As of Now Bertha continues to be forecasted to remain well East of the US mainland. By Monday afternoon we should know if Bertha has turned on schedule or if she is going to confuse everyone.
Last Updated 8/2/2014, 5:00:00 PM (Eastern Standard Time)
Location 18.4N 68.5W Movement WNW at 22 mph
Wind 45 MPH Pressure: 1010 MB
Bertha has maintained some organized convection over the eastern
semicircle during the past several hours. However, the system
barely qualifies as a tropical cyclone, as a combination of NOAA
hurricane hunter aircraft and surface data cannot definitively close
off the circulation. The initial intensity is reduced to 40 kt
based on a combination of surface observations and data from the San
Juan WSR-88D Doppler radar. It should be noted that Bertha
continues to suffer from dry air entrainment and northwesterly
vertical shear, and advisories could be discontinued tonight or
Sunday if the system becomes any less organized.
The initial motion is now 300/19. Bertha is approaching the
southwestern edge of the subtropical ridge and should turn
northwestward during the next several hours. A turn toward the
north should occur in about 48 hours as Bertha moves between the
ridge and a deep-layer trough over the southeastern United States.
After that, the cyclone should turn northeastward as it enters the
mid-latitude westerlies. The track guidance remains in good
agreement on this scenario, and the new forecast track is
again generally similar to the previous track.
There are now three possible scenarios for the intensity of Bertha.
The scenario for the official forecast is that Bertha survives its
current lack of structure, land interaction, and dry air
entrainment long enough to reach a more favorable environment in
about 36 hours. At that point, it would likely intensify until
the onset of extratropical transition in 96-120 hours. Using this
scenario, the new intensity forecast is similar to the previous
forecast and calls for Bertha to become a hurricane in about 96
hours. The second scenario is that Bertha degenerates to a tropical
wave as it passes over Hispaniola, with possible regeneration later
when the system reaches the more favorable environment. A new third
possibility involves a low pressure area currently developing over
the northwestern Bahamas. The UKMET and navgem forecast this low to
get strong enough to absorb Bertha in 48 hours or so, while the
other models are less bullish on the its development. Later model
runs should help determine the likelihood of this scenario.
Forecast positions and Max winds
Init 02/2100z 18.4n 68.5w 40 kt 45 mph
12h 03/0600z 20.0n 70.3w 40 kt 45 mph
24h 03/1800z 22.5n 72.7w 40 kt 45 mph
36h 04/0600z 25.1n 74.1w 45 kt 50 mph
48h 04/1800z 28.0n 74.1w 50 kt 60 mph
72h 05/1800z 34.0n 70.5w 60 kt 70 mph
96h 06/1800z 38.5n 63.0w 65 kt 75 mph
120h 07/1800z 43.5n 53.0w 50 kt 60 mph