I had never been so interested in (somewhat obsessed with) clear night skies. When I started taking long exposure pictures of the stars in late Jan this year and then enjoyed a stretch of nice nights in Feb till March, I did not know that, over the following months from April to now in August, clear nights were so scarce.
I wish it will get better in September and Oct. How much is the likelihood?
I knew the year-end season will be quite wet -- does it mean we do not expect clear night skies then?
How precious are clear night skies in Singapore?
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Re: How precious are clear night skies in Singapore?
For the climate of Singapore you can refer to this excellent introduction:
http://www.weather.gov.sg/climate-climate-of-singapore/
It does depend on the time of year as the monsoon winds reverse, the inter-tropical convergence zone (ITCZ) migrate north and south of Singapore. In addition you need to factor in the effects of ENSO cycles, or El Nino/La Nina on the climate of Singapore year to year.
Looking at the long-term climatological record, the drier periods are usually from Feb to May, and then Aug to Oct. The more ideal periods will be February and March, as it is the time of year when drier air from Asia is directly overhead Singapore, pushing the equatorial rainband south of the Equator, plus you'll get some cooler nights as well! Sometimes even during the height of the winter monsoon from Dec to Jan, there can be a streak of calm nights after monsoon surges with excellent seeing.
After the northeast monsoon season ends in late March, there is an increased chance of convective storms in afternoons, but there is usually a high pressure system dominating the equatorial region. As such, you can expect about 5-10 clear nights per month, but the duration is shorter with more low clouds rolling in.
Then comes the summer Monsoon season from June to Sep, which is the season of early morning storms called Sumatra Squalls that can occur on about 5 days a month. In my experience the later half of the summer Monsoon season is typically drier with more clear nights, although subject to variations.
Finally as the summer Monsoon transitions into the winter monsoon from Oct, there is a general increase in the rain nights with occasional monsoon surges occuring on average 2 times a month in Dec and Jan. You can look forward to a few clear nights if lucky after Monsoon surges, otherwise the skies are usually overcast even for non-rainy days.
Apart from the monthly variations, there is a quasi regular biweekly oscillation in rainfall anomalies known as the Madden Julien Oscillation (MJO) that typically brings two weeks of wetter conditions followed by two weeks of drier conditions to Singapore. However, the MJO is highly variable within the year and sometimes has little to no activities at all. You may refer to the following site for more information:
https://www.cpc.ncep.noaa.gov/products/ ... /mjo.shtml
For year to year variations, look up on El Nino/La Nina updates. In a nutshell, El Nino brings drier and warmer conditions to Singapore and vice versa. The latest ENSO update is given here:
https://www.cpc.ncep.noaa.gov/products/ ... enso.shtml
The above is good for long term planning purposes, but if you need to decide whether or not to go out at 11 pm on a weekday for a session, I recommend downloading an app called "Windy", where you can see the real-time satellite images of the globe and zoom in on Singapore. You can judge by the animation the direction in which clouds are moving and then decide if you want to set up or call it a night.
Best of luck on your astrophotography journey!
http://www.weather.gov.sg/climate-climate-of-singapore/
It does depend on the time of year as the monsoon winds reverse, the inter-tropical convergence zone (ITCZ) migrate north and south of Singapore. In addition you need to factor in the effects of ENSO cycles, or El Nino/La Nina on the climate of Singapore year to year.
Looking at the long-term climatological record, the drier periods are usually from Feb to May, and then Aug to Oct. The more ideal periods will be February and March, as it is the time of year when drier air from Asia is directly overhead Singapore, pushing the equatorial rainband south of the Equator, plus you'll get some cooler nights as well! Sometimes even during the height of the winter monsoon from Dec to Jan, there can be a streak of calm nights after monsoon surges with excellent seeing.
After the northeast monsoon season ends in late March, there is an increased chance of convective storms in afternoons, but there is usually a high pressure system dominating the equatorial region. As such, you can expect about 5-10 clear nights per month, but the duration is shorter with more low clouds rolling in.
Then comes the summer Monsoon season from June to Sep, which is the season of early morning storms called Sumatra Squalls that can occur on about 5 days a month. In my experience the later half of the summer Monsoon season is typically drier with more clear nights, although subject to variations.
