Area Forecast Discussion
Issued by NWS Memphis, TN

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FXUS64 KMEG 190839

Area Forecast Discussion
National Weather Service Memphis TN
339 AM CDT Sat Aug 19 2017

A well-defined shortwave trough is moving east into the Ohio
Valley early this morning, providing large scale forcing for
ascent across the Mid-South. A strong jet streak extends
northeast just downstream of this trough, with enhanced vertical
motion in the right entrance region. A few storms were able to
develop this evening and continue to move across the southwest
quadrant of the CWA at this time, but this activity will continue
to decay over the next few hours. A few additional showers and
thunderstorms will be possible today, primarily over north MS.
Generally dry conditions are anticipated across the remainder of
the Mid-South today (although a stray storm can`t be ruled out).
Temperatures will warm into the lower 90s across most of the CWA
with afternoon heat indices between 100-105F in many areas. A few
areas will be close to the 105F threshold, but at this time we do
not think a Heat Advisory will be necessary.

Similar conditions are anticipated across the Mid-South on
Tuesday. A building ridge will result in mid-level height rises in
the wake of the departing shortwave trough. This should help push
temps up a degree or two tomorrow and limit the areal extent of
diurnal convection. PoPs are only 20-30% for Sunday with most
areas likely remaining dry. Again, heat indices will range from
100-105F, but aren`t expected to get any higher.

Monday`s forecast continues to be focused on cloud cover and rain
chances around the midday period. At this time, rain chances will
likely hold off until afternoon with a diurnal Cu field developing
by midday. This should provide decent eclipse viewing conditions
for most areas, but some areas may be obscured by some puffy
cumulus clouds. Rain chances for Monday afternoon are confined to
the western half of the CWA. Temperatures will again be in the
lower 90s, but that potential 10-15 degree drop between 1-2 PM
could make the forecast tricky given my limited eclipse
temperature forecasting experience.

The ridge breaks down over the southeast CONUS on Tuesday as a
strong trough moves east across the Great Lakes. The trough axis
is progged to extend SSW of the parent trough and will provide
some decent ascent across the area Tuesday night into Wednesday.
Rain chances ramp up to 30-40% on Tuesday, but will continue the
upward trend through Wednesday when a cold front moves through the
Mid-South. As of now, rain chances are in the 50-60% range but
should taper off quickly by Wednesday night.

Pleasant weather is anticipated Thursday and Friday in the wake of
this cold front. Drier, cooler air will settle over the region
with afternoon highs in the mid/upper 80s. Given the forecast dry
air and clear skies, some areas may cool to near 60 degrees
by sunrise Friday and Saturday. Generally dry conditions are
expected across the Mid-South next weekend as the current forecast
maintains a westerly track for Tropical Storm Harvey, moving this
system across the Yucatan toward Tampico, Mexico.



/06z TAFs/

VFR conditions will persist through the forecast period outside of
some vsby reductions in fog late tonight into early Saturday
morning. A few showers will be possible around KTUP as a complex
of storms weakens and moves across northeast Mississippi. A weak
cold front will stall across the region on Saturday with
additional isolated to scattered showers and thunderstorms. Winds
should remain rather weak, below 6 kts, through the forecast





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