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Tropical Storm Nora Discussion Number  18
NWS National Hurricane Center Miami FL       EP142021
900 PM MDT Sun Aug 29 2021
 
Nora appears to have moved inland, and it is unclear if it still has
a well-defined surface center. Earlier microwave data was
inconclusive regarding the existence of the low level center, while
the Dvorak analysts from TAFB and SAB were each unable to fix Nora's
center over water. The intensity has been lowered to 35 kt, assuming
weakening has occurred due to continued interaction with land.
Baring an unexpected redevelopment of the center over water, Nora
should continue to weaken inland, and could dissipate as soon as 
early Monday. Quick dissipation is now supported by all of the 
dynamical guidance. Accordingly, the NHC intensity forecast has 
been adjusted much lower than in the previous advisory. Nora 
is forecast to become post-tropical tomorrow and dissipate by 
Tuesday. Based on recent trends, this forecast is probably generous.
 
Despite the uncertainty associated with Nora's position, the system
still appears to be moving generally north-northwestward, with an 
initial motion of 330/10 kt. None of the dynamical guidance is able 
to track a low-level center more than about 24 h. However,there is 
good agreement that the mid-level remnants of Nora will continue 
moving generally northwestward and could contribute to heavy rain 
across northwest Mexico and portions of the southwestern U.S. during 
the middle to latter portion of the week.
 
Key Messages:
 
1. Heavy rain associated with Nora is expected across the west
coast of Mexico from the states of Nayarit northward to southern
Sonora.  This rain will likely result in life-threatening flash
flooding and mudslides across these regions. Rainfall from Nora is
likely to spread into the southwestern U.S. and central Rockies
during the middle to latter portion of the week, bringing the
potential for flash flooding to the region
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/0300Z 24.8N 107.9W   35 KT  40 MPH
 12H  30/1200Z 25.4N 108.4W   35 KT  40 MPH...INLAND
 24H  31/0000Z 26.3N 109.1W   30 KT  35 MPH...POST-TROP/INLAND
 36H  31/1200Z 27.0N 109.6W   25 KT  30 MPH...POST-TROP/INLAND
 48H  01/0000Z...DISSIPATED
 
$$
Forecaster D. Zelinsky
 
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