1st to 10thNight
62%
350
12%
1400
18%
350
64%
350
21%
862
July11th to 20thNight
61%
348
13%
1392
20%
348
62%
348
21%
856
July21st to endNight
65%
394
18%
1486
26%
372
66%
372
24%
884
August1st to 10thNight
66%
513
16%
1577
15%
511
67%
511
29%
975
August11th to 20thNight
59%
532
17%
1596
14%
532
59%
532
23%
1076
August21st to endNight
61%
779
20%
1967
11%
779
64%
779
34%
1283
September1st to 10thNight
58%
720
20%
1822
12%
720
61%
720
34%
1202
September11th to 20thNight
54%
720
24%
1980
16%
720
59%
720
35%
1207
September21st to endNight
52%
720
23%
1980
17%
720
58%
720
32%
1254
October1st to 10thNight
41%
720
17%
1980
10%
720
46%
720
24%
1347
October11th to 20thNight
41%
720
20%
2193
12%
720
51%
720
26%
1390
October21st to endNight
29%
792
15%
2574
7%
792
39%
792
20%
1729
November1st to 10thNight
39%
740
21%
2407
13%
740
50%
740
24%
1495
November11th to 20thNight
28%
760
23%
2470
11%
760
44%
760
23%
1550
November21st to endNight
25%
760
20%
2470
8%
760
40%
760
20%
1561
December1st to 10thNight
18%
760
18%
2598
5%
760
33%
760
17%
1774
December11th to 20thNight
20%
760
17%
3189
3%
758
35%
758
14%
2016
December21st to endNight
19%
828
13%
4786
4%
817
36%
817
10%
3067

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
17%6%35%5%345%5%7%41%
74817
Night
17%7%35%5%3445%7%41%
74913
TransparencyDay
41%7%13%22%15%2
74522
Night
43%7%12%21%14%2
74742
SeeingDay
18%5%23%33%17%3
13953
Night
20%8%29%30%12%1
22934

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 10thDay
15%8%45%5%33446%44%
1517
11th to 20thDay
19%7%46%42336%7%39%
1456
21st to endDay
14%7%25%7%2445%7%43%
1584
February1st to 10thDay
21%8%345%35%5%5%7%34%
1675
11th to 20thDay
14%7%26%5%345%5%7%40%
1748
21st to endDay
17%8%36%5%345%6%7%36%
1480
March1st to 10thDay
17%7%26%425%5%6%8%38%
1797
11th to 20thDay
16%6%35%5%245%6%7%40%
1914
21st to endDay
19%8%25%43345%6%41%
2267
April1st to 10thDay
19%7%35%5%34446%39%
2160
11th to 20thDay
17%6%35%5%45%5%5%7%39%
2169
21st to endDay
21%5%345%35%5%6%6%37%
2340
May1st to 10thDay
24%7%36%5%2445%8%33%
2340
11th to 20thDay
16%7%35%6%3445%7%41%
2309
21st to endDay
15%5%25%5%3445%8%44%
2725
June1st to 10thDay
19%6%246%45%47%7%35%
2520
11th to 20thDay
16%6%35%5%345%5%9%39%
2520
21st to endDay
16%5%25%5%35%6%6%9%37%
2520
July1st to 10thDay
12%5%25%5%345%6%9%43%
2520
11th to 20thDay
11%6%25%5%35%6%7%10%41%
2520
21st to endDay
11%5%35%5%345%7%9%43%
2744
August1st to 10thDay
9%426%5%45%7%7%10%40%
2332
11th to 20thDay
12%6%35%5%45%5%6%9%42%
2304
21st to endDay
13%424435%5%6%8%47%
2386
September1st to 10thDay
13%5%244245%5%7%48%
2138
11th to 20thDay
14%6%23423346%53%
1980
21st to endDay
16%5%2442435%7%47%
1980
October1st to 10thDay
23%6%25%434345%42%
1980
11th to 20thDay
15%6%2442345%7%45%
1764
21st to endDay
20%7%25%5%3345%6%40%
1782
November1st to 10thDay
16%6%34433445%49%
1671
11th to 20thDay
18%7%34323446%46%
1710
21st to endDay
18%7%24434446%44%
1710
December1st to 10thDay
19%8%36%5%34445%41%
1577
11th to 20thDay
22%7%24334436%43%
1906
21st to endDay
22%10%36%5%34445%34%
2772
January1st to 10thNight
16%8%35%5%24446%44%
2649
11th to 20thNight
20%10%35%5%35%5%47%34%
2560
21st to endNight
14%8%36%5%35%45%7%40%
2772
February1st to 10thNight
17%9%36%5%3445%6%37%
2281
11th to 20thNight
16%8%35%5%34446%40%
2098
21st to endNight
19%8%35%433446%43%
1776
March1st to 10thNight
16%8%37%43446%5%41%
2150
11th to 20thNight
17%9%46%5%45%35%6%38%
2044
21st to endNight
18%8%35%5%3434442%
2088
April1st to 10thNight
19%9%26%5%35%46%6%36%
1800
11th to 20thNight
20%6%35%5%3445%6%40%
1738
21st to endNight
21%7%36%5%45%446%36%
1620
May1st to 10thNight
22%9%25%6%3445%5%33%
1620
11th to 20thNight
19%5%35%5%35%5%7%8%35%
1593
21st to endNight
18%7%46%5%33447%39%
1554
June1st to 10thNight
20%8%26%6%34446%37%
1440
11th to 20thNight
19%7%35%42445%10%37%
1440
21st to endNight
16%6%25%5%35%5%7%9%39%
1440
July1st to 10thNight
13%6%36%5%45%5%5%9%40%
1440
11th to 20thNight
11%7%35%6%46%5%7%8%37%
1440
21st to endNight
13%5%35%435%5%6%8%42%
1574
August1st to 10thNight
8%5%25%6%35%5%6%10%44%
1587
11th to 20thNight
11%6%27%6%46%6%7%8%37%
1596
21st to endNight
13%6%2443445%9%46%
1967
September1st to 10thNight
14%5%26%5%3345%8%46%
1822
11th to 20thNight
14%6%24423345%54%
1980
21st to endNight
16%5%25%43345%8%45%
1980
October1st to 10thNight
21%6%35%5%34446%41%
1980
11th to 20thNight
16%6%244345%5%7%44%
2193
21st to endNight
23%7%25%5%24446%38%
2574
November1st to 10thNight
15%5%345%2445%6%47%
2407
11th to 20thNight
17%7%25%423446%46%
2470
21st to endNight
16%6%34434447%45%
2470
December1st to 10thNight
20%8%35%5%24446%38%
2598
11th to 20thNight
19%7%2442446%7%41%
3288
21st to endNight
21%10%36%423446%37%
4884

