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Tropical Storm Blas Discussion Number 16
NWS National Hurricane Center Miami FL EP022022
900 PM MDT Fri Jun 17 2022
Blas has fallen apart tonight. The mid-level center of the cyclone
has sheared off to the southwest, with no deep convection near the
surface center, and a mostly-exposed low-level center was visible
on the last few daylight satellite images. Dvorak classifications
are basically dropping as fast as the rules allow, and given the
lack of any significant thunderstorm activity, the initial wind
speed is set on the low end of the estimates to 60 kt.
Continued weakening is anticipated due to Blas moving over cool
waters, although the loss of strength could be tempered by
decreasing wind shear as well. The storm should produce a few more
rounds of deep convection in the marginally unstable environment
before eventually becoming a remnant low early next week. Model
guidance is in good agreement on this solution, and the only modest
change to the forecast was lowering it in the near-term due to the
initial intensity. Additionally, the timing of Blas becoming a
post-tropical cyclone was moved up by 12 h in this forecast cycle,
and since most of the guidance indicate Blas should decay into a
trough around 120 h, the NHC forecast does as well.
Blas has slowed considerably during the past several hours,
probably due to the vortex decoupling, with an initial motion
estimate of 290/6 kt. A slow westward to west-northwestward motion
is expected during the next several days due to the system
weakening and becoming increasingly steered by the lighter
low-level flow. The latest NHC track forecast is basically an
update of the previous one, shifted a bit to the north to come into
better agreement with the model consensus aids.
While Blas is moving farther away from the coast of Mexico, its
associated swells are expected to continue to affect portions of the
coast of southwestern Mexico and the southern Baja California
peninsula for another day or two. These conditions are likely to
cause dangerous surf and rip currents in those areas.
FORECAST POSITIONS AND MAX WINDS
INIT 18/0300Z 17.6N 110.2W 60 KT 70 MPH
12H 18/1200Z 18.0N 111.3W 55 KT 65 MPH
24H 19/0000Z 18.3N 112.5W 50 KT 60 MPH
36H 19/1200Z 18.4N 113.4W 45 KT 50 MPH
48H 20/0000Z 18.4N 114.2W 40 KT 45 MPH
60H 20/1200Z 18.4N 115.2W 35 KT 40 MPH...POST-TROPICAL
72H 21/0000Z 18.5N 116.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 22/0000Z 19.0N 118.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 23/0000Z...DISSIPATED
$$
Forecaster Blake
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