Saturday, August 26, 2017

Hurricane Watch: As Harvey Inches Back Toward The Gulf, Two More Atlantic-side Disturbances

First up, a snippet from Jeff Masters at Category 6:
Heavy Damage in Texas from Harvey; Disastrous Flooding Lies Ahead
.....The forecast: catastrophic, life-threatening flooding expected into next week as Harvey stalls out
An extremely serious situation with few if any close parallels in modern U.S. hurricane history is taking shape over the southeast third of Texas. Computer models remain in strong agreement that the steering currents around Harvey will remain weak through at least Wednesday. As a result, Harvey will spin down while stalled for several days within 100 miles of the central Texas coast (see Figure 5). Even as its top winds decrease, Harvey will continue to pump enormous amounts of moisture into south central and southeast Texas, producing relentless bands of showers and thunderstorms (convection) across a wide swath that will likely include the Houston area. The 12Z Saturday run of our most reliable hurricane tracking model, the European, predicts that Harvey will edge offshore on Monday and Tuesday, which would keep the storm from weakening, and potentially allow some modest re-intensification....MUCH MORE
And from the National Hurricane Center:

Atlantic 2-Day Graphical Tropical Weather Outlook
http://www.nhc.noaa.gov/xgtwo/two_atl_2d0.png
ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Sat Aug 26 2017

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on recently
downgraded Tropical Storm Harvey, located inland over eastern Texas.

1. An elongated area of low pressure stretching across north-central
Florida continues to produce a large area of disorganized
cloudiness and thunderstorms extending from the southwest coast of
Florida northeastward into the western Atlantic.  Although
upper-level winds are not particularly conducive, this system has
the potential to become a tropical or subtropical depression
early next week after it moves off the northeast coast of Florida
on Sunday. The low is forecast to move close to the southeastern
coast of the United States and merge with a cold front by mid-week.
Regardless of tropical cyclone development, the low is expected to
cause increasing winds and rough surf along the coasts of Georgia
and the Carolinas through early next week.  Heavy rain is also
expected to continue over portions of southern and central Florida
during the next day or two. Please refer to products from your local
National Weather Service forecast office for more information on
this system.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...medium...50 percent.

2. A tropical wave over western Africa is forecast to emerge over the
far eastern Atlantic Ocean on Sunday.  Environmental conditions are
forecast to be conducive for slow development by the middle of next
week while the wave moves westward about 20 mph.
* Formation chance through 48 hours...low...0 percent.
* Formation chance through 5 days...low...20 percent.

Forecaster Blake