Extreme Weather News

Tropical Storm Aletta Forms In Eastern Pacific

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.

Tropical Storm Aletta Forms In Eastern Pacific

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 Frequency Precipitation Radar (DPR) instruments. The satellite's GMI and DPR instruments had a good view of rainfall on Aletta's eastern side. The location of rainfall within GPM's 3-D radar scans (DPR Ku Band) is shown in lighter shades. Intense rain bands are shown by DPR spiraling into the tropical cyclone's eastern side. DPR found that rain in some of these powerful storms was falling at a rate of over 187 mm (7.4 inches).

Tropical Storm Aletta Forms In Eastern Pacific

GPM radar data (DPR Ku Band) were used here to show the 3-D structure of precipitation associated with tropical storm Aletta. Storm top heights were found by DPR reaching altitudes of over 12 km (10.5 miles) within powerful storms in rain bands wrapping around Aletta's eastern side. Cloud top height estimates over an area larger than the GPM swath were produced by blending measurements from GPM's radar (DPR Ku band) with cloud top heights based on the GOES-WEST satellite's infrared temperatures.

Tropical Storm Aletta Forms In Eastern Pacific

  • Images and caption by Hal Pierce (SSAI/NASA GSFC)