Pompano Beach
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Pompano Beach clear sky chart from 2005-11-06 to 2025-05-26.

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	7% 5% 2 7% 6% 6% 7% 6% 9% 12% 35%	114159
	Night	7% 5% 2 7% 5% 5% 6% 5% 8% 10% 40%	115129
Transparency	Day	19% 46% 13% 14% 6% 1	117856
	Night	22% 44% 12% 14% 7% 2	119571
Seeing	Day	7% 3 10% 25% 33% 22%	16775
	Night	8% 3 12% 28% 33% 15%	26958

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	7% 5% 2 5% 4 4 5% 4 6% 10% 48%	4056
	11th to 20th	Day	17% 9% 3 8% 6% 6% 5% 4 7% 9% 27%	4060
	21st to end	Day	10% 8% 3 8% 5% 5% 6% 4 6% 8% 38%	4484
February	1st to 10th	Day	8% 8% 2 6% 5% 4 6% 5% 7% 11% 39%	2000
	11th to 20th	Day	7% 5% 2 5% 4 4 4 4 7% 10% 47%	2084
	21st to end	Day	6% 5% 2 6% 5% 6% 6% 5% 7% 9% 43%	1815
March	1st to 10th	Day	5% 4 2 7% 5% 6% 7% 6% 8% 10% 40%	4935
	11th to 20th	Day	3 2 1 4 3 3 4 4 7% 11% 58%	4980
	21st to end	Day	7% 5% 2 6% 5% 5% 5% 5% 8% 10% 42%	5465
April	1st to 10th	Day	4 3 2 5% 4 5% 6% 6% 9% 12% 45%	2200
	11th to 20th	Day	7% 5% 2 5% 4 5% 5% 6% 8% 11% 41%	2289
	21st to end	Day	6% 3 2 5% 5% 5% 6% 7% 9% 11% 42%	2400
May	1st to 10th	Day	3 2 1 3 3 4 4 5% 7% 12% 56%	3885
	11th to 20th	Day	5% 5% 2 7% 6% 6% 7% 5% 9% 13% 35%	3898
	21st to end	Day	6% 5% 2 6% 5% 5% 7% 6% 9% 11% 40%	4541
June	1st to 10th	Day	13% 8% 3 11% 8% 8% 7% 7% 8% 10% 16%	2470
	11th to 20th	Day	7% 7% 3 10% 8% 9% 9% 9% 9% 11% 20%	2470
	21st to end	Day	6% 7% 3 9% 7% 7% 9% 7% 10% 13% 22%	2470
July	1st to 10th	Day	5% 6% 2 7% 6% 6% 6% 6% 9% 16% 32%	4120
	11th to 20th	Day	5% 5% 2 7% 6% 6% 7% 8% 11% 15% 27%	4120
	21st to end	Day	3 3 2 6% 6% 7% 7% 7% 11% 17% 32%	4466
August	1st to 10th	Day	4 4 3 9% 9% 9% 9% 7% 12% 13% 21%	3992
	11th to 20th	Day	4 5% 2 7% 5% 7% 8% 7% 11% 16% 28%	3730
	21st to end	Day	5% 4 2 8% 6% 7% 9% 7% 13% 18% 22%	3959
September	1st to 10th	Day	7% 5% 3 10% 7% 9% 9% 8% 10% 12% 20%	2090
	11th to 20th	Day	6% 6% 3 10% 9% 8% 8% 7% 10% 13% 21%	2090
	21st to end	Day	10% 9% 3 10% 8% 8% 9% 6% 8% 9% 20%	2090
October	1st to 10th	Day	9% 7% 3 9% 7% 7% 8% 7% 8% 13% 21%	1983
	11th to 20th	Day	10% 7% 3 8% 6% 7% 7% 6% 9% 12% 26%	1900
	21st to end	Day	11% 7% 3 8% 6% 5% 7% 5% 6% 10% 34%	2090
November	1st to 10th	Day	8% 6% 2 7% 5% 5% 6% 5% 9% 11% 36%	1957
	11th to 20th	Day	11% 6% 2 8% 8% 5% 6% 6% 7% 10% 30%	2000
	21st to end	Day	8% 5% 2 7% 7% 6% 7% 5% 7% 8% 38%	2000
December	1st to 10th	Day	6% 5% 2 4 4 4 4 5% 8% 8% 49%	3231
	11th to 20th	Day	9% 6% 3 7% 5% 5% 6% 5% 8% 10% 35%	3373
	21st to end	Day	12% 7% 3 8% 6% 6% 7% 5% 8% 10% 28%	4466
January	1st to 10th	Night	7% 5% 2 6% 5% 5% 6% 4 7% 9% 42%	5889
	11th to 20th	Night	16% 9% 4 9% 6% 5% 5% 4 6% 7% 30%	5900
	21st to end	Night	11% 8% 3 8% 5% 5% 5% 4 6% 7% 40%	6467
February	1st to 10th	Night	9% 6% 2 5% 4 4 4 5% 7% 10% 44%	2400
