A couple of factors may be impeding the storm’s development. The first factor is a lot of dry air and Saharan dust in the vicinity of the storm. You can see all the dry air in this image below on the left. Click the image for a larger view. The dry air is colored red.

The image on the right shows the amount of wind shear (turning of the wind with height) that the storm is encountering. Wind shear inhibits the development of tropical systems. Light winds in the upper atmosphere are favorable for storms to develop. This storm, although not hitting extremely strong wind shear, is entering an area of increasing wind shear. This is most likely contributing to the storm’s slow development.

The third image is sea surface temperature. You can see that ocean temps are warm throughout the Eastern Atlantic near the storm. The sea surface temperature is not a negative contributor to the storm’s development.

The storm is still likely to reach Tropical Storm (Ana) strength within 24 hours. It may not, however, become a hurricane. The long-range computer models are not too bullish on the intensity forecast. Many of the projections keep the storm between 50-65 mph for several days to come.

The Tropical Wave that is off the coast of Africa is showing more potential to develop. At this point, the National Hurricane Center says there is about a 30-50% chance that this becomes a tropic cyclone in the next 48 hours.