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HURRICANE MARIE DISCUSSION NUMBER 18
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132014
200 AM PDT TUE AUG 26 2014
Microwave images indicate that Marie still has a double eyewall
structure, though the outer eyewall is open on the north side.
The eye of the hurricane remains fairly distinct in satellite
images, but deep convection is not as intense as it was earlier.
The initial intensity is lowered to 90 kt, following the Dvorak
CI-numbers from TAFB and SAB. An ASCAT pass around 0500 UTC
indicated that despite the weakening, the wind field of Marie
remains very large.
The hurricane is moving across a sharp sea surface temperature
gradient, and it is expected to cross the 26 degree C isotherm later
today. These cold waters, combined with a drier and more stable air
mass, should cause Marie to continue weakening at a steady pace. The
NHC intensity forecast is an update of the previous one and shows
Marie becoming a post-tropical cyclone by 72 hours when it is
expected to be over water temperatures below 23 C.
Marie is moving northwestward at 12 kt. A west-northwestward to
northwestward motion at about the same forward speed is forecast
during the next few days while the system remains steered by
mid-level ridging to its northeast. A slow down and turn toward
the north-northwest is expected by the end of the forecast period
when the weak system is steered by the lighter low-level flow. The
NHC track forecast is nudged to the south this cycle, toward the
latest consensus aids.
Very large southerly swells continue to affect much of the Baja
California peninsula, and will soon reach the southern California
coast. These swells are expected to persist for a couple of days,
and could produce life-threatening surf and rip currents, as well as
minor coastal flooding.
FORECAST POSITIONS AND MAX WINDS
INIT 26/0900Z 19.9N 117.8W 90 KT 105 MPH
12H 26/1800Z 20.9N 119.5W 75 KT 85 MPH
24H 27/0600Z 21.9N 121.8W 60 KT 70 MPH
36H 27/1800Z 22.9N 124.4W 50 KT 60 MPH
48H 28/0600Z 24.2N 126.8W 40 KT 45 MPH
72H 29/0600Z 27.3N 130.8W 35 KT 40 MPH...POST-TROPICAL
96H 30/0600Z 29.9N 132.6W 30 KT 35 MPH...POST-TROP/REMNT LOW
120H 31/0600Z 30.5N 133.2W 25 KT 30 MPH...POST-TROP/REMNT LOW