Brainerd
Clear Sky Chart
History

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

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 Type	Minimum conditions for hour to be usable				Out of hours
	Clear of Clouds	Transparency	Seeing	Sky Brightness
Planetary:	50%	(no limit)	Average	(no limit)	Nighttime Hours
Deep Sky:	70%	Average	(no limit)	5.9	Nighttime Hours
CCD Imaging:	70%	Below Average	Poor	(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

By Month

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 Forecast	Data Points
Cloud Cover	Day	13% 9% 3 8% 5% 5% 5% 4 6% 7% 37%	101852
	Night	12% 10% 4 9% 5% 4 4 4 5% 6% 37%	97401
Transparency	Day	46% 6% 13% 24% 10% 1	105448
	Night	46% 6% 12% 24% 11% 1	101946
Seeing	Day	16% 9% 31% 27% 14% 4	16116
	Night	15% 8% 33% 31% 11% 1	25999

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
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	8% 17% 6% 15% 8% 5% 5% 3 5% 6% 23%	2218
	11th to 20th	Day	6% 10% 5% 15% 11% 9% 8% 7% 6% 5% 17%	2391
	21st to end	Day	6% 16% 11% 15% 9% 6% 4 4 5% 5% 19%	3135
February	1st to 10th	Day	9% 11% 5% 11% 8% 5% 5% 4 6% 6% 29%	1710
	11th to 20th	Day	7% 11% 4 9% 8% 6% 5% 3 7% 7% 33%	1664
	21st to end	Day	9% 12% 4 11% 7% 5% 5% 5% 4 8% 30%	1413
March	1st to 10th	Day	11% 12% 3 10% 5% 5% 5% 4 5% 6% 34%	3422
	11th to 20th	Day	9% 9% 4 10% 5% 4 4 3 6% 8% 39%	3480
	21st to end	Day	20% 13% 4 10% 5% 4 5% 3 4 6% 27%	3814
April	1st to 10th	Day	17% 11% 4 7% 5% 5% 4 3 5% 5% 34%	2275
	11th to 20th	Day	18% 13% 4 8% 4 4 4 3 5% 6% 31%	2352
	21st to end	Day	21% 10% 3 6% 5% 4 4 3 4 5% 33%	2470
May	1st to 10th	Day	18% 7% 3 7% 4 4 4 4 5% 7% 37%	4260
	11th to 20th	Day	15% 6% 2 6% 4 4 4 3 6% 7% 42%	4399
	21st to end	Day	18% 7% 3 7% 5% 4 5% 4 5% 7% 35%	4824
June	1st to 10th	Day	11% 6% 2 5% 5% 5% 5% 4 7% 8% 42%	2763
	11th to 20th	Day	16% 6% 3 7% 5% 4 4 4 6% 7% 39%	2850
	21st to end	Day	10% 6% 2 5% 5% 5% 6% 5% 8% 9% 40%	2850
July	1st to 10th	Day	8% 5% 2 6% 5% 6% 7% 5% 7% 9% 40%	4750
	11th to 20th	Day	6% 4 1 4 3 4 4 4 6% 9% 54%	4662
	21st to end	Day	7% 5% 1 5% 4 4 4 4 7% 10% 49%	4765
August	1st to 10th	Day	13% 5% 2 5% 4 4 4 4 6% 8% 45%	4104
	11th to 20th	Day	12% 6% 2 6% 5% 4 5% 3 5% 9% 43%	4041
	21st to end	Day	13% 7% 3 6% 4 4 4 4 5% 6% 44%	4439
September	1st to 10th	Day	10% 6% 2 6% 3 4 4 4 6% 9% 47%	2280
	11th to 20th	Day	11% 6% 2 6% 5% 4 5% 4 5% 8% 44%	2200
	21st to end	Day	16% 6% 2 6% 4 3 4 4 5% 7% 43%	2032
October	1st to 10th	Day	18% 9% 2 6% 4 3 4 3 5% 7% 39%	1900
	11th to 20th	Day	16% 13% 3 6% 5% 4 4 2 4 6% 37%	1900