Finally as the summer Monsoon transitions into the winter monsoon from Oct, there is a general increase in the rain nights with occasional monsoon surges occuring on average 2 times a month in Dec and Jan. You can look forward to a few clear nights if lucky after Monsoon surges, otherwise the skies are usually overcast even for non-rainy days.
Apart from the monthly variations, there is a quasi regular biweekly oscillation in rainfall anomalies known as the Madden Julien Oscillation (MJO) that typically brings two weeks of wetter conditions followed by two weeks of drier conditions to Singapore. However, the MJO is highly variable within the year and sometimes has little to no activities at all. You may refer to the following site for more information:
https://www.cpc.ncep.noaa.gov/products/ ... /mjo.shtml
For year to year variations, look up on El Nino/La Nina updates. In a nutshell, El Nino brings drier and warmer conditions to Singapore and vice versa. The latest ENSO update is given here:
https://www.cpc.ncep.noaa.gov/products/ ... enso.shtml
The above is good for long term planning purposes, but if you need to decide whether or not to go out at 11 pm on a weekday for a session, I recommend downloading an app called "Windy", where you can see the real-time satellite images of the globe and zoom in on Singapore. You can judge by the animation the direction in which clouds are moving and then decide if you want to set up or call it a night.
Best of luck on your astrophotography journey!
Re: How precious are clear night skies in Singapore?
Super informative! Thanks a million.. Yes I have been using Windy for a while.rifleman175 wrote: ↑Sat Aug 15, 2020 2:44 pm For the climate of Singapore you can refer to this excellent introduction:
http://www.weather.gov.sg/climate-climate-of-singapore/
It does depend on the time of year as the monsoon winds reverse, the inter-tropical convergence zone (ITCZ) migrate north and south of Singapore. In addition you need to factor in the effects of ENSO cycles, or El Nino/La Nina on the climate of Singapore year to year.
Looking at the long-term climatological record, the drier periods are usually from Feb to May, and then Aug to Oct. The more ideal periods will be February and March, as it is the time of year when drier air from Asia is directly overhead Singapore, pushing the equatorial rainband south of the Equator, plus you'll get some cooler nights as well! Sometimes even during the height of the winter monsoon from Dec to Jan, there can be a streak of calm nights after monsoon surges with excellent seeing.
After the northeast monsoon season ends in late March, there is an increased chance of convective storms in afternoons, but there is usually a high pressure system dominating the equatorial region. As such, you can expect about 5-10 clear nights per month, but the duration is shorter with more low clouds rolling in.
Then comes the summer Monsoon season from June to Sep, which is the season of early morning storms called Sumatra Squalls that can occur on about 5 days a month. In my experience the later half of the summer Monsoon season is typically drier with more clear nights, although subject to variations.
Finally as the summer Monsoon transitions into the winter monsoon from Oct, there is a general increase in the rain nights with occasional monsoon surges occuring on average 2 times a month in Dec and Jan. You can look forward to a few clear nights if lucky after Monsoon surges, otherwise the skies are usually overcast even for non-rainy days.
Apart from the monthly variations, there is a quasi regular biweekly oscillation in rainfall anomalies known as the Madden Julien Oscillation (MJO) that typically brings two weeks of wetter conditions followed by two weeks of drier conditions to Singapore. However, the MJO is highly variable within the year and sometimes has little to no activities at all. You may refer to the following site for more information:
https://www.cpc.ncep.noaa.gov/products/ ... /mjo.shtml
For year to year variations, look up on El Nino/La Nina updates. In a nutshell, El Nino brings drier and warmer conditions to Singapore and vice versa. The latest ENSO update is given here:
https://www.cpc.ncep.noaa.gov/products/ ... enso.shtml
The above is good for long term planning purposes, but if you need to decide whether or not to go out at 11 pm on a weekday for a session, I recommend downloading an app called "Windy", where you can see the real-time satellite images of the globe and zoom in on Singapore. You can judge by the animation the direction in which clouds are moving and then decide if you want to set up or call it a night.
Best of luck on your astrophotography journey!