Novi Community Sports Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Novi Community Sports Park clear sky chart from 2005-11-06 to 2025-05-26.

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	14% 10% 4 9% 5% 5% 5% 4 6% 7% 32%	113268
	Night	14% 11% 4 8% 5% 4 4 3 5% 6% 34%	116056
Transparency	Day	48% 6% 12% 20% 12% 1	116882
	Night	48% 6% 12% 21% 12% 1	120582
Seeing	Day	18% 13% 29% 22% 13% 5%	16128
	Night	19% 10% 29% 29% 11% 1	26290

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	12% 16% 6% 17% 7% 4 4 3 4 5% 23%	3617
	11th to 20th	Day	14% 15% 6% 18% 8% 9% 7% 3 5% 5% 10%	3620
	21st to end	Day	21% 18% 6% 12% 6% 4 5% 3 4 5% 15%	4377
February	1st to 10th	Day	14% 14% 6% 13% 8% 6% 5% 4 4 5% 22%	1800
	11th to 20th	Day	14% 13% 6% 12% 9% 6% 5% 3 5% 5% 23%	1901
	21st to end	Day	15% 15% 4 10% 6% 5% 4 4 4 6% 26%	1650
March	1st to 10th	Day	15% 13% 5% 11% 6% 4 4 3 4 5% 30%	4569
	11th to 20th	Day	12% 11% 4 8% 5% 4 4 4 5% 8% 35%	4980
	21st to end	Day	18% 14% 4 9% 5% 5% 4 3 5% 5% 28%	5465
April	1st to 10th	Day	16% 13% 4 7% 4 5% 5% 4 5% 7% 30%	2335
	11th to 20th	Day	16% 10% 3 7% 5% 5% 4 3 6% 6% 35%	2527
	21st to end	Day	17% 9% 3 8% 4 4 5% 3 5% 7% 35%	2600
May	1st to 10th	Day	17% 9% 3 7% 5% 6% 5% 3 5% 7% 35%	4212
	11th to 20th	Day	16% 7% 3 8% 5% 5% 5% 4 7% 8% 34%	4211
	21st to end	Day	11% 6% 2 7% 5% 4 4 3 6% 8% 45%	4541
June	1st to 10th	Day	10% 6% 2 7% 6% 5% 5% 5% 6% 9% 40%	2655
	11th to 20th	Day	10% 6% 2 6% 6% 5% 6% 4 6% 9% 40%	2660
	21st to end	Day	10% 6% 3 6% 5% 5% 5% 5% 9% 9% 37%	2660
July	1st to 10th	Day	10% 6% 2 7% 5% 5% 5% 5% 7% 9% 37%	4440
	11th to 20th	Day	7% 4 2 5% 4 5% 5% 4 7% 11% 46%	4440
	21st to end	Day	7% 6% 2 7% 5% 6% 5% 4 7% 9% 41%	4543
August	1st to 10th	Day	11% 5% 2 6% 4 5% 5% 5% 6% 8% 43%	4104
	11th to 20th	Day	10% 6% 2 7% 5% 6% 5% 5% 8% 9% 38%	4044
	21st to end	Day	8% 6% 3 6% 6% 6% 6% 5% 7% 9% 39%	4468
September	1st to 10th	Day	10% 7% 2 6% 4 5% 6% 4 6% 9% 39%	2153
	11th to 20th	Day	9% 5% 2 6% 4 4 5% 4 7% 9% 46%	2090
	21st to end	Day	15% 7% 2 7% 5% 4 5% 3 7% 7% 37%	2090
October	1st to 10th	Day	13% 6% 2 6% 6% 5% 4 5% 6% 7% 41%	2045
	11th to 20th	Day	18% 9% 3 7% 5% 5% 5% 3 5% 7% 33%	1900
	21st to end	Day	19% 10% 3 8% 4 5% 4 3 5% 6% 31%	1929
November	1st to 10th	Day	12% 10% 3 8% 5% 5% 4 4 5% 6% 39%	1762
	11th to 20th	Day	16% 13% 3 9% 6% 5% 5% 3 5% 6% 30%	1800
	21st to end	Day	18% 15% 5% 9% 5% 4 4 4 4 6% 27%	1733
December	1st to 10th	Day	13% 13% 6% 14% 7% 6% 6% 4 5% 6% 21%	2600
	11th to 20th	Day	19% 20% 7% 9% 6% 5% 4 3 5% 5% 18%	2765
	21st to end	Day	27% 20% 7% 12% 4 4 3 3 3 4 13%	3982
January	1st to 10th	Night	13% 15% 6% 12% 6% 5% 5% 3 5% 5% 25%	6348
	11th to 20th	Night	12% 15% 7% 14% 8% 6% 6% 4 6% 6% 15%	6360
	21st to end	Night	18% 15% 8% 11% 5% 5% 5% 3 4 5% 22%	6567
February	1st to 10th	Night	16% 15% 4 12% 8% 5% 5% 3 5% 5% 24%	2600
