Tropical Storm Beryl Discussion Number 31
NWS National Hurricane Center Miami FL AL022024
400 AM CDT Sat Jul 06 2024
Beryl's structure this morning is a shadow of its former self in the
Caribbean, with the low-level center partially exposed and displaced
south of the best mid-level rotation and deep convection. The final
couple of Air Force Hurricane Hunter fixes indicated the pressure
was rising, though the aircraft did also observe 850-mb flight level
winds of 65 kt, which still supports maintaining an initial
intensity of 50 kt. This value is between the Dvorak intensity
estimates provided by TAFB and SAB. Beryl's wind radii were adjusted
some from to a combination of aircraft, scatterometer, and synthetic
aperture radar wind data.
Beryl is currently estimated to be moving west-northwest at
300/10-kt. Soon, the tropical storm is expected to turn more
northwestward and gradually slow down as the steering currents
evolve due to both a weakness developing in the subtropical ridge to
the north, in addition to an upper-level low positioned west of
Beryl also imparting more poleward steering. After the significant
rightward shifts in the track guidance over the past day or so, the
latest cycle has come into better agreement very near the previous
NHC forecast track. In fact, the latest forecast track is very close
to the prior forecast, roughly between the latest GFS and ECMWF
forecasts. This track also splits the difference between the
reliable TVCN and HCCA consensus aids. However, it should be noted
that there still remains a fair amount of across-track spread in the
latest ECMWF ensemble guidance at the time Beryl is forecast to make
landfall in Texas on Monday.
The poor structure of the tropical storm this morning does not favor
much intensification in the short-term, and I suspect it will take
another day or so for convection to reorganize around the inner core
of Beryl. This process could also be slowed by a decent amount of
dry air in the southern Gulf of Mexico being imported into Beryl's
circulation by about 20 kt of southerly wind shear. However, this
wind shear decreases to under 10 kt per SHIPS guidance after 24
hours as Beryl moves into very warm 29-30 C sea-surface
temperatures. The upper-level low currently inducing the southerly
shear will also become positioned farther southwest of Beryl, in a
quadrant more favorable for TC intensification. Thus, strengthening
is expected to begin on Sunday with the rate of intensification
likely to increase in the final 24 hours before landfall, in
agreement with the most favorable conditions being prescribed by the
GFS and ECMWF models. The intensity forecast remains on the high
side of the guidance envelope, but is also similar to the prior
forecast and shows Beryl becoming a hurricane before reaching the
Texas coast on Monday.
It is important to note that the average NHC track error at 60 hours
is about 80 miles and the average intensity error is close to one
category. Users are reminded to consider these uncertainties when
using the forecast information.
Key Messages:
1. There is an increasing risk of damaging hurricane-force winds and
life-threatening storm surge in portions of northeastern Mexico and
the Texas Coast late Sunday into Monday, where Hurricane and Storm
Surge Watches are in effect. Additional watches and warnings may be
required later today. Interests in these areas should follow any
advice given by local officials.
2. Flash and urban flooding, some of which may be locally
considerable in nature, is likely across portions of the Texas Gulf
Coast and eastern Texas beginning late Sunday through midweek.
3. Rip currents will cause life-threatening beach conditions through
the weekend across much of the Gulf Coast. Beachgoers should heed
warning flags and the advice of lifeguards and local officials
before venturing into the water.
FORECAST POSITIONS AND MAX WINDS
INIT 06/0900Z 22.2N 91.3W 50 KT 60 MPH
12H 06/1800Z 23.3N 92.7W 50 KT 60 MPH
24H 07/0600Z 24.4N 94.3W 55 KT 65 MPH
36H 07/1800Z 25.6N 95.5W 60 KT 70 MPH
48H 08/0600Z 27.0N 96.4W 70 KT 80 MPH
60H 08/1800Z 28.5N 96.7W 80 KT 90 MPH...ON THE COAST
72H 09/0600Z 30.3N 96.5W 35 KT 40 MPH...INLAND
96H 10/0600Z 32.9N 94.0W 25 KT 30 MPH...POST-TROP/INLAND
120H 11/0600Z 35.5N 90.1W 20 KT 25 MPH...POST-TROP/INLAND
