Kalispell
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Kalispell 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
45%
23414
10%
74905
10%
23379
46%
23379
16%
54781

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
22%
948
3%
2836
2%
946
23%
946
5%
2564
January11th to 20thNight
29%
734
5%
2542
5%
734
30%
734
7%
2156
January21st to endNight
33%
792
7%
2772
7%
792
35%
792
7%
2296
February1st to 10thNight
29%
720
5%
2465
5%
720
31%
720
8%
2043
February11th to 20thNight
31%
704
5%
2241
5%
700
33%
700
10%
1806
February21st to endNight
35%
592
10%
1776
9%
592
36%
592
12%
1421
March1st to 10thNight
38%
720
8%
2160
7%
720
39%
720
13%
1694
March11th to 20thNight
40%
720
10%
2004
8%
720
42%
720
16%
1557
March21st to endNight
38%
792
6%
2152
3%
792
39%
792
13%
1739
April1st to 10thNight
44%
716
9%
1796
5%
716
46%
716
19%
1364
April11th to 20thNight
38%
533
12%
1601
9%
533
40%
533
17%
1176
April21st to endNight
42%
540
10%
1620
8%
540
43%
540
20%
1139
May1st to 10thNight
49%
540
10%
1620
10%
540
49%
540
21%
1122
May11th to 20thNight
57%
366
14%
1354
19%
366
59%
366
20%
862
May21st to endNight
51%
388
8%
1358
10%
388
52%
388
16%
952
June1st to 10thNight
51%
360
7%
1260
6%
360
53%
360
19%
835
June11th to 20thNight
46%
360
5%
1260
4%
360
47%
360
17%
878
June21st to endNight
68%
360
12%
1260
12%
360
70%
360
34%
671
July1st to 10thNight
80%
350
17%
1225
19%
350
82%
350
53%
514
July11th to 20thNight
76%
348
22%
1262
29%
348
80%
348
54%
516
July21st to endNight
83%
394
27%
1488
41%
372
88%
372
57%
544
August1st to 10thNight
80%
399
28%
1465
35%
397
84%
397
52%
605
August11th to 20thNight
78%
534
27%
1602
25%
534
79%
534
52%
780
August21st to endNight
71%
594
30%
1782
26%
594
72%
594
44%
943
September1st to 10thNight
71%
692
22%
1795
16%
692
72%
692
47%
1021
September11th to 20thNight
69%
720
24%
1980
20%
720
70%
720
38%
1171
September21st to endNight
63%
720
19%
1980
16%
720
64%
720
33%
1245
October1st to 10thNight
56%
720
16%
2022
13%
720
58%
720
26%
1360
October11th to 20thNight
54%
720
14%
2263
13%
720
57%
720
23%
1497
October21st to endNight
40%
792
11%
2574
9%
792
43%
792
16%
1870
November1st to 10thNight
35%
740
6%
2405
6%
740
37%
740
10%
1936
November11th to 20thNight
33%
926
5%
2636
3%
926
34%
926
11%
2152
November21st to endNight
37%
950
4%
2806
3%
950
37%
950
11%
2309
December1st to 10thNight
34%
950
5%
2850
4%
950
34%
950
9%
2428
December11th to 20thNight
27%
950
2%
3501
2%
949
27%
949
5%
3069
December21st to endNight
20%
1030
1%
5192
1%
1026
22%
1026
3%
4546

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
10%9%48%7%45%5%6%7%35%
74595
Night
9%10%48%7%45%5%6%7%35%
75108
TransparencyDay
47%10%14%17%10%2
74288
Night
49%12%14%16%8%2
74933
SeeingDay
14%15%24%25%17%4
14066
Night
16%11%19%33%18%2
23432

