×

Once in a Blue Moon? You mean once every two and a half years. Blue moons are rare occurrences, but are not as rare as people think.

Tonight, the world will experience a “blue moon”, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).

But in this case, the moon doesn’t literally turn blue. The moon is called blue when it’s the second full moon within a month. Usually, there is only one blue moon in a month, with of course, the exception of blue moons.
The lunar cycle is 29 days long, which means that eventually, there will be an appearance of two moons in one month. This usually happens when a full moon appears at the very start of the month, either on the first or second day.

A blue moon happens roughly once every two and a half years on average, the last two happened in August 2012 and July 2015. In rare cases, there are two blue moons in one year. The “double blue moon” occurred last 1999, and will happen again this year – one tonight, and another in March. On the other hand, when double blue moons occur in January and March, February does not have a full moon, partially because it only has 28 days.

Bluer than Blue
There have been cases of an actual “blue moon,” which are rarer than its conventional meaning. The moon changes hue when there are volcanic eruptions or large fires that leave particles in the atmosphere.

One of the longest times a blue moon occurred was when the Indonesian volcano Krakatoa erupted in 1883, equal to the blast of a 100-megaton nuclear bomb. People reported to have heard a cannon-like noise up to 600 kilometers away. Ash and particles about 1 micrometer wide rose up to the Earth’s atmosphere, causing selective light to pass through and reach the surface. The moon “turned blue” for days in areas near Krakatoa.

Reported sightings of a “blue moon” also happened after Mount Pinatubo erupted in 1991. Forest fires are also a cause for blue moons because of the smoke and particles they create. In these occurrences, “lavender suns” are also reported to be seen, also caused by particles in the air.

Historical Mix-up
Originally, the blue moon was considered the third out of four full moons in a season (winter, spring, summer, fall). Each season usually experiences 3 full moons, hence the appearance of a 4th moon, or the Blue Moon, which came rarely and is considered the 13th moon in a year. This was based on Maine Farmer’s Almanac from 1819, which farmers used as reference for agricultural purposes.

However, in 1946, an article on Sky & Telescope misinterpreted the blue moon as the 2nd moon in a month, inferring from the idea that the blue moon appeared as the 13th full moon in a year. The article was titled “Once in a Blue Moon”, a phrase which integrated itself into pop culture meaning something that happens very rarely.
From this misinterpretation, a blue moon can be considered either of the following:
1. It is the extra full moon within a season, which usually has three moons (Maine’s definition); or
2. It is the second full moon within a month (Sky & Telescope’s definition).

The latter is the more popular and commonly used definition for a blue moon nowadays, with the other definition practically defunct.

Illustration from Sky & Telescope

Catch the blue moon tonight, peaking at 8:51 PM (Philippine Standard Time).

SOURCES:
http://www.seasky.org/astronomy/astronomy-glossary.html#B
www.skyandtelescope.com/observing/what-is-a-blue-moon/

PAGASA
NASA

The weather will generally be fair on the last of day of January as the country remains storm-free. However, PAGASA is not dismissing the possibility of possible rains due to the prevailing Northeast Monsoon or Hanging Amihan.

Hanging Amihan, characterized by cold and dry air from Mainland China or Siberia, continues to affect the northern and central parts of Luzon. Cloudy skies with scattered rains will be experienced in the Cordillera Administrative Region (CAR), Cagayan Valley and the province of Aurora.

Meanwhile, Ilocos Region and the rest of Central Luzon can expect partly cloudy to cloudy skies with isolated rains. Metro Manila and the rest of the country will have partly cloudy to cloudy skies with isolated rain showers or thunderstorms.

The surge of Amihan will also cause rough to very rough sea conditions in the northern, eastern and western seaboards of Northern Luzon. Fishing boats and other small seacraft are not allowed to sail as wave height could reach 4.5 meters.

February Overview
With less than 24 hours before we enter the month of February, PAGASA Weather Forecaster shared the weather systems that are expected to prevail. Hanging Amihan will continue to peak, bringing cooler weather and light rains mostly in Luzon.

The Easterlies, Intertropical Convergence Zone (ITCZ), Low Pressure Area (LPA) and Tropical Cyclone are also expected to dump rains and thunderstorms. An average number of 0 to 1 Tropical Cyclone is expected to exist within the Philippine Area of Responsibility (PAR).