	11th to 20th	Night	6% 4 2 5% 4 4 5% 3 6% 8% 52%	2198
	21st to end	Night	6% 3 2 6% 4 4 5% 4 7% 8% 52%	1815
March	1st to 10th	Night	4 4 3 7% 4 5% 5% 4 7% 9% 49%	4918
	11th to 20th	Night	4 3 1 4 3 4 3 4 5% 10% 59%	4980
	21st to end	Night	6% 4 2 5% 5% 5% 5% 5% 7% 9% 47%	5467
April	1st to 10th	Night	4 3 2 4 3 4 4 5% 7% 11% 55%	2200
	11th to 20th	Night	5% 3 2 6% 4 5% 6% 4 7% 10% 49%	2058
	21st to end	Night	6% 5% 2 5% 5% 4 4 4 8% 11% 49%	2000
May	1st to 10th	Night	2 2 1 3 2 4 4 4 7% 10% 62%	3230
	11th to 20th	Night	5% 4 2 6% 4 5% 5% 5% 8% 10% 46%	3230
	21st to end	Night	6% 5% 2 5% 4 5% 5% 5% 8% 11% 43%	3141
June	1st to 10th	Night	11% 7% 3 9% 7% 7% 8% 5% 9% 10% 24%	1710
	11th to 20th	Night	7% 5% 3 7% 6% 7% 7% 6% 8% 13% 31%	1710
	21st to end	Night	4 6% 3 8% 6% 7% 6% 6% 11% 13% 31%	1710
July	1st to 10th	Night	3 5% 2 7% 7% 6% 6% 5% 8% 12% 39%	2840
	11th to 20th	Night	4 4 2 8% 5% 5% 6% 6% 10% 13% 36%	2840
	21st to end	Night	2 4 2 6% 6% 5% 5% 5% 8% 14% 42%	3087
August	1st to 10th	Night	4 4 2 7% 6% 7% 8% 6% 9% 13% 33%	2904
	11th to 20th	Night	2 3 2 6% 6% 7% 6% 6% 9% 14% 40%	3097
	21st to end	Night	5% 4 2 7% 5% 7% 9% 8% 14% 17% 23%	3690
September	1st to 10th	Night	6% 6% 3 8% 7% 6% 9% 8% 11% 11% 27%	2090
	11th to 20th	Night	8% 6% 3 9% 7% 7% 8% 6% 8% 12% 26%	2090
	21st to end	Night	9% 7% 4 9% 7% 8% 9% 6% 9% 10% 22%	2090
October	1st to 10th	Night	8% 7% 3 10% 7% 7% 7% 7% 9% 10% 24%	2194
	11th to 20th	Night	9% 6% 3 7% 6% 6% 6% 5% 7% 11% 34%	2280
	21st to end	Night	11% 6% 2 7% 5% 6% 6% 4 7% 8% 38%	2508
November	1st to 10th	Night	10% 6% 2 6% 5% 5% 5% 4 7% 9% 41%	2341
	11th to 20th	Night	9% 6% 3 8% 7% 6% 6% 6% 6% 8% 35%	2400
	21st to end	Night	9% 6% 2 7% 5% 5% 6% 4 7% 9% 41%	2400
December	1st to 10th	Night	8% 5% 2 5% 4 4 4 4 6% 8% 51%	3943
	11th to 20th	Night	11% 7% 3 8% 6% 5% 6% 4 7% 9% 33%	4822
	21st to end	Night	9% 8% 4 10% 7% 7% 6% 5% 8% 9% 28%	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	22% 29% 8% 23% 15% 3	4057
	11th to 20th	Day	40% 31% 11% 14% 4	4060
	21st to end	Day	31% 31% 5% 23% 7% 3	4484
February	1st to 10th	Day	11% 64% 9% 10% 5% 1	2000
	11th to 20th	Day	10% 61% 4 12% 11% 2	2094
	21st to end	Day	13% 63% 7% 7% 8% 2	1815
March	1st to 10th	Day	24% 36% 10% 14% 14% 2	4935
	11th to 20th	Day	8% 31% 13% 23% 15% 9%	4980
	21st to end	Day	23% 33% 11% 21% 10% 2	5465
April	1st to 10th	Day	7% 63% 8% 12% 8% 2	2200
	11th to 20th	Day	9% 64% 7% 8% 9% 3	2289
	21st to end	Day	8% 63% 5% 13% 10% 1	2400
May	1st to 10th	Day	8% 42% 11% 23% 12% 3	3920
	11th to 20th	Day	16% 44% 21% 16% 3	3902
	21st to end	Day	11% 44% 13% 25% 7%	4554
June	1st to 10th	Day	18% 70% 8% 4 1	2470
	11th to 20th	Day	17% 71% 7% 5%	2470
	21st to end	Day	11% 70% 15% 4	2470
July	1st to 10th	Day	16% 42% 27% 14%	4055
	11th to 20th	Day	22% 43% 28% 7%	4051
	21st to end	Day	17% 44% 28% 11%	4324
