Applewood Absurditory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Applewood Absurditory clear sky chart from 2005-11-06 to 2024-04-03.

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% 9% 4 7% 6% 4 5% 5% 5% 7% 33%	78575
	Night	16% 10% 4 7% 6% 3 5% 5% 5% 6% 34%	81574
Transparency	Day	48% 8% 12% 19% 11% 1	78286
	Night	49% 7% 12% 19% 11% 1	81384
Seeing	Day	17% 11% 28% 24% 14% 6%	14590
	Night	19% 9% 29% 29% 12% 1	24759

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	16% 17% 6% 10% 6% 5% 5% 5% 5% 5% 21%	2527
	11th to 20th	Day	16% 17% 7% 10% 9% 4 7% 6% 5% 7% 12%	2530
	21st to end	Day	27% 19% 7% 11% 6% 3 3 3 3 4 13%	3067
February	1st to 10th	Day	15% 13% 6% 9% 9% 4 7% 5% 6% 5% 22%	1710
	11th to 20th	Day	15% 10% 5% 11% 9% 5% 5% 4 4 6% 25%	1811
	21st to end	Day	15% 14% 5% 9% 6% 3 4 5% 5% 6% 27%	1570
March	1st to 10th	Day	15% 12% 5% 7% 6% 4 4 5% 6% 7% 28%	1933
	11th to 20th	Day	14% 10% 4 8% 7% 3 4 3 5% 8% 34%	2090
	21st to end	Day	20% 11% 4 8% 7% 3 5% 4 4 7% 27%	2299
April	1st to 10th	Day	17% 11% 4 8% 6% 4 4 4 5% 7% 31%	2124
	11th to 20th	Day	17% 9% 3 7% 5% 3 5% 5% 5% 7% 34%	2266
	21st to end	Day	19% 8% 3 6% 6% 3 4 4 5% 7% 34%	2340
May	1st to 10th	Day	17% 8% 4 6% 7% 4 4 5% 5% 8% 32%	2340
	11th to 20th	Day	19% 9% 3 6% 5% 4 5% 4 4 7% 34%	2301
	21st to end	Day	11% 6% 3 5% 6% 3 5% 5% 6% 9% 41%	2531
June	1st to 10th	Day	10% 5% 3 5% 6% 4 4 5% 6% 8% 41%	2506
	11th to 20th	Day	11% 5% 2 5% 5% 4 5% 5% 8% 11% 39%	2520
	21st to end	Day	10% 4 2 6% 6% 3 7% 6% 7% 9% 39%	2520
July	1st to 10th	Day	7% 5% 2 5% 5% 4 5% 5% 7% 9% 47%	2520
	11th to 20th	Day	9% 4 2 5% 5% 4 5% 6% 6% 10% 44%	2520
	21st to end	Day	8% 5% 3 5% 6% 4 6% 6% 6% 9% 43%	2592
August	1st to 10th	Day	7% 5% 2 5% 7% 4 6% 6% 6% 8% 43%	2327
	11th to 20th	Day	10% 5% 3 7% 6% 4 6% 6% 7% 9% 38%	2303
	21st to end	Day	9% 5% 3 5% 5% 3 6% 6% 7% 10% 42%	2530
September	1st to 10th	Day	12% 5% 3 5% 6% 4 5% 6% 6% 9% 40%	2042
	11th to 20th	Day	9% 5% 2 5% 5% 3 5% 6% 6% 10% 45%	1980
	21st to end	Day	14% 5% 3 5% 6% 3 5% 5% 5% 9% 39%	1980
October	1st to 10th	Day	12% 6% 3 5% 5% 4 4 5% 5% 8% 41%	1942
	11th to 20th	Day	18% 8% 3 7% 6% 4 6% 5% 5% 6% 33%	1800
	21st to end	Day	19% 10% 3 7% 6% 4 4 5% 5% 7% 32%	1828
November	1st to 10th	Day	12% 7% 3 8% 6% 3 4 4 6% 7% 39%	1672
	11th to 20th	Day	15% 12% 4 7% 6% 3 6% 4 5% 6% 31%	1710
	21st to end	Day	19% 10% 5% 8% 7% 3 5% 5% 5% 6% 29%	1687
December	1st to 10th	Day	15% 13% 7% 11% 8% 3 5% 5% 5% 6% 21%	1520
	11th to 20th	Day	16% 14% 6% 8% 6% 4 4 5% 6% 7% 23%	1854
	21st to end	Day	25% 21% 7% 10% 7% 3 4 4 3 5% 11%	2783
January	1st to 10th	Night	16% 16% 6% 9% 7% 3 4 4 4 5% 24%	4428
	11th to 20th	Night	15% 18% 8% 12% 6% 4 5% 6% 5% 6% 15%	4440
	21st to end	Night	25% 16% 8% 11% 6% 3 4 4 3 3 17%	4587
February	1st to 10th	Night	17% 14% 6% 10% 7% 4 5% 5% 4 5% 24%	2470
	11th to 20th	Night	14% 12% 6% 9% 7% 3 6% 4 4 7% 28%	2252
