|Above: Visible MODIS image of Hurricane Barbara from Tuesday afternoon, July 2, 2019. At the time, Barbara was a Category 4 storm with 140 mph winds, and would reach peak intensity of 155 mph winds about six hours later. Image credit: NASA.|
Spectacular natural fireworks were on display over the Eastern Pacific Ocean on Tuesday, when Hurricane Barbara exploded into a high-end Category 4 hurricane with 155-mph winds at the same time that the shadow of a total solar eclipse darkened the waters to its south.
A mere tropical storm with 70-mph winds at 11 am EDT July 1, Barbara rapidly intensified into a Category 4 storm with 130-mph winds just 18.5 hours later. By 11 pm July 2, Barbara had reached its peak intensity of 155 mph, falling just short of the 157-mph threshold needed for a Category 5 rating.
A weakening Barbara not a significant threat to Hawaii
Barbara’s intensity is now on the downswing, as the storm has crossed into a more stable airmass and appears to be undergoing an eyewall replacement cycle. At 11 am EDT Wednesday, Barbara’s top winds had decreased to 145 mph. The storm was located in the remote tropical Northeast Pacific, a little more than 1900 miles east of Hilo Hawaii, moving west-northwest at 10 mph.
Barbara's weakening trend will accelerate by Thursday, as wind shear increases to a moderately high 15 – 20 knots and Barbara moves over cooler waters below 26°C (79°F), the standard benchmark for tropical development. By the weekend, a fast-weakening Barbara will turn more to the west toward the Hawaiian Islands. During the weekend, Barbara will be over cool ocean waters of 25 – 25.5°C (77 - 78°F) and be under very high wind shear of 30 – 35 knots. NHC is predicting Barbara to degrade to a tropical storm on Saturday and dissipate on Sunday.
Moisture from Barbara plus any remnant post-tropical circulation may brush the Hawaiian Islands beginning on Monday, perhaps bringing squally conditions and localized heavy rains. (Just a few days ago, on June 25, Honolulu picked up 4.20” of rain—the city’s heaviest rainfall on any day outside of the October-to-April wet season in city records that go back to 1877. Official rainfall measurements have been taken at the Honolulu airport since 1940.)
Watch as #HurricaneBarbara develops an eye in this #GOESWest loop from July 2, 2019. While Barbara remains a Cat. 4 hurricane, gradual weakening is expected throughout the day. More imagery: https://t.co/vJU1Ct5MKl pic.twitter.com/yiY6YRWqA5— NOAA Satellites (@NOAASatellites) July 3, 2019
Barbara the second strongest tropical cyclone of 2019
Barbara is tied for 2nd place with Tropical Cyclone Fani for strongest tropical cyclone of 2019. Fani peaked as a top-end Category 4 storm with 155 mph winds as it approached landfall near Kolkata, India on May 2.
The strongest tropical cyclone so far in 2019 has been Super Typhoon Wutip, which peaked as a Category 5 storm with 160 mph winds in the waters about 300 miles west of Guam on February 25. Wutip was the first Category 5 storm ever observed in the Northern Hemisphere in February.
Eastern Pacific hurricane season suddenly quite active
The Eastern Pacific hurricane season got off to a slow start in 2019, with last week’s Alvin arriving at the third latest date on record for the season’s first named storm. However, the Eastern Pacific is cranking now. Barbara is already the second hurricane of the season, and the Eastern Pacific typically does not see its second hurricane until July 14; the usual appearance for the season’s first major hurricane is not until July 19.
The season’s third named storm usually appears by July 5; we are likely to be right on schedule in that regard, with the models predicting the formation of Tropical Storm Cosme early next week. In their 8 am EDT Wednesday Tropical Weather Outlook, NHC gave 2-day and 5-day formation odds of 20% and 80%, respectively, for the season’s third tropical cyclone. Looking ahead, the GFS models is predicting the possible formation of the season’s fourth tropical cyclone late next week—though it is unwise to put a lot of faith in a tropical cyclone genesis forecast so far into the future.
Have a great Fourth of July holiday, those of you in the U.S.!
Bob Henson contributed to this post.