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
43%6%11%27%12%2
1518
11th to 20thDay
46%7%13%21%10%2
1456
21st to endDay
41%6%16%23%13%1
1584
February1st to 10thDay
48%7%14%18%12%2
1675
11th to 20thDay
43%7%14%22%12%2
1757
21st to endDay
46%6%13%19%13%3
1480
March1st to 10thDay
44%7%13%20%13%4
1800
11th to 20thDay
42%5%12%20%16%4
1914
21st to endDay
44%6%10%19%16%6%
2267
April1st to 10thDay
44%6%10%19%17%4
2160
11th to 20thDay
41%7%11%23%15%4
2169
21st to endDay
43%8%11%19%16%3
2340
May1st to 10thDay
49%6%10%21%13%2
2340
11th to 20thDay
42%7%11%19%17%3
2313
21st to endDay
38%9%15%22%13%2
2725
June1st to 10thDay
46%8%13%21%11%1
2520
11th to 20thDay
40%8%14%19%17%2
2520
21st to endDay
41%11%14%22%11%1
2520
July1st to 10thDay
35%8%15%23%16%2
2450
11th to 20thDay
36%9%15%26%12%2
2445
21st to endDay
34%10%16%23%14%3
2591
August1st to 10thDay
33%12%17%26%12%1
2318
11th to 20thDay
37%10%14%24%14%1
2304
21st to endDay
31%10%13%25%19%2
2386
September1st to 10thDay
34%7%14%25%19%1
2138
11th to 20thDay
33%411%27%22%2
1980
21st to endDay
38%5%11%23%21%2
1980
October1st to 10thDay
42%7%11%22%14%4
1980
11th to 20thDay
36%7%13%29%14%2
1764
21st to endDay
44%6%12%21%14%3
1782
November1st to 10thDay
39%5%14%24%15%2
1671
11th to 20thDay
40%5%11%22%20%2
1710
21st to endDay
42%6%16%22%13%1
1710
December1st to 10thDay
47%5%16%15%16%1
1577
11th to 20thDay
45%6%14%16%15%5%
1906
21st to endDay
52%7%11%20%10%1
2772
January1st to 10thNight
43%6%13%22%14%2
2649
11th to 20thNight
52%6%14%19%7%1
2560
21st to endNight
44%6%12%20%16%2
2772
February1st to 10thNight
48%7%12%19%11%2
2281
11th to 20thNight
47%5%11%21%13%2
2100
21st to endNight
43%6%11%23%14%3
1776
March1st to 10thNight
44%7%9%22%14%4
2160
11th to 20thNight
47%7%10%16%16%4
2045
21st to endNight
46%5%9%17%19%5%
2088
April1st to 10thNight
47%6%11%17%17%3
1800
11th to 20thNight
44%5%10%20%18%3
1738
21st to endNight
49%6%10%17%15%3
1620
May1st to 10thNight
53%6%9%17%13%3
1620
11th to 20thNight
45%8%13%16%14%3
1594
21st to endNight
46%7%13%19%14%1
1555
June1st to 10thNight
49%7%11%20%12%1
1440
11th to 20thNight
44%8%12%20%15%1
1440
21st to endNight
40%10%14%22%13%1
1440
July1st to 10thNight
39%9%14%22%15%1
1400
11th to 20thNight
40%8%15%26%10%1
1392
21st to endNight
37%8%16%27%11%2
1486
August1st to 10thNight
34%9%16%25%14%2
1577
11th to 20thNight
41%11%15%19%13%
1596
21st to endNight
34%8%12%24%20%1
1967
September1st to 10thNight
36%7%12%25%18%1
1822
11th to 20thNight
33%6%10%24%25%2
1980
21st to endNight
36%6%11%24%20%2
1980
October1st to 10thNight
44%7%12%21%13%3
1980
11th to 20thNight
38%8%14%27%12%1
2193
21st to endNight
47%5%13%19%14%2
2574
November1st to 10thNight
38%7%12%22%17%3
2407
11th to 20thNight
40%6%11%23%17%3
2470
21st to endNight
41%6%15%25%12%2
2470
December1st to 10thNight
48%7%12%21%11%1
2598
11th to 20thNight
43%8%15%17%17%1
3288
21st to endNight
49%6%12%23%10%
4884

