Tropical Storm KARINA
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TROPICAL STORM KARINA DISCUSSION NUMBER 25
NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014
800 PM PDT MON AUG 18 2014
Karina has continued to become better organized over the past few
hours. A convective cloud band wraps about 80 percent around the
circulation, and the Dvorak data T-number from TAFB is now 3.5 which
corresponds to an intensity estimate of 55 kt. The vertical shear
over the storm has decreased and is forecast to stay low for another
24-36 hours. Upper-level outflow has also increased over the
tropical cyclone. Therefore, Karina has an opportunity to intensify
some more and it could become a hurricane tomorrow as indicated by
the official forecast. Later in the forecast period, east-
northeasterly shear is predicted to increase, which should cause
gradual weakening. The official intensity forecast is close to the
SHIPS model guidance through 36 hours, and close to the intensity
model consensus thereafter.
The forward motion continues to slow and is now around 255/7 kt. A
mid-level ridge to the north of Karina should push the tropical
cyclone a little farther west over the next day or two. However the
westward steering is likely to end in a couple of days as Karina
becomes more influenced by the large circulation of Tropical
Storm Lowell passing to its northeast. By late in the forecast
period, a broad area of southwesterly low-level flow associated with
Lowell should start drawing Karina toward the northeast. The
official forecast takes the storm farther northeast late in the
period than the previous one, but not as much as some of our better
track guidance. The new NHC track forecast is in good agreement
with latest Florida State University Superensemble prediction.
FORECAST POSITIONS AND MAX WINDS
INIT 19/0300Z 15.9N 133.6W 55 KT 65 MPH
12H 19/1200Z 15.9N 134.3W 60 KT 70 MPH
24H 20/0000Z 15.9N 135.3W 65 KT 75 MPH
36H 20/1200Z 15.9N 136.0W 65 KT 75 MPH
48H 21/0000Z 16.0N 136.5W 60 KT 70 MPH
72H 22/0000Z 16.0N 136.5W 50 KT 60 MPH
96H 23/0000Z 16.6N 135.8W 45 KT 50 MPH
120H 24/0000Z 17.5N 134.5W 45 KT 50 MPH
$$
Forecaster Pasch
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