Lynch Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lynch Park 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	17% 7% 2 6% 4 4 4 4 5% 7% 39%	101266
	Night	18% 8% 2 6% 4 4 4 3 5% 6% 39%	97904
Transparency	Day	23% 48% 7% 13% 8% 1	104817
	Night	24% 48% 7% 12% 9% 1	102442
Seeing	Day	18% 6% 24% 33% 16% 3	15091
	Night	20% 8% 29% 30% 12% 1	23947

By Month

Percentage Cloud Cover NE (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	15% 8% 3 5% 4 3 3 3 4 6% 46%	2517
	11th to 20th	Day	17% 7% 3 8% 3 3 3 3 6% 5% 42%	2520
	21st to end	Day	20% 11% 3 6% 5% 4 4 3 4 5% 35%	2772
February	1st to 10th	Day	20% 8% 3 5% 4 4 4 5% 5% 7% 35%	1767
	11th to 20th	Day	14% 8% 2 6% 4 4 4 5% 6% 7% 40%	1848
	21st to end	Day	17% 9% 2 7% 5% 4 4 4 6% 6% 36%	1570
March	1st to 10th	Day	26% 12% 3 7% 4 3 4 3 4 5% 30%	3116
	11th to 20th	Day	14% 7% 3 6% 4 3 4 4 6% 7% 42%	3372
	21st to end	Day	25% 8% 2 5% 4 4 3 4 5% 5% 34%	3973
April	1st to 10th	Day	20% 8% 3 5% 5% 4 4 3 4 6% 38%	2280
	11th to 20th	Day	17% 6% 2 5% 5% 4 4 4 6% 7% 39%	2292
	21st to end	Day	20% 5% 2 5% 4 4 5% 4 5% 6% 38%	2470
May	1st to 10th	Day	22% 12% 4 8% 4 3 4 4 5% 8% 28%	4106
	11th to 20th	Day	21% 9% 3 8% 5% 4 4 3 5% 6% 33%	4103
	21st to end	Day	14% 6% 2 5% 4 3 4 3 6% 8% 45%	4837
June	1st to 10th	Day	19% 7% 2 5% 5% 5% 5% 3 7% 7% 36%	2660
	11th to 20th	Day	15% 6% 2 6% 4 4 4 5% 6% 9% 39%	2660
	21st to end	Day	16% 6% 2 6% 4 4 5% 5% 6% 9% 36%	2660
July	1st to 10th	Day	11% 7% 3 7% 5% 5% 5% 4 7% 10% 36%	4440
	11th to 20th	Day	9% 6% 2 6% 5% 4 5% 5% 7% 10% 40%	4440
	21st to end	Day	16% 7% 3 6% 4 4 4 4 6% 8% 37%	4814
August	1st to 10th	Day	15% 6% 3 6% 5% 5% 5% 4 7% 9% 35%	4110
	11th to 20th	Day	14% 8% 3 7% 4 4 4 4 6% 8% 39%	4045
	21st to end	Day	7% 4 2 5% 4 4 5% 5% 7% 10% 47%	4190
September	1st to 10th	Day	13% 6% 1 5% 3 3 4 5% 5% 7% 48%	2256
	11th to 20th	Day	14% 6% 2 4 4 3 2 3 4 6% 53%	2090
	21st to end	Day	16% 6% 2 6% 4 3 4 3 5% 7% 44%	2090
October	1st to 10th	Day	22% 6% 2 6% 3 4 3 3 4 5% 42%	2090
	11th to 20th	Day	15% 6% 2 5% 4 3 4 3 5% 7% 46%	1861
	21st to end	Day	20% 7% 2 5% 4 4 3 4 5% 6% 41%	1881
November	1st to 10th	Day	15% 6% 2 5% 3 4 3 3 4 5% 49%	1761
	11th to 20th	Day	18% 8% 2 4 3 3 3 3 4 6% 46%	1710
	21st to end	Day	18% 7% 2 5% 3 4 3 3 5% 6% 44%	1710
December	1st to 10th	Day	19% 8% 3 7% 4 3 4 3 4 5% 40%	1577
	11th to 20th	Day	22% 7% 2 5% 2 4 4 3 3 6% 43%	1906
	21st to end	Day	22% 10% 3 7% 4 4 3 3 5% 5% 34%	2772
January	1st to 10th	Night	19% 7% 2 4 3 3 3 3 4 6% 47%	4429
	11th to 20th	Night	15% 9% 3 8% 5% 4 4 3 4 6% 39%	4440
	21st to end	Night	21% 13% 4 8% 4 4 4 3 5% 5% 30%	4884
February	1st to 10th	Night	16% 10% 2 6% 5% 4 4 3 6% 6% 37%	2409
	11th to 20th	Night	15% 9% 3 6% 4 4 4 3 5% 6% 41%	2218
	21st to end	Night	19% 9% 2 5% 4 3 3 3 4 6% 43%	1884
