Meeteetse
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Meeteetse clear sky chart from 2005-11-05 to 2017-12-04.

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
50%
16443
22%
47878
14%
16401
57%
16401
36%
27301

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
41%
899
21%
2506
12%
895
49%
895
35%
1442
January16th to endNight
45%
774
25%
2502
16%
774
58%
774
35%
1334
February1st to 15thNight
40%
698
18%
2288
12%
698
50%
698
28%
1318
February16th to endNight
36%
632
19%
2028
10%
632
48%
632
26%
1188
March1st to 15thNight
41%
720
21%
1986
10%
720
51%
720
37%
1149
March16th to endNight
39%
768
17%
2112
8%
768
46%
768
31%
1325
April1st to 15thNight
38%
545
15%
1804
9%
545
46%
545
23%
1127
April16th to endNight
40%
540
15%
1657
11%
540
44%
540
23%
1085
May1st to 15thNight
46%
540
15%
1542
9%
540
50%
540
29%
970
May16th to endNight
50%
563
14%
1498
11%
561
53%
561
26%
1021
June1st to 15thNight
55%
540
15%
1440
8%
540
59%
540
35%
864
June16th to endNight
65%
540
23%
1440
16%
540
70%
540
56%
719
July1st to 15thNight
74%
510
20%
1360
16%
510
77%
510
54%
704
July16th to endNight
76%
564
28%
1490
25%
531
79%
531
61%
697
August1st to 15thNight
78%
539
27%
1611
24%
536
81%
536
49%
803
August16th to endNight
73%
573
35%
1782
30%
573
77%
573
52%
843
September1st to 15thNight
61%
540
29%
1800
24%
540
70%
540
42%
903
September16th to endNight
65%
704
30%
1995
24%
704
69%
704
46%
1074
October1st to 15thNight
50%
720
22%
2160
14%
720
55%
720
32%
1306
October16th to endNight
53%
768
30%
2304
19%
768
64%
768
39%
1258
November1st to 15thNight
43%
911
24%
2579
15%
911
51%
911
37%
1466
November16th to endNight
41%
975
25%
2730
13%
975
51%
975
37%
1549
December1st to 15thNight
42%
920
17%
2576
9%
920
48%
920
35%
1535
December16th to endNight
41%
960
22%
2688
12%
960
51%
960
32%
1621

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
5%5%24435%5%6%8%47%
48626
Night
342442445%8%53%
48056
TransparencyDay
32%9%15%23%15%5%
48307
Night
27%7%17%26%16%5%
47878
SeeingDay
9%12%33%28%12%3
6219
Night
5%8%30%36%16%3
16450

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 15thDay
2244245%8%9%54%
1435
16th to endDay
336%5%345%5%9%51%
1728
February1st to 15thDay
437%6%35%6%6%9%47%
1575
16th to endDay
6%46%7%36%5%7%9%42%
1446
March1st to 15thDay
14245%345%7%12%48%
1971
16th to endDay
5%9%36%5%345%7%9%37%
2112
April1st to 15thDay
5%10%37%5%3446%10%37%
2142
16th to endDay
9%11%46%436%47%8%32%
2301
May1st to 15thDay
10%10%25%5%345%48%38%
2408
16th to endDay
15%7%245%36%6%7%10%29%
2616
June1st to 15thDay
6%6%246%26%5%7%9%41%
2520
16th to endDay
22123245%8%8%58%
2520
July1st to 15thDay
3314437%7%6%8%49%
2520
16th to endDay
4213425%6%6%8%54%
2573
August1st to 15thDay
43145%36%7%7%8%46%
2340
16th to endDay
4313425%5%5%7%55%
2419
September1st to 15thDay
7%41433435%5%56%
2160
16th to endDay
8%312333346%57%
1962
October1st to 15thDay
10%8%2332435%8%48%
1800
16th to endDay
45%1343445%8%54%
1920
November1st to 15thDay
13235%245%6%9%54%
1596
16th to endDay
1435%3245%6%9%52%
1560
December1st to 15thDay
1426%5%2445%9%51%
1466
16th to endDay
5%34425%5%7%10%49%
1536
January1st to 15thNight
236%5%25%46%9%53%
2506
16th to endNight
1425%5%24448%56%
2502
February1st to 15thNight
436%5%345%5%8%49%
2277
16th to endNight
15%37%5%25%45%7%50%
2028
March1st to 15thNight
1415%5%2447%11%50%
1986
16th to endNight
5%5%25%5%3446%10%46%
2112
April1st to 15thNight
48%35%5%35%5%6%7%44%
1804
16th to endNight
8%9%35%5%345%5%7%40%
1657
May1st to 15thNight
10%7%24423448%47%
1541
16th to endNight
15%5%25%42446%9%39%
1497
June1st to 15thNight
5%4135%25%5%6%8%50%
1440
16th to endNight
212213247%69%
1440
July1st to 15thNight
1122145%8%11%61%
1440
16th to endNight
11221345%6%70%
1592
August1st to 15thNight
2133145%6%8%60%
1620
16th to endNight
3211223346%68%
1782
September1st to 15thNight
5%41231345%6%60%
1800
16th to endNight
6%413222346%62%
1995
October1st to 15thNight
8%8%23423446%50%
2160
16th to endNight
342441345%7%57%
2304
November1st to 15thNight
2425%4235%5%9%54%
2579
16th to endNight
15%244235%7%10%51%
2730
December1st to 15thNight
1426%435%6%7%9%49%
2576
16th to endNight
15%26%5%345%6%10%47%
2688

