ZCZC HFOTCDCP2 ALL
TTAA00 PHFO DDHHMM
Hurricane Douglas Discussion Number 28
NWS Central Pacific Hurricane Center Honolulu HI EP082020
1100 PM HST Sun Jul 26 2020
Hurricane Hunters from the Air Force's 53rd Weather Reconnaissance
Squadron have again been flying around and through Douglas since
sunset this evening, and have found the cyclone to be a little
stronger than earlier today. Maximum flight level winds were
between 90 and 100 kt, with a peak of 103 kt recently reported. Peak
SFMR winds ranged from 75 to 85 kt, while the central pressure has
been pretty steady, and close to the value used in the previous
advisory. Based on the preponderance of evidence, the initial
intensity for this advisory was conservatively increased to 80 kt.
This indicates a slight strengthening trend, despite what appears to
be a hostile environment characterized by southerly vertical wind
shear.
The initial motion estimate is 290/14 kt, with Douglas primarily
being steered by a low- to mid-level ridge centered to the north of
the cyclone. In the upper levels, Douglas lies between a ridge to
the east and a trough to the west, in an environment characterized
by southerly vertical wind shear. The expectation is that this
debilitating wind shear will persist over the cyclone over the next
couple of days, leading to de-coupling of the lower and upper
levels of the cyclone, and subsequent weakening. The increasingly
shallow system is then expected to be steered toward the west at an
increased forward speed until dissipation occurs in a couple of
days. The updated track forecast is close to a fairly tightly
clustered suite of dynamical model guidance. The intensity
forecast also leans more heavily on the dynamical models, and
anticipates a fairly rapid rate of weakening west of the main
Hawaiian Islands.
Key Messages
1. Douglas will pass just north of Kauai tonight, producing locally
strong and potentially damaging winds, flooding rainfall, and
dangerously high surf, especially along north and east facing
shores. Terrain effects can cause strong localized acceleration of
the wind through gaps and where winds blow downslope.
FORECAST POSITIONS AND MAX WINDS
INIT 27/0900Z 22.5N 158.8W 80 KT 90 MPH
12H 27/1800Z 23.2N 161.5W 70 KT 80 MPH
24H 28/0600Z 23.7N 165.0W 60 KT 70 MPH
36H 28/1800Z 24.1N 168.5W 50 KT 60 MPH
48H 29/0600Z 24.3N 172.0W 40 KT 45 MPH
60H 29/1800Z 24.5N 175.8W 35 KT 40 MPH
72H 30/0600Z 25.0N 179.5W 30 KT 35 MPH
96H 31/0600Z 26.5N 173.0E 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 01/0600Z...DISSIPATED
$$
Forecaster Birchard
NNNN