Extreme Weather

The GPM core observatory satellite had an excellent view of tropical storm MALIKSI when it passed over southern Japan on June 10, 2018 at 1759 UTC. GPM's Microwave Imager (GMI) and Dual Frequency Precipitation Radar (DPR) instruments collected data that revealed the horizontal and vertical extent of precipitation within the tropical storm. GPM's GMI showed that heavy downpours were occurring in a rain band wrapping around MALIKSI's northeastern side. GPM's radar (DPR Ku Band) found that bands of storms moving around the northwestern side of the tropical storm were dropping rain at a rate of

As expected, tropical storm Aletta intensified and became a hurricane. Aletta was a powerful hurricane with winds of about 85 kts (98 mph) when the GPM core observatory satellite passed over head on June 7, 2018 at 18:38 PM MDT (June 8, 2018 at 0038 UTC). GPM's Microwave Imager (GMI) and Dual Frequency Precipitation Radar (DPR) instruments showed that hurricane Aletta contained powerful storms that were producing heavy precipitation. Very strong convective storms were producing heavy rainfall in Aletta's eye wall while the most extreme downpours were shown in a large feeder band wrapping

Early today Tropical Depression Two-E was upgraded to tropical storm Aletta. This is the first tropical storm of the 2018 eastern North Pacific season. Aletta was located well southwest of Mexico. The National Hurricane Center (NHC) predicts that Aletta will become a hurricane tomorrow as it moves westward over the open waters of the eastern North Pacific ocean. The GPM core observatory satellite passed above developing tropical storm Aletta on June 6, 2018 at 0046 UTC. This image shows precipitation measurements that were calculated from data collected by GPM's Microwave Imager (GMI) and Dual

The first cyclone to strike the area, Sagar, formed from an area of thunderstorm activity located in the western Arabian Sea south of the island of Socatra. The area of low pressure associated with the thunderstorms first moved northwest into the far eastern Gulf of Aden, where it intensified into a minimal tropical storm with sustained winds estimated at 35 knots (~40 mph) by the Joint Typhoon Warning Center (JTWC), before turning west and then southwest down the middle of the Gulf. As it moved down the Gulf, Sagar slowly strengthened into a stronger tropical storm with sustained winds

Alberto formed out of a broad area of low pressure at the surface that was located over and around the Yucatan Peninsula. Because the area of low pressure was under the influence of a nearby upper-level trough, Alberto was designated as a subtropical storm by the National Hurricane Center (NHC) on the morning of Friday May 25th, which is rather unusual as most subtropical storms form at higher latitudes. The storm initially formed just east of the Yucatan Peninsula. A large subtropical ridge over the southwestern Atlantic steered Alberto on a northward track, and the storm brushed the far

At 10:00 AM CDT today the National Hurricane Center (NHC) upgraded low pressure center (90L) to Subtropical Storm Alberto. Alberto moved over the waters of the northwestern Caribbean Sea. Alberto is expected to bring heavy rainfall and flash flooding to the northeastern Yucatan, western Cuba and Florida over the Memorial Day weekend. The GPM core observatory satellite passed above the Yucatan Peninsula on May 24, 2018 a 11:19 PM EDT (May 25, 2018 at 0319 UTC). With this pass GPM saw areas of heavy precipitation within the western Caribbean and in the Gulf Of Mexico west of Cuba. GPM's Dual

The second tropical cyclone in less than a week has formed in the western Arabian Sea early on May 22, 2018. This tropical cyclone called MEKUNU is intensifying as it heads toward Oman. The Joint Typhoon Warning Center (JTWC) predicts that MEKUNU will have winds of about 85 kts (98 mph) when it hits southwestern Oman in about three days. This will make it the equivalent of a category two hurricane on the Saffir-Simpson hurricane wind scale. Tropical cyclone MEKUNU follows on the heels of destructive and deadly tropical cyclone SAGAR that just made landfall over northwestern Somalia a few days

For close to two weeks the combination of a nearly stationary front and tropical moisture caused almost continuous precipitation over much of the Mid-Atlantic. Record amounts of rain fell over the eastern United States with over a foot of rain reported in some parts of the Mid-Atlantic. The excessive rain led to flooding along several rivers including the Potomac river. This image shows anomalous rainfall for the period from May 11-20, 2018. This analysis used climatology data that were based on measurements by the Tropical Rainfall Measuring Mission (TRMM) satellite from 1997- 2015. The TRMM

Last week Tasmanian's were evacuated, businesses were flooded and cars washed away as extreme rainfall accompanied a strong cold front and a low pressure system that spawned violent storms. Hobart city, located in southeastern Tasmania, received record breaking rainfall of more than 100 mm (3.93 inches) in a single day. A strong pressure gradient developed between the complex low pressure center over Tasmania and high pressure that was moving eastward over the Great Australian Bight (Southern Ocean). This strong pressure gradient resulted in destructively high south-easterly winds over

This past week, something rather unusual happened off the coast of Chile: a rare subtropical storm formed in the Southeast Pacific Ocean. Cyclone season is winding down in the Southwest Pacific near Australia where it is common for several tropical storms to form every year, but in the Southeast Pacific tropical storms are unheard of. This particular storm is a subtropical storm, which is a sort of a hybrid between a tropical cyclone like a hurricane, which gets it energy primarily from the condensation of humid air that forms over warm ocean waters, and an extratropical storm, which has a