Tropical Cyclone Discussion

774
WTPZ42 KNHC 281440
TCDEP2
 
Tropical Storm Lowell Discussion Number   4
NWS National Hurricane Center Miami FL       EP122026
500 AM HST Fri Aug 28 2026
 
Northeasterly to easterly vertical wind shear continues to affect
Lowell, with the low-level center currently exposed to the northeast
of the deep convection. However, a recent burst of convection has 
developed closer to the center in the last hour or so. Objective 
satellite intensity estimates from UW-CIMSS range from 33 to 40 kt, 
and the latest subjective Dvorak classification from TAFB is 
T2.5/35 kt with a Current Intensity (CI) of 3.0/45 kt. Based on a 
blend of these estimates and recent satellite trends, the initial 
intensity is held at 40 kt.
 
The initial motion remains slowly east-northeastward. This slow
motion should continue through today, followed by a gradual turn
toward the west-northwest and west tonight into tomorrow as a
mid-level ridge begins to build to the north of the cyclone. As this
ridge strengthens, the system should gradually accelerate westward.
Beyond 48 to 72 hours, considerable along- and cross-track spread
remains in the model guidance. This uncertainty is tied to the
complex evolution of multiple systems and disturbances in the
central and eastern Pacific, and their subsequent impacts on the
steering flow. The latest NHC track forecast remains on the faster
side of the guidance envelope, generally blending the faster HCCA
and slightly slower TVCN consensus aids. The Google DeepMind model
is the fastest solution provided by the guidance, however as noted
in previous discussions, this model has exhibited a fast bias in the
Pacific basin this season.
 
Although Lowell is dealing with some moderate vertical wind shear, 
environmental conditions are expected to remain or become even more 
favorable for intensification over the next several days. The 
cyclone is forecast to move over warm sea surface temperatures 
within an environment of light to moderate shear and abundant 
mid-level moisture. Particularly beyond 60 hours, the intensity 
guidance indicates steady strengthening, and the system is forecast 
to reach hurricane intensity by this weekend. The updated NHC 
intensity forecast is similar to the previous advisory, lying near 
the high end of the guidance suite in the short term and closer to 
the middle of the envelope beyond 72 hours. However, it should be 
noted that some of the regional hurricane models, and HCCA suggest a 
faster rate of intensification is possible.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  28/1500Z 12.5N 132.8W   40 KT  45 MPH
 12H  29/0000Z 12.6N 133.1W   45 KT  50 MPH
 24H  29/1200Z 12.8N 134.3W   45 KT  50 MPH
 36H  30/0000Z 13.0N 135.6W   50 KT  60 MPH
 48H  30/1200Z 13.2N 137.5W   55 KT  65 MPH
 60H  31/0000Z 13.5N 139.1W   65 KT  75 MPH
 72H  31/1200Z 13.7N 140.9W   75 KT  85 MPH
 96H  01/1200Z 14.2N 144.2W   90 KT 105 MPH
120H  02/1200Z 14.6N 147.3W   95 KT 110 MPH