Daytona Beach
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Daytona Beach clear sky chart from 2005-11-06 to 2025-08-05.

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	8% 5% 2 6% 5% 5% 6% 5% 7% 10% 41%	125429
	Night	9% 6% 2 6% 5% 5% 5% 4 7% 9% 43%	122652
Transparency	Day	20% 42% 14% 14% 8% 2	129111
	Night	22% 41% 11% 13% 9% 3	127039
Seeing	Day	9% 3 11% 25% 32% 21%	16636
	Night	10% 3 14% 29% 33% 12%	26705

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	8% 6% 2 5% 4 3 3 4 5% 8% 52%	4056
	11th to 20th	Day	19% 10% 3 9% 5% 4 4 4 5% 6% 31%	4060
	21st to end	Day	14% 6% 2 5% 3 4 4 3 5% 8% 45%	4466
February	1st to 10th	Day	11% 7% 2 6% 4 5% 5% 4 6% 8% 40%	1980
	11th to 20th	Day	9% 6% 2 6% 5% 4 4 3 4 7% 50%	1948
	21st to end	Day	9% 5% 2 6% 4 3 4 4 6% 8% 46%	1797
March	1st to 10th	Day	8% 6% 2 8% 5% 6% 5% 4 6% 9% 41%	4935
	11th to 20th	Day	4 3 2 4 3 4 3 3 5% 8% 61%	4980
	21st to end	Day	10% 5% 2 6% 4 4 5% 4 6% 8% 46%	5465
April	1st to 10th	Day	6% 4 2 5% 4 4 4 4 7% 9% 50%	2200
	11th to 20th	Day	7% 5% 2 7% 5% 5% 5% 4 7% 9% 43%	2271
	21st to end	Day	4 4 1 5% 4 4 4 4 8% 10% 52%	2400
May	1st to 10th	Day	4 3 1 4 4 4 5% 5% 7% 12% 50%	5667
	11th to 20th	Day	8% 4 2 6% 5% 5% 6% 4 7% 8% 45%	5861
	21st to end	Day	4 3 2 5% 4 5% 6% 5% 9% 12% 45%	6433
June	1st to 10th	Day	9% 6% 3 8% 7% 6% 8% 6% 9% 11% 28%	2600
	11th to 20th	Day	6% 5% 2 7% 6% 7% 8% 7% 9% 11% 32%	2600
	21st to end	Day	8% 6% 2 7% 7% 6% 8% 6% 8% 11% 30%	2600
July	1st to 10th	Day	8% 5% 2 8% 6% 6% 8% 7% 11% 13% 26%	5900
	11th to 20th	Day	4 4 2 6% 5% 5% 7% 6% 9% 15% 36%	5900
	21st to end	Day	4 4 1 5% 5% 6% 6% 5% 9% 12% 42%	6424
August	1st to 10th	Day	6% 6% 2 8% 6% 6% 7% 6% 9% 13% 31%	4156
	11th to 20th	Day	4 3 2 6% 5% 6% 7% 7% 10% 14% 36%	3897
	21st to end	Day	7% 5% 3 7% 5% 6% 7% 5% 9% 13% 32%	3910
September	1st to 10th	Day	7% 7% 2 9% 7% 9% 9% 8% 9% 10% 23%	2090
	11th to 20th	Day	9% 6% 4 7% 6% 7% 7% 6% 10% 12% 24%	2090
	21st to end	Day	11% 6% 3 9% 6% 5% 7% 6% 9% 10% 30%	2090
October	1st to 10th	Day	12% 7% 3 8% 6% 5% 5% 5% 6% 9% 33%	2021
	11th to 20th	Day	6% 6% 2 7% 5% 5% 4 4 8% 8% 45%	1900
	21st to end	Day	8% 5% 1 5% 4 5% 4 5% 7% 9% 46%	2090
November	1st to 10th	Day	8% 5% 2 8% 5% 5% 5% 5% 7% 8% 42%	1957
	11th to 20th	Day	10% 7% 2 7% 6% 5% 5% 4 7% 9% 37%	2000
	21st to end	Day	10% 7% 2 7% 5% 5% 4 4 6% 8% 42%	1916
December	1st to 10th	Day	6% 4 1 5% 3 4 4 3 6% 8% 56%	2930
	11th to 20th	Day	10% 7% 3 7% 6% 6% 6% 5% 7% 9% 35%	3373
	21st to end	Day	13% 7% 2 8% 5% 4 5% 4 6% 7% 40%	4466
January	1st to 10th	Night	9% 6% 2 5% 3 4 3 3 5% 7% 54%	5889
	11th to 20th	Night	19% 9% 3 8% 5% 4 4 4 6% 7% 32%	5900
	21st to end	Night	15% 6% 2 6% 4 4 4 4 5% 8% 42%	6490
February	1st to 10th	Night	12% 7% 2 6% 5% 4 5% 3 5% 7% 44%	2417
	11th to 20th	Night	10% 5% 2 6% 4 4 5% 4 5% 7% 48%	2338
