Bridgeport
Clear Sky Chart
History

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

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
35%
23071
19%
74571
10%
23030
46%
23030
23%
47842

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
21%
760
23%
2649
9%
757
39%
757
21%
1595
January11th to 20thNight
22%
724
19%
2532
6%
724
38%
724
17%
1646
January21st to endNight
22%
792
22%
2696
9%
792
39%
792
22%
1617
February1st to 10thNight
21%
720
17%
2287
6%
720
35%
720
18%
1531
February11th to 20thNight
19%
703
20%
2100
6%
700
35%
700
22%
1379
February21st to endNight
20%
592
24%
1776
9%
592
40%
592
21%
1166
March1st to 10thNight
25%
719
22%
2160
9%
719
42%
719
26%
1360
March11th to 20thNight
27%
720
20%
2102
9%
720
40%
720
24%
1368
March21st to endNight
27%
792
22%
1980
7%
792
38%
792
26%
1368
April1st to 10thNight
30%
720
19%
1800
6%
720
37%
720
25%
1267
April11th to 20thNight
37%
711
18%
1775
6%
711
43%
711
28%
1230
April21st to endNight
33%
644
19%
1724
7%
644
41%
644
26%
1191
May1st to 10thNight
33%
540
14%
1620
7%
540
39%
540
19%
1147
May11th to 20thNight
35%
436
18%
1498
11%
436
44%
436
19%
996
May21st to endNight
50%
388
14%
1551
15%
388
54%
388
18%
988
June1st to 10thNight
44%
360
16%
1440
17%
360
52%
360
19%
903
June11th to 20thNight
56%
360
14%
1440
19%
360
60%
360
21%
877
June21st to endNight
62%
360
15%
1440
19%
360
66%
360
24%
845
July1st to 10thNight
57%
350
13%
1400
17%
350
60%
350
21%
862
July11th to 20thNight
63%
348
14%
1392
19%
348
65%
348
21%
844
July21st to endNight
64%
394
17%
1486
21%
372
68%
372
24%
880
August1st to 10thNight
62%
437
17%
1501
16%
435
65%
435
27%
895
August11th to 20thNight
57%
710
14%
1774
8%
710
58%
710
27%
1247
August21st to endNight
59%
792
18%
1980
9%
792
62%
792
33%
1313
September1st to 10thNight
50%
720
22%
1800
11%
720
54%
720
31%
1225
September11th to 20thNight
53%
720
25%
1912
17%
720
58%
720
35%
1188
September21st to endNight
46%
720
24%
1980
15%
720
53%
720
28%
1320
October1st to 10thNight
36%
720
16%
2021
11%
720
41%
720
22%
1412
October11th to 20thNight
40%
720
23%
2160
13%
720
52%
720
29%
1333
October21st to endNight
27%
792
18%
2567
10%
792
39%
792
20%
1715
November1st to 10thNight
37%
740
23%
2407
13%
740
50%
740
27%
1442
November11th to 20thNight
28%
760
25%
2470
13%
760
44%
760
23%
1529
November21st to endNight
29%
760
23%
2501
10%
760
44%
760
24%
1505
December1st to 10thNight
24%
760
19%
2660
7%
760
39%
760
18%
1713
December11th to 20thNight
24%
760
18%
3180
6%
759
38%
759
15%
1954
December21st to endNight
22%
827
13%
4810
8%
817
38%
817
11%
2991

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%245%345%5%7%42%
74769
Night
18%6%25%43445%6%43%
74924
TransparencyDay
40%7%13%23%16%2
74474
Night
42%6%12%22%16%2
74753
SeeingDay
18%6%25%30%17%4
13897
Night
20%8%30%29%11%1
23082

