Withlacoochee River Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Withlacoochee River Park clear sky chart from 2005-11-06 to 2024-04-25.

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	9% 5% 3 6% 7% 4 6% 6% 6% 9% 39%	83769
	Night	10% 5% 3 6% 6% 3 5% 5% 6% 9% 43%	85343
Transparency	Day	41% 9% 14% 18% 13% 6%	83492
	Night	37% 9% 15% 19% 14% 5%	85139
Seeing	Day	9% 6% 19% 25% 23% 17%	14722
	Night	9% 5% 21% 33% 24% 8%	24880

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	11% 8% 2 5% 5% 3 5% 5% 5% 8% 42%	2836
	11th to 20th	Day	21% 9% 3 6% 4 3 4 4 4 7% 35%	2840
	21st to end	Day	11% 6% 2 5% 5% 3 4 5% 5% 8% 46%	3316
February	1st to 10th	Day	12% 5% 3 5% 4 3 4 5% 5% 9% 44%	1900
	11th to 20th	Day	9% 3 3 5% 4 2 4 4 6% 6% 54%	1848
	21st to end	Day	8% 4 2 5% 5% 4 4 4 5% 6% 51%	1638
March	1st to 10th	Day	8% 6% 3 8% 6% 4 6% 6% 6% 8% 40%	3435
	11th to 20th	Day	7% 4 2 5% 5% 2 4 5% 7% 10% 50%	3480
	21st to end	Day	10% 4 2 5% 4 3 3 4 5% 7% 51%	3815
April	1st to 10th	Day	7% 3 1 4 5% 4 5% 5% 7% 7% 50%	2090
	11th to 20th	Day	7% 4 3 5% 6% 4 6% 5% 6% 9% 45%	2066
	21st to end	Day	5% 3 1 4 5% 4 5% 5% 7% 9% 52%	2211
May	1st to 10th	Day	4 3 1 4 4 4 5% 5% 5% 8% 56%	2340
	11th to 20th	Day	9% 4 3 6% 8% 5% 6% 5% 6% 9% 41%	2301
	21st to end	Day	7% 4 3 6% 8% 5% 7% 7% 7% 8% 37%	2531
June	1st to 10th	Day	14% 7% 3 9% 8% 5% 8% 7% 7% 9% 24%	2340
	11th to 20th	Day	6% 5% 3 9% 8% 6% 9% 8% 8% 11% 26%	2340
	21st to end	Day	8% 6% 3 9% 9% 5% 8% 8% 8% 10% 26%	2340
July	1st to 10th	Day	10% 5% 3 8% 10% 6% 9% 10% 8% 9% 23%	2340
	11th to 20th	Day	7% 6% 4 10% 10% 5% 8% 9% 8% 10% 23%	2340
	21st to end	Day	8% 5% 3 9% 10% 6% 9% 9% 8% 11% 22%	2547
August	1st to 10th	Day	7% 6% 3 8% 9% 6% 8% 8% 9% 11% 25%	2327
	11th to 20th	Day	8% 6% 3 8% 9% 7% 8% 8% 9% 11% 23%	2154
	21st to end	Day	10% 7% 4 9% 10% 5% 7% 7% 8% 11% 23%	2178
September	1st to 10th	Day	8% 6% 3 8% 9% 7% 8% 9% 8% 10% 24%	1980
	11th to 20th	Day	10% 7% 3 8% 8% 6% 8% 6% 8% 10% 25%	1980
	21st to end	Day	9% 5% 3 9% 7% 6% 6% 8% 7% 9% 31%	1980
October	1st to 10th	Day	10% 5% 3 7% 7% 4 6% 7% 6% 8% 36%	1980
	11th to 20th	Day	7% 3 2 4 6% 4 5% 5% 7% 8% 48%	1814
	21st to end	Day	8% 4 2 5% 4 3 4 5% 6% 9% 49%	1980
November	1st to 10th	Day	9% 4 2 5% 5% 3 5% 4 5% 7% 51%	1857
	11th to 20th	Day	9% 6% 2 6% 6% 3 4 5% 6% 6% 47%	1900
	21st to end	Day	9% 5% 2 6% 5% 3 4 4 7% 9% 45%	1758
December	1st to 10th	Day	7% 4 2 5% 6% 3 5% 4 6% 9% 48%	1710
	11th to 20th	Day	12% 6% 3 6% 5% 3 4 5% 5% 8% 44%	2153
	21st to end	Day	13% 7% 3 7% 7% 4 5% 5% 5% 6% 37%	3124
January	1st to 10th	Night	12% 7% 3 7% 6% 3 5% 5% 5% 7% 40%	4109
	11th to 20th	Night	19% 9% 3 7% 6% 3 4 4 5% 8% 32%	4120
	21st to end	Night	13% 6% 3 5% 6% 3 5% 6% 5% 8% 40%	4336
February	1st to 10th	Night	11% 6% 2 4 4 2 4 5% 6% 8% 46%	2280
	11th to 20th	Night	11% 4 2 4 5% 3 5% 4 5% 8% 51%	2218
