598 
WTPZ42 KNHC 050238
TCDEP2
 
Tropical Storm Lorena Discussion Number  13
NWS National Hurricane Center Miami FL       EP122025
800 PM PDT Thu Sep 04 2025
 
Lorena has not produced deep convection near its center since about 
8 AM this morning.  Waves of heavy showers and thunderstorms 
continue to stream northeastward across Baja California Sur, Sonora, 
and northern Sinaloa, but this activity cannot be directly linked 
to Lorena's circulation.  Weakening is assumed to have occurred 
since the earlier aircraft and ASCAT data, and the intensity is set 
at 40 kt based on a blend of Dvorak CI numbers and objective 
numbers (which are between 30 and 45 kt).  With Lorena over cool 
waters and southwesterly shear only expected to increase, deep 
convection is not forecast to redevelop, and Lorena is likely to 
become post-tropical Friday morning.  Winds will continue to 
steadily decrease, with the remnant low likely to dissipate by late 
Sunday.

Lorena has been moving west of the dynamical model guidance over 
the past 6 to 12 hours, and the best-performing track models since 
this morning have been the simple shallow Trajectory and Beta 
Advection (TABS) models.  Given that the circulation will remain 
shallow, the new NHC track forecast blends the TABS models with the 
latest GFS-ECWMF mean and HCCA consensus aid.  This puts the new 
forecast west of the previous prediction by a somewhat noticeable 
degree, showing more of a slow northwestward motion instead of 
northward trajectory.
 
Abundant moisture will continue to stream northeastward away from 
Lorena even though it is weakening.  Significant rainfall and flash 
flooding has already occurred over portions of Baja California Sur, 
and the risk of life-threatening flash flooding will continue across 
portions of Baja California Sur and Sonora through Friday, 
and southern Arizona and New Mexico through Saturday.
 
 
Key Messages:
 
1. Heavy rainfall associated with Lorena will continue to impact 
Baja California Sur and Sonora Mexico through Friday. This will 
increase the risk of life-threatening flash floods and mudslides 
across northwest Mexico.
 
2. Moisture from Lorena will contribute to heavy rainfall concerns 
across Arizona and New Mexico through Saturday. Isolated to 
scattered instances of flash flooding are possible across Arizona 
into Saturday.
 
3. Life-threatening surf and rip current conditions will affect
portions of the western coast of Baja California Sur through Friday.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  05/0300Z 24.6N 115.1W   40 KT  45 MPH
 12H  05/1200Z 25.0N 115.3W   30 KT  35 MPH...POST-TROP/REMNT LOW
 24H  06/0000Z 25.3N 115.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  06/1200Z 25.7N 115.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
 48H  07/0000Z 26.1N 116.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  07/1200Z 26.5N 117.6W   15 KT  15 MPH...POST-TROP/REMNT LOW
 72H  08/0000Z...DISSIPATED
 
$$
Forecaster Berg