March	1st to 10th	Night	30% 10% 2 5% 3 3 3 2 5% 5% 32%	3724
	11th to 20th	Night	12% 10% 3 8% 5% 5% 5% 4 6% 5% 38%	3586
	21st to end	Night	25% 8% 2 6% 4 4 4 4 5% 4 33%	3644
April	1st to 10th	Night	19% 9% 2 7% 5% 4 5% 3 5% 6% 35%	1900
	11th to 20th	Night	19% 8% 3 5% 5% 3 4 3 5% 5% 40%	1835
	21st to end	Night	20% 7% 3 7% 5% 5% 4 3 4 5% 37%	1710
May	1st to 10th	Night	23% 13% 3 8% 5% 4 4 3 5% 6% 27%	2834
	11th to 20th	Night	22% 10% 3 7% 5% 5% 6% 4 7% 7% 26%	2813
	21st to end	Night	17% 7% 3 6% 5% 3 3 3 5% 7% 41%	2742
June	1st to 10th	Night	19% 9% 2 7% 5% 4 3 3 4 6% 37%	1520
	11th to 20th	Night	18% 7% 2 6% 3 4 4 3 6% 10% 37%	1520
	21st to end	Night	17% 6% 2 7% 4 4 4 4 7% 8% 37%	1520
July	1st to 10th	Night	10% 7% 3 7% 5% 5% 6% 5% 7% 10% 35%	2520
	11th to 20th	Night	9% 6% 2 8% 6% 5% 5% 5% 8% 9% 38%	2520
	21st to end	Night	15% 9% 3 7% 5% 4 4 4 5% 7% 35%	2739
August	1st to 10th	Night	18% 7% 3 8% 5% 5% 5% 4 6% 8% 31%	2787
	11th to 20th	Night	10% 8% 3 7% 6% 6% 6% 5% 7% 8% 35%	2782
	21st to end	Night	8% 5% 2 4 4 4 4 3 5% 10% 51%	3463
September	1st to 10th	Night	13% 5% 2 6% 4 4 3 4 5% 7% 47%	1924
	11th to 20th	Night	14% 6% 1 5% 3 3 3 2 4 5% 54%	2090
	21st to end	Night	17% 6% 2 6% 3 4 4 3 5% 7% 43%	2090
October	1st to 10th	Night	20% 6% 2 6% 5% 4 3 3 4 5% 41%	2090
	11th to 20th	Night	15% 5% 2 5% 3 4 4 4 5% 7% 46%	2316
	21st to end	Night	22% 7% 2 6% 4 3 4 3 4 6% 40%	2717
November	1st to 10th	Night	14% 5% 2 5% 4 3 3 3 5% 6% 48%	2537
	11th to 20th	Night	17% 7% 2 5% 4 3 3 4 4 5% 46%	2477
	21st to end	Night	16% 7% 3 4 4 4 4 3 4 7% 44%	2470
December	1st to 10th	Night	19% 9% 2 6% 5% 4 3 4 4 5% 38%	2598
	11th to 20th	Night	19% 7% 2 5% 4 4 3 4 6% 6% 40%	3288
	21st to end	Night	21% 10% 3 6% 4 3 3 3 4 6% 37%	4884

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	24% 39% 7% 23% 6% 1	2518
	11th to 20th	Day	26% 39% 6% 19% 9% 1	2520
	21st to end	Day	36% 43% 6% 11% 4	2772
February	1st to 10th	Day	17% 66% 5% 7% 4 1	1767
	11th to 20th	Day	16% 65% 4 8% 7% 1	1857
	21st to end	Day	14% 66% 5% 8% 5% 1	1570
March	1st to 10th	Day	39% 41% 5% 7% 7% 1	3119
	11th to 20th	Day	19% 44% 12% 13% 9% 2	3372
	21st to end	Day	34% 42% 4 8% 8% 5%	3973
April	1st to 10th	Day	19% 65% 3 7% 5% 2	2280
	11th to 20th	Day	14% 66% 5% 8% 6% 1	2292
	21st to end	Day	17% 65% 3 8% 7%	2470
May	1st to 10th	Day	33% 47% 8% 8% 4	4120
	11th to 20th	Day	33% 43% 11% 9% 4	4107
	21st to end	Day	21% 43% 10% 14% 13%	4837
June	1st to 10th	Day	13% 66% 5% 9% 7%	2660
	11th to 20th	Day	13% 65% 5% 8% 8% 1	2660
	21st to end	Day	14% 65% 5% 8% 8%	2660
July	1st to 10th	Day	28% 38% 9% 13% 12% 1	4370
	11th to 20th	Day	24% 38% 12% 16% 10%	4365
	21st to end	Day	30% 37% 9% 14% 9% 1	4661
August	1st to 10th	Day	30% 40% 12% 15% 4	4096
	11th to 20th	Day	29% 39% 9% 19% 5%	4084
