Tulelake
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Tulelake clear sky chart from 2005-11-06 to 2024-03-08.

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
59%
23189
21%
80617
21%
23105
63%
23105
29%
48469

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
44%
749
9%
4384
10%
736
48%
736
10%
3084
January11th to 20thNight
48%
755
13%
4365
16%
740
51%
740
11%
3129
January21st to endNight
50%
831
12%
4481
21%
814
53%
814
12%
3286
February1st to 10thNight
50%
760
18%
2470
16%
760
54%
760
24%
1606
February11th to 20thNight
48%
740
17%
2366
15%
740
53%
740
25%
1519
February21st to endNight
47%
628
18%
1884
15%
628
53%
628
25%
1235
March1st to 10thNight
38%
750
13%
2199
11%
750
41%
750
19%
1585
March11th to 20thNight
50%
720
18%
1980
14%
720
53%
720
27%
1325
March21st to endNight
41%
792
12%
2098
7%
792
44%
792
22%
1498
April1st to 10thNight
47%
720
18%
1800
10%
720
49%
720
27%
1251
April11th to 20thNight
46%
711
20%
1779
10%
711
49%
711
32%
1177
April21st to endNight
54%
720
18%
1800
9%
720
57%
720
38%
1120
May1st to 10thNight
56%
443
23%
1523
18%
443
63%
443
37%
806
May11th to 20thNight
58%
354
21%
1416
22%
354
64%
354
27%
763
May21st to endNight
58%
389
17%
1552
19%
388
65%
388
26%
862
June1st to 10thNight
62%
360
17%
1440
22%
360
67%
360
29%
755
June11th to 20thNight
61%
360
24%
1440
29%
360
72%
360
40%
638
June21st to endNight
79%
360
30%
1440
42%
360
84%
360
56%
538
July1st to 10thNight
84%
350
29%
1400
41%
350
89%
350
60%
502
July11th to 20thNight
85%
348
36%
1392
48%
348
90%
348
65%
470
July21st to endNight
89%
438
39%
1530
46%
414
91%
414
68%
545
August1st to 10thNight
89%
537
34%
1602
31%
534
91%
534
62%
719
August11th to 20thNight
88%
583
38%
1651
29%
583
90%
583
73%
712
August21st to endNight
83%
792
41%
1980
25%
792
85%
792
76%
910
September1st to 10thNight
83%
720
43%
1800
26%
720
86%
720
77%
820
September11th to 20thNight
79%
720
39%
1800
28%
720
81%
720
62%
928
September21st to endNight
73%
720
36%
2030
31%
720
77%
720
54%
1003
October1st to 10thNight
69%
720
27%
2160
26%
720
74%
720
49%
1093
October11th to 20thNight
68%
720
31%
2160
32%
720
72%
720
47%
1088
October21st to endNight
65%
792
28%
2398
28%
792
69%
792
41%
1307
November1st to 10thNight
56%
740
21%
2405
21%
740
60%
740
26%
1509
November11th to 20thNight
53%
760
16%
2563
16%
760
57%
760
23%
1666
November21st to endNight
58%
760
15%
2660
16%
760
61%
760
25%
1629
December1st to 10thNight
53%
760
18%
2660
20%
760
56%
760
24%
1672
December11th to 20thNight
47%
760
14%
3208
14%
759
49%
759
13%
2321
December21st to endNight
36%
827
9%
4801
14%
817
40%
817
9%
3398

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
8%7%35%5%3445%7%51%
78583
Night
10%8%35%5%3445%7%48%
81012
TransparencyDay
33%6%11%20%19%12%
78289
Night
35%7%12%21%17%8%
80827
SeeingDay
11%10%20%25%22%11%
13925
Night
10%6%18%38%25%3
23223

