Franklinton
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Franklinton clear sky chart from 2005-11-06 to 2024-01-12.

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
41%
24335
22%
74717
12%
24285
50%
24285
25%
46705

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
23%
757
23%
2459
9%
757
40%
757
20%
1496
January11th to 20thNight
24%
725
23%
2354
9%
725
41%
725
19%
1511
January21st to endNight
23%
792
28%
2574
11%
792
45%
792
24%
1517
February1st to 10thNight
24%
720
19%
2340
9%
720
38%
720
22%
1459
February11th to 20thNight
14%
700
19%
2241
5%
699
31%
699
17%
1438
February21st to endNight
22%
592
28%
1673
11%
592
40%
592
24%
1074
March1st to 10thNight
26%
720
26%
1980
11%
720
41%
720
29%
1210
March11th to 20thNight
25%
720
20%
1980
8%
720
37%
720
22%
1326
March21st to endNight
24%
792
20%
2178
8%
792
35%
792
24%
1429
April1st to 10thNight
29%
720
24%
1846
8%
720
40%
720
29%
1179
April11th to 20thNight
32%
711
25%
1775
9%
711
42%
711
34%
1133
April21st to endNight
34%
720
23%
1800
8%
720
42%
720
32%
1173
May1st to 10thNight
34%
604
19%
1684
8%
604
41%
604
27%
1069
May11th to 20thNight
42%
531
16%
1593
11%
531
46%
531
24%
1058
May21st to endNight
57%
582
16%
1744
12%
582
59%
582
28%
1117
June1st to 10thNight
56%
460
16%
1540
15%
460
59%
460
26%
961
June11th to 20thNight
55%
379
17%
1459
17%
379
59%
379
22%
891
June21st to endNight
65%
540
16%
1620
13%
540
68%
540
26%
1065
July1st to 10thNight
67%
525
14%
1575
11%
525
68%
525
28%
1027
July11th to 20thNight
72%
522
15%
1566
13%
522
72%
522
30%
1001
July21st to endNight
62%
591
16%
1672
12%
558
65%
558
27%
1107
August1st to 10thNight
61%
537
13%
1600
11%
534
61%
534
24%
1103
August11th to 20thNight
61%
603
17%
1667
12%
603
63%
603
25%
1155
August21st to endNight
64%
792
17%
1980
11%
792
65%
792
30%
1355
September1st to 10thNight
67%
720
22%
1800
16%
720
69%
720
34%
1196
September11th to 20thNight
58%
720
25%
1876
19%
720
60%
720
30%
1248
September21st to endNight
43%
720
17%
2038
11%
720
49%
720
22%
1434
October1st to 10thNight
51%
720
23%
2160
20%
720
59%
720
31%
1330
October11th to 20thNight
44%
720
28%
2160
21%
720
57%
720
30%
1280
October21st to endNight
45%
792
31%
2376
21%
792
60%
792
33%
1350
November1st to 10thNight
41%
740
27%
2221
18%
740
53%
740
32%
1317
November11th to 20thNight
38%
760
28%
2294
16%
760
52%
760
29%
1359
November21st to endNight
40%
760
26%
2645
18%
760
54%
760
26%
1484
December1st to 10thNight
28%
760
21%
2660
11%
760
42%
760
18%
1690
December11th to 20thNight
33%
760
24%
3177
15%
758
48%
758
21%
1795
December21st to endNight
29%
828
17%
4410
11%
817
44%
817
14%
2368

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
13%5%25%5%35%5%6%8%43%
74493
Night
14%6%25%5%3445%7%45%
75183
TransparencyDay
38%6%12%22%17%4
74214
Night
38%6%11%21%19%5%
74981
SeeingDay
18%11%26%24%16%5%
14144
Night
17%10%26%30%16%2
24351