	21st to end	Day	19% 11% 5% 8% 4 5% 4 3 4 5% 33%	2062
November	1st to 10th	Day	13% 13% 4 10% 5% 5% 4 3 5% 5% 32%	1567
	11th to 20th	Day	12% 15% 7% 14% 6% 4 4 3 3 5% 26%	1520
	21st to end	Day	13% 12% 5% 9% 6% 4 5% 4 7% 6% 28%	1520
December	1st to 10th	Day	10% 15% 6% 11% 8% 6% 6% 4 5% 5% 23%	1520
	11th to 20th	Day	10% 15% 6% 12% 7% 6% 5% 4 5% 5% 25%	1858
	21st to end	Day	22% 16% 5% 15% 6% 4 3 2 3 4 18%	2442
January	1st to 10th	Night	10% 11% 5% 15% 7% 5% 4 4 6% 6% 26%	4737
	11th to 20th	Night	6% 13% 4 14% 9% 8% 10% 5% 6% 7% 19%	4560
	21st to end	Night	8% 18% 10% 15% 6% 5% 5% 4 5% 5% 22%	4532
February	1st to 10th	Night	6% 10% 5% 11% 6% 6% 5% 4 6% 7% 34%	2470
	11th to 20th	Night	5% 11% 4 10% 6% 5% 4 4 6% 8% 37%	2403
	21st to end	Night	10% 12% 4 10% 6% 5% 5% 4 5% 7% 31%	2041
March	1st to 10th	Night	9% 9% 3 7% 5% 4 4 4 5% 7% 44%	3463
	11th to 20th	Night	9% 10% 3 10% 6% 6% 6% 4 5% 5% 38%	3480
	21st to end	Night	21% 14% 5% 11% 4 3 3 3 3 5% 27%	3817
April	1st to 10th	Night	16% 11% 3 7% 4 4 4 4 4 6% 36%	1905
	11th to 20th	Night	18% 12% 4 8% 3 3 4 3 4 4 37%	1777
	21st to end	Night	19% 10% 3 7% 4 4 3 3 5% 6% 36%	1710
May	1st to 10th	Night	16% 8% 3 7% 4 4 4 3 5% 6% 40%	2645
	11th to 20th	Night	15% 5% 2 5% 4 3 4 4 5% 7% 46%	2506
	21st to end	Night	17% 7% 3 5% 5% 4 4 4 6% 6% 38%	2743
June	1st to 10th	Night	11% 5% 1 5% 4 4 4 4 7% 8% 46%	1413
	11th to 20th	Night	9% 5% 2 6% 4 5% 4 3 6% 9% 45%	1330
	21st to end	Night	10% 6% 2 7% 4 3 3 4 6% 8% 47%	1330
July	1st to 10th	Night	10% 4 2 5% 4 4 5% 5% 8% 10% 44%	2220
	11th to 20th	Night	5% 2 1 4 3 3 4 3 5% 7% 62%	2306
	21st to end	Night	4 4 2 5% 4 4 4 4 7% 8% 56%	2795
August	1st to 10th	Night	11% 5% 3 5% 4 4 4 3 5% 8% 49%	2836
	11th to 20th	Night	14% 5% 2 5% 3 3 4 3 6% 7% 50%	2798
	21st to end	Night	11% 6% 2 6% 4 3 4 4 5% 8% 47%	3224
September	1st to 10th	Night	9% 4 2 5% 3 3 4 3 6% 7% 53%	1900
	11th to 20th	Night	9% 5% 2 5% 4 4 4 3 5% 7% 53%	1976
	21st to end	Night	14% 5% 1 5% 3 3 3 2 4 6% 51%	2128
October	1st to 10th	Night	14% 8% 2 6% 4 3 4 3 5% 6% 44%	2280
	11th to 20th	Night	15% 11% 2 7% 4 4 4 3 5% 6% 39%	2280
	21st to end	Night	18% 11% 3 8% 4 4 4 3 5% 5% 34%	2534
November	1st to 10th	Night	13% 11% 4 8% 6% 4 4 4 5% 6% 35%	2731
	11th to 20th	Night	14% 12% 6% 12% 6% 4 4 3 5% 5% 30%	2667
	21st to end	Night	12% 10% 4 9% 7% 4 5% 4 6% 6% 33%	2660
December	1st to 10th	Night	10% 12% 6% 11% 9% 6% 5% 5% 5% 6% 24%	2660
	11th to 20th	Night	11% 14% 6% 12% 7% 6% 5% 5% 5% 6% 25%	3319
	21st to end	Night	22% 18% 5% 12% 6% 5% 3 2 4 4 19%	5225

