A broad area of low pressure, re-designated Invest 91E, continues to produce disorganized showers and thunderstorms off the Nicaragua coast. This system should remain nearly stationary and perhaps meander slightly over the next several days, and could develop into a tropical cyclone if it does not move inland into Central America.

As of 18:00 UTC Wednesday, Invest 91E was located near 11.8°N 87.3°W. Maximum sustained winds were 25 knots (30 mph), with an estimated minimum pressure of 1006 mb. Invest 91E has become a little better organized today, though deep convection has decreased some this afternoon. The National Hurricane Center (NHC) gives 91E a 30 percent chance of development within 48 hours, and a 50 percent chance within five days.

The future evolution of 91E is complicated. Models have been on and off with development, because the track is uncertain. The environment for 91E is quite favorable for strengthening. Based on the 18z SHIPS model, wind shear is expected to remain less than 15 knots while 91E remains over sea surface temperatures near 29°C (84.2°F) for the next five days. In addition, 91E is embedded in a very moist mid-level environment, as the upward phase of the Madden-Julian Oscillation (MJO) is in the region.

If 91E tracks westward and avoids land, significant development is possible, but this scenario appears less likely today. If 91E remains nearly stationary, some slight development is possible, and a weak tropical cyclone could make landfall in Guatemala or El Salvador. If 91E tracks eastward, it would likely move inland into central America with no development. The GFS and UKMET models show some slight development with 91E, while the ECMWF buries 91E into Central America with no development. Interests along the Pacific coast of Guatemala, El Salvador and Southern Mexico should monitor the progress of 91E over the coming days. If 91E develops into a tropical storm, it will be named Alvin.

If 91E does move inland into Central America, it may be absorbed by a larger cyclonic gyre, which could lead to the formation of a broad area of low pressure in the Northwestern Caribbean. The GFS model shows this scenario, redeveloping 91E over the Northwestern Caribbean. The ECMWF model does not show any development on the Atlantic side. I will continue to monitor this, but right now, I think development in the eastern Pacific is more likely, at least in the short term.