	21st to end	Night	7% 6% 2 6% 6% 2 4 4 5% 7% 50%	1813
March	1st to 10th	Night	16% 8% 3 7% 6% 4 5% 4 5% 6% 37%	3418
	11th to 20th	Night	6% 4 2 4 5% 2 4 5% 8% 12% 48%	3480
	21st to end	Night	11% 5% 2 4 5% 3 3 4 5% 7% 51%	3817
April	1st to 10th	Night	7% 3 2 4 4 3 5% 5% 6% 10% 52%	2090
	11th to 20th	Night	8% 4 2 4 5% 3 4 5% 6% 10% 50%	2063
	21st to end	Night	6% 3 1 4 4 3 5% 4 5% 7% 58%	1855
May	1st to 10th	Night	5% 2 1 3 3 3 4 4 4 9% 62%	1626
	11th to 20th	Night	5% 5% 2 5% 6% 4 4 6% 7% 9% 48%	1592
	21st to end	Night	6% 4 2 5% 6% 4 5% 5% 6% 10% 49%	1744
June	1st to 10th	Night	11% 6% 3 5% 6% 4 6% 7% 7% 9% 36%	1620
	11th to 20th	Night	6% 4 3 5% 6% 3 6% 8% 8% 14% 37%	1620
	21st to end	Night	8% 5% 3 6% 7% 4 6% 8% 9% 12% 32%	1620
July	1st to 10th	Night	8% 5% 3 6% 6% 4 8% 7% 9% 11% 32%	1620
	11th to 20th	Night	6% 4 3 7% 7% 5% 8% 9% 10% 12% 30%	1620
	21st to end	Night	4 4 3 6% 9% 5% 7% 8% 10% 13% 30%	1771
August	1st to 10th	Night	4 5% 3 8% 7% 5% 6% 7% 8% 14% 33%	1611
	11th to 20th	Night	5% 5% 3 6% 6% 4 8% 7% 9% 14% 32%	1724
	21st to end	Night	9% 7% 3 7% 7% 5% 5% 7% 8% 11% 30%	2174
September	1st to 10th	Night	7% 5% 3 6% 8% 5% 6% 8% 9% 13% 30%	1980
	11th to 20th	Night	10% 7% 3 8% 7% 5% 6% 6% 8% 11% 30%	1980
	21st to end	Night	10% 6% 4 7% 7% 4 5% 6% 7% 8% 36%	1980
October	1st to 10th	Night	9% 6% 2 5% 6% 3 6% 6% 7% 8% 41%	1980
	11th to 20th	Night	7% 4 2 4 4 3 5% 4 6% 9% 52%	2144
	21st to end	Night	9% 4 3 6% 5% 3 4 4 5% 7% 51%	2376
November	1st to 10th	Night	9% 3 2 4 5% 3 5% 4 5% 7% 54%	2221
	11th to 20th	Night	9% 5% 2 5% 5% 3 4 5% 4 6% 50%	2280
	21st to end	Night	9% 5% 2 6% 6% 4 4 5% 4 8% 47%	2417
December	1st to 10th	Night	8% 3 2 5% 5% 3 4 5% 5% 8% 50%	2470
	11th to 20th	Night	13% 6% 3 5% 4 2 4 4 4 7% 48%	3042
	21st to end	Night	15% 7% 3 6% 6% 3 5% 5% 5% 8% 37%	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	40% 6% 8% 18% 19% 9%	2837
	11th to 20th	Day	50% 4 5% 17% 16% 9%	2840
	21st to end	Day	36% 6% 8% 19% 22% 8%	3316
February	1st to 10th	Day	38% 6% 9% 17% 19% 12%	1900
	11th to 20th	Day	30% 6% 8% 18% 25% 12%	1858
	21st to end	Day	34% 5% 11% 17% 22% 12%	1638
March	1st to 10th	Day	40% 10% 12% 18% 14% 6%	3435
	11th to 20th	Day	28% 6% 12% 28% 20% 6%	3480
	21st to end	Day	31% 5% 9% 29% 17% 8%	3815
April	1st to 10th	Day	30% 7% 14% 23% 17% 9%	2090
	11th to 20th	Day	36% 7% 12% 18% 21% 7%	2066
	21st to end	Day	28% 7% 11% 22% 24% 8%	2211
May	1st to 10th	Day	25% 7% 12% 22% 23% 10%	2340
	11th to 20th	Day	39% 9% 14% 20% 14% 3	2305
	21st to end	Day	42% 8% 13% 18% 15% 2	2531
June	1st to 10th	Day	54% 11% 15% 14% 4	2340
	11th to 20th	Day	48% 13% 20% 17% 2	2340
	21st to end	Day	51% 12% 20% 13% 3 1	2340
July	1st to 10th	Day	53% 15% 22% 8% 1	2275
	11th to 20th	Day	52% 17% 21% 9%	2271
	21st to end	Day	50% 16% 22% 11% 1	2405
August	1st to 10th	Day	47% 16% 27% 10%	2314
	11th to 20th	Day	49% 18% 22% 10% 1	2154
