Tropical Cyclone Discussion
Issued by NWS
WTNT41 KNHC 152033
HURRICANE EDOUARD DISCUSSION NUMBER 18
NWS NATIONAL HURRICANE CENTER MIAMI FL AL062014
500 PM AST MON SEP 15 2014
Edouard is approaching category 3 strength. The eye of the
hurricane has become circular this afternoon, and deep convection
has increased in the eyewall. Flight-level and SFMR winds, as well
as dropsonde data from two NOAA reconnaissance aircraft, indicate
that maximum winds are near 95 kt and the minimum pressure has
decreased to 963 mb. Radar images from one of the NOAA aircraft
indicate that the convective pattern is quite symmetric.
The hurricane could strengthen some more during the next day or so
while both the atmospheric and oceanic conditions remain favorable.
After that time, however, cooler water, drier air, and a notable
increase in shear should cause Edouard to weaken at a steady pace.
The cyclone is forecast to transition to a post-tropical cyclone by
day 4 when it is expected to be over very cold water and interacting
with a frontal zone. The NHC intensity forecast is at the high end
of the model guidance for the next 36 hours, and then follows the
intensity model consensus, IVCN.
Edouard continues to move northwestward but at a slightly slower
pace than earlier, 305/11 kt. Water vapor imagery and satellite-
derived winds indicate that the western side of the ridge that has
been steering the hurricane is eroding in response to a trough over
the western Atlantic. This change in the large-scale pattern
should cause Edouard to turn northward during the next 24 hours.
By late Tuesday and Wednesday, the system is expected to accelerate
northeastward and then eastward when it becomes embedded in the
mid-latitude westerlies. A slow down and a turn toward the
southeast is predicted by the end of the forecast period when the
weakening system is steered by the flow on the west side of a
deep-layer low over the northeast Atlantic. The NHC track forecast
has again been nudged to the left to come into better agreement with
the latest guidance.
FORECAST POSITIONS AND MAX WINDS
INIT 15/2100Z 28.0N 56.5W 95 KT 110 MPH
12H 16/0600Z 29.5N 57.3W 105 KT 120 MPH
24H 16/1800Z 31.6N 57.4W 105 KT 120 MPH
36H 17/0600Z 34.0N 55.7W 95 KT 110 MPH
48H 17/1800Z 36.8N 52.6W 85 KT 100 MPH
72H 18/1800Z 40.6N 43.3W 70 KT 80 MPH
96H 19/1800Z 40.5N 37.0W 50 KT 60 MPH...POST-TROPICAL
120H 20/1800Z 39.5N 33.5W 35 KT 40 MPH...POST-TROPICAL