Transparency (when cloud cover <= 30%)
Color Meanings: Too cloudy to forecast Poor Below Average Average Above average Transparent
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	62% 5% 9% 18% 5%	2219
	11th to 20th	Day	65% 6% 8% 16% 5%	2391
	21st to end	Day	65% 6% 9% 14% 5%	3135
February	1st to 10th	Day	53% 5% 10% 21% 10% 1	1710
	11th to 20th	Day	50% 5% 13% 22% 8% 1	1673
	21st to end	Day	52% 7% 10% 18% 12% 1	1413
March	1st to 10th	Day	49% 7% 12% 23% 9%	3422
	11th to 20th	Day	43% 5% 14% 28% 9%	3480
	21st to end	Day	59% 5% 11% 20% 4	3814
April	1st to 10th	Day	52% 5% 9% 19% 13% 1	2275
	11th to 20th	Day	53% 5% 12% 18% 12% 1	2352
	21st to end	Day	53% 5% 10% 21% 10%	2470
May	1st to 10th	Day	45% 6% 13% 22% 13% 2	4298
	11th to 20th	Day	40% 6% 14% 27% 10% 3	4403
	21st to end	Day	45% 9% 13% 24% 8% 1	4837
June	1st to 10th	Day	36% 8% 17% 28% 10% 1	2763
	11th to 20th	Day	43% 7% 13% 22% 14% 1	2850
	21st to end	Day	37% 10% 16% 27% 9%	2850
July	1st to 10th	Day	40% 6% 19% 22% 13% 1	4676
	11th to 20th	Day	25% 6% 17% 37% 13% 1	4581
	21st to end	Day	30% 6% 18% 33% 13% 1	4615
August	1st to 10th	Day	36% 6% 14% 29% 13% 2	4090
	11th to 20th	Day	39% 5% 16% 31% 9%	4080
	21st to end	Day	41% 5% 15% 27% 11% 1	4438
September	1st to 10th	Day	33% 8% 14% 34% 11%	2280
	11th to 20th	Day	37% 10% 17% 28% 8% 1	2200
	21st to end	Day	40% 7% 12% 32% 9% 1	2032
October	1st to 10th	Day	35% 4 13% 31% 16% 1	3160
	11th to 20th	Day	44% 4 10% 23% 17% 2	3140
	21st to end	Day	51% 3 13% 25% 7%	3377
November	1st to 10th	Day	53% 6% 11% 19% 11% 1	1567
	11th to 20th	Day	60% 5% 11% 15% 8% 1	1520
	21st to end	Day	53% 8% 13% 17% 6% 2	1520
December	1st to 10th	Day	60% 7% 13% 15% 5%	1520
	11th to 20th	Day	60% 5% 13% 18% 4	1855