By Month

Percentage Cloud Cover NW (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
12%19%7%11%11%46%447%14%
1336
11th to 20thDay
11%16%7%13%10%5%7%6%6%6%14%
1440
21st to endDay
9%19%7%14%8%35%5%46%19%
1584
February1st to 10thDay
12%18%7%12%9%5%5%6%5%6%16%
1494
11th to 20thDay
7%15%6%12%9%47%6%8%7%19%
1607
21st to endDay
7%17%7%12%9%47%6%6%5%20%
1480
March1st to 10thDay
8%16%7%11%9%46%5%5%7%22%
1800
11th to 20thDay
7%14%5%8%8%5%6%6%6%9%26%
1955
21st to endDay
10%14%6%10%8%5%7%6%7%8%20%
2202
April1st to 10thDay
9%12%6%9%9%6%6%6%7%7%23%
2164
11th to 20thDay
14%12%5%10%7%5%6%6%6%6%26%
2310
21st to endDay
14%9%49%8%46%6%6%6%28%
2340
May1st to 10thDay
11%8%37%7%46%6%6%7%35%
2340
11th to 20thDay
11%8%47%7%46%7%6%8%34%
2537
21st to endDay
19%9%47%7%46%5%5%7%26%
2917
June1st to 10thDay
18%7%46%7%45%5%6%7%31%
2700
11th to 20thDay
17%6%37%7%47%7%6%8%29%
2700
21st to endDay
8%4245%35%6%7%10%47%
2700
July1st to 10thDay
4213425%5%5%7%61%
2700
11th to 20thDay
422232345%7%65%
2652
21st to endDay
2112222346%73%
2741
August1st to 10thDay
5%2132245%6%8%62%
2465
11th to 20thDay
6%31331445%7%62%
2299
21st to endDay
6%3245%345%6%8%53%
2574
September1st to 10thDay
6%4245%345%6%7%55%
2162
11th to 20thDay
8%4345%46%5%6%8%48%
1980
21st to endDay
8%5%25%6%46%6%7%7%44%
1980
October1st to 10thDay
12%7%36%7%35%5%6%7%38%
1937
11th to 20thDay
9%8%38%7%45%5%6%8%35%
1692
21st to endDay
12%11%410%7%45%5%6%7%28%
1782
November1st to 10thDay
16%15%5%9%8%45%5%6%7%20%
1674
11th to 20thDay
10%13%6%12%8%5%6%5%7%6%22%
1524
21st to endDay
10%14%5%11%10%6%5%5%6%7%20%
1373
December1st to 10thDay
9%19%7%10%9%5%6%445%21%
1330
11th to 20thDay
8%18%7%16%11%6%6%6%5%5%12%
1682
21st to endDay
10%15%7%18%14%6%5%45%411%
2442
January1st to 10thNight
12%21%6%11%10%5%6%5%5%6%14%
2836
11th to 20thNight
11%16%6%12%8%445%5%7%22%
2542
21st to endNight
10%15%6%9%8%5%6%5%6%7%24%
2772
February1st to 10thNight
13%14%7%9%8%46%5%5%6%23%
2465
11th to 20thNight
8%16%6%9%7%35%5%6%7%27%
2240
21st to endNight
6%14%6%9%9%5%6%6%6%6%28%
1776
March1st to 10thNight
9%14%48%7%45%47%7%29%
2160
11th to 20thNight
7%10%47%8%5%7%7%7%7%33%
2004
21st to endNight
8%9%49%8%48%6%8%8%27%
2152
April1st to 10thNight
8%10%48%6%36%5%5%9%36%
1796
11th to 20thNight
10%9%48%7%46%6%6%6%35%
1601
21st to endNight
12%7%47%5%35%5%5%9%38%
1620
May1st to 10thNight
7%7%36%7%45%5%8%9%38%
1620
11th to 20thNight
10%6%35%6%36%6%6%8%41%
1354
21st to endNight
15%9%46%6%36%5%5%8%34%
1358
June1st to 10thNight
14%6%45%5%35%6%5%6%40%
1260
11th to 20thNight
16%5%25%5%45%7%7%7%38%
1260
21st to endNight
5%3244345%6%7%57%
1260
July1st to 10thNight
31222335%8%71%
1260
11th to 20thNight
4212213246%74%
1304
21st to endNight
2112212346%75%
1576
August1st to 10thNight
4312213248%70%
1473
11th to 20thNight
5%1122235%6%8%65%
1602
21st to endNight
6%32333446%6%60%
1782
September1st to 10thNight
6%22443446%7%60%
1795
11th to 20thNight
7%425%43446%7%55%
1980
21st to endNight
8%425%5%35%46%9%50%
1980
October1st to 10thNight
9%6%35%6%35%45%7%46%
2022
11th to 20thNight
8%5%35%5%5%6%5%6%8%43%
2263
21st to endNight
11%9%38%7%45%5%47%36%
2574
November1st to 10thNight
13%12%5%7%7%46%5%6%8%26%
2405
11th to 20thNight
10%13%5%9%8%46%5%6%7%27%
2636
21st to endNight
9%14%6%8%9%46%6%6%7%26%
2806
December1st to 10thNight
9%16%7%10%8%5%6%5%6%6%22%
2850
11th to 20thNight
10%16%8%13%11%6%5%5%5%5%17%
3510
21st to endNight
10%16%7%14%11%5%5%45%6%15%
5214

