Tropical Storm Humberto has strengthened slightly, and maximum winds are near 50 mph. Based on the 5:00 p.m. EDT advisory from the NHC, the following information was posted, and is contained in the NHC Tracking Map:
Based on updated current and forecast steering layers maps, I have no reason to change forecast track thinking at the moment, as a weakness will protrude down from the Canary islands, and one in the CATL around 45-50W in about 48 hours (NHC now mentions this one in the discussion) and pull Humberto more toward the NNW abruptly. Based on this, I concur with the 18Z Dynamic Model Guidance and NHC official track. NHC track is marked as OFCI:
Based on current and forecast wind shear maps, I concur at the moment with the NHC intensity forecast, however, the forecast shear map does indicates a fairly strong 200 mb anticyclone over Humberto in about 10 hours, and remaining over the storm for at least 2 days. Based on this, and sst’s of 27-29C prior to Humberto reaching sst’s of >26C, I feel he could attain CAT2 status. Based on the still somewhat tilted nature of the storm, I have backed off somewhat on the possibility of just making CAT3 status prior to cooler sst’s, but not totally willing to discount this given the excellent outflow patter projected.
GFS WIND SHEAR FORECAST
Closer to home, the area if disturbed weather I mentioned this morning, near the Gulf of Honduras has moved little, and convection has diminished since this morning. However RGB and visible satellite loop imagery does show a cyclonic circulation.
Albeit current wind shear values are marginal at this time, the upper level wind map seems to indicate an outflow pattern may be developing. This may be valid, as the GFS wind shear forecast projects upper level winds to become more conducive in about 36 hours, with a building upper level anticyclone which may follow this disturbed weather WNW into the BOC, where the upper level anticyclone is forecast to become better defined. Buoy data closet to the area indicated at 3:00 p.m. MLSP of 29.84 in and falling, however this may be just diurnal changes.
NDBC STATION 42057
Based on current and forecast steering, I expect this to move slowly toward the WNW during the next 36-42 hours, before being turned toward the west as the U.S. ridge re-positions further to the west. Right now, this doesn’t appear to be any threat to the U.S.
I am still monitoring the remnant of Gabrielle for regeneration. In fact, upper level winds have relaxed somewhat, and a burst of convection is noted in visible and RGB satellite loops, just on the eastern edge of the circulation. Upper level winds are forecast to become briefly conducive over the next 24 hours, before becoming unfavorable shortly thereafter.
I will continue to monitor these areas for any significant changes to any forecast parameters.
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)