	21st to end	Day	16% 40% 10% 23% 12% 1	4190
September	1st to 10th	Day	12% 61% 6% 12% 9%	2256
	11th to 20th	Day	16% 60% 4 9% 10% 2	2090
	21st to end	Day	17% 60% 4 11% 8% 1	2090
October	1st to 10th	Day	25% 38% 6% 16% 13% 2	3480
	11th to 20th	Day	17% 37% 4 19% 20% 3	3064
	21st to end	Day	17% 37% 6% 23% 15% 1	3081
November	1st to 10th	Day	18% 57% 7% 11% 6% 1	1761
	11th to 20th	Day	17% 60% 5% 7% 10% 1	1710
	21st to end	Day	16% 60% 6% 10% 8% 1	1710
December	1st to 10th	Day	20% 60% 7% 6% 8%	1577
	11th to 20th	Day	23% 50% 6% 8% 9% 4	1906
	21st to end	Day	33% 40% 6% 14% 7% 1	2772
January	1st to 10th	Night	24% 38% 8% 21% 7% 2	4429
	11th to 20th	Night	28% 38% 7% 15% 9% 2	4440
	21st to end	Night	40% 42% 5% 8% 4 1	4884
February	1st to 10th	Night	17% 66% 5% 6% 5% 1	2409
	11th to 20th	Night	17% 64% 3 7% 8% 1	2220
	21st to end	Night	16% 64% 3 9% 6% 2	1884
March	1st to 10th	Night	38% 41% 5% 8% 6% 2	3734
	11th to 20th	Night	24% 45% 8% 10% 12% 2	3587
	21st to end	Night	35% 42% 4 6% 8% 5%	3644
April	1st to 10th	Night	20% 65% 3 5% 5% 2	1900
	11th to 20th	Night	15% 66% 4 7% 7% 1	1835
	21st to end	Night	17% 65% 3 6% 8% 1	1710
May	1st to 10th	Night	35% 45% 9% 9% 3	2840
	11th to 20th	Night	35% 46% 10% 6% 3	2814
	21st to end	Night	25% 44% 9% 12% 9% 1	2743
June	1st to 10th	Night	15% 66% 4 8% 7%	1520
	11th to 20th	Night	13% 67% 5% 9% 6%	1520
	21st to end	Night	15% 64% 3 9% 7% 1	1520
July	1st to 10th	Night	27% 39% 8% 13% 13%	2480
	11th to 20th	Night	25% 40% 11% 14% 10%	2472
	21st to end	Night	34% 37% 8% 11% 10% 1	2651
August	1st to 10th	Night	35% 40% 8% 11% 6% 1	2777
	11th to 20th	Night	28% 41% 10% 15% 5%	2809
	21st to end	Night	16% 39% 11% 17% 17%	3463
September	1st to 10th	Night	13% 61% 5% 12% 8% 1	1924
	11th to 20th	Night	16% 60% 3 9% 11% 1	2090
	21st to end	Night	17% 60% 4 10% 8%	2090
October	1st to 10th	Night	26% 38% 10% 17% 8% 1	3480
	11th to 20th	Night	12% 37% 7% 18% 24% 2	3852
	21st to end	Night	18% 37% 7% 23% 13% 1	4467
November	1st to 10th	Night	18% 57% 4 11% 9% 1	2537
	11th to 20th	Night	16% 59% 4 9% 10% 2	2477
	21st to end	Night	14% 61% 6% 12% 6% 1	2470
December	1st to 10th	Night	20% 61% 5% 8% 6%	2598
	11th to 20th	Night	22% 50% 6% 9% 12% 1	3288
	21st to end	Night	32% 39% 8% 15% 6%	4884

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	24% 11% 29% 30% 6% 1	180
	11th to 20th	Day	17% 18% 32% 26% 7%	180
	21st to end	Day	22% 7% 36% 26% 10%	198
February	1st to 10th	Day	25% 11% 35% 25% 3	382
	11th to 20th	Day	20% 10% 45% 22% 3	456
	21st to end	Day	18% 10% 33% 31% 7% 1	382
March	1st to 10th	Day	20% 10% 33% 29% 8%	460
	11th to 20th	Day	16% 9% 35% 34% 6%	460
	21st to end	Day	24% 8% 32% 26% 7% 3	506
April	1st to 10th	Day	23% 9% 31% 25% 10% 2	460
	11th to 20th	Day	20% 5% 28% 37% 10%	452
	21st to end	Day	22% 5% 23% 39% 10% 1	460