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
75%11%10%41
1336
11th to 20thDay
71%14%9%5%1
1440
21st to endDay
68%10%12%8%2
1584
February1st to 10thDay
70%10%10%6%31
1494
11th to 20thDay
61%18%11%7%2
1616
21st to endDay
65%11%9%9%5%1
1480
March1st to 10thDay
60%10%15%10%4
1800
11th to 20thDay
55%13%16%13%3
1956
21st to endDay
60%13%14%10%2
2202
April1st to 10thDay
57%12%14%14%3
2164
11th to 20thDay
57%10%12%16%5%
2310
21st to endDay
53%11%14%16%41
2340
May1st to 10thDay
44%10%18%21%6%
2340
11th to 20thDay
43%13%19%18%7%
2541
21st to endDay
53%10%18%13%4
2918
June1st to 10thDay
50%10%16%18%6%
2700
11th to 20thDay
50%11%14%18%6%1
2700
21st to endDay
30%10%18%26%15%1
2700
July1st to 10thDay
21%7%12%30%23%7%
2626
11th to 20thDay
18%7%12%25%29%9%
2571
21st to endDay
12%48%27%39%9%
2589
August1st to 10thDay
19%7%13%28%25%8%
2448
11th to 20thDay
20%7%14%31%24%3
2299
21st to endDay
27%8%13%28%21%4
2574
September1st to 10thDay
27%8%13%29%18%5%
2162
11th to 20thDay
33%10%16%24%15%2
1980
21st to endDay
38%11%19%22%9%1
1980
October1st to 10thDay
43%11%17%24%5%
1937
11th to 20thDay
47%10%20%18%5%
1692
21st to endDay
55%11%16%15%3
1782
November1st to 10thDay
65%11%13%8%3
1674
11th to 20thDay
63%14%14%5%4
1524
21st to endDay
64%15%12%7%2
1373
December1st to 10thDay
69%11%12%6%2
1330
11th to 20thDay
75%10%11%31
1684
21st to endDay
73%13%7%6%1
2442
January1st to 10thNight
74%11%7%6%1
2836
11th to 20thNight
66%12%12%8%11
2542
21st to endNight
63%13%11%9%3
2772
February1st to 10thNight
62%13%12%9%41
2465
11th to 20thNight
58%14%16%9%3
2241
21st to endNight
57%13%12%14%41
1776
March1st to 10thNight
55%12%14%13%5%
2160
11th to 20thNight
51%14%15%17%3
2004
21st to endNight
53%16%16%11%4
2152
April1st to 10thNight
46%15%16%19%3
1796
11th to 20thNight
49%11%14%18%7%1
1601
21st to endNight
44%11%18%19%6%1
1620
May1st to 10thNight
40%14%16%22%8%
1620
11th to 20thNight
38%12%17%23%9%
1354
21st to endNight
49%10%19%16%7%
1358
June1st to 10thNight
44%10%16%21%9%
1260
11th to 20thNight
45%12%14%21%7%1
1260
21st to endNight
27%8%16%30%18%2
1260
July1st to 10thNight
14%5%11%32%29%9%
1225
11th to 20thNight
14%411%27%30%13%
1262
21st to endNight
10%5%8%24%37%15%
1488
August1st to 10thNight
15%412%31%27%11%
1465
11th to 20thNight
16%7%12%34%24%6%
1602
21st to endNight
23%7%12%28%26%5%
1782
September1st to 10thNight
23%7%15%28%19%7%
1795
11th to 20thNight
28%8%13%30%18%3
1980
21st to endNight
32%9%21%22%13%3
1980
October1st to 10thNight
38%11%16%26%9%
2022
11th to 20thNight
39%12%19%23%7%
2263
21st to endNight
48%12%16%17%7%
2574
November1st to 10thNight
59%12%14%10%4
2405
11th to 20thNight
58%14%17%8%3
2636
21st to endNight
58%14%16%9%2
2806
December1st to 10thNight
65%12%13%9%2
2850
11th to 20thNight
70%13%12%5%1
3507
21st to endNight
69%15%9%6%1
5214

