UPDATE…3:25 P.M. EDT…SEP. 06, 2013:
The disturbance which was located close to the Mexican coast earlier, had slowed down in forward speed, allowing the center to remain over warm water a little longer than forecast. This disturbance was upgraded to Tropical Depression EIGHT by the NHC at 1:30 P.M. and is now moving ashore. You can click on the map for information and graphics.
Good day everyone!
Purely crazy season! The NHC has declared GABRIELLE dissipated. Satellite imagery does indicate a recent flareup of convection over the area where the “center” would be located. Current vorticity maps indicate this may be trying to regenerate, as the recent analysis indicated approximately 70 units of positive vorticity at 850 mb, and 80 units at the 925 mb level. However, with the remnant having moved NW over the past 12 hours, it is in an area where upper level winds are not conducive for development. The upper level anticyclone remains in the south central Caribbean. Although not too likely, I will continue to monitor the area for any signs of regeneration, as upper level winds are forecast to become more conducive in about 24-30 hours.
Tropical Disturbance INVEST 99L had one of the best satellite image presentations about 2 hours ago, since it was declared. However, satellite loop imagery indicates this is moving ashore at the moment. Based on this, I am not expecting any further development of this disturbance. Residents in the area should be alert for flash flooding and mudslides due to heavy rainfall.
Tropical Disturbance INVEST 98L continues to move WNW in the EATL.
This disturbance is very disorganized. Two factors that seem to be inhibiting this are, albeit not much, there is some dry air intruding into the system, and upper level winds are marginal at the moment, with increasing shear. I will monitor this over the next 72 hours, as upper level winds may become conducive in about 60-72.
Elsewhere, a couple of tropical waves will be watched as they move off the west African continent over the next few days.
This season has been extremely strange. He we are approaching the climatological peak of the season, and we should be tracking 3 if not four developed storms, and should have an active wave train over Africa. However, satellite imagery shows basically NOTHING over the African Continent. I must say, at the moment, I’m puzzled at to what is causing this “drought”. I know one factor is we lost the MJO signal for quite a bit, and based on the current forecast for the MJO Multivariate Index, we may very well lose it again in about 5-7 days, and it is entering the Indian Ocean as of last update. In the longer range, models are split as to what happens with the MJO…the GFS members indicate the Index will move into the zero circle, then swing back around to OCTANT 8 in 2 weeks or so. The EUROPEAN members take it into OCTANTS 5 & 6.
Tropical Storm formation is not expected during the next 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)