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Here’s Looking @ Earth… Weather Nasties—Hilary + Nesat (Imagery)

[SatNews] One hurricane and one typhoon are aiming for landfall…


This visible image of Hurricane Hilary was captured by the MODIS instrument on Saturday, Sept. 24 at 17:40 UTC (1:40 p.m. EDT) when it was off the west coast of Mexico. Credit: NASA Goddard MODIS Rapid Response Team
Text credit: Rob Gutro, NASA’s Goddard Space Flight Center, Greenbelt, Md.
Hurricane Hilary pulled away from the western Mexico coastline this weekend, and NASA‘s TRMM satellite has monitored its rainfall. Hilary’s heaviest rainfall is in its northwest quadrant, and falling over open ocean today, but Hilary may be headed back toward land. NASA’s Tropical Rainfall Measuring Mission satellite known as TRMM passed over Hilary on Sept. 26 at 5:29 a.m. EDT and its precipitation radar instrument measured rainfall happening throughout the storm from its orbit in space. TRMM saw that most of the rainfall occurring in Hurricane Hilary today was moderate, and the heaviest area was limited to its northwestern quadrant where rain was coming down at 2 inches/50 mm per hour. TRMM also has the ability to measure cloud heights, which indicate the power within a hurricane. The higher the towering clouds around the eye, usually the stronger the power within the hurricane. TRMM noticed that the highest cumulonimbus (thunderstorm) clouds in the center were around 14 kilometers (8.6 miles). Towering clouds that height are indicative of a lot of power in the storm.

At 5:00 a.m. EDT (2:00 a.m. PDT) on Sept. 26, Hilary’s maximum sustained winds were near 120 mph (195 kmh). It was centered near 16.9 North and 112.2 West, about 440 miles (710 km) south-southwest of the southern tip of Baja California. It is moving away from Mexico to the west at 10 mph (17 kmh) and has a minimum central pressure of 959 millibars. Hilary is going through some changes today. It appears slightly elongated today from north to south. Cloud top temperatures in infrared satellite imagery indicate that her cloud tops are cooling, indicating they’re going higher (and getting stronger). The National Hurricane Center forecast calls for Hilary to change course and take a northeastern track, coming close to Baja California by the end of the week, but as a depression. Forecasters and NASA satellites are keeping a close eye on Hilary this week.


This visible image of Typhoon Nesat was captured by the MODIS instrument on Sunday, Sept. 25 at 2:40 UTC as its western edges began to spread over the Philippines. Nesat’s eye is not visible in this image. Credit: NASA Goddard MODIS Rapid Response Team
Text credit: Rob Gutro NASA/Goddard Space Flight Center, Greenbelt, Md.
NASA’s Terra satellitea saw the western edges of Typhoon Nesat brushing the eastern Philippines yesterday as Luzon prepares for a landfall today. Warning Signals are in effect throughout the northern Philippines as the typhoon nears. NASA’s Terra satellite flew over Typhoon Nesat yesterday. Nesat is known locally in the Philippines as “Pedring.” NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) captured a visible image of the large storm on Sunday, Sept. 25 at 2:40 UTC (10:40 a.m. local time/Philippines) as its western edges began to spread over the Philippines. Although the visible image did not reveal an eye because it was cloud-filled, satellite microwave imagery did spot the eye. Typhoon Nesat has maximum sustained winds near 80 knots (92 mph/148 kmh) on Monday, Sept. 26 as its center approaches northern Luzon, Philippines. It was located only 225 miles east-northwest of Manila, near 15.9 North and 124.2 East. It was moving to the west-northwest near 14 knots (16 mph/26 kmh).

Satellite imagery shows tightly-curved bands of thunderstorms wrapping into the low level center of circulation. That’s an indication the storm is well-organized. The strongest convection and thunderstorms are mostly over the western semi-circle of the storm today. Microwave satellite data does reveal Nesat has an eye which helps forecasters pinpoint Nesat’s center. PAGASA, the Philippines’ meteorological service expects Nesat (Pedring) will make landfall Tuesday afternoon (local time/Philippines) over Casiguran, Aurora and will be in the vicinity of Baguio City. Coastal areas can expect dangerous surf and high ocean swells, heavy rainfall and gusty winds. Many watches and warnings are in effect. A Signal 3 (for the strongest winds) has been posted for many locales. The Joint Typhoon Warning Center forecasts Nesat to continue tracking due west over Luzon and make landfall with maximum sustained winds near 90 knots (103 mph/166 kmh). It is forecast to cross Luzon and move into the South China Sea in one day.