Deep River
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Deep River clear sky chart from 2005-11-06 to 2024-02-20.

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
28%
22641
12%
80400
8%
22551
34%
22551
14%
58938

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
13%
755
5%
4420
3%
737
18%
737
3%
3523
January11th to 20thNight
19%
757
7%
4414
4%
740
24%
740
4%
3378
January21st to endNight
25%
831
8%
4655
9%
814
33%
814
6%
3808
February1st to 10thNight
18%
760
9%
2470
4%
760
25%
760
10%
1934
February11th to 20thNight
16%
741
12%
2399
5%
739
25%
739
12%
1795
February21st to endNight
21%
592
12%
1852
6%
592
30%
592
11%
1429
March1st to 10thNight
19%
720
13%
2077
6%
720
27%
720
15%
1576
March11th to 20thNight
20%
720
16%
1980
6%
720
30%
720
16%
1459
March21st to endNight
26%
792
19%
2122
8%
792
34%
792
20%
1485
April1st to 10thNight
24%
720
15%
1800
5%
720
29%
720
17%
1369
April11th to 20thNight
26%
711
17%
1775
6%
711
31%
711
21%
1292
April21st to endNight
28%
545
16%
1625
9%
545
35%
545
18%
1185
May1st to 10thNight
33%
370
17%
1450
14%
370
43%
370
17%
940
May11th to 20thNight
31%
354
20%
1416
18%
354
45%
354
18%
889
May21st to endNight
36%
388
13%
1551
11%
388
47%
388
20%
920
June1st to 10thNight
34%
360
9%
1440
10%
360
42%
360
17%
936
June11th to 20thNight
41%
360
12%
1415
13%
360
48%
360
22%
857
June21st to endNight
43%
360
12%
1260
12%
360
50%
360
20%
817
July1st to 10thNight
46%
350
15%
1328
17%
350
53%
350
29%
744
July11th to 20thNight
50%
348
15%
1392
17%
348
57%
348
24%
804
July21st to endNight
53%
394
14%
1486
16%
372
57%
372
24%
869
August1st to 10thNight
49%
464
16%
1528
13%
462
54%
462
26%
955
August11th to 20thNight
55%
534
17%
1598
12%
534
60%
534
30%
1004
August21st to endNight
44%
715
17%
1903
8%
715
49%
715
29%
1264
September1st to 10thNight
43%
720
18%
1800
8%
720
46%
720
32%
1195
September11th to 20thNight
44%
720
20%
1800
10%
720
46%
720
32%
1205
September21st to endNight
42%
720
18%
2070
13%
720
47%
720
24%
1383
October1st to 10thNight
31%
720
17%
2160
11%
720
39%
720
20%
1493
October11th to 20thNight
23%
720
11%
2160
7%
720
29%
720
14%
1656
October21st to endNight
23%
792
13%
2460
7%
792
31%
792
12%
1907
November1st to 10thNight
27%
740
13%
2510
9%
740
34%
740
14%
1799
November11th to 20thNight
17%
760
10%
2660
6%
760
23%
760
10%
2041
November21st to endNight
19%
760
7%
2660
4%
760
23%
760
7%
2189
December1st to 10thNight
14%
760
7%
2660
3%
760
18%
760
6%
2217
December11th to 20thNight
16%
760
9%
3261
4%
759
24%
759
7%
2578
December21st to endNight
13%
828
6%
4843
3%
817
19%
817
4%
4043

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
18%11%5%8%6%35%45%6%29%
78489
Night
17%13%5%9%7%34446%28%
80676
TransparencyDay
55%5%11%19%10%1
78194
Night
57%5%11%18%9%1
80505
SeeingDay
24%15%31%20%8%2
13582
Night
24%12%29%25%9%1
22664

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
17%17%8%12%9%3443319%
2517
11th to 20thDay
13%13%7%17%11%45%43420%
2520
