Image Department Meteorology
Meteorology_Home Weather_Server News/Seminars
People
Research
Academics Application Contact_Us

Hawaiian_Weather
US_Mainland_Weather
Tropical_Weather
Satellite_Imagery
Radar_Imagery
Marine
Numerical_Models
LAPS
Forecasts
Observations
Archive
Links Disclaimer
Space
SOEST_Home
University_of_Hawaii_Home

 849 
 WTNT41 KNHC 011502
 TCDAT1
 
 TROPICAL STORM ARTHUR DISCUSSION NUMBER   3
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL012014
 1100 AM EDT TUE JUL 01 2014
 
 Radar and satellite imagery indicate that the convective
 organization of the cyclone has improved since the previous
 advisory, and the cyclone is being upgraded based on a sustained
 wind report of 33 kt from Settlement Point (SPGF1) on Grand Bahama
 Island earlier this morning that was outside of the deep convection.
 
 After remaining nearly stationary earlier this morning, Arthur
 appears to to be drifting northwestward now with an uncertain motion
 of 315/02 kt. Otherwise, there is no significant change to the
 previous forecast track. The latest model guidance has continued the
 trend of a pronounced mid-tropospheric trough digging southeastward
 from the upper-midwest into the northeastern and mid-Atlantic region
 of the United States by 72 hours. The 500 mb flow pattern is almost
 identical in the GFS and ECMWF models, which increases the
 confidence in this evolving pattern. As a result, a steady increase
 in southwesterly steering flow over the southeastern United States
 is expected to gradually turn the tropical cyclone northward over
 the next 24-36 hours, and then accelerate the system faster toward
 the northeast on Thursday and Friday. By Days 4 and 5, Arthur is
 forecast to move over the far north Atlantic as an extratropical
 cyclone. The NHC track forecast is just an update of the previous
 advisory track, and lies down the middle of the tightly packed
 guidance envelope close to the consensus model TVCA.
 
 Northwesterly vertical wind shear is forecast by the models to
 gradually subside over the next 48 hours, which should allow the
 cyclone to develop its own upper-level outflow pattern. In fact,
 latest visible and water vapor imagery indicates that cirrus
 outflow has been expanding on the north side of the system during
 the past few hours, suggesting that the shear conditions could
 already be subsiding. The low shear conditions and warm
 sea-surface temperatures should allow for at least steady
 strengthening, and the cyclone is expected to become a hurricane by
 72 hours. The official intensity forecast is similar to the
 latest intensity model consensus IVCN through 36 hours, and then
 slightly higher after that.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  01/1500Z 27.6N  79.3W   35 KT  40 MPH
  12H  02/0000Z 27.8N  79.4W   35 KT  40 MPH
  24H  02/1200Z 28.7N  79.6W   40 KT  45 MPH
  36H  03/0000Z 29.8N  79.5W   50 KT  60 MPH
  48H  03/1200Z 31.2N  78.9W   60 KT  70 MPH
  72H  04/1200Z 35.4N  75.2W   70 KT  80 MPH
  96H  05/1200Z 40.8N  67.3W   65 KT  75 MPH
 120H  06/1200Z 45.5N  59.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
 
 $$
 Forecaster Stewart
 
 
Return to the Tropical Systems Page for ARTHUR

Back to main Tropical Weather page




This page is maintained voluntarily by the MKWC and the UHMET faculty, staff, and students.
It was last modified on: , 17 2014 - 1841 UTC
Send comments to: Ryan Lyman