Honea-Egypt Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Honea-Egypt Observatory clear sky chart from 2005-11-06 to 2024-11-10.

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% 6% 2 6% 5% 4 5% 4 6% 8% 41%	101100
	Night	14% 6% 2 5% 4 3 3 3 5% 7% 46%	98116
Transparency	Day	40% 6% 11% 19% 17% 7%	104801
	Night	36% 5% 11% 20% 18% 9%	102542
Seeing	Day	15% 8% 21% 27% 21% 8%	14898
	Night	17% 8% 25% 32% 17% 2	24738

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	18% 10% 2 4 3 2 3 2 4 5% 45%	2847
	11th to 20th	Day	19% 6% 2 5% 3 2 2 2 3 5% 51%	2850
	21st to end	Day	24% 8% 2 6% 3 3 3 3 5% 8% 36%	3135
February	1st to 10th	Day	24% 8% 3 6% 4 3 3 3 4 6% 37%	1805
	11th to 20th	Day	21% 9% 3 6% 5% 3 3 2 3 6% 40%	1849
	21st to end	Day	20% 8% 3 6% 4 3 3 2 4 5% 41%	1723
March	1st to 10th	Day	19% 8% 3 8% 6% 5% 4 4 6% 6% 31%	3436
	11th to 20th	Day	21% 8% 2 7% 5% 5% 5% 4 6% 7% 30%	3480
	21st to end	Day	17% 8% 2 5% 5% 4 4 4 5% 5% 41%	3814
April	1st to 10th	Day	17% 8% 2 8% 5% 4 4 4 4 6% 38%	2090
	11th to 20th	Day	18% 7% 3 6% 5% 5% 4 3 5% 6% 38%	2204
	21st to end	Day	12% 7% 2 6% 5% 4 4 4 6% 7% 42%	2280
May	1st to 10th	Day	20% 8% 3 7% 6% 6% 5% 4 6% 7% 29%	3912
	11th to 20th	Day	14% 7% 2 6% 4 4 5% 3 6% 7% 42%	4082
	21st to end	Day	11% 7% 2 7% 5% 6% 6% 5% 8% 10% 33%	4477
June	1st to 10th	Day	7% 5% 2 6% 5% 6% 7% 5% 7% 9% 42%	2470
	11th to 20th	Day	6% 4 1 5% 4 5% 7% 5% 9% 11% 43%	2470
	21st to end	Day	7% 5% 2 8% 7% 7% 8% 6% 9% 9% 31%	2470
July	1st to 10th	Day	9% 4 2 6% 5% 5% 7% 6% 8% 12% 37%	4120
	11th to 20th	Day	6% 7% 3 7% 6% 7% 7% 5% 8% 11% 33%	4120
	21st to end	Day	14% 9% 3 9% 6% 5% 6% 5% 8% 9% 27%	4465
August	1st to 10th	Day	2 1 1 3 3 4 4 4 7% 10% 61%	4104
	11th to 20th	Day	3 2 1 4 4 5% 7% 5% 9% 13% 47%	3918
	21st to end	Day	6% 5% 2 8% 6% 6% 6% 5% 7% 9% 40%	4070
September	1st to 10th	Day	7% 6% 2 6% 6% 5% 5% 5% 7% 9% 41%	2090
	11th to 20th	Day	13% 7% 2 7% 6% 6% 5% 4 5% 7% 38%	2090
	21st to end	Day	8% 4 2 6% 4 5% 5% 4 6% 7% 48%	2090
October	1st to 10th	Day	7% 3 2 4 4 3 4 3 5% 6% 58%	1985
	11th to 20th	Day	10% 5% 2 6% 3 4 4 3 4 6% 52%	1900
	21st to end	Day	14% 5% 2 4 3 3 3 3 4 4 54%	2090
November	1st to 10th	Day	12% 6% 2 6% 4 3 4 4 6% 7% 46%	1948
	11th to 20th	Day	11% 7% 2 5% 4 3 3 4 6% 5% 49%	1900
	21st to end	Day	17% 7% 3 6% 5% 4 4 3 4 5% 43%	1810
December	1st to 10th	Day	15% 9% 2 6% 5% 4 4 3 4 6% 41%	1710
	11th to 20th	Day	15% 7% 3 7% 5% 4 4 3 4 6% 42%	2161
	21st to end	Day	18% 7% 2 6% 3 3 4 2 4 5% 46%	3135
January	1st to 10th	Night	18% 8% 2 5% 2 3 2 2 4 6% 47%	4108
	11th to 20th	Night	19% 6% 2 5% 3 2 2 2 3 4 53%	4120
	21st to end	Night	23% 10% 2 5% 3 2 3 3 4 7% 38%	4532
February	1st to 10th	Night	21% 9% 3 7% 4 3 3 3 4 5% 39%	2390
	11th to 20th	Night	22% 8% 2 5% 3 3 2 2 4 5% 43%	2218
	21st to end	Night	23% 7% 2 6% 4 3 3 2 5% 5% 40%	1728
