Indian Foothills Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Indian Foothills Park clear sky chart from 2005-11-06 to 2026-09-29.

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	11% 7% 3 7% 4 4 4 3 5% 7% 44%	149222
	Night	11% 7% 3 6% 4 4 4 3 5% 7% 46%	142534
Transparency	Day	38% 5% 13% 26% 16% 2	152828
	Night	37% 5% 12% 25% 18% 3	147008
Seeing	Day	14% 10% 27% 27% 17% 5%	18325
	Night	14% 9% 31% 32% 13% 1	28036

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	13% 12% 4 10% 4 4 4 4 4 5% 36%	5069
	11th to 20th	Day	6% 8% 3 9% 6% 7% 6% 3 5% 6% 41%	5310
	21st to end	Day	14% 13% 4 9% 5% 3 3 3 3 4 38%	5812
February	1st to 10th	Day	16% 10% 4 8% 6% 4 4 3 5% 6% 35%	1890
	11th to 20th	Day	14% 10% 3 8% 5% 3 3 3 4 6% 40%	1844
	21st to end	Day	12% 10% 4 6% 4 3 4 4 5% 5% 42%	1757
March	1st to 10th	Day	15% 10% 4 4 3 2 2 2 3 4 50%	5046
	11th to 20th	Day	10% 6% 2 5% 3 3 3 3 5% 6% 52%	5090
	21st to end	Day	14% 12% 3 7% 5% 5% 5% 3 5% 8% 32%	5583
April	1st to 10th	Day	16% 7% 3 7% 4 4 3 3 5% 6% 42%	2509
	11th to 20th	Day	15% 10% 3 6% 4 3 3 3 5% 6% 41%	2494
	21st to end	Day	20% 7% 3 7% 5% 4 5% 3 6% 7% 33%	2541
May	1st to 10th	Day	14% 7% 3 6% 4 4 5% 4 6% 8% 39%	7617
	11th to 20th	Day	13% 6% 2 6% 4 4 4 3 6% 8% 43%	7746
	21st to end	Day	18% 8% 3 7% 4 4 5% 3 5% 6% 37%	9047
June	1st to 10th	Day	8% 5% 2 5% 4 4 4 5% 7% 10% 46%	2940
	11th to 20th	Day	9% 5% 2 6% 4 4 5% 4 6% 9% 46%	2940
	21st to end	Day	8% 5% 2 6% 4 4 4 4 7% 8% 48%	2940
July	1st to 10th	Day	8% 5% 2 6% 4 4 5% 4 6% 9% 47%	8280
	11th to 20th	Day	6% 5% 2 5% 4 4 5% 4 6% 9% 49%	7724
	21st to end	Day	9% 5% 2 6% 4 5% 5% 4 7% 11% 41%	8337
August	1st to 10th	Day	6% 4 2 5% 4 4 5% 4 6% 10% 48%	6014
	11th to 20th	Day	9% 6% 3 7% 4 4 5% 4 6% 9% 44%	5883
	21st to end	Day	4 4 2 5% 3 4 4 4 6% 11% 54%	6080
September	1st to 10th	Day	10% 4 2 5% 4 3 3 3 5% 7% 54%	2520
	11th to 20th	Day	10% 5% 2 5% 4 4 3 3 6% 8% 51%	2472
	21st to end	Day	9% 6% 2 5% 4 3 4 3 4 6% 52%	2196
October	1st to 10th	Day	12% 4 2 5% 4 3 4 3 4 5% 54%	2000
	11th to 20th	Day	14% 7% 2 5% 3 2 3 3 4 4 53%	2000
	21st to end	Day	17% 8% 3 6% 3 3 3 3 4 5% 46%	2200
November	1st to 10th	Day	12% 6% 2 5% 3 3 3 3 4 6% 53%	2026
	11th to 20th	Day	14% 7% 2 6% 4 3 3 2 6% 6% 48%	1787
	21st to end	Day	17% 10% 3 8% 3 3 3 2 4 5% 42%	1680
December	1st to 10th	Day	6% 8% 3 7% 3 4 3 3 4 7% 52%	2690
	11th to 20th	Day	11% 8% 4 9% 4 4 4 3 4 5% 46%	3088
	21st to end	Day	17% 20% 7% 11% 4 4 3 2 4 4 22%	4070
January	1st to 10th	Night	12% 11% 4 13% 5% 4 3 2 4 4 37%	7838
	11th to 20th	Night	9% 7% 3 9% 5% 5% 4 4 5% 5% 44%	7680
	21st to end	Night	13% 12% 4 8% 4 4 4 3 4 5% 38%	8402
February	1st to 10th	Night	14% 10% 4 7% 5% 5% 4 3 5% 6% 37%	2730
	11th to 20th	Night	14% 10% 3 7% 5% 4 4 3 4 6% 40%	2663
	21st to end	Night	13% 8% 3 7% 4 3 4 3 5% 5% 45%	2064