	21st to end	Night	8% 5% 1 5% 4 4 4 3 6% 9% 50%	1830
March	1st to 10th	Night	12% 7% 2 6% 4 4 5% 3 6% 7% 44%	4918
	11th to 20th	Night	6% 4 1 3 3 3 4 4 6% 10% 57%	4980
	21st to end	Night	8% 6% 2 6% 4 5% 5% 4 5% 7% 47%	5467
April	1st to 10th	Night	7% 5% 2 5% 4 5% 4 4 6% 9% 51%	2200
	11th to 20th	Night	7% 5% 2 7% 5% 4 4 4 6% 7% 50%	2075
	21st to end	Night	5% 4 2 5% 4 3 5% 3 6% 9% 53%	2000
May	1st to 10th	Night	4 3 2 5% 4 4 4 4 7% 9% 54%	4269
	11th to 20th	Night	8% 5% 2 6% 4 5% 4 4 7% 10% 46%	4032
	21st to end	Night	5% 3 2 5% 4 4 4 5% 8% 12% 48%	4421
June	1st to 10th	Night	9% 6% 2 7% 5% 4 6% 5% 8% 13% 35%	1800
	11th to 20th	Night	5% 5% 3 7% 6% 6% 6% 6% 9% 13% 34%	1800
	21st to end	Night	6% 7% 2 8% 5% 5% 6% 6% 10% 11% 34%	1800
July	1st to 10th	Night	8% 5% 3 7% 6% 6% 7% 6% 9% 14% 29%	4058
	11th to 20th	Night	3 3 2 6% 5% 5% 7% 5% 9% 15% 41%	4057
	21st to end	Night	5% 4 2 7% 6% 6% 6% 4 7% 13% 40%	4427
August	1st to 10th	Night	5% 5% 3 10% 6% 6% 6% 5% 8% 12% 34%	2861
	11th to 20th	Night	3 3 2 6% 5% 5% 6% 6% 8% 15% 41%	2899
	21st to end	Night	7% 5% 3 7% 6% 5% 6% 6% 9% 13% 35%	3727
September	1st to 10th	Night	8% 6% 3 9% 6% 8% 8% 6% 9% 10% 27%	2090
	11th to 20th	Night	10% 8% 3 9% 6% 6% 7% 6% 8% 11% 27%	2090
	21st to end	Night	11% 7% 2 8% 6% 5% 5% 5% 7% 10% 34%	2090
October	1st to 10th	Night	10% 7% 3 9% 6% 5% 6% 4 7% 8% 33%	2156
	11th to 20th	Night	6% 5% 2 6% 4 5% 4 5% 7% 9% 49%	2280
	21st to end	Night	9% 5% 2 5% 4 5% 5% 3 6% 8% 48%	2508
November	1st to 10th	Night	9% 6% 2 6% 5% 5% 5% 5% 6% 8% 42%	2341
	11th to 20th	Night	9% 6% 3 7% 5% 5% 5% 5% 7% 8% 41%	2400
	21st to end	Night	9% 6% 3 6% 5% 6% 5% 4 6% 9% 40%	2480
December	1st to 10th	Night	5% 3 2 5% 4 4 4 4 5% 7% 56%	4250
	11th to 20th	Night	13% 8% 2 7% 5% 5% 4 3 6% 7% 40%	4822
	21st to end	Night	13% 8% 3 8% 5% 4 5% 4 5% 7% 38%	6490

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% 27% 9% 10% 22% 9%	4057
	11th to 20th	Day	45% 27% 4 9% 10% 4	4060
	21st to end	Day	26% 31% 6% 21% 10% 5%	4466
February	1st to 10th	Day	15% 63% 6% 6% 8% 2	1980
	11th to 20th	Day	11% 62% 5% 10% 10% 3	1958
	21st to end	Day	15% 62% 5% 7% 8% 4	1797
March	1st to 10th	Day	31% 34% 10% 11% 13% 2	4935
	11th to 20th	Day	13% 30% 8% 18% 19% 13%	4980
	21st to end	Day	25% 31% 8% 18% 12% 5%	5465
April	1st to 10th	Day	10% 64% 6% 11% 7% 3	2200
	11th to 20th	Day	11% 64% 4 9% 10% 3	2271
	21st to end	Day	9% 62% 6% 11% 10% 1	2400
May	1st to 10th	Day	15% 36% 21% 20% 6% 2	5699
	11th to 20th	Day	24% 33% 12% 25% 6% 1	5865
	21st to end	Day	13% 33% 16% 28% 9% 1	6447
June	1st to 10th	Day	14% 66% 10% 7% 2	2600
	11th to 20th	Day	13% 67% 10% 9% 1	2600
	21st to end	Day	11% 65% 15% 6% 2	2600
July	1st to 10th	Day	26% 36% 28% 8% 1	5835
	11th to 20th	Day	17% 34% 39% 10%	5831
	21st to end	Day	18% 34% 29% 18% 2	6240
August	1st to 10th	Day	24% 43% 24% 7% 1	4143
