A tropical wave entered the Atlantic on August 23 from the west African coastline and traversed the tropical Atlantic. It began to show signs of development around the 27th, but the process was slow, and the wave was still moving quickly at a low latitude. Early on August 30, the system passed through the Windward Islands. During its trek through the eastern Caribbean, the wave looked much better on satellite imagery, but there was little "under the hood": any low-level vorticity was way south near the South American coastline.
A low pressure center developed a bit later as the system near Jamaica and brought heavy rainfall there beginning late on August 31. After that, a vigorous circulation spun up rapidly and Tropical Storm Nana was named during the afternoon of September 1, already with 50 mph winds! At the time it was located south of Jamaica. Nana broke the earliest "N" storm record, previously held by Nate of 2005, which formed on September 5 of that year.
Aiding Nana were warm ocean temperatures and a moist atmosphere. Hindering it was moderate shear out of the north. This lead to a pattern of oscillating convective bursts: the storm would develop a central dense overcast only to have it retreat toward the south. This limited Nana to a slow rate of strengthening as it continued west, but there was plenty of rainfall on the south side that affected Honduras on September 2. It had enough time to reach category 1 hurricane strength late that evening. It peaked at sustained winds 75 mph winds and a pressure of 994 mb before it made landfall in southern Belize overnight.
Once inland, Nana turned a bit more south of west and rapid weakening ensued. This fortunately limited rainfall totals over Belize and Guatemala. By late afternoon on September 3, the cyclone was a tropical depression. Within a matter of hours, it dissipated over mountainous inland Mexico. The next day, the remnants of Nana emerged into the Gulf of Tehuantepec in the Pacific Ocean, just south of the narrowest isthmus of Mexico. On September 5, these remnants spawned Tropical Storm Julio in the Pacific (the storm received a new name because the low-level circulation of Nana dissipated before reforming). This short-lived storm moved out into the open Pacific before dissipating on the 7th.
The above images shows Nana as a tropical storm on September 2. The cyclone was small and compact and the low-level cloud arcs visible in the northern half of the circulation indicate the effects of wind shear on the system.
Nana dissipated over Mexico, but its remnants moved over the Pacific Ocean.
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