“Pineapple Express” – Atmospheric flow drenches California and blasts dangerous winds
#Pineapple #Express #Atmospheric #flow #drenches #California #blasts #dangerous #winds Welcome to Alaska Green Light Blog, here is the new story we have for you today:
The latest in a series of atmospheric flows to soak the state was accompanied by dangerous winds, leaving thousands without power.
Just four days after heavy rains hit California, the state was drenched by another atmospheric storm on January 4-5, 2023, causing flooding, downed trees and power lines.
According to the National Weather Service, coastal California wind speeds of 40 to 80 miles per hour. Wind speeds were exceeded on the evening of January 4th 100 miles per hour near Lake Tahoe. About 1 to 3 inches of rain fell on communities near Santa Cruz and San Francisco on the evening of January 4, but the storm continued to drop rain on the Bay Area as it moved east on January 5. Some areas south of Big Sur saw 6 to 8 inches of rain in 24 hours.
This map shows all precipitable water vapor in the atmosphere at 5:30 am Pacific Standard Time on January 4, 2023. Precipitatable water vapor is the amount of water in a column of the atmosphere if all water vapor were condensed into liquid. Dark green areas on the map show a narrow band of moisture flowing from the tropical Pacific toward the west coast, making this atmospheric flow an example of a “Pineapple Express.The image was derived from NASA’s Goddard Earth Observing System, Atmospheric Data Assimilation System (GEOS ADAS), which uses satellite data and models of physical processes to calculate what’s happening in the atmosphere.
The string of atmospheric flows that have drenched California in recent days could be seen as welcome relief from the state’s ongoing drought. Atmospheric fluxes occur regularly in winter, making up to 50 percent of all rain and snow that falls in the western United States. However, the rapid succession of atmospheric flows makes communities more vulnerable to flooding and could cause landslides.
The above image was acquired on January 4, 2023 at 1:20 p.m. Pacific Standard Time by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the NOAA-20 satellite. It shows the storm intensifying, which contributed to the high wind speeds. When the air pressure in a mid-latitude cyclone drops rapidly and winds pick up, these storms can undergo a process meteorologists call it bomb arches. Storms with central pressures falling by an average of at least 1 millibar per hour for 24 hours are sometimes referred to as “bomb cyclones.”
Downed power lines contributed to the fact that more than 170,000 homes were left without power on the morning of January 5, it said PowerOutage.us. Most outages have been observed in coastal counties such as Mendocino, Sonoma and San Mateo.
Atmospheric flows are among the most damaging storm types in the mid-latitudes, especially given the dangerous winds they produce research led by Duane Welsh at NASA’s Jet Propulsion Laboratory. Welzer and colleagues examined the most destructive storms of the last 20 years – the top 2 percent in terms of near-surface wind speeds – and found that atmospheric fluxes were associated with them up to half of these storms.
When Californians got rid of this latest storm system, the National Weather Service Weather Forecast Center expects more atmospheric fluxes to reach the state on January 7-9, 2023.
NASA Earth Observatory images by Lauren Dauphin using GEOS-5 data from the Global Modeling and Assimilation Office at NASA GSFC and VIIRS data from NASA EOSDIS LANCE, GIBS/Worldviewand the Common Polar satellite system (JPSS).