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
16%6%24435%46%6%44%
1517
11th to 20thDay
19%7%35%5%346%6%7%37%
1440
21st to endDay
15%7%35%425%5%5%8%43%
1658
February1st to 10thDay
19%6%25%5%45%5%5%7%38%
1670
11th to 20thDay
16%6%246%3345%8%43%
1748
21st to endDay
22%8%24434446%38%
1480
March1st to 10thDay
15%6%25%5%3445%7%43%
1797
11th to 20thDay
16%6%245%36%5%7%7%39%
1856
21st to endDay
21%7%35%434346%40%
2376
April1st to 10thDay
19%6%25%4245%5%7%40%
2160
11th to 20thDay
18%5%4443445%6%42%
2134
21st to endDay
22%5%245%24446%41%
2236
May1st to 10thDay
25%7%2442446%7%35%
2340
11th to 20thDay
19%5%35%425%5%6%6%40%
2410
21st to endDay
16%5%245%245%6%8%43%
2725
June1st to 10thDay
20%5%245%246%6%8%37%
2520
11th to 20thDay
17%5%345%35%5%6%9%38%
2520
21st to endDay
15%5%25%5%445%6%9%41%
2520
July1st to 10thDay
13%5%25%5%35%6%7%9%41%
2520
11th to 20thDay
12%5%24435%6%7%9%43%
2520
21st to endDay
13%6%25%6%46%5%6%9%40%
2744
August1st to 10thDay
12%5%25%5%46%5%7%9%41%
2408
11th to 20thDay
12%5%25%5%346%6%8%43%
2126
21st to endDay
13%5%345%35%5%6%8%45%
2376
September1st to 10thDay
14%5%35%5%36%448%45%
2160
11th to 20thDay
13%423325%446%52%
2048
21st to endDay
19%5%25%43445%6%42%
1980
October1st to 10thDay
23%6%24333447%42%
1936
11th to 20thDay
17%42442436%7%46%
1800
21st to endDay
22%5%145%3445%7%40%
1788
November1st to 10thDay
14%6%2443435%5%50%
1671
11th to 20thDay
19%5%24423345%48%
1710
21st to endDay
17%5%2442445%7%45%
1677
December1st to 10thDay
19%6%25%435%46%7%37%
1520
11th to 20thDay
24%5%23223347%45%
1906
21st to endDay
20%10%35%6%34447%33%
2772
January1st to 10thNight
17%6%24423446%47%
2649
11th to 20thNight
21%7%3442345%6%40%
2532
21st to endNight
15%9%25%423447%45%
2696
February1st to 10thNight
18%9%35%5%34445%40%
2287
11th to 20thNight
18%8%35%5%34347%41%
2098
21st to endNight
20%7%345%2444442%
1776
March1st to 10thNight
18%6%2342445%7%45%
2150
11th to 20thNight
18%6%25%5%3445%7%42%
2101
21st to endNight
18%8%3443345%5%43%
1980
April1st to 10thNight
19%7%36%5%245%46%40%
1800
11th to 20thNight
20%6%345%24446%42%
1775
21st to endNight
21%6%35%5%2444442%
1724
May1st to 10thNight
23%7%35%6%3435%7%34%
1620
11th to 20thNight
22%6%35%4345%5%6%37%
1497
21st to endNight
19%6%35%42446%7%40%
1550
June1st to 10thNight
20%5%25%5%34446%41%
1440
11th to 20thNight
17%6%35%43447%9%40%
1440
21st to endNight
13%5%15%5%3447%9%44%
1440
July1st to 10thNight
13%5%26%6%35%6%6%8%41%
1440
11th to 20thNight
13%5%25%5%35%6%6%9%39%
1440
21st to endNight
13%425%437%5%7%9%41%
1574
August1st to 10thNight
9%5%26%445%6%7%7%45%
1511
11th to 20thNight
13%6%36%6%5%6%5%6%8%36%
1774
21st to endNight
14%5%2443446%8%45%
1980
September1st to 10thNight
15%6%25%5%345%46%45%
1800
11th to 20thNight
15%424323346%52%
1912
21st to endNight
19%6%34334435%45%
1980
October1st to 10thNight
21%7%25%5%2435%5%41%
2021
11th to 20thNight
16%5%25%434347%48%
2160
21st to endNight
23%7%24423445%41%
2567
November1st to 10thNight
13%5%2443445%6%49%
2407
11th to 20thNight
