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Tropical Storm Beatriz Discussion Number 4
NWS National Hurricane Center Miami FL EP022023
400 PM CDT Thu Jun 29 2023
The cyclone's satellite presentation, at least in visible imagery,
has improved markedly through the day, and the low-level center had
become apparent in a relatively cloud-free region (which has
recently become obscured) surrounded by developing deep convection.
Dvorak satellite intensity estimates are T2.5/35 kt from TAFB and
T2.0/30 kt from SAB (with similar objective numbers), so the initial
intensity is raised to 35 kt, with the cyclone now designated as
Tropical Storm Beatriz.
Beatriz is moving toward the west-northwest, or 300/10 kt, along
the southern periphery of a mid-level ridge located over northern
Mexico. This ridge is forecast to weaken a bit during the next few
days, and Beatriz is therefore expected to move northwestward for
the next 4 days or so. The track guidance has continued to shift
to the right, closer to the coast of Mexico, and some models (in
particular the ECMWF and HCCA) bring the center inland in about
24-36 hours. The NHC track forecast has been shifted to the east as
well, and now shows the center of Beatriz grazing the coasts of
Michoacan, Colima, and Jalisco in the next 24-48 hours. It is
important to remember that Beatriz's oblique angle of approach to
the southwestern coast of Mexico makes it difficult to know exactly
where the center might come onshore, if at all, and therefore a
larger-than-normal part of the coastline is at risk of some effects
from the storm.
Beatriz is now expected to rapidly intensify during the next 24
hours in an environment of low shear and abundant moisture, and
over very warm waters of 30-31 degrees Celsius. Following the
trend from this morning, the intensity guidance shows significant
strengthening in the short term, and the NHC intensity forecast has
been raised to the high end of the guidance, closest to the HAFS-A
and HCCA solutions at 24 hours. After that time, Beatriz's
intensity will largely depend on if the center reaches land. Based
on the official track forecast's proximity to land, intensification
is shown through 36 hours, with weakening thereafter. Faster
weakening is anticipated near the end of the forecast period due to
drier air and cooler sea surface temperatures, and global model
guidance suggests that Beatriz could degenerate into a remnant low
by day 5, if not sooner.
KEY MESSAGES:
1. Beatriz is forecast to rapidly intensify and become a hurricane
on Friday, bringing a risk of hurricane-force winds and a dangerous
storm surge to portions of the southwestern coast of Mexico during
the next couple of days. A Hurricane Warning is now in effect for
portions of the coasts of Guerrero, Michoacan, Colima, and Jalisco,
and hurricane conditions are expected somewhere in those areas
Friday and Saturday.
2. Locally heavy rainfall is expected across southern Mexico from
the state of Oaxaca westward to the state of Jalisco. These rains
could lead to life-threatening flash flooding and mudslides.
FORECAST POSITIONS AND MAX WINDS
INIT 29/2100Z 15.0N 99.4W 35 KT 40 MPH
12H 30/0600Z 15.9N 100.7W 50 KT 60 MPH
24H 30/1800Z 17.2N 102.4W 65 KT 75 MPH
36H 01/0600Z 18.7N 104.1W 70 KT 80 MPH
48H 01/1800Z 20.0N 105.7W 60 KT 70 MPH
60H 02/0600Z 20.8N 106.7W 55 KT 65 MPH
72H 02/1800Z 21.6N 107.6W 45 KT 50 MPH
96H 03/1800Z 22.5N 109.1W 35 KT 40 MPH
120H 04/1800Z 23.5N 111.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
$$
Forecaster Berg
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