August	1st to 10th	Day	28% 47% 18% 6% 1	3979
	11th to 20th	Day	16% 46% 24% 14%	3766
	21st to end	Day	21% 46% 29% 4	3959
September	1st to 10th	Day	16% 67% 11% 6%	2090
	11th to 20th	Day	16% 64% 13% 5% 1	2090
	21st to end	Day	17% 67% 8% 7% 2	2090
October	1st to 10th	Day	28% 45% 14% 10% 2	3295
	11th to 20th	Day	30% 40% 12% 10% 7% 1	3140
	21st to end	Day	21% 39% 8% 21% 9% 2	3428
November	1st to 10th	Day	15% 60% 10% 10% 4 1	1957
	11th to 20th	Day	19% 59% 6% 8% 5% 2	2000
	21st to end	Day	16% 59% 7% 8% 8% 3	2000
December	1st to 10th	Day	15% 39% 11% 22% 10% 3	3231
	11th to 20th	Day	24% 36% 10% 14% 13% 3	3370
	21st to end	Day	37% 32% 12% 12% 7%	4466
January	1st to 10th	Night	27% 32% 10% 18% 12% 3	5889
	11th to 20th	Night	42% 30% 13% 11% 4	5900
	21st to end	Night	32% 31% 6% 20% 9% 3	6467
February	1st to 10th	Night	11% 64% 8% 12% 6%	2400
	11th to 20th	Night	9% 61% 3 11% 12% 4	2199
	21st to end	Night	13% 63% 5% 8% 8% 3	1815
March	1st to 10th	Night	23% 34% 9% 15% 16% 2	4918
	11th to 20th	Night	11% 33% 15% 19% 13% 8%	4980
	21st to end	Night	22% 33% 10% 19% 14% 1	5467
April	1st to 10th	Night	8% 63% 6% 15% 8% 1	2200
	11th to 20th	Night	9% 65% 6% 8% 10% 3	2058
	21st to end	Night	8% 63% 7% 13% 8% 1	2000
May	1st to 10th	Night	8% 42% 14% 26% 8% 3	3260
	11th to 20th	Night	13% 44% 16% 21% 5%	3231
	21st to end	Night	12% 46% 13% 23% 6%	3149
June	1st to 10th	Night	15% 69% 9% 6% 1	1710
	11th to 20th	Night	16% 70% 7% 6%	1710
	21st to end	Night	10% 68% 16% 5% 1	1710
July	1st to 10th	Night	18% 42% 26% 14%	2795
	11th to 20th	Night	19% 42% 32% 7%	2786
	21st to end	Night	18% 41% 29% 12%	2988
August	1st to 10th	Night	26% 45% 17% 10% 2	2893
	11th to 20th	Night	18% 42% 22% 18%	3127
	21st to end	Night	21% 48% 27% 3	3690
September	1st to 10th	Night	18% 66% 11% 6%	2090
	11th to 20th	Night	16% 66% 12% 6% 1	2090
	21st to end	Night	17% 66% 7% 7% 3	2090
October	1st to 10th	Night	33% 44% 12% 10% 1	3662
	11th to 20th	Night	32% 41% 10% 9% 7%	3779
	21st to end	Night	21% 40% 9% 20% 9% 2	4120
November	1st to 10th	Night	16% 59% 9% 10% 5% 1	2341
	11th to 20th	Night	20% 59% 5% 9% 5% 2	2400
	21st to end	Night	17% 59% 6% 7% 8% 3	2400
December	1st to 10th	Night	18% 39% 9% 21% 12% 1	3943
	11th to 20th	Night	28% 37% 8% 13% 10% 4	4824
	21st to end	Night	38% 33% 11% 11% 6% 1	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	9% 5% 19% 39% 26% 2	300
	11th to 20th	Day	15% 5% 18% 35% 23% 4	300
	21st to end	Day	10% 5% 24% 44% 17% 1	330
February	1st to 10th	Day	6% 3 14% 37% 34% 5%	300
	11th to 20th	Day	6% 3 15% 39% 30% 6%	437
	21st to end	Day	6% 3 18% 34% 35% 5%	414
March	1st to 10th	Day	4 4 22% 43% 24% 3	500
	11th to 20th	Day	4 5% 16% 40% 31% 3	500
	21st to end	Day	5% 3 17% 39% 30% 5%	550
April	1st to 10th	Day	2 3 13% 52% 26% 4	500
	11th to 20th	Day	6% 2 15% 40% 31% 5%	492
