Friday, July 12, 2019

No Surprises as Barry Nears Coast...

The 4 PM NHC advisory, as expected, continued the consistent messaging regarding Barry with some subtle changes.  The forward motion has increased slightly from 5 to 6 MPH.   Not a big deal but any increases is good as the faster the motion, the less likely the model predictions of 20-25" of rainfall becomes. The swirl on the visible loop was just one of the vortices rotating around a broad center.  You can pick out another one rotating up from the south.  To me the center appears to be moving very little.  Bruce just showed the color IR that indicates the heavy storms over the Gulf on the south side are NOT coming north yet.   That will probably change later tonight, but the center of Barry is nearing the coast and he is running out of time for development.  It appears the centerline track will be west of Morgan City over Marsh Island & New Iberia before turning northward over Lafayette.  As David pointed out, our heaviest rains may not come until we see the wrap around tail of moisture on Sunday.  However, the NWS rainfall guidance still says 4-8" for metro NOLA.   I'm leaning towards 3-5", but here's the key.  Several rain bands are rotating far away from the center.  One over the Florida beaches with another over the eastern Gulf.  Remember the Forecast "cone of error/uncertainty" is NOT a "cone of impacts".   Impacts can be hundreds of miles east of the centerline and that's what we'll have to watch for tomorrow and Sunday.   I can say the highest water levels for the Mississippi coast are happening now.  IF the westward trend of motion continues, water levels should start to fall after high tides Saturday morning.   Lake Pontchartrain is different.  As the wind direction turns more southerly, the high water in the Lake will be forced to the North Shore flooding Lakeshore Dr.  Noticed the pressure at Boothville is no longer falling while Pt. Fouchon, Patterson & New Iberia continue to fall.  Let's hope this WNW motion continues and the cluster of heavy storms offshore doesn't come north until late tomorrow and Sunday.  That would mean the brunt of the storm goes between Morgan City, Abbeville & Lafayette moving northward just west of Baton Rouge.  FYI...I'll be on 99.5 FM Saturday morning at 9 AM if you want to hear the little fella again.    No need for TV appearance since David and his crew have been doing an awesome job.  Stay tuned!

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