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.

Typhoon Mirinae is moving west and away from the Northern Marianas Islands on a track to a landfall in the Philippines by the weekend. As Mirinae has moved west, NASA’s infrared and microwave satellite imagery have seen high, strong thunderstorm development, and a developing eye.

Typhoon Mirinae’s maximum sustained winds are now up to 98 mph (157 km/hr), and its center is approximately 930 nautical miles (that’s 1,070 miles or 1,722 kilometers) east of Manila, Philippines. The coordinates of its center are 16.2 North latitude and 136.9 East longitude. Mirinae is moving west at 17 mph.

Tropical storm-force winds extend out to 100 miles from Mirinae’s center, while typhoon/hurricane-force winds extend 20 miles out from its center. Mirinae is stirring up waves up to 22 feet high.

Mirinae is intensifying in part because of “strong radial outflow and warm sea surface temperatures,” according to forecasters at the U.S. Navy’s Joint Typhoon Warning Center (JTWC). JTWC is the organization that forecasts storms in the Western Pacific Ocean. Radial outflow is important in a tropical cyclone development because it spreads ice particles outward from the center of the storm, spreading clouds and precipitation. Basically it helps the storm grow larger.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua satellite captured a microwave and infrared image of Mirinae on October 28 at 12:35 a.m. local Asia/Manila Time.

The infrared imagery revealed that the cloud tops of Mirinae are close to the top of the troposphere. That means they are strong thunderstorms, where temperatures are colder than -63 Fahrenheit.

AIRS data is also coupled with data from the Advanced Microwave Sounding Unit (AMSU) that flies with AIRS on Aqua to create microwave images of storms. The AMSU image uses the radiances of the 89 GHz channel, and the cold areas in those images indicate where there is precipitation or ice in the cloud tops.

Mirinae has intensified steadily and will continue to do so until landfall in the Philippines on Saturday. Landfall in Luzon between the cities of Soliven and San Jose is still expected to occur around 0600 UTC (2 a.m. EDT, 2 p.m. Asia/Manila local time) on Halloween.

It seems like a common occurrence this season that there are two tropical cyclones spinning in the Western Pacific Ocean and this week, Lupit and newly formed 23W are proof. NASA’s Aqua satellite flew over the Western Pacific early today and captured both storms in one satellite image.

Tropical Storm Lupit is becoming extra-tropical and is expected to track parallel to Japan while remaining at sea, east of the island. Meanwhile, Tropical Storm 23W is approaching Saipan and Andersen Air Force Base and is moving west. The U.S. Navy’s Joint Typhoon Warning Center (JTWC) forecasts tropical cyclones in the Western Pacific Ocean. The JWTC issued their final warning for Extra-tropical Storm Lupit today, October 26 at 0300 UTC (12 a.m. local time Tokyo).

At that time, Lupit had maximum sustained winds near 52 mph and was stirring up rough surf and high waves along eastern Japan’s coastline. Extra-tropical storm Lupit was located approximately 580 nautical miles southwest of Tokyo, Japan, near 28.4 North and 134.8 East. It was moving northeast at 21 mph, and is expected to continue moving in that direction staying in open ocean. Lupit was completing transition to an extra-tropical storm and is also being adversely affected by wind shear (winds blowing at the storm in different levels of that atmosphere, that tear the storm apart). NASA’s Aqua satellite flew over both Lupit and TD23W on October 26 at 3:41 UTC (October 25 at 11:41 p.m. EDT).

The Atmospheric Infrared Sounder (AIRS) instrument on Aqua captured both a visible and infrared image of the storms. The infrared satellite image confirmed that all of Lupit’s deep convection (developing strong thunderstorms) has dissipated, and the most intense precipitation has shifted all to the northeast of the center of circulation, further exposing the center to wind shear. Meanwhile, the image also showed that 23W appeared to be getting well-organized.

Tropical Storm 23W had maximum sustained winds near 40 mph at 11 a.m. EDT on October 26. The storm’s center was about 200 nautical miles east of Guam, near 13.4 North and 147.7 East. It was moving west-northwest near 17 mph. NASA’s CloudSat satellite also flew over 23W earlier this morning.

CloudSat captured a side view of 23W’s clouds on Oct. 26 between 03:43 – 03:46 UTC. CloudSat revealed sustained winds of 27 mph and a minimum central pressure of 1002 millibars when it was centered near 122 North and 151.3 East. Sustained winds have since increased to 40 mph. CloudSat also showed some high, strong thunderstorm cloud tops over 14 kilometers (almost 9 miles) high. The forecast track from the JTWC takes Tropical Storm 23W between Andersen Air Force Base (island) and the island of Saipan, located north of Andersen. The storm is then forecast to intensify and move west toward the Philippines.

Two ingredients that don’t mix well with tropical cyclones are waters cooler than 80 degrees Fahrenheit and wind shear. Those two ingredients were added into Tropical Depression Neki’s mix late yesterday, and caused Neki to dissipate.

The Geostationary Operational Environmental Satellite called GOES-11 captured a look at Neki’s remnants this morning, October 27 at 8 a.m. EDT. Neki appeared as an ill-defined, elongated swirl of low clouds. The Central Pacific Hurricane Center (CPHC) noted that Neki “Appears to be just a surface trough in satellite imagery.”

Last night, October 26 at 5 p.m. HST (11 p.m. EDT) the Central Pacific Hurricane Center issued their final advisory on Neki. At that time, Neki was a depression with maximum sustained winds near 35 mph. Neki’s last location was 450 miles north of French Frigate Shoals, or 665 miles north-northwest of Lihue, Hawaii, near 30.3 North and 164.9 West. The depression had a minimum central pressure of 1010 millibars and was speeding north-northeast near 36 mph!

NASA’s Aqua satellite AIRS instrument captured an infrared image of Neki’s clouds on October 26 at 8:35 a.m. EDT. Neki appeared as a round area of clouds on infrared imagery, was devoid of any strong convection.

The CPHC said that “Decreasing sea surface temperatures along [Neki’s northeastern] track and increasing vertical [wind] shear should prevent redevelopment as a tropical cyclone.”