Infrared imagery from NASA’s Aqua satellite revealed that Typhoon Mirinae’s cold thunderstorm clouds were already over sections of the central and northern Philippines on October 30 at 4:53 p.m. (Asia/Manila) local time.

Microwave satellite imagery from NASA’s Aqua satellite showed that Mirinae’s center was close to making a landfall as the storm continued its approach from the east. The Atmospheric Infrared Sounder (AIRS) instrument provided infrared data on Mirinae’s cloud top temperatures, and showed some strong convection and strong thunderstorms with moderate to heavy rainfall over eastern sections of the northern Philippines. The microwave image was created combining AIRS and Advanced Microwave Sounding Unit (AMSU) data. AMSU is another instrument that flies on NASA’s Aqua satellite.

The microwave image revealed cold areas in the storm that indicate ice in cloudtops, and heavy precipitation. Around the eye are the coldest cloud temperatures, as cold as -63F. Microwave data suggests cloud heights to the 200 millibar level, near the tropopause.

Mirinae is also known as “Santi” in the Philippines. Warnings are in effect there are Mirinae (or Santi) is already raining in areas on Friday. Public storm warning signal 3 is in effect in the following districts of Luzon: Quezon, Polillo island, Bulacan, Bataan, Rizal, Cavite, Laguna, Batangas, Oriental Mindoro, Lubang Island, Marinduque, Camarines Norte, Camarines Sur, Catanduanes, Metro Manila; Public storm warning signal 2 is in effect in the following districts of Luzon: Aurora, Quirino, Nueva Ecija, Tarlac, Pampanga, Zambales, Occidental Mindoro, Albay, Burias Island; and Public storm warning signal 1 is in effect in the following districts of Luzon: Isabela, Ifugao, Nueva Vizcaya, Benguet, La Union, Pangasinan, Sorsogon, Masbate, Romblon, Calamian Group. In Visayas, the signal is raised in Northern Samar and Northern Panay.

On October 30 at 5 p.m. local (Asia/Manila) time, or 5 a.m. EDT, Typhoon Mirinae still had maximum sustained winds near 85 knots (97 mph or 157 kph). Typhoon-force winds extend for 30 to 40 miles from the center, while tropical storm-force winds extend as far as 140 miles from the center. Mirinae was centered 205 miles east of Manila, near 14.9 North and 124.6 East.

The Tropical Rainfall Measuring Mission (TRMM) satellite, managed by NASA and JAXA, flew over Mirinae on October 29 and analyzed the rainfall within the storm. The rainfall analysis from the TRMM Microwave Imager and Precipitation Radar instruments showed heavy rainfall of over 30 millimeters (1.18 inches) per hour falling near the typhoon’s center. Typhoon Mirinae has been predicted by the Joint Typhoon Warning Center to pass over the Philippines south of where tropical storm Ketsana traveled in late September. Mirinae is currently predicted to pass within about 44 nautical miles (~81.5 km) to the north of Manila on 31 October 2009. When tropical storm Ketsana moved over the Philippines in late September it produced very heavy rain causing deadly mudslides and flooding in Manila.

Mirinae has weakened as it interacts with the land of the Philippines. The storm will pass over the Philippines and re-emerge into the South China Sea over the weekend.

When Tropical Storm Ketsana moved over the Philippines

in late September it produced very heavy rain causing deadly mudslides and flooding in Manila. This graphic shows the track of Tropical Storm Ketsana in black and the predicted p

Typhoon Mirinae is Already Scaring Philippine Residents Before Halloween

Another typhoon in the northern Philippines really is something to be scared about, and Mirinae is expected to make landfall there in the mid-morning hours on Halloween, October 31. Mirinae will be the fourth major storm to hit the Philippines in one month bringing more rain to an already flood-weary region.

NASA’s Tropical Rainfall Measuring Mission (TRMM) satellite is already hard at work analyzing rainfall, to provide meteorologists with an idea of what can be expected when the storm hits.

NASA and the Japanese Space Agency’s TRMM satellite flew over Typhoon Mirinae on October 29 at 1018 UTC and measured its rainfall from space. Mirinae had moderate rainfall between .78 to 1.57 inches per hour around its center. TRMM images are made at NASA’s Goddard Space Flight Center in Greenbelt, Md. and take some ingenuity to create. A typical TRMM rainfall image combines the infrared and visible channels overlaid with a precipitation analysis from the TRMM Microwave Imager and PR instruments.

The government of the Philippines isn’t waiting for the storm to arrive. It is already sending evacuating people and sending in relief supplies.

On October 29 at 11 a.m. EDT (11 p.m. Asia/Manila Time), Mirinae had maximum sustained winds near 90 knots (104 mph or 167 km/hour). Mirinae’s center was about 480 nautical miles east of Manila, near 15.6 North and 128.7 East. It was still moving west near 12 knots (14 mph) and kicking up dangerous waves as high as 31 feet high.

The environment that Typhoon Mirinie is in is enabling the storm to maintain intensity. Mirinae is in an area of light-to-moderate vertical wind shear. Strong wind shear (winds blowing at different levels of the atmosphere) can tear a storm apart, but that’s not the case in the Philippine Sea where Mirinae is currently located. In addition, the sea surface temperatures remain warm there, in excess of 28 degrees Celsius (82 Fahrenheit). In order for a typhoon or hurricane to maintain intensity, it needs sea surface temperatures as warm as 80F.

Current forecasts expect Mirinae’s center to make landfall sometime around 8 a.m. Asia/Manila time on October 31, and after 12 hours, the storm is expected to move into the South China Sea.