Strong tropical wave cruising through Caribbean Sea

The average formation date of the fifth named storm is August 30, but this year, it will likely arrive early.  The African easterly wave we've been tracking for a bit over a week now is much better organized and is very close to being upgraded to Tropical Storm Earl.  An aircraft reconnaissance plane will fly into it later today to try to find a closed surface circulation -- its rapid motion makes it harder to meet this requirement.  It is centered south of Hispaniola and is moving quickly to the west.  I marked the approximate center with a blue X in the satellite image below.  It is a compact system, but rainbands are affecting Haiti and Dominican Republic today.

Environmental conditions are favorable for further development... vertical wind shear is forecast to remain in in the 5-15 kt range throughout the week, and sea surface temperatures are adequate now and will increase as the storm moves west.

Models continue to agree on a westward track across the rest of the Caribbean, bringing it to the Yucatan peninsula or Belize on Wednesday.  It would weaken as it crosses land, so whatever emerges in the Bay of Campeche will have some reorganizing to do before it poses a major threat somewhere else.  At this point, a south Texas impact looks very unlikely, but it's far too early to completely rule it out.

I plotted the tracks of the past fifteen "E" storms just for reference (2001-2015)... seven of them became hurricanes, and the one that most closely resembles this year's storm is 2012's Ernesto.  The strongest was 2005's Emily, which became a 140-kt Category 5 storm near Jamaica.  Both Ernesto and Emily traveled the full length of the Caribbean and both hit the Yucatan peninsula as hurricanes.

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