	21st to end	Day	5% 1 8% 35% 45% 5%	500
May	1st to 10th	Day	3 2 7% 31% 47% 10%	503
	11th to 20th	Day	9% 1 8% 29% 39% 13%	527
	21st to end	Day	9% 2 5% 15% 41% 28%	549
June	1st to 10th	Day	12% 2 3 16% 40% 27%	490
	11th to 20th	Day	8% 3 5% 11% 33% 41%	490
	21st to end	Day	3 1 2 5% 30% 58%	490
July	1st to 10th	Day	4 1 2 5% 26% 61%	485
	11th to 20th	Day	5% 2 2 5% 31% 55%	484
	21st to end	Day	3 2 8% 33% 53%	532
August	1st to 10th	Day	6% 2 4 8% 30% 50%	486
	11th to 20th	Day	4 1 2 4 33% 57%	479
	21st to end	Day	8% 1 2 12% 36% 41%	539
September	1st to 10th	Day	8% 2 2 7% 32% 48%	490
	11th to 20th	Day	5% 2 3 9% 33% 48%	490
	21st to end	Day	7% 3 7% 13% 33% 36%	490
October	1st to 10th	Day	10% 4 6% 20% 44% 16%	490
	11th to 20th	Day	11% 4 7% 26% 35% 16%	490
	21st to end	Day	10% 3 13% 23% 39% 12%	539
November	1st to 10th	Day	7% 5% 9% 32% 37% 9%	495
	11th to 20th	Day	11% 4 13% 35% 31% 6%	500
	21st to end	Day	7% 4 15% 35% 36% 3	500
December	1st to 10th	Day	8% 5% 15% 31% 35% 5%	484
	11th to 20th	Day	9% 2 17% 29% 35% 8%	300
	21st to end	Day	11% 5% 18% 30% 28% 9%	330
January	1st to 10th	Night	9% 5% 21% 35% 29% 2	800
	11th to 20th	Night	10% 5% 24% 36% 23% 2	800
	21st to end	Night	10% 5% 24% 41% 19% 1	880
February	1st to 10th	Night	10% 5% 16% 40% 27% 2	800
	11th to 20th	Night	8% 3 22% 37% 29% 2	783
	21st to end	Night	7% 4 16% 44% 27% 1	660
March	1st to 10th	Night	5% 4 25% 42% 22% 2	800
	11th to 20th	Night	6% 4 17% 41% 30% 2	800
	21st to end	Night	6% 4 19% 42% 27% 2	880
April	1st to 10th	Night	5% 2 13% 49% 30% 2	800
	11th to 20th	Night	6% 2 16% 44% 30% 2	791
	21st to end	Night	7% 2 12% 43% 34% 3	800
May	1st to 10th	Night	4 1 7% 42% 40% 5%	800
	11th to 20th	Night	8% 2 10% 38% 38% 5%	789
	21st to end	Night	9% 2 5% 21% 49% 14%	645
June	1st to 10th	Night	12% 2 5% 17% 44% 20%	570
	11th to 20th	Night	8% 2 3 12% 41% 34%	570
	21st to end	Night	5% 1 3 9% 35% 48%	570
July	1st to 10th	Night	5% 1 3 6% 36% 49%	555
	11th to 20th	Night	5% 4 6% 38% 47%	552
	21st to end	Night	3 2 6% 37% 51%	624
August	1st to 10th	Night	8% 1 2 8% 39% 42%	607
	11th to 20th	Night	4 4 5% 40% 47%	750
	21st to end	Night	9% 3 3 11% 39% 36%	836
September	1st to 10th	Night	8% 2 6% 8% 33% 43%	760
	11th to 20th	Night	9% 2 4 10% 37% 38%	760
	21st to end	Night	11% 1 7% 13% 36% 32%	760
October	1st to 10th	Night	12% 3 7% 23% 42% 15%	760
	11th to 20th	Night	11% 4 7% 24% 41% 13%	760
	21st to end	Night	15% 3 11% 29% 31% 10%	836
November	1st to 10th	Night	13% 3 16% 31% 31% 6%	780
	11th to 20th	Night	11% 4 15% 32% 33% 5%	800
	21st to end	Night	11% 3 16% 36% 31% 3	800
December	1st to 10th	Night	8% 5% 16% 34% 33% 4	800
	11th to 20th	Night	12% 4 17% 31% 31% 5%	800
	21st to end	Night	10% 4 19% 33% 30% 4	880

Page generated at 2025-05-23 09:20:58. Version ac07

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