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Tropical Storm Lidia Discussion Number  25
NWS National Hurricane Center Miami FL       EP152023
300 AM MDT Mon Oct 09 2023
 
Lidia's convective structure has improved during the last several 
hours with deep bursts of convection, and cold cloud tops near -90 
degrees Celsius at times. The low-level center has become embedded 
beneath this recent burst as well. There is a fairly large range of 
intensity estimates this advisory cycle, however. Subjective Dvorak 
satellite final-T intensity estimates are a T4.0/ 65 kts, from both 
TAFB and SAB. Objective satellite estimates from UW-CIMSS ADT and 
AiDT are 51 kt and 61 kt, respectively. An ASCAT-B pass from a few 
hours ago depicted a much weaker wind field around 35 kt, although 
the convective pattern has markedly improved since that time. Using 
a blend of these data, the initial intensity is set to an uncertain 
55 kt for this advisory. The Air Force Hurricane Hunters are 
scheduled to investigate the system later this afternoon, which will 
provide valuable in-situ data to bring clarity to Lidia's intensity.
 
Vertical wind shear over the system is forecast to relax over the 
next 24-36 hr while Lidia moves over warm sea surface temperatures 
on its approach to west-central Mexico.  Models are in fairly good 
agreement with this strengthening scenario, and Lidia is forecast 
to become a hurricane late today, with the peak intensity unchanged 
from the previous advisory of 85 kt when the system is near the 
coast of Mexico. The NHC intensity forecast lies near the HFIP 
corrected consensus model, on the higher side of the guidance. 
After Lidia makes landfall, rapid weakening is expected given the 
high terrain, and the system is now forecast to dissipate by 60 h.
 
Lidia is moving north-northeastward or 020 degrees at 4 kt.  A 
faster motion to the northeast and east-northeast is expected later 
today and Tuesday as a mid- to upper-level trough approaches the 
system. The track guidance has shifted slightly south this 
cycle, with still some along-track timing differences with the GFS 
being the fastest.  The NHC track forecast has been nudged 
southward and lies near the various consensus aids.
 
 
Key Messages:
 
1. Lidia is expected to strengthen before it reaches west-central 
Mexico, and hurricane conditions are expected within the Hurricane 
Warning area on Tuesday, and hurricane and tropical storm 
conditions are possible in the watch areas beginning Tuesday.
 
2. Heavy rains from Lidia will likely produce flash and urban
flooding, along with possible mudslides in areas of higher terrain
across the the state of Nayarit, southern portions of the state of
Sinaloa, and coastal portions of the state of Jalisco in western
Mexico.
 
3. A dangerous storm surge is expected near and to the south where
the center of Lidia moves over the Islas Marias and the coast of
west-central Mexico.
 
4. Swells from Lidia will cause dangerous surf and rip current
conditions along the west coast of Mexico and the Baja California
peninsula during the next few days.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/0900Z 18.2N 112.4W   55 KT  65 MPH
 12H  09/1800Z 18.7N 111.6W   60 KT  70 MPH
 24H  10/0600Z 19.4N 109.7W   70 KT  80 MPH
 36H  10/1800Z 20.7N 107.2W   85 KT 100 MPH
 48H  11/0600Z 22.6N 104.4W   40 KT  45 MPH...INLAND
 60H  11/1800Z...DISSIPATED
 
$$
Forecaster Kelly
 
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