Eastern Pacific Basin Tropical Cyclones

Tropical Storm Julia Forecast Discussion


000
WTPZ43 KNHC 092037
TCDEP3

Tropical Storm Julia Discussion Number  14
NWS National Hurricane Center Miami FL       EP182022
400 PM CDT Sun Oct 09 2022

Julia's center has raced across Nicaragua all day and is just about 
ready to emerge over the eastern Pacific waters.  Low-topped 
convection continues near the center, and the circulation remains 
well defined in visible satellite imagery, radar data from Managua, 
and surface observations from Nicaragua.  Some deeper convection 
continues to form in a band over eastern Nicaragua and over the 
adjacent Pacific waters.  Based on a typical decay rate of a 
tropical cyclone's winds over land, the initial intensity is 
estimated to be 45 kt.

Even though Julia has made it across Nicaragua intact as a tropical 
cyclone, the interaction with land has still taken a toll.  
Moderate deep-layer shear out of the east-northeast has also begun 
to affect the cyclone, and forecast wind fields from the GFS, 
ECMWF, and UKMET all show the circulation shrinking over the next 
day or so.  Using these models as the basis for the intensity 
forecast, continued weakening is anticipated, and Julia is likely to 
fall below tropical storm strength in 12 to 24 hours.  The cyclone 
is then expected to dissipate by 36 hours when it becomes absorbed 
by a broader surface trough farther west associated with an ongoing 
Gulf of Tehuantepec gap wind event.

Julia's fast westward motion has continued, but it's reaching the 
western end of the subtropical ridge and should turn toward the 
west-northwest and slow down a bit over the next 24 hours.  The NHC 
track forecast lies on the northern side of the model trackers and 
closely follows the raw wind and pressure fields from the GFS, 
ECMWF, and UKMET models, moving Julia very close to and parallel to 
the Pacific coasts of Honduras, El Salvador, and Guatemala before 
dissipation.  Most of the model trackers are not valid in this 
case since they are attached to the aforementioned broader area of 
vorticity to the west and not Julia itself.


Key Messages:

1. Julia is forecast to move over the far eastern Pacific waters 
as a tropical storm through early Monday near the coasts of 
Nicaragua, Honduras, and El Salvador, where tropical storm warnings 
are in effect.  Tropical-force-winds are also possible on Monday 
along the Pacific coast of Guatemala, where a tropical storm watch 
is in effect.

2. Life-threatening flash flooding and mudslides are expected across 
portions of Central America tonight and Monday.  Flash flooding is 
anticipated across the Isthmus of Tehuantepec in Mexico early this 
week.


FORECAST POSITIONS AND MAX WINDS

INIT  09/2100Z 12.4N  86.9W   45 KT  50 MPH...NEAR THE NIC. COAST
 12H  10/0600Z 12.8N  88.7W   35 KT  40 MPH...OVER WATER
 24H  10/1800Z 13.6N  90.7W   25 KT  30 MPH
 36H  11/0600Z...DISSIPATED

$$
Forecaster Berg



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