March	1st to 10th	Night	24% 10% 3 6% 4 4 4 4 5% 5% 32%	3419
	11th to 20th	Night	24% 9% 3 7% 5% 4 3 3 5% 6% 31%	3480
	21st to end	Night	15% 8% 3 7% 4 4 4 3 4 5% 43%	3817
April	1st to 10th	Night	15% 8% 2 5% 5% 4 4 4 6% 6% 42%	2090
	11th to 20th	Night	17% 7% 2 5% 4 3 3 3 5% 8% 44%	1923
	21st to end	Night	16% 6% 3 5% 4 3 3 3 5% 7% 46%	1900
May	1st to 10th	Night	25% 8% 2 7% 5% 4 4 3 5% 7% 30%	2983
	11th to 20th	Night	15% 7% 2 6% 4 3 4 3 5% 6% 44%	2823
	21st to end	Night	13% 6% 2 6% 4 5% 4 4 8% 10% 37%	3090
June	1st to 10th	Night	6% 4 1 4 3 3 4 5% 7% 9% 54%	1710
	11th to 20th	Night	4 3 1 3 3 4 4 3 7% 11% 56%	1710
	21st to end	Night	5% 4 2 6% 5% 4 5% 6% 8% 11% 45%	1710
July	1st to 10th	Night	6% 4 1 5% 4 4 5% 5% 9% 13% 44%	2850
	11th to 20th	Night	4 4 2 6% 5% 5% 5% 5% 6% 12% 46%	2850
	21st to end	Night	10% 8% 3 8% 5% 4 5% 4 6% 9% 38%	3098
August	1st to 10th	Night	1 2 1 2 2 2 2 3 5% 10% 71%	2836
	11th to 20th	Night	2 2 1 2 2 4 4 3 8% 13% 59%	2914
	21st to end	Night	5% 3 1 5% 4 5% 5% 6% 8% 11% 47%	3566
September	1st to 10th	Night	6% 4 2 6% 4 4 4 4 7% 9% 49%	2090
	11th to 20th	Night	11% 5% 2 7% 5% 4 5% 4 5% 8% 44%	2090
	21st to end	Night	9% 4 1 4 3 3 4 3 5% 9% 55%	2090
October	1st to 10th	Night	5% 4 2 4 3 3 3 3 4 8% 61%	2175
	11th to 20th	Night	11% 5% 1 3 2 2 3 3 5% 6% 60%	2280
	21st to end	Night	12% 6% 2 4 3 2 3 2 3 4 59%	2508
November	1st to 10th	Night	12% 7% 2 4 3 4 3 2 5% 6% 52%	2335
	11th to 20th	Night	13% 6% 2 5% 4 4 3 3 5% 6% 50%	2280
	21st to end	Night	18% 6% 3 6% 3 3 3 3 5% 5% 44%	2365
December	1st to 10th	Night	19% 9% 2 5% 4 4 3 3 4 5% 43%	2470
	11th to 20th	Night	17% 9% 3 6% 4 3 3 3 4 6% 41%	3036
	21st to end	Night	17% 8% 2 5% 3 2 3 3 4 5% 47%	4532

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	43% 3 5% 16% 23% 10%	2848
	11th to 20th	Day	37% 4 4 19% 28% 8%	2850
	21st to end	Day	48% 2 4 18% 17% 11%	3135
February	1st to 10th	Day	50% 4 5% 13% 17% 11%	1805
	11th to 20th	Day	49% 3 7% 13% 17% 11%	1859
	21st to end	Day	48% 4 7% 15% 14% 11%	1723
March	1st to 10th	Day	53% 5% 9% 14% 16% 4	3436
	11th to 20th	Day	52% 6% 9% 13% 15% 5%	3480
	21st to end	Day	45% 4 7% 17% 22% 4	3814
April	1st to 10th	Day	49% 5% 5% 17% 15% 9%	2090
	11th to 20th	Day	46% 5% 8% 15% 17% 9%	2204
	21st to end	Day	40% 6% 8% 20% 20% 6%	2280
May	1st to 10th	Day	53% 7% 10% 15% 10% 4	3947
	11th to 20th	Day	41% 7% 9% 18% 23% 3	4086
	21st to end	Day	40% 10% 12% 28% 10% 1	4489
June	1st to 10th	Day	36% 8% 15% 24% 16% 1	2470
	11th to 20th	Day	34% 8% 16% 24% 15% 3	2470
	21st to end	Day	45% 9% 15% 20% 9%	2470
July	1st to 10th	Day	39% 6% 28% 24% 3	4056
	11th to 20th	Day	44% 7% 18% 22% 10%	4051
	21st to end	Day	51% 8% 18% 19% 4	4325
August	1st to 10th	Day	18% 6% 15% 37% 23%	4090
	11th to 20th	Day	28% 6% 31% 29% 6% 1	3957
	21st to end	Day	40% 9% 16% 20% 14% 2	4069