	21st to end	Night	19% 9% 4 9% 7% 3 4 4 4 6% 30%	1884
March	1st to 10th	Night	16% 8% 4 8% 6% 4 4 5% 5% 5% 35%	2246
	11th to 20th	Night	14% 8% 3 6% 5% 3 5% 5% 6% 7% 38%	2090
	21st to end	Night	19% 8% 4 6% 6% 3 5% 5% 4 6% 34%	2299
April	1st to 10th	Night	15% 9% 4 6% 6% 3 5% 5% 5% 7% 37%	1895
	11th to 20th	Night	18% 8% 2 5% 5% 3 5% 6% 6% 6% 37%	1643
	21st to end	Night	18% 8% 3 5% 5% 3 5% 5% 4 6% 39%	1620
May	1st to 10th	Night	17% 8% 4 6% 6% 4 5% 5% 4 8% 33%	1620
	11th to 20th	Night	19% 7% 2 5% 5% 3 4 5% 5% 7% 38%	1592
	21st to end	Night	10% 5% 2 5% 5% 2 5% 5% 6% 9% 45%	1744
June	1st to 10th	Night	12% 3 2 4 4 3 5% 5% 6% 9% 47%	1450
	11th to 20th	Night	10% 4 3 6% 5% 3 5% 5% 6% 8% 45%	1440
	21st to end	Night	9% 5% 3 5% 5% 2 4 5% 7% 8% 48%	1440
July	1st to 10th	Night	8% 3 3 3 5% 3 5% 4 5% 8% 54%	1440
	11th to 20th	Night	8% 5% 2 4 4 2 4 4 5% 9% 53%	1440
	21st to end	Night	5% 4 2 5% 4 3 5% 5% 7% 10% 51%	1724
August	1st to 10th	Night	7% 4 2 5% 4 3 5% 6% 5% 9% 50%	1611
	11th to 20th	Night	8% 5% 2 5% 5% 3 4 6% 6% 8% 49%	1598
	21st to end	Night	8% 4 2 5% 4 3 5% 4 5% 8% 51%	1822
September	1st to 10th	Night	9% 6% 2 5% 4 3 4 5% 6% 7% 49%	1899
	11th to 20th	Night	9% 6% 3 4 3 3 5% 3 5% 8% 52%	1980
	21st to end	Night	13% 5% 2 6% 4 3 5% 5% 5% 7% 45%	1980
October	1st to 10th	Night	13% 6% 3 6% 5% 3 3 5% 4 6% 46%	2016
	11th to 20th	Night	17% 8% 4 7% 6% 3 4 5% 5% 6% 36%	2160
	21st to end	Night	21% 8% 3 7% 5% 3 5% 4 4 6% 34%	2524
November	1st to 10th	Night	13% 8% 3 5% 5% 3 5% 4 5% 7% 43%	2406
	11th to 20th	Night	16% 10% 4 6% 6% 4 5% 4 6% 7% 32%	2470
	21st to end	Night	19% 12% 5% 6% 5% 3 4 4 5% 6% 30%	2488
December	1st to 10th	Night	18% 13% 7% 9% 7% 3 6% 5% 4 6% 23%	2660
	11th to 20th	Night	15% 14% 5% 10% 7% 3 5% 5% 5% 6% 24%	3332
	21st to end	Night	28% 20% 5% 9% 5% 3 4 4 4 4 12%	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	62% 9% 12% 12% 5%	2528
	11th to 20th	Day	68% 9% 12% 8% 3	2530
	21st to end	Day	75% 6% 8% 7% 3 1	3067
February	1st to 10th	Day	61% 8% 10% 13% 7%	1710
	11th to 20th	Day	57% 8% 10% 16% 7% 1	1821
	21st to end	Day	56% 8% 13% 15% 6% 2	1570
March	1st to 10th	Day	54% 7% 13% 17% 8% 1	1933
	11th to 20th	Day	49% 6% 12% 19% 11% 3	2090
	21st to end	Day	57% 7% 10% 19% 6% 1	2299
April	1st to 10th	Day	53% 7% 11% 17% 11%	2124
	11th to 20th	Day	48% 8% 11% 19% 12% 2	2266
	21st to end	Day	49% 7% 13% 16% 14% 1	2340
May	1st to 10th	Day	50% 7% 12% 19% 10% 2	2340
	11th to 20th	Day	50% 7% 10% 18% 14% 2	2305
	21st to end	Day	39% 8% 14% 24% 13% 2	2531
June	1st to 10th	Day	37% 9% 13% 25% 14% 3	2506
	11th to 20th	Day	37% 9% 14% 20% 17% 2	2520
	21st to end	Day	36% 11% 14% 21% 15% 3	2520
July	1st to 10th	Day	32% 9% 13% 24% 19% 4	2451
	11th to 20th	Day	33% 9% 15% 24% 18% 2	2445
	21st to end	Day	34% 10% 13% 24% 17% 2	2448
August	1st to 10th	Day	34% 8% 16% 27% 13% 1	2314