March	1st to 10th	Night	17% 10% 3 6% 3 2 3 2 4 4 46%	5029
	11th to 20th	Night	10% 6% 2 5% 3 3 3 3 4 6% 54%	5090
	21st to end	Night	14% 10% 4 7% 5% 5% 5% 4 5% 7% 35%	5588
April	1st to 10th	Night	12% 7% 3 5% 4 3 3 3 5% 7% 47%	2111
	11th to 20th	Night	14% 6% 2 7% 4 4 4 3 5% 6% 46%	2075
	21st to end	Night	16% 8% 3 8% 4 3 4 3 5% 7% 40%	2074
May	1st to 10th	Night	14% 7% 2 7% 4 4 4 3 5% 8% 40%	5266
	11th to 20th	Night	11% 6% 2 5% 4 3 4 4 6% 9% 46%	5128
	21st to end	Night	15% 7% 2 8% 4 4 4 3 5% 7% 40%	5139
June	1st to 10th	Night	7% 3 2 4 4 3 5% 4 6% 9% 53%	1680
	11th to 20th	Night	6% 4 2 5% 5% 3 5% 3 7% 10% 50%	1680
	21st to end	Night	4 4 1 4 4 4 4 3 7% 8% 56%	1680
July	1st to 10th	Night	8% 5% 2 5% 3 3 4 4 7% 10% 50%	4708
	11th to 20th	Night	5% 4 2 6% 4 4 4 4 6% 8% 53%	5244
	21st to end	Night	6% 4 2 5% 4 4 4 5% 8% 11% 45%	5770
August	1st to 10th	Night	6% 2 1 3 3 3 4 3 6% 10% 58%	4156
	11th to 20th	Night	9% 6% 2 5% 4 4 4 3 5% 8% 50%	4180
	21st to end	Night	4 3 1 4 3 4 4 3 6% 8% 60%	5046
September	1st to 10th	Night	10% 4 2 4 3 3 3 3 4 6% 58%	2100
	11th to 20th	Night	9% 4 1 6% 3 4 4 4 6% 7% 52%	2144
	21st to end	Night	8% 5% 2 5% 3 4 3 3 4 7% 55%	2360
October	1st to 10th	Night	9% 4 1 4 3 3 3 2 5% 6% 59%	2400
	11th to 20th	Night	13% 5% 2 5% 3 3 3 2 4 5% 55%	2400
	21st to end	Night	17% 8% 2 4 3 3 3 2 4 4 49%	2640
November	1st to 10th	Night	11% 5% 1 4 3 2 3 3 4 7% 57%	2490
	11th to 20th	Night	11% 7% 2 5% 3 3 4 3 4 6% 52%	2830
	21st to end	Night	18% 8% 2 5% 4 4 3 3 3 4 46%	2940
December	1st to 10th	Night	8% 7% 3 6% 4 3 4 3 4 7% 51%	4720
	11th to 20th	Night	14% 9% 3 6% 4 3 4 3 5% 6% 43%	5339
	21st to end	Night	21% 16% 5% 9% 4 4 3 3 3 5% 26%	7150

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	50% 4 11% 23% 11% 2	5070
	11th to 20th	Day	44% 4 11% 24% 14% 4	5310
	21st to end	Day	51% 3 12% 17% 15% 2	5812
February	1st to 10th	Day	50% 4 12% 22% 10% 1	1890
	11th to 20th	Day	47% 4 10% 21% 14% 3	1853
	21st to end	Day	43% 5% 10% 23% 16% 3	1757
March	1st to 10th	Day	40% 3 7% 25% 23% 3	5046
	11th to 20th	Day	32% 5% 10% 24% 25% 6%	5090
	21st to end	Day	49% 7% 16% 23% 5%	5585
April	1st to 10th	Day	43% 5% 11% 25% 15% 1	2509
	11th to 20th	Day	44% 5% 12% 23% 14% 2	2494
	21st to end	Day	50% 6% 12% 21% 10% 1	2541
May	1st to 10th	Day	41% 8% 13% 26% 12%	7655
	11th to 20th	Day	39% 7% 13% 24% 15% 2	7750
	21st to end	Day	46% 6% 9% 25% 13%	9061
June	1st to 10th	Day	31% 8% 16% 29% 14% 1	2940
	11th to 20th	Day	33% 8% 15% 26% 16% 2	2940
	21st to end	Day	31% 7% 17% 28% 14% 4	2940
July	1st to 10th	Day	34% 6% 14% 27% 18% 2	8211
	11th to 20th	Day	30% 7% 17% 27% 15% 4	7654
	21st to end	Day	35% 7% 20% 30% 7%	8155
August	1st to 10th	Day	29% 7% 15% 30% 18% 1	6000
	11th to 20th	Day	37% 6% 15% 31% 11% 1	5922
	21st to end	Day	24% 6% 15% 37% 15% 3	6079
