SUMMARY OF 1100 AM HST...2100 UTC...INFORMATION
-----------------------------------------------
LOCATION...19.3N 149.4W
ABOUT 370 MI...600 KM E OF HILO HAWAII
ABOUT 565 MI...915 KM ESE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...967 MB...28.56 INCHES
1100 AM HST TUE AUG 30 2016
The satellite presentation of Madeline showed a brief improvement
this morning but has since degraded in the presence of increasing
vertical wind shear. An Air Force Reconnaissance aircraft has made
several helpful passes through the hurricane this morning. Maximum
flight level winds of 100 kt were recorded in the northeast quadrant,
though a peak SFMR observation of 115 kt was reported.
Given the minimum pressure reports from the aircraft and the range of
the data, the current intensity is lowered to 100 kt.
The initial motion for this advisory is 270/09 kt. Madeline is
moving westward along the southern edge of a low to mid level
ridge, while a shallow upper level trough continues to dig toward
the hurricane from the northwest. The ridge will keep Madeline on
a westward-moving track today, followed by a gradual turn toward
the west-southwest tonight and Wednesday as the ridge to the
north builds and the upper level trough imparts northerly winds in
the high levels of the cyclone. This track will take the center
of Madeline dangerously close to the Big Island of Hawaii
late Wednesday and Thursday. Given its close approach and
uncertainty in the track forecast, a Hurricane Warning has been
issued for the Big Island of Hawaii. Late Thursday and Friday
Madeline is forecast to turn back toward the west-northwest as the
upper level trough digs southward over Hawaii. The forecast track is
essentially an update of the prior advisory and is slightly north of
the middle of the guidance envelope. The notable northern outlier
continues to be the GFDL.
As the upper level trough digs southward, vertical wind shear
is expected to induce slow weakening of Madeline through the
next five days. UW CIMSS estimates current vertical wind shear from
the west-southwest at 13 kt, and SHIPS forecasts shear to gradually
increase during the next 24 to 36 hours. The intensity forecast is
similar to the prior advisory package, and the rate of weakening is
slightly slower than IVCN. It is worth noting that SHIPS weakens
the system at a faster rate. Although it will be weakening, Madeline
is expected to remain a dangerous hurricane as it passes near the
Big Island of Hawaii late Wednesday into early Thursday.
Users are reminded to not focus too closely on the exact forecast
track, as small changes can lead to differences in impacts and that
hazards associated with hurricanes can extend well away from the
center.
FORECAST POSITIONS AND MAX WINDS
INIT 30/2100Z 19.3N 149.4W 100 KT 115 MPH
12H 31/0600Z 19.2N 150.9W 95 KT 110 MPH
24H 31/1800Z 18.9N 152.8W 90 KT 105 MPH
36H 01/0600Z 18.6N 154.9W 80 KT 90 MPH
48H 01/1800Z 18.2N 157.2W 70 KT 80 MPH
72H 02/1800Z 18.3N 161.3W 60 KT 70 MPH
96H 03/1800Z 18.8N 167.1W 55 KT 65 MPH
120H 04/1800Z 19.5N 172.8W 50 KT 60 MPH