By Month

Percentage Cloud Cover SW (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%16%6%8%8%46%5%5%7%24%
2539
11th to 20thDay
21%20%5%8%5%24346%22%
2576
21st to endDay
20%12%37%5%34447%30%
3146
February1st to 10thDay
10%10%36%6%36%5%6%8%37%
1710
11th to 20thDay
9%10%46%6%45%5%5%8%38%
1703
21st to endDay
8%12%48%7%46%5%5%7%35%
1570
March1st to 10thDay
10%14%5%7%6%45%5%5%8%31%
1919
11th to 20thDay
11%11%45%6%45%5%48%37%
1980
21st to endDay
9%12%5%8%7%45%6%5%7%32%
2258
April1st to 10thDay
10%9%49%7%46%5%5%6%36%
2160
11th to 20thDay
12%8%36%5%3445%7%43%
2129
21st to endDay
8%5%36%5%3445%8%50%
2160
May1st to 10thDay
7%5%25%43445%7%53%
2433
11th to 20thDay
9%6%25%5%3435%7%51%
2477
21st to endDay
9%7%25%5%345%5%7%46%
2723
June1st to 10thDay
8%4245%35%6%6%7%50%
2520
11th to 20thDay
3313423347%66%
2520
21st to endDay
422212336%74%
2520
July1st to 10thDay
222222345%76%
2520
11th to 20thDay
1111212345%79%
2520
21st to endDay
221122335%477%
2693
August1st to 10thDay
21123245%5%6%70%
2328
11th to 20thDay
2111112345%79%
2248
21st to endDay
21211112484%
2376
September1st to 10thDay
111222223481%
2160
11th to 20thDay
4213323346%69%
2160
21st to endDay
4323413347%66%
1927
October1st to 10thDay
7%414413436%63%
1800
11th to 20thDay
9%42332345%8%58%
1800
21st to endDay
9%6%25%5%3445%7%51%
1957
November1st to 10thDay
13%8%35%5%35%348%40%
1674
11th to 20thDay
13%8%46%6%35%6%7%8%34%
1615
21st to endDay
9%8%38%6%45%5%5%8%38%
1520
December1st to 10thDay
11%10%36%5%45%6%6%8%37%
1520
11th to 20thDay
19%10%47%7%36%5%7%9%23%
1928
21st to endDay
13%11%6%10%9%5%5%6%6%7%23%
2794
January1st to 10thNight
10%12%5%8%8%5%7%6%6%8%25%
4406
11th to 20thNight
17%17%47%6%45%5%5%6%27%
4384
21st to endNight
20%12%48%6%45%5%46%28%
4521
February1st to 10thNight
9%9%35%6%46%5%5%8%41%
2470
11th to 20thNight
11%10%35%5%35%5%5%7%42%
2364
21st to endNight
8%8%46%6%45%6%5%7%40%
1884
March1st to 10thNight
11%14%5%7%7%35%45%6%33%
2199
11th to 20thNight
11%10%35%435%5%6%12%36%
1980
21st to endNight
11%11%46%7%36%5%5%7%37%
2098
April1st to 10thNight
11%9%45%6%35%46%7%39%
1800
11th to 20thNight
9%9%36%5%33447%47%
1779
21st to endNight
10%5%2442345%8%52%
1800
May1st to 10thNight
7%424434445%58%
1523
11th to 20thNight
8%6%245%245%7%8%49%
1416
21st to endNight
10%5%24435%45%6%52%
1552
June1st to 10thNight
10%5%2443435%8%52%
1440
11th to 20thNight
5%313323345%68%
1440
21st to endNight
331231323475%
1440
July1st to 10thNight
1112223435%77%
1440
11th to 20thNight
121221223381%
1440
21st to endNight
11121234480%
1620
August1st to 10thNight
1212334345%74%
1611
11th to 20thNight
1211213245%79%
1651
21st to endNight
22121222482%
1980
September1st to 10thNight
21121123483%
1800
11th to 20thNight
4212223346%72%
1800
21st to endNight
5%313322336%69%
2030
October1st to 10thNight
5%41432334468%
2160
11th to 20thNight
7%413323346%63%
2160
21st to endNight
8%5%2433445%8%57%
2398
November1st to 10thNight
12%8%25%6%445%6%8%43%
2405
11th to 20thNight
14%7%25%5%46%5%6%10%38%
2563
21st to endNight
9%8%35%5%445%6%8%43%
2660
December1st to 10thNight
13%8%25%43446%8%41%
2660
11th to 20thNight
18%10%46%7%45%6%6%8%28%
3276
21st to endNight
14%11%49%9%5%6%5%5%7%26%
4862