	11th to 20th	Day	39% 11% 13% 22% 14% 2	2303
	21st to end	Day	35% 9% 13% 24% 17% 2	2530
September	1st to 10th	Day	39% 10% 17% 19% 14% 2	2042
	11th to 20th	Day	33% 8% 12% 32% 14% 1	1980
	21st to end	Day	39% 8% 14% 24% 14%	1980
October	1st to 10th	Day	39% 7% 12% 26% 13% 2	1942
	11th to 20th	Day	50% 6% 13% 19% 11%	1800
	21st to end	Day	52% 7% 13% 18% 10% 1	1828
November	1st to 10th	Day	43% 7% 12% 24% 13% 1	1672
	11th to 20th	Day	53% 6% 13% 18% 9% 2	1710
	21st to end	Day	55% 7% 13% 17% 7%	1687
December	1st to 10th	Day	61% 8% 12% 13% 4	1520
	11th to 20th	Day	58% 9% 14% 14% 4	1851
	21st to end	Day	77% 6% 8% 6% 3	2783
January	1st to 10th	Night	59% 8% 11% 15% 6% 1	4428
	11th to 20th	Night	66% 8% 13% 10% 4	4440
	21st to end	Night	70% 7% 10% 10% 3 1	4587
February	1st to 10th	Night	61% 7% 11% 13% 6% 1	2470
	11th to 20th	Night	56% 6% 10% 18% 8% 1	2253
	21st to end	Night	55% 6% 12% 18% 8% 2	1884
March	1st to 10th	Night	49% 7% 12% 21% 10% 1	2246
	11th to 20th	Night	43% 8% 12% 20% 16% 2	2090
	21st to end	Night	50% 6% 10% 22% 10% 1	2299
April	1st to 10th	Night	46% 7% 11% 20% 14% 2	1895
	11th to 20th	Night	43% 8% 11% 18% 18% 2	1643
	21st to end	Night	46% 7% 13% 17% 15% 3	1620
May	1st to 10th	Night	49% 6% 12% 19% 11% 2	1620
	11th to 20th	Night	45% 6% 10% 19% 17% 2	1593
	21st to end	Night	34% 9% 15% 25% 15% 3	1745
June	1st to 10th	Night	33% 7% 12% 28% 18% 3	1450
	11th to 20th	Night	35% 9% 12% 25% 16% 2	1440
	21st to end	Night	32% 8% 13% 25% 20% 1	1440
July	1st to 10th	Night	29% 7% 13% 28% 20% 4	1400
	11th to 20th	Night	28% 7% 14% 28% 20% 3	1392
	21st to end	Night	26% 9% 17% 24% 20% 4	1628
August	1st to 10th	Night	29% 9% 15% 29% 17% 2	1600
	11th to 20th	Night	30% 10% 15% 28% 13% 3	1598
	21st to end	Night	31% 8% 13% 26% 20% 2	1822
September	1st to 10th	Night	33% 9% 12% 27% 17% 2	1899
	11th to 20th	Night	30% 7% 11% 30% 21% 1	1980
	21st to end	Night	39% 7% 11% 28% 15% 1	1980
October	1st to 10th	Night	39% 6% 11% 24% 19% 1	2016
	11th to 20th	Night	48% 6% 12% 19% 13% 1	2160
	21st to end	Night	50% 6% 12% 22% 9% 1	2524
November	1st to 10th	Night	40% 7% 13% 24% 15% 1	2406
	11th to 20th	Night	49% 6% 15% 20% 9% 1	2470
	21st to end	Night	55% 7% 13% 18% 7%	2488
December	1st to 10th	Night	62% 7% 12% 13% 6%	2660
	11th to 20th	Night	58% 9% 13% 14% 6% 1	3334
	21st to end	Night	73% 8% 10% 7% 2	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% 16% 35% 18% 5% 1	270
	11th to 20th	Day	22% 15% 44% 15% 4 1	270
	21st to end	Day	30% 13% 32% 20% 4 1	297
February	1st to 10th	Day	23% 20% 37% 14% 3 1	270
	11th to 20th	Day	24% 17% 38% 17% 3	270
	21st to end	Day	26% 24% 36% 13% 1	225
March	1st to 10th	Day	24% 21% 34% 16% 4	303
	11th to 20th	Day	23% 12% 32% 25% 7% 1	460
	21st to end	Day	25% 15% 32% 22% 6% 1	506
April	1st to 10th	Day	22% 15% 32% 22% 9% 1	428
	11th to 20th	Day	22% 18% 32% 16% 8% 4	412
