Hackbart Road Hill
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Hackbart Road Hill clear sky chart from 2005-11-06 to 2024-03-23.

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	15% 11% 5% 8% 7% 4 5% 5% 5% 7% 29%	79247
	Night	15% 11% 5% 9% 7% 4 5% 5% 5% 6% 29%	80612
Transparency	Day	54% 7% 12% 17% 9% 1	78958
	Night	54% 7% 11% 17% 9% 1	80436
Seeing	Day	19% 12% 28% 24% 12% 5%	14040
	Night	19% 11% 30% 28% 11% 1	23195

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% 18% 10% 12% 8% 3 4 4 3 4 20%	2590
	11th to 20th	Day	11% 19% 10% 18% 10% 5% 7% 5% 3 3 8%	2840
	21st to end	Day	21% 19% 9% 13% 8% 4 5% 4 3 4 10%	3124
February	1st to 10th	Day	15% 17% 6% 11% 11% 6% 6% 5% 3 4 15%	1710
	11th to 20th	Day	13% 12% 10% 13% 9% 4 6% 4 5% 7% 17%	1663
	21st to end	Day	16% 15% 7% 10% 9% 4 5% 4 5% 4 21%	1527
March	1st to 10th	Day	14% 13% 5% 10% 8% 4 5% 4 4 5% 27%	2051
	11th to 20th	Day	13% 13% 7% 9% 7% 4 5% 4 4 6% 29%	2090
	21st to end	Day	17% 12% 5% 7% 7% 3 5% 4 4 6% 29%	2200
April	1st to 10th	Day	17% 14% 5% 8% 5% 2 5% 5% 5% 7% 26%	2073
	11th to 20th	Day	19% 10% 3 5% 6% 3 4 4 4 7% 35%	2272
	21st to end	Day	21% 10% 4 7% 5% 3 3 4 5% 6% 31%	2340
May	1st to 10th	Day	17% 9% 4 7% 5% 3 5% 4 5% 9% 32%	2340
	11th to 20th	Day	18% 8% 3 6% 5% 3 4 5% 5% 7% 36%	2368
	21st to end	Day	13% 5% 2 5% 5% 3 5% 5% 7% 9% 40%	2725
June	1st to 10th	Day	14% 6% 3 5% 6% 3 6% 5% 6% 9% 38%	2520
	11th to 20th	Day	12% 6% 2 6% 6% 3 6% 5% 6% 9% 40%	2668
	21st to end	Day	13% 6% 2 5% 6% 3 5% 5% 5% 9% 40%	2700
July	1st to 10th	Day	8% 4 2 5% 5% 3 6% 5% 7% 9% 45%	2700
	11th to 20th	Day	11% 7% 2 5% 6% 5% 5% 5% 7% 9% 37%	2465
	21st to end	Day	10% 6% 3 6% 5% 4 5% 6% 6% 9% 38%	2547
August	1st to 10th	Day	9% 6% 3 6% 6% 4 6% 6% 8% 9% 37%	2327
	11th to 20th	Day	10% 6% 3 6% 7% 4 6% 7% 7% 10% 35%	2303
	21st to end	Day	12% 7% 2 6% 5% 4 5% 6% 6% 8% 38%	2529
September	1st to 10th	Day	12% 6% 3 6% 6% 3 5% 6% 7% 9% 36%	2152
	11th to 20th	Day	11% 6% 2 6% 4 3 5% 6% 6% 8% 41%	1980
	21st to end	Day	16% 7% 3 5% 7% 4 5% 6% 6% 7% 35%	1980
October	1st to 10th	Day	18% 10% 3 7% 6% 4 5% 6% 4 6% 32%	1814
	11th to 20th	Day	21% 11% 4 8% 6% 4 5% 4 5% 7% 26%	1800
	21st to end	Day	24% 13% 5% 7% 6% 3 6% 5% 6% 5% 20%	1962
November	1st to 10th	Day	14% 15% 4 8% 5% 3 5% 4 4 7% 30%	1649
	11th to 20th	Day	15% 15% 5% 9% 8% 3 5% 5% 6% 7% 22%	1520
	21st to end	Day	17% 16% 9% 10% 7% 4 4 5% 5% 6% 17%	1520
December	1st to 10th	Day	14% 20% 9% 14% 9% 5% 4 4 4 4 12%	1520
	11th to 20th	Day	18% 18% 8% 12% 9% 4 6% 5% 4 4 14%	1906
	21st to end	Day	28% 19% 8% 13% 7% 3 4 3 3 3 7%	2772
January	1st to 10th	Night	16% 18% 9% 15% 9% 4 5% 4 4 4 13%	4351
	11th to 20th	Night	13% 14% 8% 15% 13% 6% 6% 6% 6% 4 8%	4120
	21st to end	Night	20% 15% 10% 13% 9% 3 5% 4 4 4 14%	4532
February	1st to 10th	Night	15% 15% 7% 10% 10% 5% 6% 5% 4 5% 17%	2470