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
53%13%14%15%41
2539
11th to 20thDay
63%7%8%12%6%3
2576
21st to endDay
51%9%14%18%6%2
3146
February1st to 10thDay
42%8%17%21%11%1
1710
11th to 20thDay
43%7%14%23%12%2
1712
21st to endDay
46%7%16%18%10%3
1570
March1st to 10thDay
49%10%12%19%9%2
1919
11th to 20thDay
44%7%15%17%17%1
1980
21st to endDay
49%8%17%16%8%2
2258
April1st to 10thDay
48%6%13%17%13%3
2160
11th to 20thDay
39%5%13%23%15%5%
2132
21st to endDay
32%6%16%25%18%3
2160
May1st to 10thDay
29%5%11%26%23%5%
2433
11th to 20thDay
34%5%12%25%20%5%
2480
21st to endDay
36%6%14%25%16%3
2724
June1st to 10thDay
31%7%13%26%19%4
2520
11th to 20thDay
19%49%28%32%8%
2520
21st to endDay
14%36%24%32%21%
2520
July1st to 10thDay
12%35%19%27%34%
2451
11th to 20thDay
9%3417%29%37%
2445
21st to endDay
12%3411%28%42%
2543
August1st to 10thDay
13%5%7%19%29%28%
2312
11th to 20thDay
9%25%18%33%33%
2248
21st to endDay
9%2317%38%32%
2376
September1st to 10thDay
9%3415%29%41%
2160
11th to 20thDay
17%48%19%31%21%
2160
21st to endDay
18%48%22%27%20%
1927
October1st to 10thDay
25%411%19%24%17%
1800
11th to 20thDay
25%410%25%26%10%
1800
21st to endDay
31%7%11%19%21%10%
1957
November1st to 10thDay
42%7%11%22%15%4
1674
11th to 20thDay
44%8%17%16%14%1
1615
21st to endDay
42%7%13%19%17%3
1520
December1st to 10thDay
43%10%12%19%13%3
1520
11th to 20thDay
54%9%16%15%6%
1928
21st to endDay
53%15%12%15%41
2794
January1st to 10thNight
48%14%18%15%41
4406
11th to 20thNight
53%10%10%15%8%4
4384
21st to endNight
55%9%11%16%8%2
4521
February1st to 10thNight
41%8%14%23%12%2
2470
11th to 20thNight
40%7%15%22%13%2
2366
21st to endNight
40%8%17%20%12%3
1884
March1st to 10thNight
50%7%13%17%11%2
2199
11th to 20thNight
41%8%15%21%15%
1980
21st to endNight
46%8%17%19%9%1
2098
April1st to 10thNight
42%7%16%21%11%3
1800
11th to 20thNight
38%6%15%22%14%5%
1779
21st to endNight
31%7%20%27%14%3
1800
May1st to 10thNight
27%6%14%28%22%3
1523
11th to 20thNight
32%6%15%26%17%4
1416
21st to endNight
34%7%18%28%12%2
1552
June1st to 10thNight
31%6%16%31%14%2
1440
11th to 20thNight
20%6%10%32%27%5%
1440
21st to endNight
13%38%29%32%14%
1440
July1st to 10thNight
10%48%21%31%26%
1400
11th to 20thNight
10%25%17%33%34%
1392
21st to endNight
9%25%14%32%37%
1530
August1st to 10thNight
13%47%24%29%22%
1602
11th to 20thNight
8%36%21%36%26%
1651
21st to endNight
8%25%20%35%29%
1980
September1st to 10thNight
7%2417%28%41%
1800
11th to 20thNight
15%47%21%32%21%
1800
21st to endNight
18%48%23%23%24%
2030
October1st to 10thNight
21%5%10%21%27%17%
2160
11th to 20thNight
21%5%12%25%25%12%
2160
21st to endNight
26%6%15%22%19%12%
2398
November1st to 10thNight
38%8%12%20%17%4
2405
11th to 20thNight
41%9%15%18%15%1
2563
21st to endNight
37%8%16%18%17%4
2660
December1st to 10thNight
38%9%13%22%16%2
2660
11th to 20thNight
52%9%10%19%9%1
3276
21st to endNight
51%12%11%18%6%1
4862

