Advisories

000
WTPZ42 KNHC 290233
TCDEP2
 
Hurricane Genevieve Discussion Number  20
NWS National Hurricane Center Miami FL       EP072026
500 PM HST Tue Jul 28 2026
 
Genevieve's satellite presentation has continued to oscillate this 
afternoon and evening, with deep cold convection wrapping around a 
cloud-filled eye with occasional lightning. A GPM microwave pass 
showed that the western eyewall had started to erode. Over the last 
few hours, there have been occasional breaks within the inner core, 
but the inner core has been resilient and has continued to wrap deep 
convection. Objective intensity estimates from UW-CIMSS remain 
around 105118 kt, which prompted the special advisory a few hours 
ago. Using these estimates, the initial intensity is held at 115 kt 
for this advisory.
 
The hurricane will remain in a marginal environment over the next 24 
hours, characterized by low-to-moderate vertical wind shear, sea 
surface temperatures near 2728C, and mid-level relative humidity 
values in the 50 to 60 percent range. Changes in convective 
organization and inner core dynamics will allow for short-term 
intensity fluctuations over the next day or so. Gradual weakening is 
forecast through 24 hours, followed by a faster rate of decay once 
the system crosses the 26C isotherm in 2436 hours. As the cyclone 
traverses cooler waters, decreasing mid-level relative humidity will 
further suppress deep convection. The official NHC intensity 
forecast lies near the upper end of the guidance suite in the short 
term, reflecting recent intensity adjustments, and aligns closely 
with the consensus aids from 48 hours through the end of the 
forecast period. The timing of post-tropical transition has been 
moved up to Day 4, consistent with model simulated satellite imagery 
from the latest GFS and ECMWF.

Genevieve is moving west-northwestward at an estimated motion of 
290/8 kt along the southwestern periphery of a ridge centered to the 
northwest of the system. A slightly faster forward speed is 
anticipated during the next few days as the ridge expands westward. 
The NHC track forecast was shifted slightly to the left, and lies 
closest to the HCCA corrected consensus aid.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  29/0300Z 18.3N 117.6W  115 KT 130 MPH
 12H  29/1200Z 18.6N 118.9W  115 KT 130 MPH
 24H  30/0000Z 19.3N 120.8W  105 KT 120 MPH
 36H  30/1200Z 20.0N 123.2W   90 KT 105 MPH
 48H  31/0000Z 20.7N 125.6W   75 KT  85 MPH
 60H  31/1200Z 21.5N 128.0W   60 KT  70 MPH
 72H  01/0000Z 22.2N 130.7W   50 KT  60 MPH
 96H  02/0000Z 23.7N 136.4W   40 KT  45 MPH...POST-TROPICAL
120H  03/0000Z 25.5N 141.7W   35 KT  40 MPH...POST-TROPICAL
 
$$
Forecaster Kelly