September	1st to 10th	Day	30% 5% 13% 26% 20% 6%	2520
	11th to 20th	Day	31% 5% 11% 28% 22% 3	2472
	21st to end	Day	33% 5% 10% 26% 23% 3	2196
October	1st to 10th	Day	20% 2 6% 20% 39% 12%	3260
	11th to 20th	Day	22% 2 5% 22% 39% 9%	3240
	21st to end	Day	37% 3 8% 24% 25% 2	3538
November	1st to 10th	Day	33% 4 13% 25% 20% 4	2026
	11th to 20th	Day	37% 4 10% 26% 20% 3	1787
	21st to end	Day	45% 3 10% 28% 15%	1680
December	1st to 10th	Day	33% 5% 15% 31% 16% 1	2690
	11th to 20th	Day	42% 4 14% 28% 11% 1	3085
	21st to end	Day	66% 4 12% 12% 6% 1	4070
January	1st to 10th	Night	52% 4 12% 23% 9%	7839
	11th to 20th	Night	42% 4 9% 25% 16% 4	7680
	21st to end	Night	49% 4 12% 17% 15% 3	8402
February	1st to 10th	Night	47% 5% 12% 21% 13% 3	2730
	11th to 20th	Night	45% 4 11% 21% 17% 2	2664
	21st to end	Night	40% 5% 10% 22% 20% 4	2064
March	1st to 10th	Night	43% 4 7% 21% 22% 4	5029
	11th to 20th	Night	31% 4 7% 25% 27% 6%	5090
	21st to end	Night	47% 6% 13% 24% 8% 2	5588
April	1st to 10th	Night	36% 6% 9% 26% 19% 4	2111
	11th to 20th	Night	38% 5% 10% 26% 17% 5%	2075
	21st to end	Night	43% 5% 10% 23% 16% 1	2074
May	1st to 10th	Night	41% 7% 12% 24% 14% 1	5293
	11th to 20th	Night	34% 7% 12% 24% 18% 5%	5129
	21st to end	Night	43% 8% 10% 20% 19% 1	5149
June	1st to 10th	Night	25% 8% 16% 31% 17% 3	1680
	11th to 20th	Night	27% 8% 12% 28% 21% 4	1680
	21st to end	Night	24% 6% 16% 30% 19% 5%	1680
July	1st to 10th	Night	29% 6% 15% 28% 22% 2	4670
	11th to 20th	Night	28% 7% 15% 28% 18% 4	5195
	21st to end	Night	30% 7% 20% 36% 8% 1	5641
August	1st to 10th	Night	21% 6% 19% 29% 24% 1	4146
	11th to 20th	Night	31% 6% 14% 31% 17% 1	4207
	21st to end	Night	22% 5% 14% 39% 17% 3	5046
September	1st to 10th	Night	28% 4 11% 23% 27% 7%	2100
	11th to 20th	Night	30% 6% 10% 28% 22% 5%	2144
	21st to end	Night	30% 4 10% 25% 27% 4	2360
October	1st to 10th	Night	16% 3 6% 21% 45% 9%	3920
	11th to 20th	Night	23% 3 6% 23% 30% 14%	3899
	21st to end	Night	34% 4 7% 27% 25% 2	4252
November	1st to 10th	Night	30% 5% 12% 27% 22% 5%	2490
	11th to 20th	Night	34% 4 9% 26% 23% 4	2830
	21st to end	Night	43% 3 9% 26% 16% 2	2940
December	1st to 10th	Night	34% 4 13% 34% 14% 1	4720
	11th to 20th	Night	42% 3 13% 26% 15% 1	5341
	21st to end	Night	62% 4 12% 15% 6% 1	7150

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	19% 14% 40% 22% 5%	330
	11th to 20th	Day	26% 19% 38% 15% 2	330
	21st to end	Day	15% 16% 44% 20% 4	363
February	1st to 10th	Day	21% 15% 44% 16% 3	330
	11th to 20th	Day	20% 21% 38% 15% 6%	330
	21st to end	Day	16% 22% 41% 17% 3	273
March	1st to 10th	Day	18% 16% 48% 16% 2	330
	11th to 20th	Day	26% 14% 32% 23% 5%	330
	21st to end	Day	28% 21% 33% 14% 4	363
April	1st to 10th	Day	21% 17% 33% 22% 6% 1	529
	11th to 20th	Day	20% 18% 35% 21% 5% 1	532
	21st to end	Day	22% 13% 34% 23% 8% 1	561
