July Slumber Continues in the Atlantic While the Eastern Pacific Heats Up

After an anemic start, the eastern Pacific is catching up to climatology

Friday morning satellite of the tropical Atlantic showing an extensive Saharan dust plume pushing westward. Dusty, windy conditions are expected to keep the Atlantic quiet into next week. Credit: NOAA.

As we discussed in previous newsletters, after a busy June, the Atlantic continues to take an expected and much welcome summer break to start July.

While several tropical disturbances dot the Atlantic this morning, including a vigorous tropical wave approaching the islands of the eastern Caribbean, a hefty dose of wind shear across the deep tropics will prevent any organized development into next week.

Meanwhile over in the eastern Pacific, which didn’t record its first system until last week – a record slow start for the basin – activity has finally picked up. Two areas of low pressure separated by 1,000 miles – one south of Central America and the other south of Mexico – each have a high chance of formation in the days ahead.

While neither poses a threat to land, their development should bring eastern Pacific seasonal activity back to near-normal levels.

The tick up in activity across the eastern Pacific is expected for mid-summer. Whereas the Atlantic has one very pronounced peak of hurricane activity in late August and September, the eastern Pacific tends to see a camelback progression of hurricane activity, with an initial peak in July followed by a more pronounced secondary peak in late August and September.

On the flip side, the Atlantic is often very quiet in July. In about one out of every three Julys over the past 50 years, the Atlantic hasn’t recorded a single tropical storm or hurricane. These stormless Julys included some very big hurricane seasons like 2004 and 1999.

Hopefully this season can behave more like 2009 or 1983, both of which had stormless Julys and below average hurricane seasons courtesy of El Niño. But even 1983 – the least active hurricane season in over half a century – produced Hurricane Alicia, a powerful and destructive hurricane that caused widespread damage across southeastern Texas, including throughout downtown Houston, making it the costliest hurricane to hit the U.S. at the time.