20%6%23323346%48%
2470
21st to endNight
16%5%2442435%7%47%
2501
December1st to 10thNight
21%6%35%434446%40%
2660
11th to 20thNight
21%6%25%42445%6%43%
3288
21st to endNight
22%9%35%424345%39%
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
39%6%11%27%13%4
1518
11th to 20thDay
44%6%15%19%13%2
1440
21st to endDay
40%6%11%24%16%3
1658
February1st to 10thDay
45%414%22%13%2
1670
11th to 20thDay
40%6%11%25%16%3
1757
21st to endDay
47%410%21%14%3
1480
March1st to 10thDay
40%5%15%23%14%3
1800
11th to 20thDay
40%6%14%23%16%2
1856
21st to endDay
46%5%8%18%19%5%
2376
April1st to 10thDay
41%7%11%21%16%4
2160
11th to 20thDay
40%412%21%19%3
2134
21st to endDay
42%5%11%21%16%4
2236
May1st to 10thDay
44%7%11%20%14%2
2340
11th to 20thDay
40%7%13%20%17%3
2414
21st to endDay
37%9%17%21%14%2
2725
June1st to 10thDay
40%8%14%23%14%1
2520
11th to 20thDay
39%8%15%23%13%1
2520
21st to endDay
36%9%15%25%14%1
2520
July1st to 10thDay
35%9%14%23%17%2
2450
11th to 20thDay
34%7%17%26%14%2
2445
21st to endDay
36%8%15%21%18%2
2591
August1st to 10thDay
35%8%17%25%14%1
2394
11th to 20thDay
35%7%16%26%15%1
2126
21st to endDay
34%8%12%23%19%2
2376
September1st to 10thDay
36%8%14%22%18%2
2160
11th to 20thDay
31%6%12%25%24%2
2048
21st to endDay
41%6%11%21%19%3
1980
October1st to 10thDay
42%6%10%22%17%3
1936
11th to 20thDay
36%5%15%25%17%2
1800
21st to endDay
44%6%11%21%16%2
1788
November1st to 10thDay
36%6%12%23%20%2
1671
11th to 20thDay
39%411%22%21%3
1710
21st to endDay
38%5%14%27%13%3
1677
December1st to 10thDay
45%6%15%19%14%1
1520
11th to 20thDay
41%316%21%17%2
1906
21st to endDay
50%7%11%22%9%1
2772
January1st to 10thNight
39%5%12%24%16%4
2649
11th to 20thNight
45%6%14%23%10%2
2532
21st to endNight
40%412%23%18%3
2696
February1st to 10thNight
46%6%12%21%13%2
2287
11th to 20thNight
44%411%20%16%5%
2100
21st to endNight
44%48%23%16%4
1776
March1st to 10thNight
39%5%13%24%15%4
2160
11th to 20thNight
42%6%11%22%16%4
2102
21st to endNight
43%6%9%17%19%6%
1980
April1st to 10thNight
45%6%11%19%17%3
1800
11th to 20thNight
44%5%10%19%21%1
1775
21st to endNight
45%5%9%20%15%5%
1724
May1st to 10thNight
50%6%10%16%15%2
1620
11th to 20thNight
47%6%11%17%17%2
1498
21st to endNight
44%8%15%20%12%1
1551
June1st to 10thNight
45%5%11%20%18%2
1440
11th to 20thNight
40%8%14%25%12%1
1440
21st to endNight
36%9%14%26%14%1
1440
July1st to 10thNight
39%9%15%20%15%2
1400
11th to 20thNight
39%9%14%26%11%1
1392
21st to endNight
36%9%16%22%15%2
1486
August1st to 10thNight
33%10%17%23%15%1
1501
11th to 20thNight
43%8%14%24%11%1
1774
21st to endNight
35%8%14%21%19%2
1980
September1st to 10thNight
40%6%10%26%16%2
1800
11th to 20thNight
34%6%11%22%24%3
1912
21st to endNight
41%6%8%20%21%3
1980
October1st to 10thNight
46%7%9%21%13%3
2021
11th to 20thNight
38%5%13%28%15%1
2160
21st to endNight
46%6%11%20%16%1
2567
November1st to 10thNight
37%6%12%22%20%4
2407
11th to 20thNight
40%5%9%24%19%4
2470
21st to endNight
38%5%13%30%13%2
2501
December1st to 10thNight