	11th to 20th	Night	14% 12% 6% 11% 8% 5% 6% 5% 5% 7% 21%	2403
	21st to end	Night	17% 11% 5% 11% 8% 4 5% 5% 5% 6% 23%	1924
March	1st to 10th	Night	14% 9% 4 9% 7% 4 5% 4 5% 7% 31%	2114
	11th to 20th	Night	13% 10% 6% 7% 7% 4 4 5% 5% 7% 32%	2089
	21st to end	Night	15% 11% 5% 8% 6% 3 4 4 4 5% 35%	2201
April	1st to 10th	Night	19% 9% 4 7% 6% 3 5% 5% 5% 6% 32%	1886
	11th to 20th	Night	16% 9% 4 6% 5% 3 5% 4 5% 7% 36%	1651
	21st to end	Night	15% 10% 4 7% 6% 4 5% 4 5% 7% 34%	1620
May	1st to 10th	Night	16% 8% 3 7% 6% 3 4 5% 5% 8% 38%	1620
	11th to 20th	Night	15% 6% 3 5% 5% 4 5% 5% 4 7% 41%	1522
	21st to end	Night	9% 4 2 4 5% 3 4 4 6% 9% 50%	1550
June	1st to 10th	Night	11% 6% 2 5% 5% 3 5% 5% 5% 7% 45%	1440
	11th to 20th	Night	10% 5% 2 5% 5% 5% 4 5% 6% 10% 43%	1287
	21st to end	Night	11% 5% 2 4 5% 3 4 5% 5% 8% 47%	1260
July	1st to 10th	Night	5% 3 1 4 4 2 4 4 6% 9% 57%	1260
	11th to 20th	Night	8% 4 2 6% 4 2 5% 5% 6% 9% 49%	1486
	21st to end	Night	8% 4 2 5% 6% 3 5% 5% 6% 8% 48%	1771
August	1st to 10th	Night	9% 5% 2 5% 5% 3 4 5% 7% 7% 49%	1611
	11th to 20th	Night	5% 6% 3 5% 6% 2 5% 5% 6% 9% 48%	1598
	21st to end	Night	10% 5% 3 5% 5% 3 5% 5% 6% 7% 46%	1808
September	1st to 10th	Night	10% 6% 3 6% 5% 4 5% 5% 6% 7% 43%	1804
	11th to 20th	Night	10% 5% 3 4 4 3 3 4 5% 7% 51%	1980
	21st to end	Night	15% 7% 2 6% 5% 3 4 4 6% 7% 41%	1980
October	1st to 10th	Night	15% 8% 4 7% 6% 3 4 4 5% 6% 38%	2146
	11th to 20th	Night	19% 10% 3 6% 6% 3 4 5% 5% 7% 31%	2160
	21st to end	Night	23% 10% 4 8% 8% 3 5% 5% 6% 6% 24%	2389
November	1st to 10th	Night	15% 10% 4 7% 6% 3 5% 5% 4 7% 34%	2427
	11th to 20th	Night	16% 12% 5% 9% 7% 4 6% 5% 6% 7% 23%	2660
	21st to end	Night	18% 14% 7% 8% 7% 4 4 5% 5% 7% 21%	2660
December	1st to 10th	Night	18% 17% 9% 12% 7% 4 5% 4 5% 5% 14%	2660
	11th to 20th	Night	14% 19% 7% 13% 7% 4 5% 5% 5% 5% 17%	3288
	21st to end	Night	26% 21% 8% 11% 7% 3 4 3 3 4 8%	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	68% 7% 9% 10% 6%	2591
	11th to 20th	Day	78% 9% 6% 4 3	2840
	21st to end	Day	78% 6% 8% 6% 3	3124
February	1st to 10th	Day	71% 7% 8% 11% 3 1	1710
	11th to 20th	Day	65% 7% 9% 13% 6% 1	1672
	21st to end	Day	64% 6% 12% 12% 6% 1	1527
March	1st to 10th	Day	58% 6% 13% 15% 8% 1	2054
	11th to 20th	Day	55% 7% 10% 16% 10% 2	2090
	21st to end	Day	57% 5% 10% 16% 11% 2	2200
April	1st to 10th	Day	56% 7% 11% 16% 10%	2073
	11th to 20th	Day	49% 6% 12% 20% 12% 1	2272
	21st to end	Day	53% 6% 11% 18% 10% 2	2340
May	1st to 10th	Day	49% 6% 11% 21% 12% 1	2340
	11th to 20th	Day	47% 7% 11% 23% 11% 1	2372
	21st to end	Day	40% 8% 15% 22% 14% 1	2725
June	1st to 10th	Day	42% 8% 14% 21% 15% 1	2520
	11th to 20th	Day	40% 8% 12% 24% 15% 1	2668
	21st to end	Day	41% 7% 13% 24% 14%	2700
July	1st to 10th	Day	33% 9% 15% 24% 18% 2	2626
	11th to 20th	Day	39% 8% 15% 25% 11% 1	2388
	21st to end	Day	39% 9% 14% 23% 14% 2	2405