September	1st to 10th	Day	39% 9% 13% 18% 14% 6%	2090
	11th to 20th	Day	43% 8% 12% 18% 15% 4	2090
	21st to end	Day	34% 6% 11% 18% 18% 13%	2090
October	1st to 10th	Day	18% 3 5% 14% 20% 39%	3297
	11th to 20th	Day	24% 3 4 16% 34% 19%	3140
	21st to end	Day	29% 3 3 15% 36% 14%	3428
November	1st to 10th	Day	38% 5% 9% 17% 20% 11%	1948
	11th to 20th	Day	38% 4 9% 14% 23% 13%	1900
	21st to end	Day	44% 5% 6% 16% 17% 11%	1810
December	1st to 10th	Day	45% 5% 8% 17% 18% 7%	1710
	11th to 20th	Day	43% 4 7% 14% 22% 10%	2159
	21st to end	Day	42% 4 5% 14% 24% 11%	3135
January	1st to 10th	Night	40% 4 6% 19% 19% 12%	4108
	11th to 20th	Night	38% 3 5% 17% 27% 10%	4120
	21st to end	Night	48% 3 4 16% 19% 9%	4532
February	1st to 10th	Night	48% 4 5% 13% 16% 14%	2390
	11th to 20th	Night	44% 4 7% 15% 18% 12%	2218
	21st to end	Night	47% 4 6% 13% 15% 14%	1728
March	1st to 10th	Night	54% 5% 7% 14% 15% 5%	3419
	11th to 20th	Night	54% 6% 9% 14% 13% 5%	3480
	21st to end	Night	43% 5% 9% 14% 23% 7%	3817
April	1st to 10th	Night	43% 5% 10% 17% 16% 10%	2090
	11th to 20th	Night	40% 4 12% 16% 16% 12%	1923
	21st to end	Night	40% 5% 8% 20% 20% 7%	1900
May	1st to 10th	Night	54% 6% 9% 17% 10% 4	3013
	11th to 20th	Night	41% 6% 9% 19% 21% 4	2824
	21st to end	Night	40% 8% 15% 27% 8% 1	3099
June	1st to 10th	Night	24% 8% 17% 33% 18%	1710
	11th to 20th	Night	21% 8% 18% 30% 18% 4	1710
	21st to end	Night	31% 9% 19% 28% 12% 1	1710
July	1st to 10th	Night	31% 7% 32% 26% 4	2805
	11th to 20th	Night	32% 7% 24% 27% 10%	2796
	21st to end	Night	41% 10% 21% 24% 4	2999
August	1st to 10th	Night	12% 4 18% 43% 21% 1	2826
	11th to 20th	Night	16% 6% 35% 34% 8% 1	2941
	21st to end	Night	29% 12% 20% 27% 10% 2	3566
September	1st to 10th	Night	31% 8% 21% 21% 13% 6%	2090
	11th to 20th	Night	37% 8% 14% 20% 16% 6%	2090
	21st to end	Night	27% 5% 15% 22% 19% 12%	2090
October	1st to 10th	Night	17% 3 6% 18% 16% 40%	3630
	11th to 20th	Night	16% 3 4 22% 32% 22%	3779
	21st to end	Night	24% 2 4 17% 37% 16%	4120
November	1st to 10th	Night	34% 5% 10% 20% 21% 10%	2335
	11th to 20th	Night	36% 4 9% 18% 21% 12%	2280
	21st to end	Night	42% 4 7% 17% 19% 11%	2365
December	1st to 10th	Night	44% 4 8% 19% 15% 9%	2470
	11th to 20th	Night	46% 4 6% 10% 20% 14%	3037
	21st to end	Night	40% 4 6% 13% 28% 8%	4532

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	27% 16% 36% 16% 3 1	270
	11th to 20th	Day	31% 12% 32% 19% 4 1	270
	21st to end	Day	28% 17% 35% 16% 4	297
February	1st to 10th	Day	30% 20% 32% 14% 4 1	270
	11th to 20th	Day	33% 20% 28% 16% 2	270
	21st to end	Day	32% 24% 34% 8% 1	225
March	1st to 10th	Day	28% 18% 38% 11% 4	270
	11th to 20th	Day	21% 24% 35% 15% 4	270
	21st to end	Day	28% 12% 40% 16% 5%	297
April	1st to 10th	Day	21% 21% 38% 17% 3	270
	11th to 20th	Day	28% 16% 27% 20% 8%	402
