Arlene hasn't gone anywhere and has accumulated more water vapor.

April 22, 2017

1230.18z 

UNISYS Water Vapor Satellite of North and West Hemisphere (click here for 12 hour loop - thank you)

There is a frigid air mass across most of the USA and even into Mexico.The eastern coastal areas are warm below Pennsylvania or the 41st latitude.

The milibars have been consistently dropping for the past three days. As much as I would like this storm to dissipate, I don't believe it will, especially considering the Gulf Stream, too.

It also move four degrees west in six hours. There is an airmass entering from the west coast providing enormous pressure to move other systems to the east, however, it is during that same push, Arlene move west and north. Definitively.

Date: 19-21 APR 2017

Tropical Storm ARLENE
ADV  LAT    LON      TIME     WIND  PR  STAT
  1  31.90  -40.90 04/19/12Z   30   995 SUBTROPICAL DEPRESSION
  2  32.40  -40.00 04/19/18Z   30   996 SUBTROPICAL DEPRESSION
  3  33.20  -39.30 04/20/00Z   30   996 SUBTROPICAL DEPRESSION
  4  34.40  -39.30 04/20/06Z   30   996 SUBTROPICAL DEPRESSION
  5  36.10  -40.00 04/20/12Z   30   996 TROPICAL DEPRESSION
  6  37.70  -42.00 04/20/18Z   40   993 TROPICAL STORM
  7  39.40  -44.20 04/21/00Z   45   993 TROPICAL STORM
  8  40.00  -48.00 04/21/06Z   45   993 TROPICAL STORM

April 22, 2017

1330.18z

UNISYS Water Vapor GOES East Satellite (click here for 12 hour loop - thank you)

Given the growing strength of the tropical storm, it will incorporate the air mass currently moving offshore North America and realize some open ocean to proceed further toward the USA at higher than 'normal' altitudes. It is possible outcome and I can't ignore it.

It is a push me-pull you system. The west coast storm is pushing and the east coast tropical storm is pulling. When the water vapor currently over Kentucky and Tennessee reach the tropical storm, it will accelerate, drop it's central pressure and become a stronger storm.

It is the way I see it.