Good day everyone!
Really not much change in Tropical Storm Gabrielle’s forecast, nor Hurricane Humberto’s.
Based on satellite loop imagery, Gabrielle continues to be a naked Low Level swirl.
Information in the NHC 5:00 A.M. EDT forecast discussion indicates although she will be over warm water, models are in good agreement of strong shear to be a factor, and the NHC is forecasting weakening in about 36 hours.
Tropical Storm Humberto became our first hurricane of the season, with maximum sustained winds of 75 mph. This makes Humberto a Category ONE hurricane on the Saffir – Simpson hurricane wind scale. Satellite loop imagery this morning did indicate a slight eye feature on what little bit of visible and RGB imagery was available.
Humberto has now begun a path more to the right, and should begin to move north soon. This motion is expected to continue for the next couple of days, and by Friday, a sharp turn toward the west is expected as the ridge becomes re-established north of the storm, and somewhat stronger. The NHC indicates only some slight to moderate strengthening over the next 24-36 hours. before conditions become less favorable and he begins to weaken.
I will continue to monitor Humberto during the next 72-96 hours for any changes to steering and upper level pattern.
Tropical Disturbance INVEST 93L is now located over the eastern Yucatan Peninsula. Earlier this morning, the NHC had reported this system was still disorganized, which is confirmed by earlier satellite imagery. However, in the past few hours, convection pretty much exploded over the center, and the system is better organized…in fact, if I didn’t know better, I’d say it looked almost to be a depression..although it appears most of the vorticity is more concentrated at the 700-500 mb level. Satellite loops do show however, the circulation seems to be pretty compact and tight at this time.
Crossing over the Yucatan Peninsula should disrupt this somewhat, however we are dealing with a system very similar to what we saw in Fernand. Being the core is not very large, and appears somewhat compact, tight, weak systems like this have no problem generally spinning up in the BOC. One factor for this is the shape of the Mexican coastline, which basically induces the effect of forced convergence, helping pile up warm air at the surface.
Currently, the wind shear map indicates upper level winds are somewhat marginal. The current GFS wind shear forecast still indicates upper level winds may become conducive for development of this disturbance, within about 24 hours of the disturbance entering the BOC. Based on this, I am calling for slow development during the first 24 hours in the BOC until I see whether or not a center reformation takes place, which is not unusual with a developing system with some disruption.
Again, as I have always stated, steering currents can change in a matter of hours. The Global Models have shifted their solution back further south, with a possible Tropical Storm making landfall in Central Mexico. However, this will most likely change 2-3 more times, until we have a well defined LLC. I will be watching this system closely, as even though models and guidance indicate a more west motion, water vapor loop imagery does not detect that deep of a ridge over the U.S., with a couple of mid-upper level lows which could induce a weakness over the GOMEX. So, I will monitor this closely for any significant changes to the steering currents over the next 48-72 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)