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
22%10%26%26%11%3
1436
16th to endDay
28%6%21%25%14%3
1728
February1st to 15thDay
32%10%20%26%7%2
1575
16th to endDay
37%10%17%22%8%3
1446
March1st to 15thDay
27%10%20%28%12%1
1971
16th to endDay
41%9%17%24%6%
2112
April1st to 15thDay
42%10%15%22%8%
2142
16th to endDay
48%9%13%23%4
2301
May1st to 15thDay
44%9%12%24%9%
2408
16th to endDay
47%11%15%18%6%
2620
June1st to 15thDay
36%10%16%21%12%2
2520
16th to endDay
19%9%10%26%22%11%
2520
July1st to 15thDay
28%9%11%21%18%11%
2371
16th to endDay
23%7%9%16%25%18%
2413
August1st to 15thDay
28%11%11%17%19%11%
2325
16th to endDay
26%6%9%19%24%13%
2419
September1st to 15thDay
28%6%7%20%27%9%
2160
16th to endDay
27%6%10%27%24%3
1962
October1st to 15thDay
34%7%13%27%15%2
1800
16th to endDay
27%7%15%28%18%3
1920
November1st to 15thDay
23%8%19%23%21%3
1596
16th to endDay
26%8%21%27%14%2
1560
December1st to 15thDay
27%9%25%25%10%
1466
16th to endDay
28%8%18%29%13%2
1536
January1st to 15thNight
24%9%23%28%12%2
2506
16th to endNight
26%5%20%26%16%4
2502
February1st to 15thNight
30%8%20%28%9%2
2288
16th to endNight
32%7%18%24%13%3
2028
March1st to 15thNight
26%6%21%29%14%1
1986
16th to endNight
33%7%19%29%9%1
2112
April1st to 15thNight
36%10%19%22%10%1
1804
16th to endNight
41%7%16%26%7%
1657
May1st to 15thNight
36%6%16%28%11%
1542
16th to endNight
40%8%20%20%8%1
1498
June1st to 15thNight
28%8%21%24%14%2
1440
16th to endNight
15%5%11%28%27%11%
1440
July1st to 15thNight
15%7%13%28%21%13%
1360
16th to endNight
12%5%6%21%30%24%
1490
August1st to 15thNight
17%7%9%25%25%13%
1611
16th to endNight
17%5%9%25%27%15%
1782
September1st to 15thNight
23%5%8%23%28%10%
1800
16th to endNight
23%410%28%27%4
1995
October1st to 15thNight
33%6%14%29%11%4
2160
16th to endNight
25%6%13%30%19%4
2304
November1st to 15thNight
25%7%17%26%17%4
2579
16th to endNight
25%7%20%28%16%2
2730
December1st to 15thNight
27%9%24%25%11%
2576
16th to endNight
30%7%18%27%13%2
2688

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
2127%33%25%10%
90
16th to endDay
2129%41%21%4
96
February1st to 15thDay
223%37%34%2
90
16th to endDay
429%29%19%14%1
81
March1st to 15thDay
429%43%16%4
261
16th to endDay
14%26%38%16%3
288
April1st to 15thDay
11%23%42%18%31
269
16th to endDay
24%21%34%13%4
270
May1st to 15thDay
16%13%32%22%11%3
365
16th to endDay
22%8%24%24%15%4
517
June1st to 15thDay
7%13%31%29%15%3
495
16th to endDay
410%35%31%14%3
495
July1st to 15thDay
6%428%32%23%5%
475
16th to endDay
5%7%34%32%17%2
432
August1st to 15thDay
5%5%43%33%9%2
315
16th to endDay
7%434%38%9%4
332
September1st to 15thDay
10%10%38%30%6%3
315
16th to endDay
11%12%31%31%11%2
288
October1st to 15thDay
11%11%34%31%8%1
135
16th to endDay
417%33%33%10%1
144
November1st to 15thDay
49%25%31%20%8%
135
16th to endDay
10%16%29%39%4
135
December1st to 15thDay
46%41%38%11%
100
16th to endDay
47%27%44%11%5%
96
January1st to 15thNight
113%37%32%11%3
900
16th to endNight
39%34%37%13%1
774
February1st to 15thNight
211%36%36%10%2
704
16th to endNight
313%35%34%10%2
632
March1st to 15thNight
411%35%34%13%1
720
16th to endNight
7%12%34%34%9%1
768
April1st to 15thNight
8%9%37%33%10%
545
16th to endNight
11%10%32%30%11%2
540
May1st to 15thNight
14%7%27%31%17%1
540
16th to endNight
18%5%20%31%21%1
563
June1st to 15thNight
6%9%25%39%18%1
540
16th to endNight
2326%42%23%1
540
July1st to 15thNight
2215%43%33%1
510
16th to endNight
1117%47%29%2
564
August1st to 15thNight
313%43%36%1
539
16th to endNight
4116%41%31%5%
573
September1st to 15thNight
7%223%38%21%6%
540
16th to endNight
9%317%38%22%9%
704
October1st to 15thNight
13%327%34%15%5%
720
16th to endNight
46%30%38%12%7%
768
November1st to 15thNight
311%35%34%13%1
911
16th to endNight
410%38%36%9%1
975
December1st to 15thNight
39%39%36%10%1
920
16th to endNight
49%35%37%10%2
960
Page generated at 2017-12-05 08:18:59. Version ac04

Copyright 2017 A. Danko


Meeteetse Clear Sky Chart |Charts Home