Maumee
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Maumee clear sky chart from 2005-11-05 to 2018-03-21.

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
38%
16532
20%
49129
12%
16487
45%
16487
25%
32190

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
18%
975
15%
2716
5%
970
27%
970
17%
1998
January16th to endNight
17%
962
15%
2808
5%
962
27%
962
16%
2056
February1st to 15thNight
16%
764
13%
2292
4%
761
25%
761
16%
1654
February16th to endNight
17%
683
14%
2049
5%
683
25%
683
15%
1488
March1st to 15thNight
23%
780
16%
2327
9%
780
29%
780
19%
1600
March16th to endNight
27%
738
16%
2124
7%
738
36%
738
20%
1496
April1st to 15thNight
31%
539
20%
1797
11%
539
44%
539
24%
1128
April16th to endNight
37%
540
21%
1710
12%
540
47%
540
26%
1084
May1st to 15thNight
35%
540
15%
1620
8%
540
41%
540
20%
1136
May16th to endNight
52%
562
18%
1675
13%
561
56%
561
27%
1091
June1st to 15thNight
58%
540
19%
1440
15%
540
61%
540
38%
875
June16th to endNight
62%
540
21%
1440
14%
540
68%
540
42%
842
July1st to 15thNight
64%
510
17%
1360
13%
510
66%
510
37%
836
July16th to endNight
71%
564
25%
1483
20%
531
74%
531
42%
842
August1st to 15thNight
70%
539
22%
1635
20%
536
73%
536
39%
926
August16th to endNight
74%
573
25%
1910
25%
573
78%
573
38%
1008
September1st to 15thNight
64%
608
26%
1868
23%
608
68%
608
36%
1074
September16th to endNight
58%
717
29%
1980
22%
717
62%
717
37%
1172
October1st to 15thNight
50%
720
30%
1980
22%
720
57%
720
37%
1158
October16th to endNight
34%
768
24%
2452
17%
768
44%
768
26%
1508
November1st to 15thNight
37%
760
25%
2471
18%
760
48%
760
27%
1485
November16th to endNight
30%
780
22%
2535
14%
780
40%
780
20%
1650
December1st to 15thNight
22%
790
14%
2545
8%
790
30%
790
15%
1840
December16th to endNight
17%
1040
14%
2912
4%
1040
26%
1040
14%
2243

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%7%35%5%3445%7%39%
49713
Night
14%7%35%42445%6%40%
49305
Cloud CoverDay
15%7%35%5%2445%7%39%
49722
Night
14%7%35%424446%40%
49310
TransparencyDay
43%5%11%22%14%2
49407
Night
43%411%22%15%2
49129
SeeingDay
16%11%25%23%15%7%
6366
Night
17%10%28%26%15%2
16533

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 15thDay
20%9%5%9%423345%31%
1552
16th to endDay
13%13%47%6%2333437%
1762
February1st to 15thDay
16%11%5%8%423436%32%
1900
16th to endDay
16%11%47%5%33446%30%
1710
March1st to 15thDay
21%9%36%324345%35%
1953
16th to endDay
17%10%46%5%3345%7%32%
2238
April1st to 15thDay
17%5%35%424447%40%
2151
16th to endDay
19%6%34424337%38%
2248
May1st to 15thDay
23%7%35%5%23446%34%
2331
16th to endDay
12%6%36%6%45%6%5%7%36%
2437
June1st to 15thDay
9%4245%35%5%5%9%44%
2520
16th to endDay
8%5%345%36%6%5%9%42%
2520
July1st to 15thDay
11%5%25%5%35%5%7%9%37%
2520
16th to endDay
7%315%5%46%6%7%9%42%
2580
August1st to 15thDay
8%315%5%35%6%6%9%43%
2312
16th to endDay
7%425%5%35%5%5%9%46%
2292
September1st to 15thDay
13%5%15%42445%7%43%
2079
16th to endDay
12%5%135%23447%49%
1980
October1st to 15thDay
13%5%345%24446%45%
1980
16th to endDay
17%6%24423346%42%
1770
November1st to 15thDay
13%5%25%323446%47%
1717
16th to endDay
19%9%25%323345%40%
1755
December1st to 15thDay
22%11%46%424335%32%
1742
16th to endDay
22%13%46%5%23335%29%
1664
January1st to 15thNight
18%9%47%6%3444431%
2716
16th to endNight
15%12%6%6%5%35%33431%
2808
February1st to 15thNight
18%10%5%7%5%2345%5%30%
2290
16th to endNight
17%10%6%8%43435%5%30%
2049
March1st to 15thNight
18%8%45%42345%6%36%
2314
16th to endNight
18%8%36%5%25%35%6%34%
2124
April1st to 15thNight
15%7%35%42335%5%43%
1797
16th to endNight
15%6%25%415%447%41%
1710
May1st to 15thNight
18%7%36%5%2336%7%34%
1620
16th to endNight
9%436%6%36%5%6%8%39%
1673
June1st to 15thNight
9%41443435%10%48%
1440
16th to endNight
7%233245%7%11%49%
1440
July1st to 15thNight
8%4244245%6%8%48%
1440
16th to endNight
5%215%435%449%53%
1585
August1st to 15thNight
6%214425%5%6%9%50%
1646
16th to endNight
4213425%5%5%10%52%
1910
September1st to 15thNight
11%414325%347%51%
1868
16th to endNight
11%414423436%51%
1980
October1st to 15thNight
10%4145%2235%6%53%
1980
16th to endNight
17%6%25%323445%45%
2452
November1st to 15thNight
14%5%35%423346%46%
2471
16th to endNight
18%8%35%424336%39%
2535
December1st to 15thNight
20%11%48%5%2334430%
2545
16th to endNight
23%12%47%423445%26%
2912