45%5%13%21%15%1
2660
11th to 20thNight
44%413%18%18%3
3288
21st to endNight
48%5%12%23%11%1
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
19%14%33%24%8%1
180
11th to 20thDay
15%15%47%17%6%1
160
21st to endDay
20%7%41%24%7%1
210
February1st to 10thDay
25%10%40%21%3
290
11th to 20thDay
19%10%43%25%2
416
21st to endDay
24%13%37%21%5%
346
March1st to 10thDay
15%9%38%31%6%
420
11th to 20thDay
16%7%42%28%6%1
420
21st to endDay
23%8%36%24%8%1
462
April1st to 10thDay
22%8%34%24%11%1
420
11th to 20thDay
18%7%31%31%13%1
412
21st to endDay
26%6%26%32%9%1
420
May1st to 10thDay
27%5%26%31%9%2
423
11th to 20thDay
19%424%34%17%1
447
21st to endDay
18%214%33%27%6%
485
June1st to 10thDay
19%414%35%23%5%
450
11th to 20thDay
17%318%37%22%4
450
21st to endDay
14%217%36%26%5%
450
July1st to 10thDay
14%213%31%31%9%
445
11th to 20thDay
12%29%32%35%9%
444
21st to endDay
13%313%37%30%3
488
August1st to 10thDay
11%211%39%29%9%
446
11th to 20thDay
15%18%35%32%9%
439
21st to endDay
12%214%36%26%9%
495
September1st to 10thDay
18%216%29%24%11%
450
11th to 20thDay
15%318%29%25%10%
450
21st to endDay
21%321%31%19%5%
450
October1st to 10thDay
26%5%18%25%19%7%
450
11th to 20thDay
18%7%26%30%17%2
450
21st to endDay
25%10%28%26%11%1
399
November1st to 10thDay
16%9%24%32%16%4
365
11th to 20thDay
20%11%36%25%8%
370
21st to endDay
18%12%31%29%10%
337
December1st to 10thDay
17%13%37%24%8%1
180
11th to 20thDay
27%14%31%24%4
180
21st to endDay
23%9%38%22%8%1
198
January1st to 10thNight
19%15%40%21%5%
760
11th to 20thNight
24%12%36%23%3
724
21st to endNight
19%13%41%24%3
792
February1st to 10thNight
21%12%39%26%2
720
11th to 20thNight
23%11%43%22%2
703
21st to endNight
24%12%39%22%4
592
March1st to 10thNight
22%9%39%25%5%
720
11th to 20thNight
20%9%39%26%6%1
720
21st to endNight
22%7%38%26%6%1
792
April1st to 10thNight
22%8%35%29%6%1
720
11th to 20thNight
23%5%30%32%10%
711
21st to endNight
22%5%32%33%8%1
644
May1st to 10thNight
26%6%26%30%11%1
540
11th to 20thNight
22%332%32%11%
436
21st to endNight
22%314%35%24%2
389
June1st to 10thNight
20%423%34%19%2
360
11th to 20thNight
19%316%43%19%
360
21st to endNight
14%113%50%21%1
360
July1st to 10thNight
14%117%38%27%3
350
11th to 20thNight
13%212%43%27%3
348
21st to endNight
15%214%46%22%2
394
August1st to 10thNight
9%117%45%26%2
437
11th to 20thNight
15%213%36%29%4
710
21st to endNight
14%216%34%29%5%
792
September1st to 10thNight
17%222%33%22%4
720
11th to 20thNight
18%319%34%20%6%
720
21st to endNight
21%323%31%19%3
720
October1st to 10thNight
24%7%27%23%16%4
720
11th to 20thNight
18%9%29%32%11%1
720
21st to endNight
26%10%33%23%7%1
792
November1st to 10thNight
16%8%34%28%12%2
740
11th to 20thNight
23%12%34%24%8%1
760
21st to endNight
18%14%34%27%7%1
760
December1st to 10thNight
24%13%34%22%6%1
760
11th to 20thNight
23%13%36%25%4
760
21st to endNight
24%12%37%23%3
836
Page generated at 2024-01-08 11:14:20. Version ac07

Copyright 2024 Attilla Danko


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