	21st to end	Day	18% 14% 36% 23% 8% 1	460
May	1st to 10th	Day	19% 11% 37% 24% 8% 1	545
	11th to 20th	Day	15% 6% 32% 32% 12% 3	675
	21st to end	Day	12% 7% 30% 33% 14% 3	734
June	1st to 10th	Day	8% 3 17% 36% 28% 8%	680
	11th to 20th	Day	7% 2 18% 39% 27% 7%	680
	21st to end	Day	9% 2 12% 34% 30% 13%	680
July	1st to 10th	Day	8% 4 9% 30% 34% 15%	671
	11th to 20th	Day	4 3 4 32% 41% 16%	668
	21st to end	Day	6% 2 4 32% 43% 14%	739
August	1st to 10th	Day	3 2 3 27% 48% 17%	676
	11th to 20th	Day	5% 1 2 23% 48% 20%	594
	21st to end	Day	8% 3 7% 22% 35% 26%	481
September	1st to 10th	Day	9% 3 7% 27% 39% 16%	300
	11th to 20th	Day	11% 2 8% 32% 34% 13%	300
	21st to end	Day	10% 2 12% 36% 31% 10%	300
October	1st to 10th	Day	7% 2 21% 40% 26% 5%	300
	11th to 20th	Day	12% 6% 25% 33% 18% 6%	300
	21st to end	Day	22% 11% 25% 22% 16% 4	330
November	1st to 10th	Day	16% 8% 26% 32% 14% 2	297
	11th to 20th	Day	18% 8% 33% 31% 8% 2	270
	21st to end	Day	24% 21% 29% 20% 4 3	270
December	1st to 10th	Day	21% 9% 36% 21% 9% 4	270
	11th to 20th	Day	26% 18% 33% 19% 4	270
	21st to end	Day	24% 16% 35% 20% 5% 1	297
January	1st to 10th	Night	24% 14% 31% 24% 7%	950
	11th to 20th	Night	24% 15% 29% 26% 6%	950
	21st to end	Night	24% 13% 31% 27% 5%	1045
February	1st to 10th	Night	29% 14% 30% 24% 4	870
	11th to 20th	Night	29% 12% 31% 23% 4	744
	21st to end	Night	28% 17% 35% 18% 3	472
March	1st to 10th	Night	27% 11% 33% 24% 5%	570
	11th to 20th	Night	23% 10% 36% 26% 6%	570
	21st to end	Night	19% 12% 40% 23% 6%	627
April	1st to 10th	Night	19% 11% 40% 26% 5%	570
	11th to 20th	Night	23% 10% 32% 27% 7%	563
	21st to end	Night	19% 9% 39% 24% 9%	570
May	1st to 10th	Night	19% 8% 36% 30% 7% 1	570
	11th to 20th	Night	17% 5% 31% 34% 11% 2	561
	21st to end	Night	10% 4 31% 35% 19% 1	617
June	1st to 10th	Night	8% 2 16% 45% 26% 3	570
	11th to 20th	Night	4 3 20% 50% 21% 2	570
	21st to end	Night	6% 2 14% 41% 31% 6%	570
July	1st to 10th	Night	5% 3 8% 44% 33% 6%	555
	11th to 20th	Night	4 1 8% 49% 33% 6%	552
	21st to end	Night	5% 2 7% 47% 34% 5%	624
August	1st to 10th	Night	3 4 55% 34% 4	567
	11th to 20th	Night	5% 5% 48% 34% 8%	564
	21st to end	Night	6% 1 6% 37% 41% 9%	627
September	1st to 10th	Night	6% 2 8% 35% 40% 9%	570
	11th to 20th	Night	12% 3 9% 32% 39% 5%	570
	21st to end	Night	11% 2 13% 35% 33% 6%	570
October	1st to 10th	Night	6% 2 14% 42% 32% 4	655
	11th to 20th	Night	13% 3 25% 38% 20% 1	760
	21st to end	Night	16% 7% 28% 29% 18% 3	836
November	1st to 10th	Night	15% 5% 27% 35% 18% 2	779
	11th to 20th	Night	17% 10% 26% 33% 15%	760
	21st to end	Night	21% 10% 30% 26% 12% 2	845
December	1st to 10th	Night	23% 9% 27% 28% 11% 1	950
	11th to 20th	Night	26% 9% 30% 27% 6% 1	950
	21st to end	Night	25% 10% 30% 27% 9%	1045

Page generated at 2024-11-07 05:55:45. Version ac07

Copyright © 2024 Attilla Danko.