Tropical systems outside the official season of June through November are fairly rare, and most of them occur in early December or late May. However, tropical activity has been recorded in every month, and hurricanes have even formed in mid-winter.
This season is off to an early start — at least in the eastern Pacific. What does early hurricane season activity portend?
2014 Tropical Weather Season Gets Off To An Early Start
A tropical disturbance which the National Hurricane Center has given the somewhat unimaginative name “Invest 90E” will move across the Mexican coast near Manzanillo today.
Maximum winds are 35 miles per hour and it is doubtful the system will attain tropical storm strength (39 miles per hour). However, the system will have an outsized impact on Mexico and the southern United States.
Flooding and mudslides can be expected in mountainous areas of Mexico in the path of the disturbance, while some drought-relieveing rain will reach Texas today and tomorrow. Though this system is in the Pacific Ocean, where the historical data are sparse, we can look at early-season storms in the Atlantic and see if they have any implications for the upcoming hurricane season.
The History Of Early Season Storms
In the Atlantic Basin, tropical activity is not particularly rare outside the limits of the official season, but only ten storms during the December to May period have reached hurricane intensity. Seven of these were category one storms, two reached category two status, and a lone category three hurricane has been recorded.
Hurricane Able: May 15-23, 1951
Hurricane Able began as an extra-tropical low pressure center 300 miles south of Bermuda on a cold front that had passed off the Atlantic coast. It tracked northwest, but then turned southwest over the Gulf Stream and began a transition to a tropical system as it headed south. As the storm passed over the Bahamas, Able attained true tropical characteristics and category one winds. Able then looped back to the north, and as it passed off Cape Hatteras attained category three status (winds of 115 miles per hour), before weakening over the cooler waters of the Atlantic.
Able was not only the earliest-in-the-season category three storm ever recorded, it was also one of only four major storms (category three or higher) to form before the month of July since 1870.
The Most Unusual Hurricane, March 6-9, 1908
Since naming hurricanes didn’t begin until 1951 (Able was actually the first named storm), the March, 1908 hurricane goes under the extremely unimaginative name “Hurricane #1″). Whatever it is called, it is, as of the historical data we now possess, a unique storm: the only category two storm to exist in the months December through April.
Hurricane One formed northeast of the Leeward Islands and headed south-southwest. It attained hurricane strength before it reached the Virgin Islands, and category two strength as it passed into the Caribbean. The hurricane fizzled out in the eastern Caribbean, but not before it had produced winds of 100 miles per hour, the strongest on record by a longshot for a mid-winter tropical system.
What Does An Early Storm Mean For The Hurricane Season
Though the current disturbance formed in the Pacific Ocean, where there is not a long historical record, we can look at what happens when there is an early-season storm in the Atlantic.
- 1951, the year of Hurricane Able, produced ten tropical systems, below normal, and eight hurricanes, above normal.
- 1908, the year of Hurricane #1, saw ten tropical systems, below average, and six hurricanes, exactly average.
There is not much to conclude from these early hurricanes. The numbers and intensities of storms depend crucially on the upper air patterns, especially those that pertain at the time of peak seasonal activity, August and September. The developing El Nino could dampen activity in the Atlantic — or not.
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