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
24%11%28%30%6%1
180
11th to 20thDay
16%18%32%26%8%
164
21st to endDay
20%7%40%24%9%
176
February1st to 10thDay
27%11%35%23%3
350
11th to 20thDay
21%9%45%22%3
416
21st to endDay
18%10%35%32%5%
346
March1st to 10thDay
19%11%33%30%7%
420
11th to 20thDay
17%9%35%34%5%
420
21st to endDay
23%7%32%27%8%3
462
April1st to 10thDay
23%8%32%25%10%2
420
11th to 20thDay
20%5%28%36%10%
412
21st to endDay
24%5%23%37%10%1
420
May1st to 10thDay
27%425%32%11%1
423
11th to 20thDay
15%323%41%14%4
447
21st to endDay
18%215%39%22%4
485
June1st to 10thDay
19%414%38%22%3
450
11th to 20thDay
15%317%43%19%3
450
21st to endDay
14%313%42%24%4
450
July1st to 10thDay
16%29%36%30%7%
445
11th to 20thDay
11%312%36%31%7%
444
21st to endDay
10%28%44%34%2
488
August1st to 10thDay
10%211%37%35%5%
446
11th to 20thDay
13%210%37%30%8%
439
21st to endDay
13%39%38%29%8%
495
September1st to 10thDay
16%314%32%26%9%
450
11th to 20thDay
18%319%30%21%8%
450
21st to endDay
19%320%35%18%7%
450
October1st to 10thDay
24%320%29%20%4
450
11th to 20thDay
16%5%26%31%19%3
389
21st to endDay
26%429%29%11%1
396
November1st to 10thDay
15%9%25%33%15%3
365
11th to 20thDay
23%11%32%26%8%1
370
21st to endDay
23%11%28%26%11%1
370
December1st to 10thDay
21%7%40%24%7%
237
11th to 20thDay
19%10%41%26%3
180
21st to endDay
23%11%33%25%6%2
198
January1st to 10thNight
21%14%41%21%4
760
11th to 20thNight
26%13%37%20%3
732
21st to endNight
18%14%42%23%4
792
February1st to 10thNight
23%13%39%23%2
720
11th to 20thNight
20%12%47%17%3
703
21st to endNight
22%11%39%23%5%
592
March1st to 10thNight
21%11%38%25%4
720
11th to 20thNight
21%8%40%24%7%1
720
21st to endNight
22%7%35%26%9%
792
April1st to 10thNight
23%7%32%30%8%
720
11th to 20thNight
21%5%31%33%10%
674
21st to endNight
23%427%35%10%1
540
May1st to 10thNight
24%5%25%33%10%2
540
11th to 20thNight
23%224%37%12%2
532
21st to endNight
22%415%41%18%1
393
June1st to 10thNight
22%315%39%17%4
360
11th to 20thNight
18%318%40%20%1
360
21st to endNight
19%113%47%17%2
360
July1st to 10thNight
14%311%42%26%4
350
11th to 20thNight
12%38%45%28%3
348
21st to endNight
14%29%45%29%1
394
August1st to 10thNight
8%212%46%29%3
513
11th to 20thNight
13%211%44%27%2
532
21st to endNight
14%313%33%31%5%
779
September1st to 10thNight
14%216%39%27%3
720
11th to 20thNight
15%420%32%23%7%
720
21st to endNight
18%220%34%22%4
720
October1st to 10thNight
24%422%29%17%4
720
11th to 20thNight
18%6%29%32%14%2
720
21st to endNight
26%7%31%28%8%1
792
November1st to 10thNight
17%7%32%32%11%2
740
11th to 20thNight
21%11%35%24%8%1
760
21st to endNight
19%16%34%25%6%1
760
December1st to 10thNight
24%12%40%19%5%
760
11th to 20thNight
22%14%38%21%4
760
21st to endNight
24%13%39%22%2
836
Page generated at 2024-01-10 10:16:08. Version ac07

Copyright 2024 Attilla Danko


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