Only three days left before the month ends, the country remains storm-free. Despite the absence of a weather disturbance, rains are more likely to prevail due to the Tail-end of a Cold Front and Northeast Monsoon or Hanging Amihan.

The cold front, where cold and warm air masses meet, is composed of rain-producing clouds. In the next hours, Eastern Visayas and Caraga will experience cloudy skies with scattered rain showers or thunderstorms. Residents are advised to prepare for possible flooding in low-lying areas.

Amihan or cold and dry air from the Mainland China or Siberia, is expected bring scattered rains in Cagayan Valley, Cordillera and the rest of Central Luzon. It will also bring isolated rains in Metro Manila, Ilocos Region, Cordillera and the rest of Central Luzon. The remaining parts of the archipelago will have partly cloudy to cloudy skies with isolated rain showers or thunderstorms mostly in the afternoon or evening.


Mayon Ngayon: Albay weather starts to improve

Mayon Volcano has been showing signs of unrest for more than two weeks now. The heavy rains during the weekend brought threats of lahar flows. But compared to the previous days, the weather in Albay is expected to improve starting today.

However, isolated rain showers or thunderstorms may still trigger lahar and sediment-laden flows to the nearby communities. The residents, especially those who are in river channels, are strongly advised to be vigilant.

Two weather systems, including the Tail-end of a Cold Front and Northeast Monsoon or Hanging Amihan, prevail and continue to affect most parts of Luzon. The Tail-end of a Cold Front is the boundary between cold and warm air masses, where convective clouds are formed. On the other hand, Amihan is the cold and dry air coming from Mainland China or Siberia, that usually peaks during the month of January and February.

CALABARZON (Cavite, Laguna, Batangas, Rizal and Quezon), Bicol Region, Eastern Visayas, Mindoro provinces, Marinduque and Aurora will experience cloudy skies with scattered rain showers and thunderstorms. Residents of the said areas, especially Bicol Region, are advised to be alert and keep monitoring updates.

Metro Manila, Cagayan Valley, Cordillera Administrative Region and the rest of Central Luzon will have cloudy skies with scattered rains while chances of isolated rains are expected in Ilocos Region. The rest of the country can expect partly cloudy to cloudy skies with isolated rain showers or thunderstorms.

In an interview with Panahon TV, PAGASA Weather Forecaster Samuel Duran said no weather disturbance is expected to affect the country in the remaining days of the month. However, cloud clusters are observed surrounding the country so all are still advised to monitor further development.

The Northeast Monsoon or Amihan has slightly weakened but continues to blow through extreme Northern Luzon, while the warm and humid Easterlies, dominate the remaining parts of the country.

In the next hours, Eastern Visayas, Central Visayas, Northern Mindanao, Caraga, and Davao Region will have cloudy skies with scattered rain showers and thunderstorms that may trigger flash floods or landslides. In Batanes and the Babuyan Group of Islands, cloudy skies with scattered rains will prevail. The rest of the country, including Metro Manila, can enjoy generally fair weather as partly cloudy to cloudy skies will prevail only with chances of isolated rain showers.

 

Gale warning has been lifted as well, as Amihan weakens. However, colder days are likely to prevail in February as Siberian winds reintensify.

 

 

In today’s interview with PAGASA Weather Forecaster Robert Badrina, he mentioned that no weather disturbance is expected within the next three day.

The Northeast Monsoon affects the extreme Northern Luzon while Easterlies prevail in the remaining parts of the country.

Today, Mindanao, Eastern Visayas, Central Visayas, and Palawan will have cloudy skies with scattered rain showers and thunderstorms; be alert for possible flash floods or landslides. In Batanes and Babuyan Group of Islands, cloudy skies with scattered rains will be experienced. Over the rest of the country including Metro Manila, partly cloudy to cloudy skies, or a generally fair weather will prevail except for chances of isolated rain showers.

Here’s the replay of today’s interview:

Easterlies will continue to affect the country, particularly the eastern section. Despite their warm and humid characteristics, these winds coming from the Pacific Ocean can also bring rains in several parts of the archipelago.

In the next hours, the regions of Cagayan Valley, Bicol, Eastern and Central Visayas, Caraga, Northern Mindanao, Davao and the provinces of Aurora and Quezon will experience cloudy skies with scattered rain showers and thunderstorms. Metro Manila and the rest of the country will have partly cloudy to cloudy skies with isolated rain showers or thunderstorms, mostly in the afternoon or evening.