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 15thDay
20%10%48%423345%31%
1552
16th to endDay
13%12%47%5%2434437%
1762
February1st to 15thDay
17%11%6%8%423346%32%
1900
16th to endDay
16%12%37%6%24446%30%
1710
March1st to 15thDay
21%8%46%323345%35%
1963
16th to endDay
17%9%36%5%33447%32%
2237
April1st to 15thDay
17%6%345%34446%41%
2151
16th to endDay
19%6%35%423337%39%
2248
May1st to 15thDay
22%7%35%5%2335%6%34%
2331
16th to endDay
12%6%36%6%35%6%6%7%36%
2437
June1st to 15thDay
10%4145%25%5%5%8%44%
2520
16th to endDay
9%424436%5%5%9%42%
2520
July1st to 15thDay
12%5%25%5%346%7%10%37%
2520
16th to endDay
6%3245%36%6%7%9%41%
2580
August1st to 15thDay
8%315%6%35%5%6%10%43%
2312
16th to endDay
7%325%5%35%46%9%45%
2292
September1st to 15thDay
13%6%15%3345%47%44%
2079
16th to endDay
12%5%1342345%6%50%
1980
October1st to 15thDay
13%6%25%5%2445%5%45%
1980
16th to endDay
17%5%2442435%6%42%
1770
November1st to 15thDay
13%5%24323447%47%
1717
16th to endDay
19%9%34322246%40%
1755
December1st to 15thDay
22%10%47%42333432%
1742
16th to endDay
21%14%36%5%23236%29%
1664
January1st to 15thNight
19%9%47%6%24445%31%
2716
16th to endNight
16%12%6%6%5%35%43431%
2808
February1st to 15thNight
18%11%5%7%5%2335%5%30%
2283
16th to endNight
18%11%5%7%433446%30%
2049
March1st to 15thNight
18%8%45%3235%5%5%35%
2327
16th to endNight
18%8%36%42445%5%34%
2124
April1st to 15thNight
15%6%35%42345%5%43%
1797
16th to endNight
15%6%25%424447%42%
1710
May1st to 15thNight
18%7%36%5%3345%8%34%
1619
16th to endNight
9%435%6%37%5%6%9%39%
1673
June1st to 15thNight
8%3244234410%48%
1440
16th to endNight
7%2133246%6%11%49%
1440
July1st to 15thNight
8%42443346%8%48%
1440
16th to endNight
5%21443445%9%52%
1585
August1st to 15thNight
6%2145%245%6%9%51%
1646
16th to endNight
42134345%6%9%52%
1910
September1st to 15thNight
11%314324447%51%
1868
16th to endNight
11%5%24414347%51%
1980
October1st to 15thNight
10%5%1342335%6%53%
1980
16th to endNight
17%7%24323345%45%
2452
November1st to 15thNight
14%5%34423346%46%
2471
16th to endNight
18%8%35%424336%39%
2535
December1st to 15thNight
20%11%48%5%2433431%
2545
16th to endNight
23%12%47%424445%26%
2912