	11th to 20th	Day	14% 45% 21% 16% 4	3936
	21st to end	Day	18% 44% 22% 15% 1	3910
September	1st to 10th	Day	18% 68% 8% 3 3 1	2090
	11th to 20th	Day	17% 65% 11% 7% 1	2090
	21st to end	Day	14% 63% 9% 9% 4	2090
October	1st to 10th	Day	37% 41% 10% 7% 4	3359
	11th to 20th	Day	15% 38% 6% 15% 21% 5%	3140
	21st to end	Day	12% 37% 7% 19% 22% 3	3428
November	1st to 10th	Day	16% 58% 9% 10% 6% 2	1957
	11th to 20th	Day	19% 59% 4 8% 7% 3	2000
	21st to end	Day	18% 57% 4 11% 7% 3	1916
December	1st to 10th	Day	14% 37% 12% 19% 14% 4	2930
	11th to 20th	Day	29% 35% 8% 10% 14% 4	3370
	21st to end	Day	33% 30% 9% 16% 9% 3	4466
January	1st to 10th	Night	22% 27% 6% 14% 23% 8%	5889
	11th to 20th	Night	42% 27% 7% 11% 11% 1	5900
	21st to end	Night	28% 31% 6% 18% 12% 5%	6490
February	1st to 10th	Night	14% 63% 6% 7% 7% 3	2417
	11th to 20th	Night	13% 61% 4 10% 10% 2	2339
	21st to end	Night	12% 63% 6% 7% 7% 4	1830
March	1st to 10th	Night	32% 32% 8% 9% 13% 5%	4918
	11th to 20th	Night	15% 31% 10% 17% 14% 13%	4980
	21st to end	Night	25% 32% 8% 15% 15% 5%	5467
April	1st to 10th	Night	11% 64% 6% 11% 5% 3	2200
	11th to 20th	Night	11% 63% 4 11% 8% 3	2075
	21st to end	Night	10% 63% 6% 11% 8% 2	2000
May	1st to 10th	Night	17% 34% 18% 22% 7% 2	4299
	11th to 20th	Night	23% 33% 15% 22% 7%	4033
	21st to end	Night	16% 33% 17% 25% 9% 1	4429
June	1st to 10th	Night	14% 65% 13% 7% 1	1800
	11th to 20th	Night	15% 66% 10% 8% 1	1800
	21st to end	Night	13% 65% 11% 9% 2	1800
July	1st to 10th	Night	31% 36% 24% 8% 1	4015
	11th to 20th	Night	17% 35% 38% 9% 1	4006
	21st to end	Night	25% 32% 23% 18% 2	4297
August	1st to 10th	Night	28% 41% 24% 6% 1	2850
	11th to 20th	Night	15% 43% 19% 18% 4	2926
	21st to end	Night	20% 43% 23% 13% 1	3727
September	1st to 10th	Night	20% 65% 7% 5% 4	2090
	11th to 20th	Night	16% 63% 11% 7% 3	2090
	21st to end	Night	16% 63% 7% 11% 4 1	2090
October	1st to 10th	Night	41% 41% 7% 6% 4	3598
	11th to 20th	Night	18% 38% 4 14% 21% 4	3779
	21st to end	Night	16% 38% 5% 16% 24% 2	4120
November	1st to 10th	Night	17% 58% 7% 10% 6% 2	2341
	11th to 20th	Night	19% 58% 5% 7% 8% 3	2400
	21st to end	Night	18% 58% 4 10% 7% 3	2480
December	1st to 10th	Night	17% 36% 10% 21% 9% 8%	4250
	11th to 20th	Night	27% 35% 10% 13% 10% 6%	4824
	21st to end	Night	34% 30% 10% 15% 8% 3	6490

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	13% 3 24% 45% 14% 1	300
	11th to 20th	Day	10% 5% 27% 35% 19% 5%	300
	21st to end	Day	15% 6% 25% 45% 10%	330
February	1st to 10th	Day	15% 5% 17% 35% 25% 3	300
	11th to 20th	Day	12% 5% 17% 40% 21% 4	300
	21st to end	Day	10% 2 20% 38% 24% 5%	396
March	1st to 10th	Day	7% 4 23% 43% 20% 2	500
	11th to 20th	Day	11% 3 22% 35% 24% 5%	500
	21st to end	Day	10% 3 16% 39% 26% 5%	550
April	1st to 10th	Day	9% 5% 19% 38% 25% 4	500
	11th to 20th	Day	8% 2 17% 35% 29% 9%	492