August	1st to 10th	Day	38% 9% 18% 25% 9% 1	2314
	11th to 20th	Day	42% 9% 17% 22% 10%	2303
	21st to end	Day	42% 8% 13% 25% 11% 1	2529
September	1st to 10th	Day	41% 10% 14% 23% 10% 2	2152
	11th to 20th	Day	37% 8% 14% 28% 12% 1	1980
	21st to end	Day	46% 7% 14% 23% 9% 1	1980
October	1st to 10th	Day	51% 7% 12% 16% 12% 1	1814
	11th to 20th	Day	58% 6% 13% 17% 6%	1800
	21st to end	Day	64% 7% 11% 12% 5%	1962
November	1st to 10th	Day	53% 7% 13% 19% 7% 1	1649
	11th to 20th	Day	58% 8% 14% 12% 7% 1	1520
	21st to end	Day	66% 8% 12% 10% 3	1520
December	1st to 10th	Day	74% 7% 8% 9% 2	1520
	11th to 20th	Day	71% 8% 9% 8% 3	1906
	21st to end	Day	82% 6% 6% 5% 1	2772
January	1st to 10th	Night	72% 8% 8% 8% 3	4351
	11th to 20th	Night	73% 12% 8% 5% 2	4120
	21st to end	Night	72% 7% 9% 8% 3 1	4532
February	1st to 10th	Night	67% 7% 10% 13% 3	2470
	11th to 20th	Night	60% 8% 12% 14% 6%	2405
	21st to end	Night	60% 6% 13% 14% 8%	1924
March	1st to 10th	Night	52% 7% 12% 19% 8% 1	2124
	11th to 20th	Night	50% 6% 12% 19% 10% 2	2090
	21st to end	Night	51% 5% 9% 19% 13% 3	2201
April	1st to 10th	Night	52% 5% 10% 18% 13% 1	1886
	11th to 20th	Night	46% 7% 10% 20% 16% 2	1651
	21st to end	Night	50% 5% 10% 18% 14% 3	1620
May	1st to 10th	Night	45% 6% 10% 21% 15% 2	1620
	11th to 20th	Night	42% 5% 12% 22% 15% 3	1523
	21st to end	Night	31% 7% 16% 27% 17% 4	1551
June	1st to 10th	Night	38% 6% 11% 26% 17% 1	1440
	11th to 20th	Night	36% 7% 13% 25% 17% 3	1287
	21st to end	Night	36% 7% 15% 24% 17% 1	1260
July	1st to 10th	Night	23% 8% 14% 27% 24% 3	1225
	11th to 20th	Night	31% 8% 14% 29% 18% 1	1440
	21st to end	Night	32% 9% 15% 26% 16% 3	1672
August	1st to 10th	Night	33% 8% 17% 30% 12% 2	1600
	11th to 20th	Night	30% 9% 16% 30% 14% 1	1598
	21st to end	Night	34% 8% 13% 29% 14% 1	1808
September	1st to 10th	Night	37% 9% 13% 26% 14% 2	1804
	11th to 20th	Night	32% 6% 13% 30% 18% 1	1980
	21st to end	Night	42% 7% 13% 25% 12%	1980
October	1st to 10th	Night	47% 6% 11% 20% 14% 1	2146
	11th to 20th	Night	52% 7% 14% 19% 8% 1	2160
	21st to end	Night	57% 8% 11% 16% 8%	2389
November	1st to 10th	Night	49% 7% 13% 21% 10% 1	2427
	11th to 20th	Night	57% 9% 12% 14% 6% 1	2660
	21st to end	Night	60% 9% 15% 11% 4 1	2660
December	1st to 10th	Night	71% 8% 11% 8% 2	2660
	11th to 20th	Night	68% 7% 11% 11% 3	3288
	21st to end	Night	80% 6% 8% 5% 1	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	22% 22% 31% 16% 8% 1	202
	11th to 20th	Day	20% 18% 44% 14% 3 1	270
	21st to end	Day	26% 17% 32% 21% 4	297
February	1st to 10th	Day	24% 20% 40% 13% 3	270
	11th to 20th	Day	23% 21% 39% 16% 1	270
	21st to end	Day	28% 28% 29% 13% 1	225
March	1st to 10th	Day	25% 14% 37% 18% 6%	424
	11th to 20th	Day	22% 14% 36% 21% 6% 1	460
	21st to end	Day	26% 15% 34% 19% 6% 1	470
April	1st to 10th	Day	20% 20% 30% 20% 8% 1	420
	11th to 20th	Day	26% 15% 28% 16% 10% 4	412