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
55%310%16%13%1
1553
16th to endDay
50%411%25%7%1
1762
February1st to 15thDay
53%39%22%9%1
1902
16th to endDay
53%410%22%8%
1710
March1st to 15thDay
51%39%22%11%1
1963
16th to endDay
52%411%21%8%1
2238
April1st to 15thDay
43%411%23%15%
2151
16th to endDay
46%49%22%13%4
2248
May1st to 15thDay
50%5%12%18%12%
2331
16th to endDay
44%7%12%18%14%2
2441
June1st to 15thDay
36%6%12%24%16%2
2520
16th to endDay
36%6%13%22%16%3
2520
July1st to 15thDay
40%6%13%18%17%3
2371
16th to endDay
34%8%16%24%13%2
2419
August1st to 15thDay
34%7%12%25%18%2
2299
16th to endDay
32%6%12%25%17%5%
2292
September1st to 15thDay
38%5%9%23%16%6%
2079
16th to endDay
33%49%24%24%2
1980
October1st to 15thDay
39%48%25%20%2
1980
16th to endDay
41%310%25%17%1
1770
November1st to 15thDay
37%410%25%17%5%
1717
16th to endDay
46%39%23%16%1
1755
December1st to 15thDay
55%49%18%10%
1742
16th to endDay
57%410%19%6%1
1664
January1st to 15thNight
54%48%19%12%
2716
16th to endNight
55%410%21%8%
2808
February1st to 15thNight
54%412%20%7%1
2292
16th to endNight
54%412%18%9%
2049
March1st to 15thNight
47%5%9%21%13%2
2327
16th to endNight
49%413%23%7%1
2124
April1st to 15thNight
41%310%23%17%2
1797
16th to endNight
41%410%22%14%6%
1710
May1st to 15thNight
47%6%10%22%11%1
1620
16th to endNight
39%8%13%19%14%5%
1675
June1st to 15thNight
31%5%13%25%21%3
1440
16th to endNight
25%7%16%23%20%5%
1440
July1st to 15thNight
32%5%14%23%18%5%
1360
16th to endNight
26%5%12%33%17%3
1483
August1st to 15thNight
27%6%17%24%19%3
1635
16th to endNight
25%6%13%28%20%5%
1910
September1st to 15thNight
31%410%23%21%7%
1868
16th to endNight
32%48%24%26%4
1980
October1st to 15thNight
31%310%26%22%5%
1980
16th to endNight
40%38%27%17%2
2452
November1st to 15thNight
38%49%22%19%5%
2471
16th to endNight
46%39%23%16%
2535
December1st to 15thNight
55%39%19%10%
2545
16th to endNight
59%5%9%17%8%
2912

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
31%19%30%14%21
135
16th to endDay
16%35%36%9%1
144
February1st to 15thDay
28%35%22%13%
135
16th to endDay
25%20%42%9%1
120
March1st to 15thDay
23%26%39%10%
148
16th to endDay
22%16%33%18%7%
311
April1st to 15thDay
18%18%27%25%8%1
270
16th to endDay
22%11%32%18%12%3
270
May1st to 15thDay
27%15%26%17%8%4
288
16th to endDay
17%10%27%20%12%11%
337
June1st to 15thDay
11%5%24%34%16%7%
495
16th to endDay
10%7%29%31%14%6%
495
July1st to 15thDay
14%5%23%29%17%9%
475
16th to endDay
6%214%35%26%14%
440
August1st to 15thDay
14%212%22%30%18%
313
16th to endDay
11%214%27%28%15%
332
September1st to 15thDay
12%316%27%26%13%
315
16th to endDay
16%414%19%32%11%
314
October1st to 15thDay
11%9%25%27%19%6%
315
16th to endDay
17%12%38%23%7%
165
November1st to 15thDay
20%14%26%22%10%5%
135
16th to endDay
22%16%37%17%6%
135
December1st to 15thDay
17%29%29%14%6%1
135
16th to endDay
33%22%38%4
144
January1st to 15thNight
24%15%37%19%3
975
16th to endNight
20%19%37%20%2
962
February1st to 15thNight
24%16%38%18%1
764
16th to endNight
23%16%39%18%2
683
March1st to 15thNight
21%16%36%22%2
780
16th to endNight
21%12%33%25%6%
738
April1st to 15thNight
17%15%32%24%10%
539
16th to endNight
17%7%32%32%9%1
540
May1st to 15thNight
21%8%29%27%12%
540
16th to endNight
11%424%30%24%4
563
June1st to 15thNight
10%321%41%22%
540
16th to endNight
6%224%38%27%1
540
July1st to 15thNight
10%14%39%30%3
510
16th to endNight
6%111%36%35%7%
564
August1st to 15thNight
7%113%33%37%6%
539
16th to endNight
5%11%34%40%6%
573
September1st to 15thNight
12%314%31%33%5%
608
16th to endNight
12%5%17%26%32%5%
717
October1st to 15thNight
12%6%24%26%23%5%
720
16th to endNight
20%9%32%23%12%1
768
November1st to 15thNight
16%11%30%25%14%1
760
16th to endNight
22%14%28%26%8%
780
December1st to 15thNight
25%14%31%20%7%
790
16th to endNight
28%15%33%18%3
1040
Page generated at 2018-03-22 11:34:19. Version ac04

Copyright 2018 A. Danko


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