	21st to end	Day	70% 5% 6% 12% 6%	2442
January	1st to 10th	Night	57% 5% 11% 21% 6% 1	4737
	11th to 20th	Night	63% 6% 13% 13% 5% 1	4560
	21st to end	Night	65% 4 8% 17% 5% 1	4532
February	1st to 10th	Night	48% 5% 12% 22% 11% 1	2470
	11th to 20th	Night	44% 6% 13% 24% 11% 2	2404
	21st to end	Night	52% 6% 10% 20% 11% 2	2041
March	1st to 10th	Night	40% 6% 15% 23% 15% 2	3463
	11th to 20th	Night	46% 4 12% 23% 14%	3480
	21st to end	Night	61% 4 8% 18% 8% 1	3817
April	1st to 10th	Night	49% 5% 11% 19% 16% 1	1905
	11th to 20th	Night	51% 5% 7% 20% 17% 1	1777
	21st to end	Night	48% 6% 10% 20% 14% 2	1710
May	1st to 10th	Night	43% 7% 11% 25% 13% 2	2672
	11th to 20th	Night	38% 6% 10% 26% 17% 3	2507
	21st to end	Night	44% 9% 12% 22% 13% 1	2751
June	1st to 10th	Night	34% 8% 17% 28% 10% 2	1413
	11th to 20th	Night	34% 7% 17% 24% 16% 2	1330
	21st to end	Night	34% 7% 15% 29% 12% 2	1330
July	1st to 10th	Night	34% 7% 20% 24% 14% 1	2185
	11th to 20th	Night	21% 6% 14% 41% 16% 3	2264
	21st to end	Night	26% 5% 18% 34% 15% 2	2706
August	1st to 10th	Night	34% 5% 14% 29% 15% 4	2826
	11th to 20th	Night	34% 5% 14% 34% 11% 1	2825
	21st to end	Night	36% 6% 17% 29% 11% 1	3224
September	1st to 10th	Night	29% 6% 15% 34% 14% 1	1900
	11th to 20th	Night	31% 6% 17% 34% 12%	1976
	21st to end	Night	35% 5% 11% 35% 14%	2128
October	1st to 10th	Night	29% 3 7% 37% 20% 4	3800
	11th to 20th	Night	40% 4 10% 25% 19% 1	3779
	21st to end	Night	48% 4 14% 23% 11%	4170
November	1st to 10th	Night	49% 6% 11% 23% 10% 1	2731
	11th to 20th	Night	54% 7% 13% 16% 9% 1	2667
	21st to end	Night	49% 7% 16% 20% 6% 2	2660
December	1st to 10th	Night	59% 7% 12% 16% 5% 1	2660
	11th to 20th	Night	59% 6% 12% 16% 6% 2	3321
	21st to end	Night	69% 4 8% 13% 5%	5225