	11th to 20th	Night	14% 13% 5% 10% 6% 4 5% 4 5% 6% 27%	2383
	21st to end	Night	19% 11% 4 9% 6% 5% 4 4 5% 6% 28%	1980
March	1st to 10th	Night	15% 10% 4 8% 5% 4 4 3 5% 7% 35%	5282
	11th to 20th	Night	10% 7% 3 6% 4 4 5% 4 6% 8% 42%	4980
	21st to end	Night	17% 9% 3 8% 5% 4 4 3 4 5% 37%	5467
April	1st to 10th	Night	16% 11% 2 6% 6% 4 4 4 6% 6% 36%	2082
	11th to 20th	Night	17% 8% 3 5% 5% 4 3 4 6% 7% 37%	1821
	21st to end	Night	16% 9% 3 6% 4 4 5% 4 5% 6% 39%	1800
May	1st to 10th	Night	17% 9% 4 7% 4 4 4 3 5% 8% 35%	2903
	11th to 20th	Night	15% 7% 3 6% 4 5% 4 3 4 8% 40%	2902
	21st to end	Night	10% 6% 2 5% 4 4 4 3 5% 8% 48%	3130
June	1st to 10th	Night	11% 5% 2 6% 3 4 5% 3 6% 9% 47%	1520
	11th to 20th	Night	9% 6% 2 6% 4 5% 4 4 7% 9% 44%	1520
	21st to end	Night	9% 6% 2 4 4 3 4 4 6% 9% 48%	1520
July	1st to 10th	Night	8% 3 2 5% 5% 4 6% 5% 7% 10% 46%	2530
	11th to 20th	Night	8% 4 1 4 4 3 4 3 6% 8% 54%	2530
	21st to end	Night	5% 4 2 6% 5% 6% 4 5% 6% 10% 47%	2996
August	1st to 10th	Night	11% 6% 2 6% 4 4 5% 3 5% 9% 47%	2825
	11th to 20th	Night	8% 5% 2 6% 4 4 5% 4 5% 7% 49%	2785
	21st to end	Night	8% 5% 2 7% 4 5% 4 4 5% 8% 48%	3183
September	1st to 10th	Night	10% 6% 2 6% 4 4 4 3 5% 7% 49%	2007
	11th to 20th	Night	9% 5% 2 4 2 3 4 3 5% 7% 55%	2090
	21st to end	Night	14% 7% 2 6% 4 4 4 3 5% 7% 43%	2090
October	1st to 10th	Night	13% 7% 3 6% 3 3 3 3 4 6% 47%	2134
	11th to 20th	Night	18% 9% 3 6% 5% 4 5% 4 5% 5% 37%	2280
	21st to end	Night	21% 8% 3 7% 4 5% 4 4 5% 6% 33%	2666
November	1st to 10th	Night	13% 8% 2 6% 5% 4 4 3 5% 7% 43%	2536
	11th to 20th	Night	16% 11% 4 7% 5% 5% 5% 4 6% 6% 31%	2600
	21st to end	Night	19% 13% 5% 8% 5% 4 4 3 6% 5% 28%	2662
December	1st to 10th	Night	12% 13% 4 13% 7% 6% 5% 4 6% 7% 23%	4580
	11th to 20th	Night	16% 19% 6% 13% 6% 4 4 3 4 5% 19%	5401
	21st to end	Night	26% 22% 7% 9% 5% 3 3 3 4 4 14%	6996

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	63% 6% 11% 14% 6% 1	3618
	11th to 20th	Day	74% 5% 9% 7% 4	3620
	21st to end	Day	72% 4 10% 9% 4	4377
February	1st to 10th	Day	63% 7% 9% 14% 7%	1800
	11th to 20th	Day	62% 5% 10% 15% 7% 1	1911
	21st to end	Day	58% 6% 12% 15% 7% 2	1650
March	1st to 10th	Day	56% 5% 12% 16% 9% 1	4569
	11th to 20th	Day	46% 6% 16% 22% 8% 1	4980
	21st to end	Day	56% 6% 10% 15% 11% 1	5465
April	1st to 10th	Day	52% 7% 11% 18% 11% 1	2335
	11th to 20th	Day	48% 6% 12% 20% 12% 2	2527
	21st to end	Day	48% 6% 13% 18% 13% 1	2600
May	1st to 10th	Day	46% 8% 12% 22% 11% 2	4250
	11th to 20th	Day	45% 9% 14% 22% 9% 1	4215
	21st to end	Day	36% 7% 12% 19% 22% 5%	4554
June	1st to 10th	Day	38% 8% 12% 26% 13% 3	2655
	11th to 20th	Day	39% 7% 14% 22% 16% 2	2660
	21st to end	Day	38% 9% 14% 21% 16% 2	2660
July	1st to 10th	Day	41% 6% 15% 20% 16% 2	4371
	11th to 20th	Day	30% 6% 13% 32% 17% 1	4365
	21st to end	Day	37% 7% 15% 19% 21% 2	4399
August	1st to 10th	Day	37% 7% 13% 26% 15% 1	4091
