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#1024848 (Received by flhurricane at: 3:51 PM 11.Nov.2020)
TCDAT5

Tropical Storm Theta Discussion Number 8
NWS National Hurricane Center Miami FL AL302020
900 PM GMT Wed Nov 11 2020

The deep convection associated with Theta has been trying to wrap
around the cyclone`s low-level center today, and the system consists
of a large curved band feature with clouds tops as cold as -65
degrees C. There was no complete sampling of the cyclone`s
circulation by the scatterometers today. However, a partial ASCAT-C
overpass this morning showed that 40-45 kt winds were occurring in
the eastern semicircle. This portion of the circulation has
previously been the weaker portion of Theta, which suggests some
higher winds could be occurring in the western semicircle.
Therefore, the initial intensity is being kept at a somewhat
uncertain 50 kt.

Theta appears to be holding its own in an environment of strong
southwesterly shear and over relatively cool water temperatures of
about 24 degrees C, within a favorable unstable atmosphere. The
cyclone will be traversing over progressively cooler waters over the
next couple of days, and the shear is expected to only abate
slightly. These somewhat counteracting factors should either allow
Theta to maintain its intensity or slowly weaken during that time.
Over the weekend, the upper-level winds are expected to increase
and shift out of the north, and force more stable air across the
cyclone. This should cause the convection to become displaced to the
south of the center and gradually dissipate. The GFS/CMC/ECMWF
simulated satellite imagery all indicate that the system should
degenerate to a remnant low by 96 h. The latest NHC intensity
forecast is similar to the previous one, and remains near the
various multimodel consensus aids.

The storm is moving east-northeastward at around 11 kt, steered by
mid-latitude westerlies to the north of a mid-level ridge. This
steering pattern is expected to remain in place for the next couple
of days. Model guidance is trending slower over the weekend, as they
are indicating that the ridge will weaken at around the same time
that the shear vector becomes northerly. This would cause the
cyclone to slow its forward motion and turn to the right, which is
now indicated in the official forecast. However, the latest NHC
track remains a little north of the consensus track guidance during
that time frame. By the end of the forecast period, an approaching
mid-latitude trough and associated front should pick up what remains
of Theta and begin to accelerate it to the northeast.


FORECAST POSITIONS AND MAX WINDS

INIT 11/2100Z 30.5N 31.9W 50 KT 60 MPH
12H 12/0600Z 31.1N 30.2W 50 KT 60 MPH
24H 12/1800Z 31.5N 27.8W 50 KT 60 MPH
36H 13/0600Z 31.9N 25.4W 45 KT 50 MPH
48H 13/1800Z 32.1N 23.5W 45 KT 50 MPH
60H 14/0600Z 32.0N 22.3W 45 KT 50 MPH
72H 14/1800Z 31.8N 21.3W 40 KT 45 MPH
96H 15/1800Z 31.7N 19.7W 30 KT 35 MPH...POST-TROP/REMNT LOW
120H 16/1800Z 35.1N 18.2W 30 KT 35 MPH...POST-TROP/REMNT LOW

$$
Forecaster Latto