21st to endDay
15%20%9%11%8%45%34418%
2996
February1st to 10thDay
11%16%7%12%10%5%6%5%45%19%
1710
11th to 20thDay
12%16%7%11%7%45%5%5%5%24%
1654
21st to endDay
19%15%7%8%8%35%44424%
1403
March1st to 10thDay
16%14%6%10%6%3445%6%27%
1877
11th to 20thDay
13%14%5%9%7%4445%5%28%
1980
21st to endDay
18%9%5%7%5%34346%37%
2233
April1st to 10thDay
23%13%48%5%34445%29%
2160
11th to 20thDay
21%10%47%5%34446%34%
2145
21st to endDay
22%10%37%6%34346%32%
2340
May1st to 10thDay
18%10%47%6%3445%6%33%
2508
11th to 20thDay
20%8%47%5%345%5%5%34%
2478
21st to endDay
16%7%35%6%345%6%8%36%
2725
June1st to 10thDay
20%8%47%7%45%5%5%6%30%
2520
11th to 20thDay
16%5%35%6%35%5%6%9%38%
2536
21st to endDay
18%6%36%6%46%5%6%7%32%
2700
July1st to 10thDay
13%436%6%45%5%7%7%38%
2584
11th to 20thDay
13%6%36%5%5%6%7%6%8%36%
2520
21st to endDay
12%5%36%6%46%6%7%9%35%
2744
August1st to 10thDay
13%7%36%7%5%6%5%6%9%34%
2397
11th to 20thDay
14%6%26%6%45%5%6%8%37%
2303
21st to endDay
14%7%36%5%36%5%5%9%35%
2435
September1st to 10thDay
14%6%36%5%345%5%7%41%
2160
11th to 20thDay
15%7%36%6%3445%7%42%
2160
21st to endDay
21%8%36%5%25%5%5%7%34%
1887
October1st to 10thDay
20%9%37%6%35%447%33%
1800
11th to 20thDay
26%13%46%7%4444423%
1800
21st to endDay
30%13%47%5%3445%6%20%
1895
November1st to 10thDay
17%12%48%6%345%5%5%29%
1564
11th to 20thDay
21%15%6%9%6%5%5%445%21%
1520
21st to endDay
26%19%6%10%6%45%44414%
1520
December1st to 10thDay
21%20%7%9%7%35%445%15%
1520
11th to 20thDay
20%17%7%11%7%35%44419%
1906
21st to endDay
25%21%7%11%7%2332417%
2772
January1st to 10thNight
16%20%7%11%9%45%445%15%
4429
11th to 20thNight
13%14%6%14%11%45%5%45%19%
4440
21st to endNight
12%21%9%12%8%5%5%335%17%
4657
February1st to 10thNight
13%13%7%12%9%5%5%6%45%21%
2470
11th to 20thNight
15%13%6%11%7%46%446%25%
2397
21st to endNight
14%17%6%11%7%44445%23%
1852
March1st to 10thNight
15%13%6%7%10%45%445%27%
2067
11th to 20thNight
14%14%5%8%6%24447%30%
1979
21st to endNight
15%11%47%5%23445%39%
2122
April1st to 10thNight
20%12%5%7%5%35%45%6%29%
1800
11th to 20thNight
20%10%45%5%2445%5%35%
1775
21st to endNight
23%9%37%6%345%46%31%
1625
May1st to 10thNight
20%8%28%5%2335%6%38%
1450
11th to 20thNight
19%6%26%6%3435%7%39%
1415
21st to endNight
14%5%35%5%35%5%5%7%42%
1550
June1st to 10thNight
17%7%36%5%46%5%6%7%35%
1440
11th to 20thNight
15%6%346%35%5%5%8%40%
1415
21st to endNight
17%5%35%5%35%5%6%8%36%
1260
July1st to 10thNight
11%5%26%435%5%6%8%46%
1368
11th to 20thNight
13%5%35%4345%5%8%44%
1440
21st to endNight
10%325%6%45%5%7%10%42%
1574
August1st to 10thNight
13%5%26%6%35%5%6%8%42%
1538
11th to 20thNight
11%6%246%45%6%6%7%43%
1598
21st to endNight
14%6%25%5%35%5%6%9%41%
1903
September1st to 10thNight
13%5%35%6%3445%7%45%
1800
11th to 20thNight
16%6%25%43435%6%45%
1800
21st to endNight
19%7%36%5%23447%40%
2070
October1st to 10thNight
22%8%26%43445%5%37%
2160
11th to 20thNight
24%12%47%6%3445%427%
2160
21st to endNight
25%13%37%6%4445%5%24%
2460
November1st to 10thNight
