There are currently three different active tropical cyclones in the Atlantic: Tropical Storm Jerry, Tropical Depression Karen, and Tropical Storm Lorenzo. Additionally, there is a new disturbance in the southern Gulf, near the Yucatan Peninsula, to watch.
This update will focus on Karen and the new disturbance in the Gulf, as Jerry is only an issue for Bermuda, and Lorenzo will be curving out to sea.
Karen
Karen is very, very disorganized this evening, and has weakened to a tropical depression; dry air and wind shear appear to be the cause.
Data from a reconnaissance aircraft, as well as satellite imagery, suggest the cyclone does not have a well-defined low-level circulation, but rather a broad one.
As of 8 PM EDT/AST, Karen had sustained winds of 35 mph, a minimum pressure of 1008 mb, and was moving north-northwest at 13 mph.
Karen will directly impact Puerto Rico/U.S. Virgin Islands Tuesday. Once north of Puerto Rico mid to late week, conditions are still forecast to be favorable for some re-intensification.
However, it should be noted that the GFS and HWRF show dissipation, while the ECMWF and UKMET show strengthening.
By Thursday/Friday, a ridge (high pressure) will build across the eastern U.S. and western Atlantic; this should cause a significant decrease in forward speed and/or a stall, and possibly a bend to the west/west-southwest after (see figure 2).
Due to the aforementioned model differences regarding intensity, it is too early to speculate on Karen’s fate beyond Friday.
With that said, the Bahamas, Florida and the U.S. East Coast should closely monitor Karen’s progress over the coming days.
New Gulf disturbance
A broad area of low pressure in the southern Gulf is producing disorganized convective activity.
While some development will be possible over the next 3 – 4 days, the ECMWF, UKMET and GFS weren’t predicting any development as of the 12z model cycle.
In their 8 PM EDT Tropical Weather Outlook, the National Hurricane Center put the 5-day development chance at 20 percent.
If a tropical cyclone does form, it likely won’t be of concern to the U.S. Gulf Coast.
