Looking Back on Hurricane Season's Most Active Julys
While very active Julys can accompany busy hurricane seasons, not all years come with a July warning
We’re now through the first 35 days of the 183-day hurricane season, or roughly 20 percent down according to the Gregorian calendar. Mother Nature, however, operates on its own timelines, and the record books remind us that a whopping 98 percent of hurricane season activity typically comes after July 5th. Hurricane season moves more like a tall rollercoaster – with a slow start and quick climb – than like a smooth Sunday drive. We’re sometimes fooled by the slow starts but by November we’re ready for the ride to end.
July is the in-between place of hurricane season. Most Julys are lucky to eke out a meager 5% of total hurricane season activity. In busier Julys like 2005 or 1997, we might see a quarter of total seasonal activity. Even so, for about half of all Julys in the 173-year historical record, the Atlantic recorded zero tropical systems for the month. Suffice it to say, in July we’re usually only a coin flip away from tropical tumbleweeds.
Of course, July can bring plentiful activity, and unlike June, July has recorded stronger Category 4 and 5 hurricanes. Category 4 Hurricane Dennis and Category 5 Hurricane Emily – both in 2005 – were recent powerful July hurricanes.
Not surprisingly largely due to Dennis and Emily, 2005 tops the list as the most active July on record, followed by July 1916, July 2008, and July 1933. While each of these years brought active hurricane seasons, other years with above average July activity like 1997 finished quietly.
As we’ve discussed in previous newsletters, hurricane season activity in June and July doesn’t tell us much about what the busier months might bring. Julys with no tropical activity are especially deceiving. 2004, 1950, and 1999 observed no tropical cyclones in July but were three of the busiest hurricane seasons on record. July teaches us to not get out over our skis and to stay patient and keep vigilant into August, September, and October, when the lion’s share of tropical activity happens.
Nothing’s brewing this week across the tropics. A big surge of Saharan dust from northern Africa is being heaved into the Atlantic today while hostile wind shear lays claim to the basin.
For now at least the usual July slumber will give all of us in the hurricane zone an extended holiday.