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
24%15%25%24%8%4
180
11th to 20thDay
23%12%21%22%11%10%
203
21st to endDay
18%11%18%24%21%8%
407
February1st to 10thDay
14%14%21%24%19%6%
370
11th to 20thDay
16%16%22%24%16%5%
383
21st to endDay
16%13%25%30%12%4
382
March1st to 10thDay
21%17%29%21%11%2
449
11th to 20thDay
18%15%25%23%18%2
420
21st to endDay
21%16%23%26%12%2
462
April1st to 10thDay
16%18%26%23%12%5%
420
11th to 20thDay
20%16%23%22%13%8%
412
21st to endDay
9%17%26%23%18%8%
420
May1st to 10thDay
11%13%25%28%18%5%
423
11th to 20thDay
16%12%23%23%15%12%
448
21st to endDay
12%9%18%26%22%13%
485
June1st to 10thDay
8%12%20%24%22%15%
450
11th to 20thDay
6%16%24%22%22%10%
450
21st to endDay
26%17%28%28%18%
450
July1st to 10thDay
4319%31%28%14%
446
11th to 20thDay
1220%29%28%20%
444
21st to endDay
2214%29%32%22%
487
August1st to 10thDay
2117%27%30%23%
447
11th to 20thDay
2414%25%31%24%
437
21st to endDay
3416%29%30%18%
495
September1st to 10thDay
1420%23%36%16%
450
11th to 20thDay
5%7%19%27%25%17%
450
21st to endDay
6%7%20%27%30%9%
450
October1st to 10thDay
9%10%18%25%22%17%
450
11th to 20thDay
11%10%16%23%27%13%
450
21st to endDay
13%10%18%26%20%14%
472
November1st to 10thDay
17%9%16%31%18%9%
270
11th to 20thDay
13%7%19%25%29%8%
225
21st to endDay
12%7%17%29%27%7%
180
December1st to 10thDay
17%12%19%26%17%9%
180
11th to 20thDay
23%11%16%25%19%6%
180
21st to endDay
13%15%23%25%23%2
198
January1st to 10thNight
16%8%23%33%18%3
760
11th to 20thNight
15%9%22%31%19%3
760
21st to endNight
15%5%22%36%19%4
836
February1st to 10thNight
11%7%24%39%18%1
760
11th to 20thNight
15%8%22%35%18%2
744
21st to endNight
11%11%23%40%14%1
628
March1st to 10thNight
16%13%26%30%13%2
750
11th to 20thNight
16%8%19%36%19%2
720
21st to endNight
16%11%24%33%15%
792
April1st to 10thNight
13%10%23%36%17%1
720
11th to 20thNight
11%9%27%33%17%3
711
21st to endNight
11%9%23%36%20%2
720
May1st to 10thNight
8%6%26%39%21%1
443
11th to 20thNight
12%419%38%25%2
354
21st to endNight
11%420%41%24%1
389
June1st to 10thNight
10%416%43%27%1
360
11th to 20thNight
6%5%24%44%20%1
360
21st to endNight
4112%52%31%
360
July1st to 10thNight
2110%52%35%1
350
11th to 20thNight
219%54%34%
348
21st to endNight
15%51%40%3
438
August1st to 10thNight
11344%48%3
537
11th to 20thNight
216%42%44%5%
583
21st to endNight
2110%43%41%3
792
September1st to 10thNight
2211%42%41%3
720
11th to 20thNight
5%212%35%40%6%
720
21st to endNight
5%315%37%34%5%
720
October1st to 10thNight
6%218%38%32%4
720
11th to 20thNight
8%415%37%32%5%
720
21st to endNight
10%417%37%26%6%
792
November1st to 10thNight
13%6%17%41%19%5%
740
11th to 20thNight
15%7%21%36%20%2
760
21st to endNight
12%8%17%37%23%3
760
December1st to 10thNight
15%6%20%34%22%3
760
11th to 20thNight
17%10%18%34%20%2
760
21st to endNight
18%11%24%36%10%1
836
Page generated at 2024-03-05 04:23:59. Version ac07

Copyright © 2024 Attilla Danko.


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