By Month

Percentage Cloud Cover SE (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
16%7%35%43335%5%47%
1706
11th to 20thDay
18%6%345%245%5%6%43%
1629
21st to endDay
17%6%24423346%48%
1782
February1st to 10thDay
14%6%26%5%3446%9%41%
1620
11th to 20thDay
21%6%24424345%45%
1605
21st to endDay
18%7%36%5%2435%6%41%
1578
March1st to 10thDay
15%6%23424446%50%
1980
11th to 20thDay
16%6%35%4235%6%9%41%
1980
21st to endDay
17%7%36%436%447%39%
2178
April1st to 10thDay
11%42332445%7%54%
2114
11th to 20thDay
11%425%5%345%6%9%48%
2134
21st to endDay
15%6%24435%5%6%6%45%
2160
May1st to 10thDay
12%5%345%45%5%7%9%41%
2290
11th to 20thDay
15%5%36%6%45%6%5%8%37%
2301
21st to endDay
12%6%25%6%35%7%6%9%39%
2531
June1st to 10thDay
10%5%35%5%46%5%7%9%40%
2405
11th to 20thDay
9%5%25%5%446%7%10%44%
2484
21st to endDay
8%5%35%6%47%6%7%11%37%
2340
July1st to 10thDay
8%5%26%6%47%7%9%11%34%
2340
11th to 20thDay
7%436%6%46%7%10%13%33%
2340
21st to endDay
7%5%27%6%5%7%7%9%12%34%
2547
August1st to 10thDay
11%6%37%6%36%8%8%10%33%
2327
11th to 20thDay
11%7%36%7%45%7%7%9%32%
2214
21st to endDay
10%6%36%6%46%6%7%9%35%
2376
September1st to 10thDay
9%5%36%5%46%5%6%8%44%
2160
11th to 20thDay
15%5%35%5%345%5%8%43%
2080
21st to endDay
21%7%344245%5%7%39%
1920
October1st to 10thDay
16%5%35%423347%48%
1800
11th to 20thDay
14%5%24323446%54%
1800
21st to endDay
12%424434345%55%
1980
November1st to 10thDay
13%5%15%324336%54%
1857
11th to 20thDay
15%5%2432335%6%52%
1881
21st to endDay
15%5%3432245%7%51%
1534
December1st to 10thDay
18%7%3443345%6%42%
1520
11th to 20thDay
15%5%24323346%55%
1910
21st to endDay
17%6%25%4245%5%7%43%
3090
January1st to 10thNight
16%6%2443345%6%46%
2459
11th to 20thNight
16%7%36%5%3445%6%43%
2354
21st to endNight
16%5%245%24345%51%
2574
February1st to 10thNight
18%6%2442445%6%43%
2340
11th to 20thNight
20%6%25%5%2445%6%42%
2241
21st to endNight
16%6%245%25%5%5%5%46%
1673
March1st to 10thNight
13%5%25%424346%52%
1980
11th to 20thNight
17%5%26%5%35%45%7%42%
1980
21st to endNight
16%6%35%42445%7%44%
2178
April1st to 10thNight
15%6%2443445%6%49%
1846
11th to 20thNight
13%4245%2346%7%50%
1775
21st to endNight
13%326%5%35%5%5%7%46%
1800
May1st to 10thNight
10%5%26%5%3447%8%45%
1684
11th to 20thNight
16%5%25%6%345%5%8%41%
1592
21st to endNight
11%6%26%5%35%5%6%9%43%
1744
June1st to 10thNight
11%5%345%35%6%6%11%40%
1540
11th to 20thNight
10%5%36%6%35%6%5%10%40%
1459
21st to endNight
8%6%35%5%46%7%7%11%39%
1620
July1st to 10thNight
7%436%6%46%6%8%11%39%
1620
11th to 20thNight
7%416%5%36%7%8%13%39%
1620
21st to endNight
7%436%7%38%7%7%12%36%
1771
August1st to 10thNight
9%6%26%7%45%6%9%10%34%
1611
11th to 20thNight
10%6%45%7%45%6%9%8%36%
1667
21st to endNight
10%6%26%6%36%5%7%10%38%
1980
September1st to 10thNight
11%5%245%35%5%5%9%46%
1800
11th to 20thNight
13%6%26%5%3445%6%45%
1876
21st to endNight
21%7%37%5%3345%6%37%
2038
October1st to 10thNight
15%6%25%434446%48%
2160
11th to 20thNight
14%6%34423445%53%
2160
21st to endNight
12%5%2442435%5%55%
2376
November1st to 10thNight
14%5%25%423345%52%
2221
11th to 20thNight
13%5%245%2436%6%50%
2294
21st to endNight
13%5%2443445%6%51%
2645
December1st to 10thNight
17%7%35%5%34445%42%
2660
11th to 20thNight
17%6%25%32345%5%48%
3285
21st to endNight
17%6%34423446%46%
4560

