What a difference 24 hours makes. Mainly in terms of the ebb and flow of weather model cycles which love to play on our meteorological heartstrings. Fortunately we have the here and now to ground us. Monday night, we were watching two ill defined areas of low pressure. Now, we're still watching two ill defined areas of low pressure. This isn't to downplay the possible development of Invest 96-L, the broad spin of clouds about 1,000 miles (give or take) southeast of Puerto Rico. But with social media posting snapshots of nine-day forecasts and bowling balls of spin rolling into the Gulf of Mexico, it's easy to lose the forest for the trees. In a sense the safest place to be is at the end of a 9-day weather forecast. So why is this one striking such a chord? Well it's late August. It's the time of year when strong hurricanes can form. Camille and Katrina, two of the strongest hurricanes on record, were both August storms. But it's also the expected westward movement, thanks to a sprawling ridge of high pressure to the north, that will guide 96-L across the Lesser Antilles and into the Caribbean this weekend, that gives us more pause for concern. One thing we do know: the islands of the eastern Caribbean, including Puerto Rico and the U.S. Virgin Islands, will be impacted by (at least) heavy rainfall and squally weather by late week into Saturday. The verdict is still out on whether 96-L could organize into a tropical depression or tropical storm before then, but the ocean and atmosphere ahead won't exactly discourage it. By Friday a dip in the jet stream off the U.S. east coast will begin to pinch off the high pressure steering, at which point 96-L, or whatever comes of it, could begin to feel a little tug northward from a channel carved out by the jet stream. On the other hand, it could continue plodding westward through the central Caribbean and toward the Gulf of Mexico if the channel isn't strong enough or the system stays weak. This fork in the road wouldn't occur until late weekend into early next week, five or more days from now at which point our forecasting ability begins to drop off. Bottom line: it's far too soon to say what if any impacts 96-L might have on the mainland U.S. Given the general steering pattern and overall favorable conditions ahead it's at least one to watch over the next few days. But first we need to see how and if it organizes tomorrow into Thursday.
