Oct 21st: Tropical Storm Melissa Forms
In case you missed it, the NHC upgraded Invest 98L to Tropical Storm Melissa earlier today. As you can see by the satellite image, the low-level center is not co-located with the strongest convection, a feature that should limit strengthening in the near term:

The 5 pm NHC cone shows that slow strengthening and movement:
As far as its future, we have had consolidation in the models. First up, look at the last 4 runs of the Google AI model where we went from the two scenarios of a quick north turn over the island of Hispaniola or a slow westward movement before that north turn to now most members showing the slow westward movement before an eventual turn to the northeast:
The GFS is the lone hold out now with much of its members still showing that quick turn while the Euro continues what it has shown all along, a slow westward motion followed by that turn north:

Before we get to any potential US impacts down the road, it is important to discuss the risk for extreme rainfall over parts of the Caribbean due to the slow westward movement:

While the rainfall could be historic and catastrophic, we also can't ignore that the storm could develop into a strong hurricane over the very warm waters of the Caribbean. Not a single storm has gone through that area this season, leaving an untapped source of energy. You can see in the intensity forecast below that several models approach major hurricane strength:

As we mentioned yesterday, where exactly that northward turn occurs will determine what, if any, impacts the US gets. The models are still indicating a strong system moving into the eastern US just before Halloween. If Melissa gets too far west, the two systems could interact.
For now, we continue to monitor the storm and we should get more model consensus in the days to come, especially now that we have a true storm to track. It isn't unheard of to get storms this time of year and we've had some significant ones like Wilma in 2005 and Sandy in 2012. That's why many emergency managers and school districts rely on on-call meteorologists during the hurricane season. Our team can provide real-time briefings, forecast interpretations and risk alerts to help keep you informed. Reach out if you think your organization could benefit from these services:
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