19%13%37%6%35%45%5%30%
2510
11th to 20thNight
20%14%6%9%7%45%44423%
2660
21st to endNight
25%17%5%10%7%3334418%
2660
December1st to 10thNight
22%21%6%11%6%3444315%
2660
11th to 20thNight
20%18%7%10%7%3433420%
3288
21st to endNight
25%20%6%13%7%2333315%
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
70%411%9%5%
2518
11th to 20thDay
69%310%12%6%
2520
21st to endDay
70%48%11%5%1
2996
February1st to 10thDay
68%38%14%6%1
1710
11th to 20thDay
62%412%13%9%1
1663
21st to endDay
64%27%15%10%
1403
March1st to 10thDay
58%410%17%10%1
1880
11th to 20thDay
58%410%15%12%2
1980
21st to endDay
51%38%20%13%5%
2233
April1st to 10thDay
58%47%18%11%3
2160
11th to 20thDay
53%37%22%13%2
2145
21st to endDay
55%37%16%15%3
2340
May1st to 10thDay
51%5%8%19%13%4
2508
11th to 20thDay
50%48%20%16%2
2482
21st to endDay
45%6%11%21%13%4
2725
June1st to 10thDay
53%5%11%18%12%1
2520
11th to 20thDay
43%5%11%25%13%3
2536
21st to endDay
48%7%11%21%12%1
2700
July1st to 10thDay
40%6%13%27%13%1
2514
11th to 20thDay
42%6%13%27%11%1
2445
21st to endDay
43%7%13%27%9%
2591
August1st to 10thDay
44%7%15%22%11%
2383
11th to 20thDay
42%7%16%25%9%1
2303
21st to endDay
44%6%15%24%10%1
2435
September1st to 10thDay
40%6%14%27%12%
2160
11th to 20thDay
42%5%13%29%10%1
2160
21st to endDay
50%5%13%25%7%
1887
October1st to 10thDay
51%6%11%20%11%1
1800
11th to 20thDay
63%5%13%14%4
1800
21st to endDay
66%411%14%41
1895
November1st to 10thDay
54%6%13%21%6%
1564
11th to 20thDay
65%5%12%13%6%1
1520
21st to endDay
74%410%8%5%
1520
December1st to 10thDay
72%310%11%3
1520
11th to 20thDay
70%46%13%7%1
1906
21st to endDay
75%26%14%3
2772
January1st to 10thNight
72%413%8%2
4429
11th to 20thNight
67%5%12%12%4
4440
21st to endNight
72%47%10%7%
4657
February1st to 10thNight
64%5%10%15%6%1
2470
11th to 20thNight
61%311%18%7%1
2399
21st to endNight
63%38%17%7%1
1852
March1st to 10thNight
59%39%16%11%2
2077
11th to 20thNight
55%410%17%12%1
1980
21st to endNight
48%48%21%15%4
2122
April1st to 10thNight
56%5%8%17%12%3
1800
11th to 20thNight
51%48%22%13%2
1775
21st to endNight
55%46%17%15%3
1625
May1st to 10thNight
48%5%6%21%15%4
1450
11th to 20thNight
47%37%22%18%3
1416
21st to endNight
40%6%13%21%16%4
1551
June1st to 10thNight
47%6%11%23%12%1
1440
11th to 20thNight
40%6%11%25%15%2
1415
21st to endNight
43%8%14%22%13%1
1260
July1st to 10thNight
32%7%14%27%18%2
1328
11th to 20thNight
36%7%14%27%15%1
1392
21st to endNight
37%7%16%30%10%
1486
August1st to 10thNight
39%6%17%24%14%
1528
11th to 20thNight
36%7%19%26%11%1
1598
21st to endNight
40%6%17%26%10%1
1903
September1st to 10thNight
39%6%14%29%13%
1800
11th to 20thNight
40%5%15%31%9%
1800
21st to endNight
44%5%14%29%8%
2070
October1st to 10thNight
49%5%11%23%12%
2160
11th to 20thNight
59%6%12%18%6%
2160
21st to endNight
61%5%10%16%7%
2460
November1st to 10thNight
55%5%14%18%8%
2510
11th to 20thNight
63%412%14%6%
2660
21st to endNight
70%411%12%3
2660
December1st to 10thNight
73%49%10%3
2660
11th to 20thNight