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
40%38%24%19%6%
1707
11th to 20thDay
43%47%20%22%4
1629
21st to endDay
39%38%22%22%7%
1782
February1st to 10thDay
40%411%22%17%5%
1620
11th to 20thDay
42%5%6%19%22%6%
1614
21st to endDay
45%410%15%19%6%
1578
March1st to 10thDay
36%48%23%22%6%
1980
11th to 20thDay
40%6%10%21%16%7%
1980
21st to endDay
46%5%10%19%16%4
2178
April1st to 10thDay
30%411%25%22%9%
2114
11th to 20thDay
34%5%12%22%21%7%
2134
21st to endDay
39%5%11%22%18%5%
2160
May1st to 10thDay
38%6%16%20%17%3
2290
11th to 20thDay
43%7%14%23%11%2
2305
21st to endDay
40%8%16%24%12%
2531
June1st to 10thDay
39%8%14%23%15%1
2405
11th to 20thDay
33%9%17%24%15%2
2484
21st to endDay
38%10%15%21%14%2
2340
July1st to 10thDay
38%11%16%21%12%3
2275
11th to 20thDay
37%9%23%20%10%1
2271
21st to endDay
38%10%19%23%10%
2405
August1st to 10thDay
42%11%17%21%8%1
2314
11th to 20thDay
44%10%15%21%9%1
2214
21st to endDay
41%9%17%20%11%3
2376
September1st to 10thDay
36%8%15%18%18%4
2160
11th to 20thDay
39%6%10%20%21%3
2080
21st to endDay
44%6%10%20%17%4
1920
October1st to 10thDay
38%310%23%21%4
1800
11th to 20thDay
32%48%29%21%7%
1800
21st to endDay
32%47%23%25%9%
1980
November1st to 10thDay
34%37%23%27%6%
1857
11th to 20thDay
34%39%22%25%7%
1881
21st to endDay
34%39%23%26%6%
1534
December1st to 10thDay
42%6%10%19%18%4
1520
11th to 20thDay
33%37%27%22%8%
1906
21st to endDay
41%410%24%19%2
3090
January1st to 10thNight
39%5%8%19%23%6%
2459
11th to 20thNight
44%49%19%19%4
2354
21st to endNight
37%35%23%26%5%
2574
February1st to 10thNight
41%410%21%19%5%
2340
11th to 20thNight
44%48%17%20%7%
2243
21st to endNight
39%5%9%20%20%8%
1673
March1st to 10thNight
35%39%22%23%8%
1980
11th to 20thNight
43%5%8%20%19%5%
1980
21st to endNight
40%6%10%20%19%4
2178
April1st to 10thNight
36%5%9%18%25%7%
1846
11th to 20thNight
34%5%9%23%21%7%
1775
21st to endNight
37%5%9%26%18%5%
1800
May1st to 10thNight
35%8%12%24%17%4
1684
11th to 20thNight
42%7%12%21%16%2
1593
21st to endNight
37%8%15%26%13%1
1745
June1st to 10thNight
36%9%16%21%16%1
1540
11th to 20thNight
38%9%16%19%15%2
1459
21st to endNight
37%11%15%19%15%3
1620
July1st to 10thNight
35%12%17%22%11%3
1575
11th to 20thNight
32%12%21%22%10%3
1566
21st to endNight
37%11%19%22%11%1
1672
August1st to 10thNight
41%12%18%20%9%1
1600
11th to 20thNight
42%10%18%20%9%2
1667
21st to endNight
38%9%17%24%10%3
1980
September1st to 10thNight
35%9%14%22%16%5%
1800
11th to 20thNight
39%7%11%19%21%3
1876
21st to endNight
48%6%11%14%16%4
2038
October1st to 10thNight
37%5%9%21%23%5%
2160
11th to 20thNight
34%5%8%22%23%7%
2160
21st to endNight
33%37%22%26%9%
2376
November1st to 10thNight
36%38%19%27%7%
2221
11th to 20thNight
35%48%17%24%11%
2294
21st to endNight
34%47%22%27%6%
2645
December1st to 10thNight
45%49%19%19%4
2660
11th to 20thNight
38%38%21%22%8%
3288
21st to endNight
39%38%25%23%3
4560

