Forecast Discussion

FXUS64 KMEG 202031

Area Forecast Discussion
National Weather Service Memphis TN
331 PM CDT Fri Apr 20 2018


At 3PM. A cool Spring day is taking place across the Mid-South.
Temperatures are in the mid 60s across the north with lower 70s
across the south under abundantly sunny skies. Evidence of a an
arctic airmass is still present, as dewpoints remain in the 20s
and 30s with relative humidity values below 25 percent areawide.
Temperatures are expected to drop into the low to mid 40s

Short term...Tonight through Sunday...
A large cutoff low, currently over the Four Corners, will
traverse the Southern Plains and push into the Lower Mississippi
Valley during this period. This will bring a prolonged period of
showers and a few thunderstorms to the Mid-South through early
next week.

Ahead of the upper level low, shortwave ridging will persist
across the Mid-South into Saturday afternoon keeping the
atmosphere capped and rain chances nil. At the surface, a warm
front is expected to lift north across the majority of the Mid-
South during the afternoon hours. Temperatures are expected to
top out in the low to mid 70s after the front pushes through.

After sundown, a shortwave trof, embedded in the southwest flow
aloft, will kick off showers and a few thunderstorms. Coverage of
precipitation will increase from west to east as the upper level
low digs southeast. At the surface, a low pressure center is
expected to develop by early Sunday morning over southern
Arkansas and track east southeast across north Mississippi through
Sunday evening. Rainfall totals will likely range from 1 to 2
inches across much of the area, with the heaviest rainfall
expected along and south of I-40. Due to the track of the low, any
severe weather potential will remain confined to our south.

Long term...Monday through late next week...
The pesky upper level low is expected to remain in close proximity
to the eastern half of the forecast area through midweek. This
will keep clouds and at least some low POPs in the forecast
through at least Tuesday night. Temperatures during this period
will remain about 10 to 15 degrees below normal with highs only in
the low to mid 60s. A brief break from the rain is possible on
Tuesday night into early Wednesday as surface high pressure
briefly builds in.

By Wednesday morning, A quick moving shortwave trof and
associated cold front is expected to push through the region
bringing another dousing of rain to the area. Temperatures will
remain slightly below normal through the end of the workweek.




18Z TAFs

VFR to prevail through the period. Light ENE winds will veer to
the SE, Saturday morning, ahead of an approaching upper level low
pressure system. Although some increase in low level moisture will
occur Saturday, the leading edge of marine air will likely only
get as far north as southern MS on Sunday.