Kirby Storter Roadside Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Kirby Storter Roadside Park clear sky chart from 2005-11-05 to 2017-08-12.

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
67%
16010
20%
46570
17%
15969
70%
15969
31%
29054

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
58%
719
20%
2327
18%
716
62%
716
28%
1409
January16th to endNight
58%
768
26%
2415
22%
768
64%
768
35%
1373
February1st to 15thNight
56%
701
27%
2105
21%
699
63%
699
36%
1223
February16th to endNight
65%
631
31%
1767
23%
631
72%
631
43%
976
March1st to 15thNight
62%
720
28%
1980
22%
720
68%
720
45%
1080
March16th to endNight
66%
768
29%
2112
24%
768
70%
768
44%
1177
April1st to 15thNight
72%
718
25%
1976
23%
718
74%
718
50%
1029
April16th to endNight
68%
720
27%
1847
20%
720
71%
720
44%
1063
May1st to 15thNight
80%
707
25%
1787
19%
707
81%
707
53%
968
May16th to endNight
77%
561
18%
1684
16%
561
77%
561
32%
1047
June1st to 15thNight
64%
540
7%
1620
6%
540
64%
540
17%
1235
June16th to endNight
76%
540
7%
1620
6%
540
76%
540
22%
1158
July1st to 15thNight
74%
510
5%
1530
6%
510
74%
510
21%
1115
July16th to endNight
82%
564
7%
1595
7%
531
82%
531
26%
1089
August1st to 15thNight
77%
554
6%
1610
6%
551
77%
551
23%
1150
August16th to endNight
68%
700
4%
1925
4%
700
68%
700
18%
1437
September1st to 15thNight
69%
660
5%
1815
5%
660
69%
660
19%
1333
September16th to endNight
59%
657
5%
1815
5%
657
59%
657
13%
1448
October1st to 15thNight
70%
660
19%
1885
20%
660
72%
660
28%
1237
October16th to endNight
62%
704
21%
2112
22%
704
64%
704
27%
1365
November1st to 15thNight
69%
700
30%
2101
29%
700
74%
700
39%
1191
November16th to endNight
61%
720
28%
2160
25%
720
66%
720
32%
1289
December1st to 15thNight
67%
720
25%
2286
25%
720
71%
720
33%
1315
December16th to endNight
71%
768
26%
2496
27%
768
74%
768
36%
1347

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
7%5%37%7%47%6%7%9%32%
47385
Night
6%425%5%35%5%7%10%44%
46775
TransparencyDay
44%10%14%15%10%3
47086
Night
32%10%18%21%13%3
46578
SeeingDay
8%110%20%28%30%
5832
Night
7%112%32%32%13%
16017

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 15thDay
7%6%35%7%36%6%7%9%37%
1611
16th to endDay
7%425%435%46%9%45%
1806
February1st to 15thDay
9%435%5%35%447%45%
1750
16th to endDay
5%3145%345%6%8%51%
1704
March1st to 15thDay
3325%5%46%6%7%9%45%
1980
16th to endDay
6%4246%46%45%9%45%
2111
April1st to 15thDay
4325%6%37%46%10%43%
1972
16th to endDay
6%335%6%46%7%7%8%41%
2112
May1st to 15thDay
42246%36%6%6%11%46%
2170
16th to endDay
8%5%37%8%5%7%7%7%8%29%
2431
June1st to 15thDay
12%8%48%10%6%9%7%8%8%14%
2340
16th to endDay
7%6%38%11%5%10%8%8%9%19%
2340
July1st to 15thDay
7%7%48%11%5%9%10%8%8%18%
2340
16th to endDay
6%6%48%9%6%10%9%9%10%19%
2465
August1st to 15thDay
6%6%38%9%6%10%8%9%9%20%
2238
16th to endDay
7%7%311%10%5%8%9%8%8%18%
1925
September1st to 15thDay
6%7%5%10%9%6%8%8%9%8%17%
1815
16th to endDay
13%9%5%11%9%5%8%7%6%6%15%
1815
October1st to 15thDay
8%6%37%7%46%7%8%9%30%
1744
16th to endDay
11%5%26%6%5%7%5%6%8%33%
1760
November1st to 15thDay
5%425%6%36%6%7%7%45%
1757
16th to endDay
8%5%25%5%35%6%6%8%42%
1800
December1st to 15thDay
8%6%26%6%3446%8%40%
1671
16th to endDay
5%325%437%6%7%9%43%
1728
January1st to 15thNight
7%425%6%35%6%6%9%41%
2327
16th to endNight
5%424425%5%6%9%48%
2415
February1st to 15thNight
9%4244235%5%7%50%
2103
16th to endNight
421343345%9%56%
1767
March1st to 15thNight
321342445%9%56%
1980
16th to endNight
5%2133245%5%9%55%
2112
April1st to 15thNight
221332335%10%61%
1976
16th to endNight
5%31342435%9%55%
1847
May1st to 15thNight
21232346%10%60%
1787
16th to endNight
7%4235%35%6%8%13%39%
1682
June1st to 15thNight
11%7%37%7%37%7%8%10%24%
1620
16th to endNight
4435%7%46%7%10%13%30%
1620
July1st to 15thNight
5%437%6%36%7%8%14%32%
1620
16th to endNight
2325%6%47%8%11%13%34%
1703
August1st to 15thNight
5%426%6%47%8%9%12%32%
1621
16th to endNight
5%438%7%47%8%9%12%27%
1925
September1st to 15thNight
5%437%7%47%7%10%13%28%
1815
16th to endNight
8%8%37%9%5%8%8%7%8%24%
1815
October1st to 15thNight
6%425%6%36%6%7%10%39%
1885
16th to endNight
10%6%25%5%36%45%9%39%
2112
November1st to 15thNight
5%3244245%5%8%52%
2101
16th to endNight
7%5%25%5%2446%8%48%
2160
December1st to 15thNight
6%424335%5%6%11%46%
2286
16th to endNight
431342446%10%52%
2496

