609 
ACUS48 KWNS 160820
SWOD48
SPC AC 160819

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0319 AM CDT Wed Jun 16 2021

Valid 191200Z - 241200Z

...DISCUSSION...
A shortwave trough will continue eastward across the northeastern
states on Saturday/D4 with a surface low over Quebec. Strong
westerly winds aloft will push the surface cold front rapidly east
across New England during the day, with thunderstorms likely.
Predictability issues exist for Saturday/D4, as there are forecast
to be morning storms which may stabilize parts of the area. In
addition, timing differences exist regarding the speed of the cold
front. Probabilities for severe may be added in later updates as
predictability warrants.

For Sunday/D5 through Monday/D6, there appears to be severe
potential over parts of the northern Plains and upper MS Valley, as
a large upper trough amplifies over the Plains and Great Lakes.
There is significant model spread regarding this trough, thus
predictability is too low to introduce severe probabilities.
However, risk areas will be possible in later outlooks as models
come into better alignment. The trough will have an expansive wind
field aloft, and there may be a deepening surface low as well,
supporting an organized severe threat.

..Jewell.. 06/16/2021