	11th to 20th	Day	40% 8% 11% 30% 11% 1	4083
	21st to end	Day	38% 7% 14% 27% 13% 1	4467
September	1st to 10th	Day	39% 8% 15% 22% 14% 2	2153
	11th to 20th	Day	32% 7% 13% 32% 15% 1	2090
	21st to end	Day	43% 7% 13% 23% 13%	2090
October	1st to 10th	Day	31% 5% 12% 31% 20% 1	3396
	11th to 20th	Day	39% 5% 12% 25% 18%	3140
	21st to end	Day	45% 5% 14% 23% 12% 1	3153
November	1st to 10th	Day	45% 7% 12% 23% 13% 1	1762
	11th to 20th	Day	54% 5% 13% 18% 8% 1	1800
	21st to end	Day	57% 7% 11% 17% 7%	1733
December	1st to 10th	Day	62% 6% 15% 12% 4	2600
	11th to 20th	Day	68% 5% 9% 12% 4	2761
	21st to end	Day	76% 4 7% 8% 5%	3982
January	1st to 10th	Night	58% 6% 10% 19% 6% 1	6348
	11th to 20th	Night	66% 6% 11% 10% 6%	6360
	21st to end	Night	65% 4 11% 12% 8%	6567
February	1st to 10th	Night	61% 7% 10% 14% 7% 1	2600
	11th to 20th	Night	57% 5% 12% 17% 9% 1	2384
	21st to end	Night	55% 5% 14% 17% 8% 1	1980
March	1st to 10th	Night	48% 5% 14% 22% 10% 1	5282
	11th to 20th	Night	38% 6% 15% 26% 15% 1	4980
	21st to end	Night	49% 5% 11% 20% 14% 1	5467
April	1st to 10th	Night	47% 6% 11% 20% 13% 2	2082
	11th to 20th	Night	43% 8% 11% 18% 18% 1	1821
	21st to end	Night	45% 7% 12% 18% 16% 3	1800
May	1st to 10th	Night	47% 7% 11% 20% 13% 3	2930
	11th to 20th	Night	41% 7% 11% 26% 12% 2	2903
	21st to end	Night	32% 7% 13% 21% 21% 5%	3138
June	1st to 10th	Night	34% 6% 12% 28% 18% 3	1520
	11th to 20th	Night	36% 9% 12% 25% 17% 2	1520
	21st to end	Night	33% 7% 14% 26% 20% 1	1520
July	1st to 10th	Night	31% 6% 13% 30% 14% 6%	2490
	11th to 20th	Night	27% 5% 14% 31% 21% 1	2482
	21st to end	Night	31% 7% 19% 19% 22% 2	2900
August	1st to 10th	Night	35% 6% 13% 27% 17% 1	2814
	11th to 20th	Night	33% 7% 11% 36% 11% 2	2812
	21st to end	Night	34% 6% 13% 31% 15% 1	3183
September	1st to 10th	Night	33% 8% 13% 27% 17% 2	2007
	11th to 20th	Night	28% 6% 11% 31% 22% 2	2090
	21st to end	Night	40% 7% 12% 27% 14% 1	2090
October	1st to 10th	Night	26% 4 9% 33% 28% 1	3563
	11th to 20th	Night	42% 4 12% 24% 18%	3779
	21st to end	Night	39% 5% 11% 31% 13% 1	4392
November	1st to 10th	Night	41% 6% 12% 26% 15% 1	2536
	11th to 20th	Night	51% 7% 14% 19% 9% 1	2600
	21st to end	Night	57% 7% 12% 18% 7%	2662
December	1st to 10th	Night	59% 6% 17% 15% 4	4580
	11th to 20th	Night	66% 5% 11% 13% 5% 1	5404
	21st to end	Night	74% 5% 9% 7% 6%	6996

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	22% 21% 36% 15% 4 1	300
	11th to 20th	Day	23% 18% 45% 12% 1 1	300
	21st to end	Day	26% 19% 34% 15% 4 1	330
February	1st to 10th	Day	25% 22% 37% 13% 2 1	300
	11th to 20th	Day	24% 22% 39% 14% 1	300
	21st to end	Day	25% 29% 34% 11% 1	249
March	1st to 10th	Day	26% 23% 34% 14% 3	337
	11th to 20th	Day	25% 14% 34% 21% 6% 1	500
	21st to end	Day	25% 17% 33% 19% 5% 1	550
April	1st to 10th	Day	22% 18% 33% 19% 7% 1	500
	11th to 20th	Day	26% 18% 31% 14% 7% 4	492
	21st to end	Day	25% 15% 30% 18% 10% 2	500