	21st to end	Day	27% 11% 32% 20% 8% 2	420
May	1st to 10th	Day	22% 12% 27% 24% 11% 4	423
	11th to 20th	Day	21% 9% 28% 23% 14% 6%	447
	21st to end	Day	16% 5% 25% 29% 16% 8%	485
June	1st to 10th	Day	14% 10% 28% 30% 14% 4	450
	11th to 20th	Day	15% 9% 27% 30% 17% 3	598
	21st to end	Day	14% 7% 29% 34% 13% 3	630
July	1st to 10th	Day	7% 6% 25% 29% 23% 10%	621
	11th to 20th	Day	15% 7% 21% 28% 21% 9%	474
	21st to end	Day	11% 3 26% 34% 18% 8%	488
August	1st to 10th	Day	10% 4 20% 29% 24% 14%	446
	11th to 20th	Day	13% 4 18% 29% 21% 15%	439
	21st to end	Day	14% 7% 21% 29% 17% 12%	495
September	1st to 10th	Day	13% 6% 22% 27% 19% 12%	450
	11th to 20th	Day	11% 5% 20% 26% 25% 12%	450
	21st to end	Day	16% 10% 26% 23% 16% 9%	450
October	1st to 10th	Day	21% 12% 25% 21% 14% 7%	450
	11th to 20th	Day	23% 16% 32% 22% 6% 1	450
	21st to end	Day	30% 16% 28% 20% 5% 1	477
November	1st to 10th	Day	20% 23% 28% 19% 8% 1	259
	11th to 20th	Day	24% 18% 32% 20% 4 2	180
	21st to end	Day	23% 18% 39% 17% 3	180
December	1st to 10th	Day	27% 23% 33% 13% 4	180
	11th to 20th	Day	26% 26% 31% 14% 3 1	180
	21st to end	Day	30% 19% 37% 13% 1	198
January	1st to 10th	Night	22% 19% 37% 16% 6% 1	760
	11th to 20th	Night	27% 18% 32% 20% 4	760
	21st to end	Night	20% 11% 39% 25% 6%	836
February	1st to 10th	Night	21% 17% 38% 22% 2	760
	11th to 20th	Night	21% 15% 36% 22% 5%	743
	21st to end	Night	23% 17% 36% 22% 3	628
March	1st to 10th	Night	17% 15% 39% 22% 7%	760
	11th to 20th	Night	17% 18% 36% 22% 6%	760
	21st to end	Night	21% 13% 31% 25% 9% 1	801
April	1st to 10th	Night	23% 14% 31% 27% 5%	720
	11th to 20th	Night	21% 14% 31% 24% 9% 1	587
	21st to end	Night	19% 12% 28% 33% 7% 1	540
May	1st to 10th	Night	17% 6% 32% 30% 13% 1	540
	11th to 20th	Night	20% 4 28% 35% 12% 1	461
	21st to end	Night	11% 3 29% 38% 18%	389
June	1st to 10th	Night	13% 4 29% 40% 14%	360
	11th to 20th	Night	13% 5% 30% 39% 13%	360
	21st to end	Night	14% 3 28% 41% 14%	360
July	1st to 10th	Night	5% 2 18% 52% 22% 1	350
	11th to 20th	Night	9% 4 24% 40% 22% 1	430
	21st to end	Night	9% 2 22% 46% 20% 1	591
August	1st to 10th	Night	10% 2 18% 42% 27% 2	537
	11th to 20th	Night	7% 3 18% 39% 29% 4	534
	21st to end	Night	12% 4 23% 33% 26% 3	620
September	1st to 10th	Night	12% 5% 22% 35% 22% 4	720
	11th to 20th	Night	12% 5% 21% 34% 24% 5%	720
	21st to end	Night	17% 8% 22% 30% 18% 5%	720
October	1st to 10th	Night	20% 8% 26% 28% 16% 2	720
	11th to 20th	Night	22% 13% 28% 28% 8% 2	720
	21st to end	Night	27% 13% 30% 26% 5%	792
November	1st to 10th	Night	21% 11% 28% 29% 9% 1	740
	11th to 20th	Night	22% 14% 35% 20% 7% 1	760
	21st to end	Night	25% 14% 34% 23% 4	760
December	1st to 10th	Night	27% 18% 32% 18% 4	760
	11th to 20th	Night	21% 21% 36% 18% 4	760
	21st to end	Night	29% 17% 34% 18% 3	836

Page generated at 2024-03-19 23:31:04. Version ac07

Copyright © 2024 Attilla Danko.