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
25%26%36%11%3
270
11th to 20thDay
23%28%35%11%3
243
21st to endDay
20%27%40%11%2
264
February1st to 10thDay
22%25%39%12%2
240
11th to 20thDay
39%24%29%8%1
272
21st to endDay
26%23%32%16%4
346
March1st to 10thDay
23%23%32%17%5%
420
11th to 20thDay
24%21%37%12%5%
420
21st to endDay
23%20%36%16%5%1
462
April1st to 10thDay
21%17%36%19%7%
420
11th to 20thDay
17%18%33%21%8%4
412
21st to endDay
20%12%32%25%11%1
420
May1st to 10thDay
17%16%35%22%8%2
423
11th to 20thDay
18%8%25%28%18%3
447
21st to endDay
19%423%26%22%6%
485
June1st to 10thDay
12%5%25%33%19%6%
450
11th to 20thDay
12%5%23%28%24%7%
450
21st to endDay
9%422%36%24%5%
450
July1st to 10thDay
11%111%35%30%11%
445
11th to 20thDay
6%211%34%38%9%
444
21st to endDay
9%218%36%28%7%
488
August1st to 10thDay
13%320%30%23%10%
446
11th to 20thDay
13%212%30%31%12%
439
21st to endDay
10%413%31%26%17%
495
September1st to 10thDay
12%414%28%27%15%
450
11th to 20thDay
16%5%14%31%23%11%
450
21st to endDay
27%6%22%26%14%4
450
October1st to 10thDay
21%6%22%22%21%8%
450
11th to 20thDay
15%10%28%25%17%4
450
21st to endDay
16%13%25%28%15%3
495
November1st to 10thDay
19%10%30%24%15%3
455
11th to 20thDay
18%16%29%24%10%2
451
21st to endDay
20%18%26%22%13%2
194
December1st to 10thDay
24%19%40%11%6%
180
11th to 20thDay
21%16%34%23%42
180
21st to endDay
25%19%32%14%9%1
288
January1st to 10thNight
21%20%31%24%41
760
11th to 20thNight
21%15%34%24%6%
725
21st to endNight
19%16%37%24%4
792
February1st to 10thNight
22%16%36%23%4
720
11th to 20thNight
24%23%36%16%1
703
21st to endNight
20%17%37%24%2
592
March1st to 10thNight
19%15%36%25%4
720
11th to 20thNight
20%17%34%20%8%
720
21st to endNight
19%14%40%22%5%
792
April1st to 10thNight
19%17%32%26%6%
720
11th to 20thNight
16%12%35%26%10%
711
21st to endNight
15%10%37%31%8%
720
May1st to 10thNight
11%14%36%32%7%
604
11th to 20thNight
17%6%27%34%15%1
531
21st to endNight
14%217%38%26%2
584
June1st to 10thNight
12%121%41%22%2
460
11th to 20thNight
12%418%38%24%4
379
21st to endNight
9%314%43%28%3
540
July1st to 10thNight
8%112%41%34%3
525
11th to 20thNight
7%19%39%37%6%
522
21st to endNight
10%214%39%31%4
591
August1st to 10thNight
11%311%41%31%3
537
11th to 20thNight
13%210%36%34%5%
603
21st to endNight
12%212%33%35%6%
792
September1st to 10thNight
14%210%35%34%5%
720
11th to 20thNight
16%313%35%30%4
720
21st to endNight
24%419%32%20%1
720
October1st to 10thNight
18%5%19%28%25%5%
720
11th to 20thNight
16%10%25%28%20%2
720
21st to endNight
14%11%25%31%17%2
792
November1st to 10thNight
16%8%29%30%14%2
740
11th to 20thNight
16%12%29%31%11%
760
21st to endNight
15%14%27%29%14%1
760
December1st to 10thNight
22%14%29%28%8%
760
11th to 20thNight
19%11%32%31%7%
760
21st to endNight
22%17%26%28%7%
836
Page generated at 2024-01-08 22:31:24. Version ac07

Copyright 2024 Attilla Danko


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