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Tropical Storm Pilar Discussion Number   7
NWS National Hurricane Center Miami FL       EP192023
400 AM CDT Mon Oct 30 2023
 
There has been little change with Pilar overnight.  The storm is 
still producing a concentrated area of deep convection, but 
microwave data suggest that the low-level center is located near the 
southeastern edge of the thunderstorms.  The latest satellite 
intensity estimates range from 35 to 45 kt, but an ASCAT pass from a 
few hours ago showed maximum reliable winds closer to 30 kt.  Based 
on a blend of all of these data, the initial intensity is held at 35 
kt.

Pilar is moving slowly to the east-northeast, and that motion should 
continue for the next couple of days.  Nearly all of the models 
stall Pilar near the coast of Central America on Tuesday and Tuesday 
night, but at this point the reliable models keep the core of the 
storm offshore.  On Wednesday, Pilar will likely turn southwestward 
away from land as a mid-level ridge builds to the north of the 
system.  The cyclone will likely accelerate westward after that in 
part due to an anticipated Gulf of Tehuantepec gap wind event.  Only 
small changes were made to the previous NHC track forecast and this 
one lies fairly close to the consensus aids.

The storm will have an opportunity to strengthen during the next day 
or so as it remains over warm SSTs and in relatively favorable 
atmospheric conditions.  Pilar is expected to be near hurricane 
strength when it is close to the coast of Central America.  
However, beyond that time, the slow motion of the system could 
cause ocean upwelling and the Gulf of Tehuantepec gap wind event 
will likely result in an increase in shear and intrusions of dry 
and stable air.  Therefore, a weakening trend is forecast beginning 
late Tuesday or early Wednesday.  The NHC intensity forecast lies 
at the high end of the guidance in the short term, but falls closer 
to the middle of the guidance envelope from 72-120 hours.
 
Key Messages:
 
1. Heavy rains from Pilar will produce flash and urban flooding, 
along with mudslides in areas of higher terrain of the Pacific coast 
of Central America from El Salvador southward to Costa Rica through 
Wednesday.
 
2. Tropical storm conditions are possible beginning early Tuesday 
along portions of the Pacific coast of El Salvador, Honduras, and 
Nicaragua, where a Tropical Storm Watch remains in effect. 
Interests elsewhere along the Pacific coast of Guatemala,
and Nicaragua should monitor the progress of this system as
additional watches or warnings could be needed later today.
 
3. Swells generated by Pilar will begin to affect portions
of the Pacific coast of Central America later today.  These swells 
are likely to cause life-threatening surf and rip current 
conditions.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  30/0900Z 11.0N  91.8W   35 KT  40 MPH
 12H  30/1800Z 11.1N  91.2W   45 KT  50 MPH
 24H  31/0600Z 11.6N  90.1W   55 KT  65 MPH
 36H  31/1800Z 12.0N  89.5W   60 KT  70 MPH
 48H  01/0600Z 12.0N  89.2W   50 KT  60 MPH
 60H  01/1800Z 11.7N  89.7W   40 KT  45 MPH
 72H  02/0600Z 11.1N  91.2W   35 KT  40 MPH
 96H  03/0600Z  9.8N  95.3W   35 KT  40 MPH
120H  04/0600Z  9.3N 100.8W   35 KT  40 MPH
 
$$
Forecaster Cangialosi
 
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