Eastern Pacific Basin Tropical Cyclones

Hurricane Estelle Forecast Discussion


000
WTPZ41 KNHC 180242
TCDEP1

Hurricane Estelle Discussion Number  11
NWS National Hurricane Center Miami FL       EP062022
900 PM MDT Sun Jul 17 2022

Estelle's structure this evening is quite disheveled, with 
last-light visible satellite imagery suggesting that the low-level 
center was somewhat detached north from the deeper convective 
activity that is more aligned with the mid-level center. We finally 
received our first microwave imagery over Estelle in more than 24 
hours, an AMSR2 pass at 2013 UTC, which confirmed this structure, 
also indicating that the center had jogged a bit north of the 
previous forecast track. Subjective Dvorak satellite estimates at 
0000 UTC from TAFB and SAB were still 77 kt and 65 kt 
respectively, but both SATCON and ADT estimates have dropped from 
earlier today. The initial intensity this advisory is set at 70 kt 
as a compromise from all these various estimates.

Despite the earlier northward jog, Estelle remains on a general 
west-northwestward heading at 300/10 kt. A mid-level ridge is 
situated north of the cyclone, and is forecast to build-in further 
westward with time. The model guidance responds to this building 
ridge by maintaining Estelle on a similar heading, though with a 
short-term bend more westward and slight acceleration in the forward 
motion. The latest track forecast shows a similar evolution, though 
is on the north side of the guidance envelope early on, due to both 
the further north initial position, and the somewhat leftward bias 
observed in the track forecast over the past 24 hours. However, by 
the end of the forecast period, the current track forecast ends up 
located close to the multi-model consensus aid TVCE.

The intensity forecast is a bit problematic. Estelle appears to have 
ingested dry air into its inner-core today, possibly assisted by 
moderate northerly vertical wind shear under the typical 200-850 mb 
layer. This shear may be a result of the current misaligned low and 
mid-level centers. This inner-core structure also argues against 
rapid intensification in the short-term. However, SHIPS 
environmental variables still show Estelle remaining over 28C or 
warmer sea-surface temperatures (SSTs) over the next 24-36 hours 
while embedded in a fairly moist mid-level environment. Assuming the 
current dry-air near the core can be mixed out and the moderate 
shear does not import additional dry air, intensification still 
appears possible. The latest intensity forecast now indicates a more 
gradual intensification rate, assuming it will take a little time 
for the current core structure to recover. This intensity forecast 
is still somewhat higher than the majority of the guidance. After 
36 hours, Estelle will be crossing a sharp SST gradient, and be 
over sub 25C waters by 60 hours. Thus, weakening is anticipated and 
the latest forecast now makes Estelle post-tropical by 96 hours, 
which is a little faster than before. 

Estelle is expected to continue producing rough surf and rip current 
conditions along the coast of southwestern and west-central Mexico 
as well as the southern tip of the Baja California peninsula during 
the next several days.


FORECAST POSITIONS AND MAX WINDS

INIT  18/0300Z 16.8N 108.6W   70 KT  80 MPH
 12H  18/1200Z 17.2N 110.1W   75 KT  85 MPH
 24H  19/0000Z 17.7N 112.6W   80 KT  90 MPH
 36H  19/1200Z 18.1N 114.8W   85 KT 100 MPH
 48H  20/0000Z 18.9N 117.2W   80 KT  90 MPH
 60H  20/1200Z 19.8N 119.4W   70 KT  80 MPH
 72H  21/0000Z 20.8N 121.8W   55 KT  65 MPH
 96H  22/0000Z 22.0N 125.5W   35 KT  40 MPH...POST-TROPICAL
120H  23/0000Z 23.0N 129.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Papin



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