Good evening everyone!
This will be a fairly brief update.
INVEST 91L has been re-activated, regarding the shower and thunderstorm activity I’ve been watching near and now over the Bahamas since the deactivation of 91L. The current NHC Tropical Weather Outlook as of 2:00 p.m. EDT indicates a LOW (20%) probability of the wave becoming a tropical cyclone during the next 48 hours.
Based on satellite and surface information, there are currently no indications of a closed circulation.
Analysis of the current wind shear product from CIMSS indicates shear values have remained only around 5-10 knots over the INVEST, and have continued to slowly decrease. Convective activity that has been occurring is being enhanced by a diffluent flow aloft…however upper divergence is weak at best, and lower convergence is lacking at the moment.
Based on the most recent run of the GFS wind shear and zonal shear forecast maps, shear is forecast to remain weak to non existent for the most part over the next 36 hours. This COULD allow for some further slow organization before it becomes part of a frontal boundary, should the INVEST cease to ingest drier air. Satellite loop imagery indicates drier air continues to be a problem, based on collapsing thunderstorm activity, and the presence of arc clouds (outflow boundaries) quickly moving away from the system.
The current steering flow at both 700-850 mb, and 500-850 mb indicates INVEST 91L will move toward the NW over the next 24-30 hours, with a turn toward the north, then another turn to the NNE or NE by 36-48 hours, based on the current run of the forecast steering layers maps from the PSU e-WALL site. This INVEST is forecast to pas close enough, to bring showers and gusty winds to the South Florida coastal waters during Fri/Sat.
I will continue to monitor this INVEST as it becomes part of the frontal boundary, to see if baroclinic forcing has any affect on it.
Have a blessed evening!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)