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
20%18%20%24%13%6%
180
11th to 20thDay
24%16%22%19%11%9%
160
21st to endDay
19%16%27%28%7%3
176
February1st to 10thDay
23%24%25%23%4
184
11th to 20thDay
15%25%24%26%8%1
272
21st to endDay
18%18%29%23%10%2
346
March1st to 10thDay
17%25%26%20%10%1
420
11th to 20thDay
18%18%24%23%14%3
420
21st to endDay
16%22%28%22%10%2
462
April1st to 10thDay
16%25%27%22%8%2
420
11th to 20thDay
20%24%28%16%11%1
412
21st to endDay
16%23%26%21%12%2
420
May1st to 10thDay
14%15%26%27%15%2
423
11th to 20thDay
19%11%21%26%19%4
522
21st to endDay
21%12%15%27%20%5%
679
June1st to 10thDay
16%14%24%23%19%4
630
11th to 20thDay
17%18%27%21%14%2
630
21st to endDay
9%9%23%26%27%5%
630
July1st to 10thDay
46%25%30%29%6%
621
11th to 20thDay
5%10%25%32%24%3
570
21st to endDay
28%24%36%24%6%
487
August1st to 10thDay
6%9%26%32%23%6%
447
11th to 20thDay
5%7%23%31%25%8%
437
21st to endDay
7%10%25%30%22%6%
495
September1st to 10thDay
9%11%30%25%20%6%
450
11th to 20thDay
9%13%24%27%18%8%
450
21st to endDay
12%16%27%24%16%6%
450
October1st to 10thDay
16%11%24%26%17%7%
407
11th to 20thDay
16%16%22%22%17%7%
270
21st to endDay
26%20%18%22%12%2
297
November1st to 10thDay
27%18%22%21%12%
270
11th to 20thDay
20%21%21%24%11%1
270
21st to endDay
17%18%22%22%17%2
201
December1st to 10thDay
25%23%14%17%16%5%
180
11th to 20thDay
23%20%20%27%9%1
180
21st to endDay
18%18%28%24%9%3
198
January1st to 10thNight
26%16%23%23%10%1
950
11th to 20thNight
22%15%21%27%13%2
734
21st to endNight
21%13%23%33%9%1
792
February1st to 10thNight
22%18%22%28%9%1
720
11th to 20thNight
20%18%22%31%9%1
704
21st to endNight
15%14%25%32%14%1
592
March1st to 10thNight
16%14%23%33%12%1
720
11th to 20thNight
14%16%22%31%16%1
720
21st to endNight
14%15%22%33%14%2
792
April1st to 10thNight
15%12%22%35%16%1
716
11th to 20thNight
15%13%28%31%13%
533
21st to endNight
17%10%26%30%16%1
540
May1st to 10thNight
8%12%23%36%19%1
540
11th to 20thNight
13%5%16%37%28%1
366
21st to endNight
19%6%16%28%28%3
389
June1st to 10thNight
15%8%18%34%22%4
360
11th to 20thNight
17%10%23%29%21%1
360
21st to endNight
7%315%41%31%3
360
July1st to 10thNight
3311%44%38%2
350
11th to 20thNight
5%312%51%27%1
348
21st to endNight
3111%45%38%2
394
August1st to 10thNight
5%48%39%42%3
399
11th to 20thNight
5%211%39%37%6%
534
21st to endNight
7%413%41%35%1
594
September1st to 10thNight
6%413%43%31%4
692
11th to 20thNight
9%412%34%35%6%
720
21st to endNight
11%7%13%37%28%4
720
October1st to 10thNight
12%8%16%41%21%2
720
11th to 20thNight
13%10%17%36%22%3
720
21st to endNight
20%11%22%31%15%1
792
November1st to 10thNight
24%15%20%31%9%1
740
11th to 20thNight
24%17%21%27%11%
926
21st to endNight
19%15%19%33%13%1
950
December1st to 10thNight
20%14%19%30%15%2
950
11th to 20thNight
21%15%21%33%9%1
950
21st to endNight
24%15%23%28%10%1
1045
Page generated at 2024-01-08 09:14:18. Version ac07

Copyright 2024 Attilla Danko


Kalispell Clear Sky Chart |Charts Home