Happy Fourth of July everyone!
Not much change in the Tropics this morning from the past 2 days. An area of showers and thunderstorms still persists over the Yucatan Peninsula, GOMEX, and over the Panhandle of Florida, extending into portions of Alabama and Georgia. This disturbed weather is associated with a broad trough (trof) of low pressure in the GOMEX. Upper level winds are not conducive at this time for development, and will only be marginal for any development in about 3 days. The NHC indicates in their Graphical TWO this area has a LOW (10%) chance of becoming a Tropical Cyclone during the next 48 hours.
Based on current steering, and analysis of Forecast Steering Layers maps, this area should move slowly toward the N-NNE over the next 48-72 hours.
Based on the current Wind Shear / Zonal Shear forecast from the GFS, I am not expecting development in this area over the next 72 hours. However, we do have a strange scenario in that the NCEP Ensemble Models Cyclogenesis forecast indicates a fairly high chance for cyclogenesis in the BOC between the next 48-120 hours in the forecast period from 06Z this morning. Albeit based on the Wind Shear forecast, and lack of Global Model support for cyclogenesis, and at the moment I am discounting the scenario, I will continue to monitor the BOC area over the next 72 hours, given the Ensemble Models have been persistent for the past 3 days with the high chance for cyclogenesis.
There COULD be a slim possibility of increased convective activity over the area as even though we now have a weak MJO signal over the GOMEX / W. Caribbean area, the MJO Multivariate Index Phase Diagram forecast seems to indicate the MJO extending back a little stronger into Octant 1 over the next few days, before we lose the MJO totally. I am basing this off the GFS forecast, as it seems to have handled the MJO the closest, based on the current phase diagram, and forecast diagram from the GFS vs. the ECMWF.
The following is the forecast graphic from CPC using the GFS MJO forecast. One thing about this graphic…if this holds true, I would expect further cooling of SST Anomalies in the Nino 3.4 region.
As stated in my previous forecasts, should there be no development in the BOC / GOMEX region within the time frame specified, I believe our next development will come out of the MDR, as the Wind Shear forecast pretty much indicates the Caribbean basin will be shut down over the next 14 days.
The most current NAO forecast indicates the NAO should be heading back to negative and be within the negative value range after mid month. This may present the chance for at least two conditions to occur should this come to fruition, and hold for the remainder of July thereafter…we should see a further warming of SST anomalies in the MDR, and we should see weaker trades reducing shear, and allowing for heat to pile up in the Atlantic.
Elsewhere, and area of disturbed weather south of the Cape Verde Islands is associated with the ITCZ and enhancement at the southern end of a wave axis. Albeit climatology dictates lack of development in this area, I will continue to monitor this area for any significant changes, as the Zonal Shear forecast indicates somewhat conducive upper level winds over the area during the next 7-10 days. Also based on analysis of the Zonal Shear forecast, any development that may occur during this time, and after mid month, I believe will not take place before 40-45W Longitude.
Tropical Storm formation is not expected through the next 48 hours.
Have a blessed day!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)