ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM
 
Hurricane Douglas Discussion Number  14
NWS National Hurricane Center Miami FL       EP082020
1100 AM HST Thu Jul 23 2020
 
Visible satellite images show that Douglas is quite a powerful 
hurricane.  The eye has become more crisp during the day, and 
infrared data also show that the eyewall convection has deepened.  
The initial wind speed is raised to 110 kt, which matches a blend of 
the latest TAFB/SAB Dvorak estimates.  Douglas is beginning to move 
across the typical cool SST gradient of the eastern Pacific, 
implying that the hurricane is probably near its peak intensity.  
The cyclone should only slowly weaken on Friday and Saturday due to 
cooler waters along the predicted track and the vertical shear 
remaining low.  As the hurricane approaches the Hawaiian Islands on 
Sunday, the SSTs increase but so does the shear. Since the shear 
generally dominates over marginally warm waters, a continued 
weakening is forecast.  However, almost all of the guidance shows 
Douglas near hurricane strength as it moves close to Hawaii.  
The model guidance remains consistent, and no significant changes 
were made to the NHC wind speed prediction.
 
Douglas continues moving fairly quickly toward the west-northwest. A 
large mid-level ridge over the eastern and central Pacific should 
continue to steer the hurricane on this general course and speed for 
the next couple of days, with some deceleration and a westward turn 
by late in the weekend.  The guidance is a little more divergent 
than the previous cycle, with a subtle northward model trend at 
longer range due to a weaker ridge forecast north of Hawaii, though 
the ECMWF and its ensembles have shifted a little southward.  Given 
these mixed signals in the guidance, very little change is made to 
the previous NHC track forecast, and the new official forecast lies 
on the southwest side of the model envelope.

Key Messages:
 
1.  Douglas is expected to move near or over portions of the
Hawaiian Islands this weekend, and there is an increasing chance
that strong winds, dangerous surf, and heavy rainfall could affect
portions of the state beginning on Sunday.  Interests on the
Hawaiian Islands should continue to monitor the progress of Douglas
and the official forecasts as they evolve over the next few days. 
Watches could be issued on Friday.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  23/2100Z 14.1N 137.3W  110 KT 125 MPH
 12H  24/0600Z 15.0N 139.7W  110 KT 125 MPH
 24H  24/1800Z 16.2N 142.8W  100 KT 115 MPH
 36H  25/0600Z 17.4N 145.9W   90 KT 105 MPH
 48H  25/1800Z 18.5N 149.0W   80 KT  90 MPH
 60H  26/0600Z 19.4N 152.0W   70 KT  80 MPH
 72H  26/1800Z 20.1N 154.9W   65 KT  75 MPH...NEAR HAWAII
 96H  27/1800Z 21.0N 160.5W   55 KT  65 MPH
120H  28/1800Z 21.5N 167.0W   45 KT  50 MPH
 
$$
Forecaster Blake
 
NNNN