	21st to end	Day	5% 2 9% 34% 36% 13%	500
May	1st to 10th	Day	5% 2 10% 36% 36% 11%	503
	11th to 20th	Day	8% 2 7% 25% 39% 18%	527
	21st to end	Day	7% 1 4 16% 44% 28%	573
June	1st to 10th	Day	11% 2 3 19% 42% 23%	530
	11th to 20th	Day	7% 2 4 12% 37% 39%	530
	21st to end	Day	5% 1 3 10% 36% 45%	530
July	1st to 10th	Day	6% 2 1 6% 32% 53%	525
	11th to 20th	Day	6% 1 3 34% 56%	524
	21st to end	Day	6% 1 1 7% 37% 47%	576
August	1st to 10th	Day	6% 1 3 9% 35% 46%	502
	11th to 20th	Day	4 1 1 6% 29% 60%	479
	21st to end	Day	9% 2 2 6% 35% 46%	539
September	1st to 10th	Day	9% 2 5% 8% 37% 40%	490
	11th to 20th	Day	10% 2 3 14% 43% 28%	490
	21st to end	Day	10% 3 6% 14% 37% 30%	490
October	1st to 10th	Day	17% 3 8% 30% 32% 10%	490
	11th to 20th	Day	6% 3 11% 29% 41% 10%	490
	21st to end	Day	9% 2 8% 31% 42% 7%	539
November	1st to 10th	Day	10% 6% 14% 27% 35% 9%	495
	11th to 20th	Day	15% 3 15% 35% 27% 5%	500
	21st to end	Day	12% 2 20% 35% 25% 5%	416
December	1st to 10th	Day	7% 2 19% 38% 28% 5%	300
	11th to 20th	Day	11% 3 22% 36% 24% 4	300
	21st to end	Day	11% 3 15% 36% 30% 5%	330
January	1st to 10th	Night	13% 7% 27% 36% 15% 2	800
	11th to 20th	Night	13% 5% 26% 36% 19% 3	800
	21st to end	Night	15% 6% 30% 36% 13%	880
February	1st to 10th	Night	16% 5% 19% 37% 20% 3	800
	11th to 20th	Night	13% 5% 25% 39% 17% 2	783
	21st to end	Night	12% 3 20% 45% 18% 3	660
March	1st to 10th	Night	6% 5% 24% 44% 19% 2	800
	11th to 20th	Night	9% 4 20% 41% 22% 5%	800
	21st to end	Night	8% 3 20% 38% 28% 3	880
April	1st to 10th	Night	8% 3 20% 40% 25% 4	800
	11th to 20th	Night	7% 3 16% 40% 30% 3	791
	21st to end	Night	7% 2 14% 36% 34% 6%	800
May	1st to 10th	Night	6% 1 13% 36% 39% 5%	709
	11th to 20th	Night	8% 2 9% 31% 40% 10%	591
	21st to end	Night	7% 2 5% 21% 48% 17%	650
June	1st to 10th	Night	10% 2 4 22% 51% 12%	600
	11th to 20th	Night	8% 1 5% 15% 42% 30%	600
	21st to end	Night	8% 1 2 14% 47% 29%	600
July	1st to 10th	Night	8% 3 2 10% 41% 36%	585
	11th to 20th	Night	6% 1 2 6% 44% 41%	582
	21st to end	Night	5% 1 3 9% 50% 32%	657
August	1st to 10th	Night	8% 1 3 10% 45% 34%	579
	11th to 20th	Night	4 1 2 8% 46% 39%	626
	21st to end	Night	10% 2 4 11% 42% 31%	836
September	1st to 10th	Night	12% 2 4 9% 46% 28%	760
	11th to 20th	Night	12% 2 5% 18% 44% 19%	760
	21st to end	Night	14% 3 4 16% 43% 21%	760
October	1st to 10th	Night	15% 2 9% 27% 37% 10%	760
	11th to 20th	Night	8% 2 11% 29% 42% 8%	760
	21st to end	Night	11% 2 10% 31% 40% 5%	836
November	1st to 10th	Night	12% 3 15% 31% 32% 7%	780
	11th to 20th	Night	13% 4 16% 38% 25% 5%	800
	21st to end	Night	11% 4 21% 38% 22% 4	800
December	1st to 10th	Night	10% 4 19% 34% 28% 6%	800
	11th to 20th	Night	14% 6% 20% 30% 25% 6%	800
	21st to end	Night	13% 4 21% 33% 26% 3	880

Page generated at 2025-08-02 01:32:26. Version ac07

Copyright © 2025 Attilla Danko.