	21st to end	Day	52% 15% 20% 11% 2	2178
September	1st to 10th	Day	51% 16% 19% 11% 3	1980
	11th to 20th	Day	51% 13% 20% 12% 4	1980
	21st to end	Day	47% 11% 14% 15% 10% 3	1980
October	1st to 10th	Day	44% 9% 12% 15% 12% 8%	1980
	11th to 20th	Day	33% 6% 11% 22% 21% 6%	1814
	21st to end	Day	31% 7% 12% 18% 21% 12%	1980
November	1st to 10th	Day	33% 6% 10% 20% 19% 12%	1857
	11th to 20th	Day	36% 6% 9% 19% 20% 9%	1900
	21st to end	Day	36% 6% 10% 22% 19% 7%	1758
December	1st to 10th	Day	32% 6% 14% 25% 16% 6%	1710
	11th to 20th	Day	39% 5% 10% 17% 17% 12%	2150
	21st to end	Day	45% 7% 10% 18% 14% 5%	3124
January	1st to 10th	Night	43% 6% 9% 15% 20% 7%	4109
	11th to 20th	Night	50% 5% 8% 18% 13% 5%	4120
	21st to end	Night	40% 8% 11% 16% 17% 9%	4336
February	1st to 10th	Night	34% 7% 11% 18% 19% 11%	2280
	11th to 20th	Night	31% 6% 10% 20% 23% 10%	2219
	21st to end	Night	33% 6% 12% 19% 23% 8%	1813
March	1st to 10th	Night	46% 9% 11% 16% 14% 5%	3418
	11th to 20th	Night	25% 8% 22% 25% 14% 5%	3480
	21st to end	Night	32% 7% 9% 26% 20% 6%	3817
April	1st to 10th	Night	27% 7% 19% 24% 16% 7%	2090
	11th to 20th	Night	29% 8% 15% 24% 19% 6%	2063
	21st to end	Night	25% 6% 15% 24% 24% 7%	1855
May	1st to 10th	Night	21% 7% 14% 27% 23% 9%	1626
	11th to 20th	Night	30% 10% 22% 21% 15% 1	1593
	21st to end	Night	30% 10% 16% 23% 18% 2	1745
June	1st to 10th	Night	41% 13% 20% 20% 6%	1620
	11th to 20th	Night	35% 12% 30% 21% 3	1620
	21st to end	Night	41% 16% 23% 14% 5%	1620
July	1st to 10th	Night	42% 19% 28% 9% 2	1575
	11th to 20th	Night	43% 19% 29% 8% 1	1566
	21st to end	Night	38% 22% 28% 10% 1	1672
August	1st to 10th	Night	37% 18% 34% 11% 1	1600
	11th to 20th	Night	38% 19% 31% 12% 1	1724
	21st to end	Night	45% 17% 22% 14% 2	2174
September	1st to 10th	Night	42% 19% 23% 12% 4	1980
	11th to 20th	Night	46% 15% 19% 16% 3 1	1980
	21st to end	Night	43% 11% 17% 17% 9% 3	1980
October	1st to 10th	Night	37% 11% 13% 18% 14% 7%	1980
	11th to 20th	Night	28% 7% 13% 25% 22% 5%	2144
	21st to end	Night	32% 7% 10% 19% 22% 10%	2376
November	1st to 10th	Night	30% 6% 14% 20% 20% 11%	2221
	11th to 20th	Night	35% 7% 9% 20% 20% 9%	2280
	21st to end	Night	36% 6% 9% 22% 19% 8%	2417
December	1st to 10th	Night	31% 6% 14% 27% 15% 6%	2470
	11th to 20th	Night	36% 6% 9% 20% 17% 12%	3044
	21st to end	Night	45% 7% 12% 18% 14% 4	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	10% 15% 42% 24% 8%	270
	11th to 20th	Day	7% 16% 36% 28% 10% 2	270
	21st to end	Day	13% 20% 46% 16% 5% 1	297
February	1st to 10th	Day	14% 13% 34% 24% 13% 1	270
	11th to 20th	Day	13% 9% 38% 26% 10% 5%	270
	21st to end	Day	9% 12% 30% 33% 15% 1	293
March	1st to 10th	Day	5% 15% 37% 29% 13% 1	460
	11th to 20th	Day	11% 9% 29% 31% 17% 3	460
	21st to end	Day	7% 11% 29% 32% 19% 2	506
April	1st to 10th	Day	9% 10% 30% 29% 18% 3	460
	11th to 20th	Day	9% 10% 27% 30% 20% 4	452
