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Alberto weakening?

Convection has diminished over TS Alberto this afternoon. This may be partially due to the usual diurnal variation in the tropics, as the afternoon is when there is the least amount of convection. However, the warmer cloud tops of the thunderstorms may also be a sign that shear is once again adversely affecting Alberto. A NOAA P-3 plane is currently investigating Alberto and is finding slightly weaker winds at flight level, 70 kts (now) versus 74 kts (this morning). The intermediate advisory from NHC comes out at 2PM, but I doubt there is enough evidence to lower the intensity at this point. It would not surprise me, however, if they lower the intensity at 5PM. Stay tuned to The StormTrack for more.

Figure 1. Infrared satellite imagery from 9AM (top), 11AM (middle), and 1PM (bottom) of TS Alberto. Notice how the cloud tops have warmed over the last 4 hours. (Source: NHC)

EDIT: Addition by Bryan Woods: I agree that Alberto is weakening but disagree with Adam's reasoning. I already posted about the role of the Loop Current in this storm. I think since Alberto is past the loop current, the Ekman pumping is again contributing a negative feedback to the storm. In short, the warm water layer is very shallow this early in the season and a lot of models don't handle that well. See my previous post for more.

EDIT2: Adam's Response: Bryan is right and I was a goober for not including that in my post. Thanks for keeping me honest.

Posted by Adam Moyer | Permalink