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
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	12% 9% 34% 33% 10% 3	270
	11th to 20th	Day	16% 10% 31% 35% 7%	270
	21st to end	Day	11% 8% 39% 23% 16% 3	297
February	1st to 10th	Day	14% 16% 40% 22% 7%	270
	11th to 20th	Day	15% 17% 39% 20% 8% 1	270
	21st to end	Day	15% 9% 41% 32% 2	225
March	1st to 10th	Day	17% 13% 37% 24% 7% 1	270
	11th to 20th	Day	16% 7% 36% 27% 10% 3	270
	21st to end	Day	22% 12% 30% 20% 13% 2	297
April	1st to 10th	Day	22% 14% 30% 25% 8% 1	455
	11th to 20th	Day	26% 12% 27% 23% 11% 1	550
	21st to end	Day	25% 10% 28% 23% 12% 1	650
May	1st to 10th	Day	21% 13% 31% 22% 10% 2	653
	11th to 20th	Day	19% 11% 28% 26% 12% 3	675
	21st to end	Day	18% 8% 27% 30% 14% 3	734
June	1st to 10th	Day	12% 6% 30% 30% 18% 4	680
	11th to 20th	Day	18% 9% 35% 26% 10% 2	680
	21st to end	Day	12% 8% 33% 28% 15% 5%	680
July	1st to 10th	Day	7% 5% 22% 28% 28% 9%	671
	11th to 20th	Day	9% 6% 28% 29% 19% 9%	668
	21st to end	Day	6% 5% 24% 33% 24% 8%	739
August	1st to 10th	Day	11% 4 23% 31% 25% 6%	676
	11th to 20th	Day	11% 5% 21% 32% 24% 6%	665
	21st to end	Day	12% 7% 27% 29% 19% 5%	694
September	1st to 10th	Day	10% 7% 30% 32% 17% 4	490
	11th to 20th	Day	10% 6% 29% 32% 17% 6%	410
	21st to end	Day	21% 10% 30% 24% 11% 4	300
October	1st to 10th	Day	22% 10% 28% 24% 11% 5%	300
	11th to 20th	Day	16% 14% 39% 24% 5% 1	300
	21st to end	Day	25% 15% 37% 15% 6% 1	330
November	1st to 10th	Day	18% 11% 37% 24% 9% 1	300
	11th to 20th	Day	19% 13% 44% 21% 3	270
	21st to end	Day	23% 10% 41% 22% 4	270
December	1st to 10th	Day	14% 10% 43% 23% 9% 1	270
	11th to 20th	Day	18% 14% 38% 28% 2	270
	21st to end	Day	26% 10% 34% 25% 4 1	297
January	1st to 10th	Night	11% 11% 37% 29% 9% 2	950
	11th to 20th	Night	15% 10% 36% 31% 8% 1	950
	21st to end	Night	16% 10% 38% 28% 8% 1	1045
February	1st to 10th	Night	10% 10% 38% 31% 9% 1	950
	11th to 20th	Night	10% 11% 43% 26% 9% 1	929
	21st to end	Night	16% 9% 36% 29% 10% 1	785
March	1st to 10th	Night	15% 10% 36% 28% 8% 2	603
	11th to 20th	Night	15% 11% 42% 26% 6%	570
	21st to end	Night	22% 8% 29% 28% 11% 3	627
April	1st to 10th	Night	19% 10% 36% 29% 5% 1	570
	11th to 20th	Night	24% 7% 29% 30% 9% 1	563
	21st to end	Night	22% 7% 32% 30% 9% 1	570
May	1st to 10th	Night	19% 8% 35% 29% 8% 1	570
	11th to 20th	Night	16% 8% 32% 34% 9% 1	561
	21st to end	Night	14% 8% 27% 37% 13%	617
June	1st to 10th	Night	13% 4 29% 39% 14% 1	570
	11th to 20th	Night	12% 4 33% 41% 9%	570
	21st to end	Night	12% 5% 24% 41% 18% 1	570
July	1st to 10th	Night	6% 2 22% 44% 25% 2	555
	11th to 20th	Night	7% 3 27% 43% 19% 1	552
	21st to end	Night	5% 2 23% 44% 23% 3	624
August	1st to 10th	Night	8% 2 19% 48% 20% 3	567
	11th to 20th	Night	13% 2 19% 38% 25% 2	564
	21st to end	Night	10% 5% 25% 36% 22% 2	627
September	1st to 10th	Night	10% 6% 22% 43% 18% 2	570
	11th to 20th	Night	11% 6% 30% 33% 19% 2	570
	21st to end	Night	16% 7% 32% 29% 14% 1	608
October	1st to 10th	Night	18% 10% 31% 28% 12% 1	760
	11th to 20th	Night	21% 9% 36% 28% 5% 1	760
	21st to end	Night	22% 11% 34% 27% 6%	849
November	1st to 10th	Night	19% 9% 33% 31% 9%	975
	11th to 20th	Night	19% 13% 35% 25% 8% 1	953
	21st to end	Night	17% 13% 40% 24% 6%	950
December	1st to 10th	Night	16% 11% 36% 29% 7% 1	950
	11th to 20th	Night	19% 11% 36% 26% 7% 1	950
	21st to end	Night	25% 10% 36% 23% 6% 1	1045

Page generated at 2024-11-08 05:44:49. Version ac07

Copyright © 2024 Attilla Danko.