May	1st to 10th	Day	17% 14% 33% 27% 9% 1	753
	11th to 20th	Day	18% 10% 28% 28% 14% 3	775
	21st to end	Day	16% 8% 27% 29% 16% 4	844
June	1st to 10th	Day	9% 5% 19% 33% 25% 9%	780
	11th to 20th	Day	11% 3 23% 35% 23% 5%	780
	21st to end	Day	7% 5% 30% 37% 18% 3	780
July	1st to 10th	Day	9% 4 15% 26% 33% 13%	771
	11th to 20th	Day	6% 2 18% 33% 31% 9%	768
	21st to end	Day	8% 3 16% 32% 31% 10%	849
August	1st to 10th	Day	7% 2 17% 39% 29% 7%	776
	11th to 20th	Day	8% 3 17% 35% 28% 8%	739
	21st to end	Day	8% 2 13% 31% 35% 11%	627
September	1st to 10th	Day	10% 3 14% 35% 29% 9%	570
	11th to 20th	Day	8% 2 15% 33% 31% 10%	522
	21st to end	Day	10% 7% 23% 30% 20% 9%	354
October	1st to 10th	Day	14% 6% 28% 28% 17% 8%	330
	11th to 20th	Day	12% 17% 37% 22% 12% 1	330
	21st to end	Day	28% 15% 33% 19% 5%	363
November	1st to 10th	Day	15% 11% 38% 24% 9% 3	330
	11th to 20th	Day	16% 15% 34% 23% 10% 2	330
	21st to end	Day	24% 17% 28% 25% 7%	330
December	1st to 10th	Day	12% 17% 37% 25% 7% 2	330
	11th to 20th	Day	15% 18% 38% 22% 6% 1	330
	21st to end	Day	21% 21% 38% 18% 2	363
January	1st to 10th	Night	16% 12% 41% 24% 7%	1050
	11th to 20th	Night	16% 16% 41% 22% 5%	1050
	21st to end	Night	15% 14% 40% 27% 3	1155
February	1st to 10th	Night	18% 12% 41% 26% 3	1050
	11th to 20th	Night	18% 14% 38% 27% 3	1029
	21st to end	Night	18% 14% 43% 21% 3	680
March	1st to 10th	Night	19% 14% 39% 26% 3	630
	11th to 20th	Night	20% 10% 37% 28% 5%	630
	21st to end	Night	25% 12% 37% 23% 4	693
April	1st to 10th	Night	15% 13% 37% 30% 4	630
	11th to 20th	Night	17% 13% 33% 29% 7%	623
	21st to end	Night	19% 9% 37% 28% 7%	630
May	1st to 10th	Night	15% 7% 34% 35% 8% 1	630
	11th to 20th	Night	16% 5% 28% 35% 15% 1	621
	21st to end	Night	13% 5% 27% 34% 19% 1	683
June	1st to 10th	Night	7% 3 19% 47% 22% 3	630
	11th to 20th	Night	6% 2 23% 45% 21% 2	630
	21st to end	Night	4 4 27% 44% 20% 1	630
July	1st to 10th	Night	9% 3 10% 41% 33% 4	615
	11th to 20th	Night	5% 1 13% 43% 34% 3	612
	21st to end	Night	6% 2 11% 45% 34% 2	690
August	1st to 10th	Night	5% 3 14% 46% 30% 2	627
	11th to 20th	Night	6% 3 13% 41% 34% 3	624
	21st to end	Night	6% 1 10% 42% 39% 3	693
September	1st to 10th	Night	11% 3 15% 39% 28% 4	630
	11th to 20th	Night	11% 2 17% 38% 28% 5%	630
	21st to end	Night	9% 5% 21% 37% 24% 3	696
October	1st to 10th	Night	11% 5% 26% 35% 22% 3	800
	11th to 20th	Night	16% 9% 34% 33% 9%	800
	21st to end	Night	20% 12% 33% 27% 8%	880
November	1st to 10th	Night	13% 8% 34% 35% 10%	820
	11th to 20th	Night	14% 12% 37% 29% 7%	940
	21st to end	Night	21% 10% 36% 28% 5%	1050
December	1st to 10th	Night	17% 11% 39% 27% 6%	1050
	11th to 20th	Night	20% 11% 35% 30% 5%	1050
	21st to end	Night	21% 14% 37% 25% 3	1155

Page generated at 2026-09-26 03:18:45. Version ac07

Copyright © 2026 Attilla Danko.