ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
 
Tropical Depression Norbert Discussion Number  24
NWS National Hurricane Center Miami FL       EP192020
300 PM MDT Wed Oct 14 2020
 
Vertical wind shear and dry mid-level air are clearly taking a toll 
on Norbert. Infrared cloud top temperatures have rapidly warmed as 
Norbert has lost most, if not all, of its deep convection. Water 
vapor imagery shows a tongue of dry air drawn into the cyclone's 
circulation by a mid-level low pressure system centered to the west 
of Norbert. If current trends continue, Norbert could degenerate 
into a remnant low tonight or early Thursday. The advisory 
intensity is lowered to 30 kt based on a 1750Z ASCAT-B overpass 
that showed 25-30 kt winds in the northern semicircle of Norbert. 
This is consistent with T2.0 subjective Dvorak classifications from 
SAB and TAFB.

Norbert has moved a bit faster than was previously forecast, and 
its initial motion is estimated at 330/15 kt. The track guidance 
consensus depicts a northwestward motion with a decrease in forward 
speed through tonight as the depression moves between a mid-level 
ridge over northern Mexico and the aforementioned mid-level low. A 
slow northward turn is expected on Thursday. The NHC track forecast 
was adjusted slightly to the right of the previous forecast based 
on 12Z global model trends.

Norbert will continue weakening during the next day or so in an 
environment characterized by 20-25 kt of deep-layer shear, dry 
mid-level air, and low oceanic heat content. The official intensity 
forecast shows remnant low status at 24 h and dissipation at 36 h, 
which is consistent with the consensus of reliable global models.

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  14/2100Z 24.7N 114.9W   30 KT  35 MPH
 12H  15/0600Z 25.9N 115.7W   25 KT  30 MPH
 24H  15/1800Z 26.9N 115.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
 36H  16/0600Z...DISSIPATED
 
$$
Forecaster Reinhart/Beven
 
NNNN