California

IMERG rainfall totals from Hurricane Hilary.
Hurricane Hilary is being hailed as a historic storm after becoming the first tropical storm to hit California since Sept. 24, 1939. The storm has had a large impact on the region - in addition to gusty winds, Hilary’s rains have resulted in widespread flooding, landslides, washed out roads and numerous other closures. Like most East Pacific tropical cyclones, Hilary originated from a westward propagating tropical wave that crossed over Central America from the western Caribbean into the eastern Pacific. Known as “African easterly waves”, these are the same waves that emerge off the coast of
IMERG Rainfall Total from Week of Jan 25 2021
NASA combined data from multiple satellites to estimate the rainfall from an "atmospheric river" event over the U.S. West Coast in near real-time at half-hourly intervals from January 25 - 29, 2021. Atmospheric rivers are long, narrow corridors of water vapor that can lead to heavy precipitation when they encounter land. This animation shows estimated rainfall rates in blue and yellow shading and total rainfall accumulations in green shading, from NASA's IMERG algorithm, overlaid on shades of white and gray from NOAA infrared satellite data which shows cloudiness. On January 25, 2021, a low

IMERG Measures Flooding Rainfall In Deadly California Wildfire Areas

Heavy precipitation has been falling in areas of California that were recently devastated by deadly wildfires. This flooding rainfall has resulted in evacuations in burn scarred areas such as Butte County where the deadly Camp Fire hit this month. Flash floods, debris flows and mudslides are now predicted in areas where deadly wildfires stripped away vegetation. On a positive note these Pacific storms are expected to dampen wildfires and replenish the Sierra Nevada snowpack. This snowpack is an important source of water for California's streams and rivers. NASA's Integrated Multi-satellitE

GPM View Hurricane Rosa in the Eastern Pacific

The GMI overflight here shows a clear center of circulation with much of the intense convection on the south side of Hurricane Rosa, a Category 1 storm with winds of 75 knots. It is expected to continue intensifying over the next couple days before it runs into strong shear and cooler waters off the Baja California coast. Forecasts suggest it will make landfall in Northern Baja as a tropical storm, with its primary impacts being heavy rainfall and flash flooding over the Desert Southwest.

Heavy Rainfall Leads To Deadly California Mudslides

Winter rains falling on recently burned ground triggered deadly mudslides near Santa Barbara, California on the 9th of January. The potential for landslides is shown above. It was generated by the global Landslide Hazard Assessment for Situational Awareness (LHASA) model, a model that combines GPM precipitation data with a global landslide susceptibility map. LHASA gives a broad overview of landslide hazard in nearly real time, but site-specific information should be obtained prior to emergency operations or building projects. At least 15 residents of southern California have been killed by
Another Pineapple Express Brings More Rain, Flooding to California
The West Coast is once again feeling the effects of the "Pineapple Express". Back in early January one of these "atmospheric river" events, which taps into tropical moisture from as far away as the Hawaiian Islands, brought heavy rains from Washington and Oregon all the way down to southern California. This second time around, many of those same areas were hit again. The current rains are a result of 3 separate surges of moisture impacting the the West Coast. The first such surge in this current event began impacting the Pacific coastal regions of Washington, Oregon, and northern California on...

Mudslides & Flooding Produced By Extreme Rainfall Over Southern California

It is sunny in southern California today but recent unusually heavy rainfall led to rock slides, mudslides and flooding in that part of the country. Rainfall of almost 4 inches (101.6 mm) in one day was reported in Long Beach, California. Some highways in the area were flooded due to intense downpours. Rainfall since the fall of 2016 has improved drought conditions over northern California but Southern California has been slower to improve because of the exceptional rainfall deficit in that area. NASA's Integrated Multi-satellitE Retrievals for GPM (IMERG) were used to estimate the total

Pineapple Express Delivers Heavy Rains, Flooding, Drought Relief to California

An atmospheric river (“Pineapple Express”) delivered over 5 inches of rainfall in parts of California during January 3-10, 2017 (bottom) as viewed by GPM’s IMERG data. California, which has long been suffering through a strong, multi-year drought, is finally beginning to see some much needed relief as a result of a recent series of storms that are part of a weather pattern known as the “Pineapple Express.” The Pineapple Express is known as an atmospheric river. A large, slow-moving low pressure center off of the West Coast taps into tropical moisture originating from as far south as the

IMERG Analyzes El Niño Fueled California Storms

After a break in February, El Nino fueled storms have started pounding California as they move in from the Pacific Ocean. Northern California has been especially hard hit with heavy rainfall and strong winds being reported. Heavy rainfall north of Sacramento caused flooding that killed a woman in Olivehurst, California. Rain and snowfall in the Sierra Nevada mountains may help to alleviate the long lasting California drought. An analysis of total precipitation from February 29 to March 7, 1016 was accomplished using data collected by NASA's Multi-satellitE Retrievals for GPM (IMERG). This
California “Rain Debt” Equal to Average Full Year of Precipitation
California's accumulated precipitation “deficit” from 2012 to 2014 shown as a percent change from the 17-year average based on TRMM multi-satellite observations. Credits: NASA/Goddard Scientific Visualization Studio A new NASA study has concluded California accumulated a debt of about 20 inches of precipitation between 2012 and 2015 -- the average amount expected to fall in the state in a single year. The deficit was driven primarily by a lack of air currents moving inland from the Pacific Ocean that are rich in water vapor. In an average year, 20 to 50 percent of California's precipitation...