Compared to the previous days, the effect of Northeast Monsoon or Hanging Amihan has weakened. No gale warning was issued today but coastal waters in the northern and eastern sections of Luzon and the eastern section of Visayas and Mindanao will be moderate to occasionally rough. Elsewhere, slight to moderate sea conditions will prevail.

In an interview with Panahon TV, PAGASA weather forecaster Meno Mendoza said that the country will be storm-free this weekend. No weather disturbance or Tropical Cyclone is expected to enter the Philippine premises in the next 2 to 3 days but the public is still advised to keep monitoring updates from the weather bureau.

The trough or extension of a new weather disturbance is affecting the country. Aside from this, Tail-end of a Cold Front and the Northeast Monsoon are also dominant.

In an interview with Panahon TV, PAGASA Weather Forecaster Meno Mendoza said that the Low Pressure Area (LPA) in Mindanao has dissipated but a new weather disturbance is being monitored outside PAR.

Due to the new LPA’s trough or extension, Visayas and Mindanao will have cloudy skies with scattered rain showers and thunderstorms will make flash floods and landslides possible. For Metro Manila, Central Luzon, CALABARZON, MIMAROPA, and Bicol Region, cloudy skies will be experienced with scattered rain showers and thunderstorms. Over Cagayan Valley Region, residents can expect cloudy skies with scattered rains. In Ilocos Region and Cordillera Administrative Region partly cloudy to cloudy skies can be enjoyed only with isolated rains.

Mayon Volcano in the province of Albay is famous for having a “perfect cone” shape. But it is also known as the country’s most active volcano.

Thirty to forty lava domes are present in the volcano, which constantly release smoke. Due to its persistent threat of eruption, tourist activities such as mountain climbing and ATV driving have been prohibited within the volcano’s 6-kilometer Permanent Danger Zone (PDZ).

Its eruption on February 1, 1814 is considered its most destructive. Around 1,200 died to lahar that buried homes in Cagsawa, Malinao and Mounts Marasaga and Catburauan. This also led to the submerging of the Cagsawa Church, now known as the Cagsawa Ruins. In recent memory, five climbers died due to a sudden spewing of ash and rocks from the volcano last May 7, 2013.

Since Sunday, January 14, 2018, thousands have been evacuated along the path of Mayon Volcano with the threat of its “hazardous eruption”. This came after Phivolcs raised Alert Level 3, warning the possibility of a hazardous eruption. The highest warning, Level 5, means an eruption is ongoing.

Here are photos and videos captured by netizens in Legazpi, Albay:

Mayon Volcano covered with ashes/Ed Barrios, Lagazpi

 

A bright glow from the crater indicates that lava had started to flow/Dante Baclao

Lava flow from Mayon volcano’s summit/Bert Racamunda

11,000 persons were evacuated. As of today, 2,100 packs have been sent to centers in Camalig, and 1,500 packs to Guinobatan

SAFETY TIPS
The Office of Civil Defense released safety measures before, during and after an eruption.

BEFORE
KNOW THE SIGNS OF AN IMPENDING ERUPTION.
– Increase in the frequency of volcanic quakes accompanied by rumbling sounds (no need for periods kasi hindi naman complete sentences)
– Change in color of steam emission from white to gray
– Drying up of vegetation springs and wells around the volcano
– Development of new thermal areas or reactivation of old ones

KNOW THE COMMUNITY’S SAFETY PLANS.
– Always monitor volcano updates and watch out for advisories and warnings
– Know the location of the evacuation site and the fastest and safest way to go there
– Prepare your family’s GO BAG containing items needed for survival

DURING
STAY AWAY FROM DANGER ZONES.
– When notified, immediately evacuate to safer ground
– Assist in evacuating children, pregnant women, PWDs and older people
– Cover your mouth with wet cloth and wear protective goggles
– Keep your pet in their shelter or inside to keep them from inhaling ash
– Stay away from rivers and streams for possible lahar flow

AFTER
REMAIN ALERT AND BE CAUTIOUS.
– Leave the evacuation area only when authorities say it is safe
– Wear a mask when cleaning
– Scrape off the accumulated ash on your roof to prevent its collapse
– Shake loose ash from plants before watering