ZCZC MIATCDEP1 ALL
TTAA00 KNHC DDHHMM
 
Tropical Storm Andres Discussion Number   5
NWS National Hurricane Center Miami FL       EP012021
300 AM MDT Mon May 10 2021
 
Andres remains a sheared tropical storm with a small ball of deep
convection displaced just east of the partially exposed low-level
center. All three scatterometer passes missed Andres. The initial
intensity remains 35 kt based on consensus subjective Dvorak
satellite intensity estimates of T2.5/35 kt from TAFB and SAB, and
objective intensity estimates of 37 kt and 35 kt from UW-CIMSS ADT
and SATCON, respectively.
 
The initial motion estimate is 325/04 kt. There are no significant
changes to the previous track forecast of reasoning. The latest NHC
track model guidance continues to show Andres moving slowly
northwestward around the western edge of a deep-layer subtropical
ridge while gradually weakening and becoming more vertically
shallow. The ridge to the north of the cyclone is forecast to
strengthen and build westward over the next few days, which is
expected to gradually nudge Andres west-northwestward on Tuesday and
westward on Wednesday. The new official track forecast is similar to
the previous advisory track, and remains along the southern edge of
the guidance envelope between the GFS and GFS-ensemble mean models,
and the HCCA and GFEX consensus track models.
 
Despite the ragged looking cloud pattern depicted in infrared
satellite imagery, night-viz and passive microwave satellite data
indicate that the low-level circulation has actually improved a
little since the previous advisory. However, the combination of
increasing southwesterly vertical wind shear and  entrainment of
drier and more stable low- to mid-level air from the west and
northwest is expected to induce gradual weakening later today.
Additional weakening is forecast on Tuesday and Wednesday as Andres
moves over cooler sea-surface temperatures, with the cyclone
expected to degenerate into a remnant low on Tuesday and dissipate
by Thursday. The latest NHC intensity forecast is essentially just
and update of the previous advisory, and closely follows a blend of
the IVCN and HCCA intensity consensus models.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 14.7N 109.1W   35 KT  40 MPH
 12H  10/1800Z 15.2N 109.7W   30 KT  35 MPH
 24H  11/0600Z 15.6N 110.3W   30 KT  35 MPH
 36H  11/1800Z 15.9N 111.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  12/0600Z 16.0N 112.2W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  12/1800Z 16.0N 113.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  13/0600Z...DISSIPATED
 
$$
Forecaster Stewart
 
NNNN