	21st to end	Day	5% 5% 25% 30% 25% 8%	437
May	1st to 10th	Day	6% 5% 20% 34% 25% 11%	423
	11th to 20th	Day	11% 2 15% 29% 27% 16%	447
	21st to end	Day	7% 3 11% 19% 36% 24%	485
June	1st to 10th	Day	14% 3 10% 23% 28% 23%	450
	11th to 20th	Day	8% 2 7% 23% 27% 33%	450
	21st to end	Day	6% 1 6% 15% 28% 45%	450
July	1st to 10th	Day	8% 1 5% 12% 26% 48%	445
	11th to 20th	Day	6% 1 4 11% 33% 45%	444
	21st to end	Day	6% 2 7% 18% 27% 40%	488
August	1st to 10th	Day	8% 1 4 13% 33% 41%	446
	11th to 20th	Day	8% 1 3 11% 30% 46%	439
	21st to end	Day	9% 2 6% 22% 28% 33%	495
September	1st to 10th	Day	7% 2 7% 16% 32% 38%	450
	11th to 20th	Day	10% 3 7% 21% 31% 28%	450
	21st to end	Day	9% 3 8% 22% 33% 26%	450
October	1st to 10th	Day	10% 6% 21% 31% 23% 8%	450
	11th to 20th	Day	6% 6% 15% 36% 28% 9%	450
	21st to end	Day	8% 5% 20% 35% 28% 4	495
November	1st to 10th	Day	9% 6% 23% 31% 25% 6%	455
	11th to 20th	Day	13% 7% 24% 35% 17% 4	460
	21st to end	Day	11% 7% 33% 31% 15% 2	318
December	1st to 10th	Day	6% 11% 33% 29% 17% 4	270
	11th to 20th	Day	13% 10% 32% 31% 11% 2	270
	21st to end	Day	9% 12% 30% 35% 12% 2	297
January	1st to 10th	Night	11% 11% 33% 33% 11%	760
	11th to 20th	Night	13% 9% 26% 39% 13% 1	760
	21st to end	Night	13% 10% 37% 32% 7%	836
February	1st to 10th	Night	15% 7% 31% 34% 12%	760
	11th to 20th	Night	10% 8% 30% 39% 12% 1	743
	21st to end	Night	9% 8% 34% 41% 9%	628
March	1st to 10th	Night	7% 9% 37% 38% 10%	760
	11th to 20th	Night	9% 8% 31% 39% 13% 1	760
	21st to end	Night	8% 7% 34% 39% 12%	836
April	1st to 10th	Night	8% 8% 32% 40% 13%	760
	11th to 20th	Night	8% 8% 32% 38% 13% 1	751
	21st to end	Night	6% 5% 26% 43% 19% 1	740
May	1st to 10th	Night	6% 3 17% 47% 24% 3	546
	11th to 20th	Night	5% 2 18% 42% 29% 4	531
	21st to end	Night	5% 1 12% 35% 40% 7%	584
June	1st to 10th	Night	13% 1 9% 29% 37% 10%	540
	11th to 20th	Night	6% 1 6% 22% 41% 23%	540
	21st to end	Night	9% 2 3 15% 43% 28%	540
July	1st to 10th	Night	8% 1 3 14% 44% 31%	525
	11th to 20th	Night	4 1 2 12% 48% 33%	522
	21st to end	Night	5% 2 14% 47% 31%	591
August	1st to 10th	Night	3 1 3 12% 52% 29%	537
	11th to 20th	Night	6% 1 4 8% 45% 37%	534
	21st to end	Night	12% 2 7% 20% 39% 20%	788
September	1st to 10th	Night	8% 2 7% 23% 42% 19%	720
	11th to 20th	Night	13% 2 8% 28% 36% 14%	720
	21st to end	Night	11% 3 11% 29% 38% 9%	720
October	1st to 10th	Night	12% 3 19% 39% 23% 4	720
	11th to 20th	Night	7% 4 17% 39% 31% 3	720
	21st to end	Night	9% 5% 20% 39% 25% 2	792
November	1st to 10th	Night	9% 4 27% 35% 21% 3	740
	11th to 20th	Night	10% 7% 23% 42% 16% 1	760
	21st to end	Night	11% 5% 30% 39% 15% 1	760
December	1st to 10th	Night	8% 6% 28% 37% 21% 1	760
	11th to 20th	Night	10% 8% 29% 35% 18% 1	760
	21st to end	Night	11% 7% 28% 38% 15% 1	836

Page generated at 2024-04-22 09:25:40. Version ac07

Copyright © 2024 Attilla Danko.