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
40%8%14%17%12%5%
1612
16th to endDay
33%7%11%22%19%5%
1806
February1st to 15thDay
38%5%7%22%17%9%
1752
16th to endDay
27%8%11%25%20%7%
1704
March1st to 15thDay
31%7%12%23%19%5%
1980
16th to endDay
34%6%10%22%17%7%
2112
April1st to 15thDay
34%7%15%23%15%3
1972
16th to endDay
36%8%13%19%18%4
2112
May1st to 15thDay
30%7%16%24%16%5%
2170
16th to endDay
48%11%14%17%7%
2435
June1st to 15thDay
61%12%14%9%2
2340
16th to endDay
57%13%20%7%1
2340
July1st to 15thDay
56%18%19%5%
2201
16th to endDay
54%15%22%7%
2310
August1st to 15thDay
52%16%20%9%
2225
16th to endDay
57%16%19%5%
1925
September1st to 15thDay
57%17%18%5%
1815
16th to endDay
64%13%13%7%1
1815
October1st to 15thDay
46%11%12%15%12%2
1744
16th to endDay
44%7%10%15%14%7%
1760
November1st to 15thDay
35%5%12%19%20%7%
1757
16th to endDay
36%6%11%15%19%10%
1800
December1st to 15thDay
39%6%13%17%18%4
1671
16th to endDay
34%6%14%22%17%4
1728
January1st to 15thNight
35%7%14%24%13%3
2327
16th to endNight
30%6%12%27%17%5%
2415
February1st to 15thNight
31%5%9%24%19%9%
2112
16th to endNight
23%7%13%26%21%7%
1767
March1st to 15thNight
24%5%12%31%21%5%
1980
16th to endNight
23%6%14%27%21%5%
2112
April1st to 15thNight
19%5%17%31%19%5%
1976
16th to endNight
23%7%13%25%24%4
1847
May1st to 15thNight
18%7%18%33%18%4
1788
16th to endNight
33%9%20%26%11%
1684
June1st to 15thNight
49%14%22%11%2
1620
16th to endNight
38%17%30%11%2
1620
July1st to 15thNight
37%19%31%10%1
1530
16th to endNight
32%17%35%14%
1595
August1st to 15thNight
37%17%29%15%
1610
16th to endNight
42%17%29%8%
1925
September1st to 15thNight
40%18%30%9%1
1815
16th to endNight
52%17%17%11%1
1815
October1st to 15thNight
35%11%18%17%14%2
1885
16th to endNight
40%6%13%17%16%6%
2112
November1st to 15thNight
28%6%11%24%22%7%
2101
16th to endNight
33%6%10%19%20%9%
2160
December1st to 15thNight
30%8%15%22%19%3
2286
16th to endNight
26%7%13%27%21%3
2496

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
23%5%27%24%18%
90
16th to endDay
15%12%22%33%12%3
96
February1st to 15thDay
7%422%33%22%10%
90
16th to endDay
6%223%38%27%
205
March1st to 15thDay
3322%37%30%2
270
16th to endDay
7%219%33%30%7%
288
April1st to 15thDay
418%31%34%10%
270
16th to endDay
7%111%29%37%14%
270
May1st to 15thDay
311%19%42%22%
288
16th to endDay
5%16%19%29%37%
331
June1st to 15thDay
18%15%10%28%36%
315
16th to endDay
6%28%20%60%
315
July1st to 15thDay
6%1419%67%
305
16th to endDay
7%26%20%62%
326
August1st to 15thDay
7%5%23%62%
297
16th to endDay
10%45%20%58%
268
September1st to 15thDay
8%29%18%60%
255
16th to endDay
12%35%27%49%
254
October1st to 15thDay
6%16%21%43%20%
255
16th to endDay
13%114%30%26%13%
272
November1st to 15thDay
7%29%30%34%15%
265
16th to endDay
5%119%37%29%5%
270
December1st to 15thDay
19%15%31%26%6%
141
16th to endDay
2111%33%45%6%
96
January1st to 15thNight
10%317%40%25%1
720
16th to endNight
7%224%45%18%1
768
February1st to 15thNight
9%324%43%19%
704
16th to endNight
5%220%51%19%
631
March1st to 15thNight
5%224%46%20%1
720
16th to endNight
5%219%46%25%
768
April1st to 15thNight
3116%48%27%1
718
16th to endNight
6%16%47%27%
720
May1st to 15thNight
29%47%35%4
708
16th to endNight
6%1430%45%11%
563
June1st to 15thNight
12%15%18%42%20%
540
16th to endNight
417%47%38%
540
July1st to 15thNight
5%25%42%44%
510
16th to endNight
215%36%53%
564
August1st to 15thNight
8%15%43%40%
554
16th to endNight
7%1310%40%38%
700
September1st to 15thNight
6%48%41%39%
660
16th to endNight
14%312%41%26%
657
October1st to 15thNight
8%6%31%41%11%
660
16th to endNight
12%113%33%31%7%
704
November1st to 15thNight
5%215%40%32%4
700
16th to endNight
9%118%40%27%2
720
December1st to 15thNight
7%215%43%28%2
720
16th to endNight
5%114%39%35%3
768
Page generated at 2017-08-13 14:16:17. Version ac04

Copyright 2017 A. Danko


Kirby Storter Roadside Park Clear Sky Chart | Charts Home