Oct 15, 2014
Hurricane Gonzalo Strengthens to Category 4
Hurricane Gonzalo becomes the first Category 4 hurricane in the Atlantic basin since Ophelia in 2011. Gonzalo should turn northward by early Thursday and north-northeastward Thursday night and Friday, likely bringing Gonzalo near Bermuda in about two days. This image was taken by GOES West at 1200Z on October 15, 2014.
000
WTNT43 KNHC 152045
TCDAT3
HURRICANE GONZALO DISCUSSION NUMBER 14
NWS NATIONAL HURRICANE CENTER MIAMI FL AL082014
500 PM AST WED OCT 15 2014
Gonzalo is not quite as well organized as it was this morning.
Satellite images show that the eye of the hurricane appears less
distinct than it was earlier today, and radar images from a NOAA
hurricane hunter aircraft earlier today suggested than the inner
eyewall could be eroding. The initial wind speed is lowered
to 110 kt based on the slightly degraded appearance of the
storm. Another Air Force reconnaissance aircraft is scheduled to
investigate Gonzalo this evening and should provide a better
assessment of its intensity and structure.
The hurricane remains on track and is moving northwestward at about
9 kt. Water vapor images show a large trough over the eastern
United States. This trough is expected to move eastward during the
next couple of days, which should cause Gonzalo to make a turn
toward the north on Thursday and north-northeast on Friday, likely
bringing Gonzalo near Bermuda in about 2 days. After that time, a
faster northeastward and then east-northeastward motion is
predicted over the North Atlantic Ocean. The track model guidance,
in general, is a little slower than it was at 1200 UTC and the
official forecast has been adjusted accordingly. The guidance is
also not quite as tightly clustered as it has been, as the ECMWF
has shifted a bit west of the rest of the primary objective aids.
The large scale environmental conditions are expected to remain
favorable during the next day or so, and the intensity of Gonzalo
will likely fluctuate due to eyewall replacement cycles. In
about 48 hours, the hurricane is expected to be moving into an
atmosphere of increasing southwesterly shear and drier air, and over
sharply colder waters. These conditions should cause weakening and
post-tropical transition in 3 to 4 days.
NOAA buoy 41046 recently reported a pressure of 955 mb, and was
quite useful in estimating Gonzalo's minimum pressure.
FORECAST POSITIONS AND MAX WINDS
INIT 15/2100Z 24.1N 68.6W 110 KT 125 MPH
12H 16/0600Z 25.3N 68.9W 110 KT 125 MPH
24H 16/1800Z 27.2N 68.6W 105 KT 120 MPH
36H 17/0600Z 29.7N 67.2W 105 KT 120 MPH
48H 17/1800Z 32.9N 65.3W 100 KT 115 MPH
72H 18/1800Z 41.8N 58.4W 80 KT 90 MPH
96H 19/1800Z 51.0N 42.0W 55 KT 65 MPH...POST-TROP/EXTRATROP
120H 20/1800Z 54.0N 20.0W 40 KT 45 MPH...POST-TROP/EXTRATROP
$$
Forecaster Cangialosi