| Above: Invest 90E as seen on Sunday afternoon, May 7, 2017, by the VIIRS instrument on the Suomi satellite. Image credit: NASA. |
The Eastern Pacific hurricane season, which officially begins on May 15, could get off to a record early start this year. The earliest a tropical depression has been recorded in the Eastern Pacific since reliable satellite records began in 1970 was on May 12, 1990, when Tropical Storm Alma got its start. Three other systems got their start on May 13, according to NOAA’s Historical Hurricane Tracks website. However, the basin’s first “Invest” of 2017, Invest 90E, has a chance to beat the record.
90E is an area of disturbed weather a few hundred miles southwest of the coast of Central America. Satellite imagery on Monday morning showed that Invest 90E was producing disorganized shower and thunderstorm activity, which was steadily increasing in areal coverage and intensity. Conditions were favorable for development, with the 12Z (8 am EDT) Monday run of the SHIPS model diagnosing light wind shear of 5 – 10 knots. Ocean temperatures were a very warm 30°C (86°F), which was about 0.5°C above average for this time of year.
Our three top models for predicting tropical cyclone genesis, the European, GFS and UKMET models, all predicted in their 0Z Monday runs that 90E would develop into a tropical depression by late this week. These models had 90E maintaining a west-northwest to northwest track parallel to the coast, followed by a turn more to the north, with a landfall between El Salvador and Southeastern Mexico late this week or early next week. In their 11:45 am PDT Sunday Special Tropical Weather Outlook, the National Hurricane Center (NHC) gave 90E 2-day and 5-day odds of development of 20% and 70%, respectively. NHC also highlighted a separate area of disturbed weather a few hundred miles to the west-northwest of 90E, with 5-day odds of development of 10%. Adrian will be the name given to the first tropical storm of the 2017 season in the Eastern Pacific.
| Meanwhile, in the South Pacific, Tropical Cyclone Donna peaked as a Category 4 storm with 130 mph winds at 06 UTC May 8, 2017. Donna is expected to weaken as it moves to the southeast through the islands of New Caledonia. According to CSU hurricane scientist Phil Klotzbach, Donna is the strongest May Southern Hemisphere Tropical Cyclone on record. In the image below, we see Donna near peak intensity at 0250 UTC May 8, 2017. Image credit: NASA. |
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