This an archive of a former Wikipedia article.

Hurricane Boris was the second tropical depression, tropical storm, and hurricane of the 1990 Pacific hurricane season.

Meteorological history

A tropical wave came off the northwest coast of Africa, on May 20. The wave made an uneventful course, as it moved west, across the Atlantic Ocean and Caribbean Sea. However, as it crossed Central America into the warm-watered eastern Pacific Ocean, its cloudiness increased considerably on May 31. The wave quickly moved northward, as it reached the waters of the Pacific.[1]

It became Tropical Depression Two-E on June 2, indicated by satellite and ship report analysis. After becoming a depression, 2-E moved in a west to northwestward direction. Upper-level easterly shear limited the amount of the initial strengthening. However, satellites observations later showed an increase in convective banding, and 2-E became Tropical Storm Boris on June 4, Template:Convert/LoffAoffDbSoff southwest of Manhandle. By June 5, Boris was upgraded to a hurricane based on Dvorak intensity analysis, as the system had formed its own anticyclone. The hurricane also began to move more north-northwestward, in response to a trough off of the West Coast of the United States. It also underwent further strengthening, as it reached its peak strength of Template:Convert/mi/h, and a minimum air pressure of 977 mbar.

The hurricane's cloud pattern became longer along its southwest and northeast sectors on June 6, due to an increased amount of shearing and an influence of the California Current . Boris was downgraded to a tropical storm later in the day on June 6. The deep convection of the tropical storm decreased, as Boris moved into areas with even cooler water temperatures. It was downgraded to a tropical depression on June 7, due to these factors. The depression weakened a little more. Soon thereafter, Boris began rapidly losing its tropical characteristics on June 8, though a small circulation of clouds persisted off the northwest coast of Baja California, for a few days. [1][2] Boris hit the California Coast a few days after it went extratropical.

Preparations and Impact

Due Boris was already extratropical no watches or warning were issued. If it was a tropical cyclone the NHC would have probably issued a tropical storm watch for Souther California. The winds in the eyewall of Boris ripped off the sails of the Azzure Dream sailboat. No other direct damages or casualties were reported from Boris.[1][3][4]

Boris brought rain to the southwest. Despite causing the wettest June in San Diego since records began in 1850, less than an inch of rain fell at that location.[3][5] Rainfall from Boris was mainly scattered. Despite that fact rain was reported as far east as Wyoming, becoming the second wettest Tropical Cyclone there.[6] Boris brought heavy rain to Utah becoming one of the wettest there. Boris also was one of the wettest tropical cyclones in Nevada peaking at Lund.[6] In, California Boris's rain was tenth wetest in states history due it was mainly light.[6]


  1. 1.0 1.1 1.2 Max Mayfield (1990). "Hurricane Boris Prelim 1". National Hurricane Center. Retrieved 2006-12-01. 
  2. Avila (1990). "Hurricane Boris: Tropical Cyclone Discussion June 8 1421Z". National Hurricane Center. Retrieved 2006-12-01. 
  3. 3.0 3.1 Max Mayfield (1990). "Hurricane Boris Prelim 2". National Hurricane Center. Retrieved 2006-12-01. 
  4. Avila (1990). "Hurricane Boris: Tropical Cyclone Discussion June 3 2031Z". National Hurricane Center. Retrieved 2006-12-01. 
  5. HPC Boris Rainfall
  6. 6.0 6.1 6.2 David M. Roth. "Tropical Cyclone Rainfall for the West". Retrieved 2008-02-25.