Tropical Storm Andrea is forecast to weaken and move further out into the Atlantic Ocean, with no effects on land. There is still another disturbance in the East Pacific to watch out for, with a 70% chance of tropical cyclone formation in the next 7 days. Let’s take a look at each one, and the current atmospheric setup and conditions that are shaping these storms:
Here’s our current setup in the Atlantic Basin, to further understand what’s going on:
Looking at our current setup, we have areas of high pressure spanning from the Southeast United States and across the Atlantic west of the Sahara. Tropical Storm Andrea sits in the middle of the Atlantic, moving further northeast. Let’s take a closer look at Andrea:
Tropical Storm Andrea:
As I just mentioned, Andrea is moving in the northeast direction at about 20 mph and is forecast to weaken, so this tropical storm will have no effects on land. Andrea’s peak maximum sustained wind topped out around 40 mph, with a minimum central pressure of 1015mb. By the time you are reading this, Tropical Storm Andrea will most likely have weakened into a post-tropical depression or a remnant low pressure area, as it is moving further and further into colder waters:
For tropical systems to develop and stay strong, sea surface temperatures must be at least 26 degrees Celsius, and as you can see, Tropical Storm Andrea has encountered waters much too cold to not weaken, and will only experience even colder temperatures as it travels northeast. So, Andrea has definitely passed its prime and will most likely be dissipating off into the Atlantic by the time you read this post.
Another Disturbance in the East Pacific:
As you can see, we have another disturbance just south of Mexico and much of Central America. It is slowly moving in the west-northwestward direction, and the National Hurricane Center has this disturbance at a 70% chance of tropical formation in the next 7 days. A large area of low pressure has formed, and showers and thunderstorms in this area are becoming more organized. If this area is combined with the right environmental conditions, there is a very good chance this disturbance forms into a tropical cyclone of some sort in the next couple of days.
So, what environmental conditions do we need? Firstly, we have seen that sea surface temperatures in this specific are have remained very warm and are still more than warm enough to sustain tropical activity.
There also needs to be high relative humidity in the mid levels of the atmosphere, and when looking at a few different models, relative humidity in the area of interest will stay high for the rest of the week:
Low wind shear in the area is also crucial for tropical cyclones to form. In this model we can see very low wind shear in the area that this disturbance is currently headed for open up during the week, although there are some small patches of high wind shear that may have an effect on the disturbance’s development:
So, conditions and the current organization of the disturbance all point to its likely tropical formation. Of course, we will continue to watch this area in addition to Tropical Storm Andrea, so stay tuned to NickelBlock for more updates!