May	1st to 10th	Day	25% 5% 25% 33% 11% 1	463
	11th to 20th	Day	15% 4 22% 41% 14% 3	487
	21st to end	Day	17% 2 15% 40% 22% 4	529
June	1st to 10th	Day	18% 3 14% 38% 23% 3	490
	11th to 20th	Day	14% 3 17% 43% 19% 3	490
	21st to end	Day	15% 4 16% 39% 22% 4	490
July	1st to 10th	Day	16% 2 11% 36% 29% 6%	485
	11th to 20th	Day	11% 3 13% 37% 30% 6%	484
	21st to end	Day	11% 2 10% 44% 32% 2	532
August	1st to 10th	Day	11% 3 12% 37% 33% 5%	486
	11th to 20th	Day	13% 2 12% 37% 28% 8%	479
	21st to end	Day	12% 3 9% 39% 28% 8%	539
September	1st to 10th	Day	15% 3 17% 31% 25% 9%	490
	11th to 20th	Day	18% 3 18% 30% 22% 9%	490
	21st to end	Day	19% 3 20% 34% 17% 7%	490
October	1st to 10th	Day	23% 3 21% 30% 20% 4	490
	11th to 20th	Day	16% 6% 27% 29% 18% 3	422
	21st to end	Day	25% 5% 29% 29% 11% 1	429
November	1st to 10th	Day	14% 10% 28% 31% 14% 3	395
	11th to 20th	Day	23% 11% 32% 26% 8% 1	370
	21st to end	Day	23% 11% 28% 26% 11% 1	370
December	1st to 10th	Day	21% 7% 40% 24% 7%	237
	11th to 20th	Day	19% 10% 41% 26% 3	180
	21st to end	Day	23% 11% 33% 25% 6% 2	198
January	1st to 10th	Night	21% 14% 41% 21% 4	760
	11th to 20th	Night	25% 14% 37% 20% 3	760
	21st to end	Night	19% 13% 41% 23% 4	836
February	1st to 10th	Night	21% 13% 39% 25% 2	760
	11th to 20th	Night	20% 13% 48% 17% 3	743
	21st to end	Night	21% 12% 38% 22% 6%	628
March	1st to 10th	Night	22% 11% 37% 25% 4	760
	11th to 20th	Night	20% 8% 40% 24% 7% 1	760
	21st to end	Night	23% 8% 35% 25% 8%	836
April	1st to 10th	Night	23% 7% 31% 31% 8%	760
	11th to 20th	Night	20% 5% 32% 33% 10%	711
	21st to end	Night	22% 4 28% 35% 11% 1	570
May	1st to 10th	Night	24% 5% 25% 33% 11% 2	570
	11th to 20th	Night	22% 2 23% 37% 13% 1	562
	21st to end	Night	21% 4 15% 41% 18% 1	415
June	1st to 10th	Night	21% 3 16% 40% 17% 3	380
	11th to 20th	Night	18% 3 18% 40% 19% 2	380
	21st to end	Night	20% 2 14% 46% 16% 2	380
July	1st to 10th	Night	14% 3 12% 42% 26% 4	370
	11th to 20th	Night	12% 3 10% 45% 27% 3	368
	21st to end	Night	15% 2 9% 44% 28% 1	416
August	1st to 10th	Night	10% 3 11% 45% 29% 3	542
	11th to 20th	Night	12% 2 13% 43% 27% 2	562
	21st to end	Night	13% 3 14% 34% 30% 5%	823
September	1st to 10th	Night	13% 3 17% 38% 27% 3	760
	11th to 20th	Night	15% 4 19% 32% 23% 7%	760
	21st to end	Night	19% 2 19% 34% 22% 4	760
October	1st to 10th	Night	22% 4 22% 29% 18% 4	760
	11th to 20th	Night	17% 6% 30% 31% 14% 2	760
	21st to end	Night	24% 8% 31% 27% 9% 1	836
November	1st to 10th	Night	17% 7% 33% 31% 11% 2	780
	11th to 20th	Night	21% 11% 35% 24% 8% 1	763
	21st to end	Night	19% 16% 34% 25% 6% 1	760
December	1st to 10th	Night	24% 12% 40% 19% 5%	760
	11th to 20th	Night	22% 14% 38% 21% 4	760
	21st to end	Night	24% 13% 39% 22% 2	836

Page generated at 2024-11-08 06:44:46. Version ac07

Copyright © 2024 Attilla Danko.