68%48%14%7%
3288
21st to endNight
76%36%11%4
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
22%23%38%14%2
180
11th to 20thDay
27%16%38%15%32
180
21st to endDay
23%15%36%20%6%
261
February1st to 10thDay
28%24%34%10%31
270
11th to 20thDay
23%30%38%9%
267
21st to endDay
34%20%31%14%
269
March1st to 10thDay
24%19%37%16%3
420
11th to 20thDay
25%20%33%18%41
420
21st to endDay
31%21%26%17%5%
462
April1st to 10thDay
30%20%28%15%6%1
420
11th to 20thDay
31%16%25%17%8%3
412
21st to endDay
30%16%32%16%6%1
420
May1st to 10thDay
27%16%31%17%7%2
423
11th to 20thDay
25%19%28%16%10%3
447
21st to endDay
21%14%32%23%8%2
485
June1st to 10thDay
23%13%36%21%7%1
450
11th to 20thDay
20%10%35%21%12%2
466
21st to endDay
20%14%31%23%11%2
630
July1st to 10thDay
13%9%31%36%10%2
509
11th to 20thDay
13%10%36%24%14%3
444
21st to endDay
13%10%31%31%13%2
488
August1st to 10thDay
15%7%33%28%11%6%
446
11th to 20thDay
17%7%23%30%15%8%
439
21st to endDay
18%12%31%22%11%7%
495
September1st to 10thDay
18%9%33%22%12%7%
450
11th to 20thDay
17%11%27%23%16%6%
450
21st to endDay
22%13%26%23%12%4
450
October1st to 10thDay
28%13%25%20%11%3
450
11th to 20thDay
29%21%30%14%5%2
450
21st to endDay
35%16%27%18%4
453
November1st to 10thDay
27%18%30%19%6%
258
11th to 20thDay
26%18%39%9%7%1
180
21st to endDay
34%20%34%8%31
180
December1st to 10thDay
31%11%40%14%3
180
11th to 20thDay
33%24%30%8%31
180
21st to endDay
33%19%33%11%4
198
January1st to 10thNight
28%14%35%20%3
760
11th to 20thNight
29%12%29%23%6%
760
21st to endNight
18%12%33%28%8%1
836
February1st to 10thNight
20%16%37%21%5%1
760
11th to 20thNight
24%16%36%19%4
742
21st to endNight
25%17%29%25%4
592
March1st to 10thNight
23%16%35%21%4
720
11th to 20thNight
23%19%32%19%7%
720
21st to endNight
21%15%32%23%7%1
792
April1st to 10thNight
28%13%30%25%4
720
11th to 20thNight
25%15%29%22%8%
711
21st to endNight
26%12%29%23%9%1
545
May1st to 10thNight
24%7%29%28%11%
370
11th to 20thNight
23%9%31%28%9%
354
21st to endNight
19%8%33%30%10%
389
June1st to 10thNight
19%6%33%35%7%1
360
11th to 20thNight
19%6%28%31%15%1
360
21st to endNight
20%6%24%33%15%1
360
July1st to 10thNight
11%5%31%38%15%1
350
11th to 20thNight
14%5%23%41%17%1
348
21st to endNight
10%427%40%18%1
394
August1st to 10thNight
15%5%23%34%22%1
464
11th to 20thNight
13%319%40%22%2
534
21st to endNight
16%7%27%31%17%2
715
September1st to 10thNight
16%6%29%30%17%2
720
11th to 20thNight
21%5%24%28%19%2
720
21st to endNight
23%9%22%29%16%1
720
October1st to 10thNight
25%10%29%24%12%1
720
11th to 20thNight
30%13%28%20%8%1
720
21st to endNight
33%11%27%25%41
792
November1st to 10thNight
27%13%27%26%6%1
740
11th to 20thNight
27%16%33%16%8%
760
21st to endNight
35%14%24%22%5%
760
December1st to 10thNight
33%16%29%16%5%
760
11th to 20thNight
30%14%29%22%41
760
21st to endNight
34%14%26%22%3
836
Page generated at 2024-02-17 06:28:40. Version ac07

Copyright 2024 Attilla Danko


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