	21st to end	Day	25% 12% 31% 17% 11% 3	420
May	1st to 10th	Day	23% 13% 29% 21% 10% 4	423
	11th to 20th	Day	21% 10% 26% 23% 14% 6%	447
	21st to end	Day	14% 7% 21% 28% 21% 9%	485
June	1st to 10th	Day	11% 7% 28% 33% 17% 4	616
	11th to 20th	Day	13% 8% 28% 30% 17% 4	630
	21st to end	Day	12% 7% 29% 30% 16% 6%	630
July	1st to 10th	Day	8% 4 21% 29% 27% 11%	621
	11th to 20th	Day	11% 6% 24% 30% 22% 8%	618
	21st to end	Day	8% 4 24% 30% 23% 11%	533
August	1st to 10th	Day	7% 2 21% 27% 28% 15%	446
	11th to 20th	Day	12% 4 19% 29% 23% 13%	439
	21st to end	Day	12% 3 18% 29% 28% 11%	495
September	1st to 10th	Day	12% 6% 21% 25% 23% 13%	450
	11th to 20th	Day	9% 5% 16% 26% 28% 16%	450
	21st to end	Day	15% 10% 22% 22% 22% 9%	450
October	1st to 10th	Day	17% 8% 27% 22% 18% 8%	450
	11th to 20th	Day	18% 17% 28% 28% 8% 1	450
	21st to end	Day	26% 14% 35% 18% 6% 1	343
November	1st to 10th	Day	14% 18% 33% 23% 10% 2	270
	11th to 20th	Day	22% 18% 32% 20% 6% 2	270
	21st to end	Day	25% 15% 40% 14% 5%	259
December	1st to 10th	Day	20% 18% 39% 14% 6% 2	180
	11th to 20th	Day	23% 15% 44% 14% 3 1	207
	21st to end	Day	28% 19% 34% 17% 2	297
January	1st to 10th	Night	23% 14% 36% 21% 5% 1	950
	11th to 20th	Night	26% 13% 33% 22% 5% 1	950
	21st to end	Night	19% 13% 35% 27% 6%	865
February	1st to 10th	Night	24% 13% 35% 25% 3	760
	11th to 20th	Night	23% 14% 34% 26% 4	743
	21st to end	Night	24% 13% 38% 21% 3	628
March	1st to 10th	Night	21% 11% 34% 27% 6%	760
	11th to 20th	Night	17% 17% 36% 24% 6% 1	760
	21st to end	Night	22% 10% 31% 28% 7%	836
April	1st to 10th	Night	19% 14% 33% 30% 4 1	621
	11th to 20th	Night	22% 9% 34% 26% 8% 1	533
	21st to end	Night	22% 7% 30% 32% 8%	540
May	1st to 10th	Night	19% 9% 31% 30% 10% 1	540
	11th to 20th	Night	23% 3 26% 35% 12% 1	531
	21st to end	Night	12% 3 24% 35% 24% 3	584
June	1st to 10th	Night	13% 2 22% 48% 15% 1	540
	11th to 20th	Night	12% 4 21% 44% 19%	540
	21st to end	Night	11% 3 21% 43% 21% 1	540
July	1st to 10th	Night	8% 2 16% 40% 29% 4	525
	11th to 20th	Night	9% 3 18% 40% 26% 4	522
	21st to end	Night	5% 2 18% 47% 25% 3	591
August	1st to 10th	Night	9% 1 16% 42% 29% 2	537
	11th to 20th	Night	9% 2 17% 37% 32% 3	534
	21st to end	Night	9% 2 16% 38% 31% 4	594
September	1st to 10th	Night	12% 5% 17% 33% 27% 5%	639
	11th to 20th	Night	11% 4 17% 34% 30% 5%	720
	21st to end	Night	16% 5% 21% 30% 24% 4	720
October	1st to 10th	Night	15% 6% 26% 32% 18% 3	720
	11th to 20th	Night	21% 12% 30% 26% 9% 1	720
	21st to end	Night	25% 10% 33% 27% 6%	792
November	1st to 10th	Night	17% 11% 30% 28% 12% 1	740
	11th to 20th	Night	22% 13% 35% 22% 7% 1	760
	21st to end	Night	25% 13% 32% 22% 7%	760
December	1st to 10th	Night	24% 14% 35% 21% 6%	760
	11th to 20th	Night	23% 14% 37% 22% 4	859
	21st to end	Night	31% 13% 33% 20% 3	1045

Page generated at 2024-03-31 06:08:53. Version ac07

Copyright © 2024 Attilla Danko.