ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
Tropical Storm Aletta Discussion Number 19
NWS National Hurricane Center Miami FL EP022018
300 AM MDT Sun Jun 10 2018
After being devoid of thunderstorms for some time, a burst of
deep convection developed over the northern semicircle of Aletta.
This has probably made the weakening of the cyclone a little less
rapid than had been occurring over the last day or so. The current
intensity estimate is down to 45 kt based on a blend of subjective
Dvorak estimates from TAFB and SAB along with objective Dvorak
estimates from UW-CIMSS. In spite of the recent increase of
thunderstorm activity, which is thought to be temporary, strong
shear and marginal SSTs are likely to cause continued weakening and
Aletta is expected to degenerate into a remnant low in a day or so.
This is consistent with the intensity model consensus.
The system continues to move slowly westward, or around 280/5 kt.
A weak low- to mid-level ridge to the north of Aletta should
maintain this general motion for a few days. Later in the period,
steering currents are forecast to become very weak, and little
motion is indicated at days 4 and 5. By that time, however,
Aletta should be a very weak post-tropical cyclone. The official
forecast is similar to the previous one and on the southern side of
the track model guidance suite.
FORECAST POSITIONS AND MAX WINDS
INIT 10/0900Z 16.0N 114.5W 45 KT 50 MPH
12H 10/1800Z 16.1N 115.5W 35 KT 40 MPH
24H 11/0600Z 16.1N 116.8W 30 KT 35 MPH
36H 11/1800Z 16.0N 117.9W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 12/0600Z 15.9N 119.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 13/0600Z 15.8N 120.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 14/0600Z 15.6N 121.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 15/0600Z 15.4N 121.2W 15 KT 15 MPH...POST-TROP/REMNT LOW