May	1st to 10th	Day	24% 15% 27% 21% 10% 3	503
	11th to 20th	Day	21% 10% 29% 23% 12% 6%	527
	21st to end	Day	14% 10% 23% 28% 17% 8%	549
June	1st to 10th	Day	12% 8% 30% 31% 14% 4	675
	11th to 20th	Day	13% 8% 31% 29% 15% 4	680
	21st to end	Day	12% 10% 30% 29% 14% 5%	680
July	1st to 10th	Day	9% 5% 25% 28% 23% 10%	671
	11th to 20th	Day	10% 8% 28% 28% 19% 7%	668
	21st to end	Day	9% 4 26% 28% 23% 9%	583
August	1st to 10th	Day	8% 5% 23% 27% 25% 13%	486
	11th to 20th	Day	12% 5% 21% 29% 21% 11%	479
	21st to end	Day	10% 5% 21% 28% 24% 12%	539
September	1st to 10th	Day	13% 6% 23% 24% 24% 9%	490
	11th to 20th	Day	10% 5% 17% 27% 27% 14%	490
	21st to end	Day	17% 11% 24% 21% 18% 8%	490
October	1st to 10th	Day	17% 11% 26% 22% 17% 7%	490
	11th to 20th	Day	21% 16% 28% 24% 9% 1	490
	21st to end	Day	27% 16% 34% 17% 6%	378
November	1st to 10th	Day	14% 22% 35% 20% 8% 1	300
	11th to 20th	Day	24% 22% 31% 17% 5% 1	300
	21st to end	Day	28% 19% 35% 12% 5%	265
December	1st to 10th	Day	20% 22% 37% 14% 7% 1	200
	11th to 20th	Day	29% 20% 36% 11% 3	207
	21st to end	Day	29% 24% 32% 13% 2	330
January	1st to 10th	Night	22% 15% 36% 21% 5% 1	1000
	11th to 20th	Night	26% 15% 33% 22% 4 1	1000
	21st to end	Night	20% 15% 34% 26% 5%	918
February	1st to 10th	Night	24% 14% 36% 24% 3	800
	11th to 20th	Night	24% 15% 33% 25% 3	783
	21st to end	Night	26% 14% 38% 20% 2	660
March	1st to 10th	Night	21% 13% 33% 26% 6%	800
	11th to 20th	Night	17% 18% 35% 24% 5% 1	800
	21st to end	Night	23% 12% 30% 26% 7% 1	880
April	1st to 10th	Night	20% 16% 34% 26% 4 1	682
	11th to 20th	Night	21% 11% 34% 26% 7% 1	593
	21st to end	Night	21% 10% 31% 32% 7%	600
May	1st to 10th	Night	19% 10% 31% 31% 8% 1	600
	11th to 20th	Night	22% 7% 26% 31% 13% 1	591
	21st to end	Night	12% 5% 25% 38% 19% 2	634
June	1st to 10th	Night	12% 4 24% 46% 13% 1	570
	11th to 20th	Night	11% 5% 23% 44% 17%	570
	21st to end	Night	11% 4 24% 42% 19% 1	570
July	1st to 10th	Night	8% 2 19% 40% 27% 4	555
	11th to 20th	Night	9% 4 19% 39% 24% 4	552
	21st to end	Night	5% 2 20% 48% 23% 3	624
August	1st to 10th	Night	8% 3 17% 41% 27% 3	567
	11th to 20th	Night	10% 3 19% 36% 30% 3	564
	21st to end	Night	10% 3 17% 35% 32% 3	627
September	1st to 10th	Night	13% 5% 19% 34% 25% 4	677
	11th to 20th	Night	11% 4 17% 33% 31% 5%	760
	21st to end	Night	16% 7% 21% 31% 21% 4	760
October	1st to 10th	Night	16% 6% 27% 30% 18% 3	760
	11th to 20th	Night	21% 14% 29% 26% 9% 2	760
	21st to end	Night	24% 12% 33% 26% 5%	836
November	1st to 10th	Night	18% 12% 31% 27% 11% 1	780
	11th to 20th	Night	23% 16% 33% 22% 6% 1	800
	21st to end	Night	26% 15% 33% 20% 6% 1	800
December	1st to 10th	Night	24% 16% 35% 20% 6%	800
	11th to 20th	Night	25% 15% 36% 20% 3	917
	21st to end	Night	32% 12% 35% 19% 2	1100

Page generated at 2025-05-23 09:20:57. Version ac07

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