08 August 2002

Bertha reforms, Cristobal getting absorbed into trough.

Not long after my update was sent out yesterday mentioning how healthy
the remnants of Bertha looked once she re-entered the Gulf, she was
upgraded to a Tropical Depression (at 21Z).  From what I gather, the
upgrade was based largely on the immediate and impressive effect the
water had on her convection and structure.  Since then, she has changed
little and is still moving slowly toward the southern Texas coast.

At 15Z today, TD Bertha was located at 27.6N 95.7W and tracking WSW at
7kts.  Intensity has held fairly steady at 25kts and 1010mb, but some
further strethening is not out of the question, in my opinion. 
Currently 110 miles east of Corpus Cristi and heading that way, I
wouldn't be surprised if a Tropical Storm Watch was issued for the
southern Texas coast (if the recent healthy trend in centralized deep
convection keeps up).  Over the last 6 hours or so, we've seen a drastic
return of a cold CDO, indicating that she may be on the verge of
intensifying already.  Since the speed and direction are not expected to
change much, we can anticipate a landfall at about 1am on Friday morning
on the northern side of Padre Island (just miles north of where Bret '99
hit as a CAT4 on 8/22 at 23Z), south of Corpus Christi.

TS Cristobal hasn't changed too much since the last advisory, and has
been behaving as forecasted.  The steering flow has been weak, and his
track reveals that... not much more than an eastward meander.  However,
as his circulation becomes more intertwined with the advancing trough,
the motion will pick up and become more northeasterly.  In fact, the
merging is already well underway; what remains of Cristobal is an area
of deep convection and an elongated circulation at the trailing end of a
cold front (with the primary Low over Nova Scotia).  

At any rate, NHC is still writing advisories on the storm.  The 15Z
position is 30.0N 73.8W and moving ENE at 5kts.  Winds are 40kts with
MSLP of 1000mb.  No strengthening is forecast, although it's possible
that once he's transitioned to an extratropical cyclone, the Low could
be baroclinically enhanced and winds could get stronger.  He will not
threaten land.

Lastly, there's a broad area of disturbed weather that moved off Africa
yesterday and is now at about 8N 19W.  It's got a diffuse region of
vorticity to work with, has good upper-level divergence, and but is
embedded in about 20kts of easterly vertical shear.  It is (temporarily)
moving into lower shear, so is worth watching.

Please visit my tropical Atlantic headquarters.

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