Scientific Forecaster Discussion
fxus64 kmeg 230854
Area forecast discussion
National Weather Service Memphis Tennessee
354 am CDT Fri Aug 23 2019
a messy, split-flow pattern over the Continental U.S. Will continue to
provide enhanced rain chances and slightly below normal
temperatures across the mid-south through early next week. The
northern stream remains fairly high-amplitude with a ridge
extending north into Manitoba and Ontario and a shortwave trough
diving southeast around the deep wave over eastern Canada. A cold
front extends from just north of Springfield (mo), to Cape
Girardeau (mo), and eastward along the Ohio River.
A cluster of showers and thunderstorms from near Jonesboro to
Union City has developed in the warm sector and is training
slowly east-northeast across the County Warning Area. The cold front will move very slowly
south across the County Warning Area today and tonight, largely masked by
convective outflow, eventually stalling south of tup tomorrow.
Hires cams suggest rain chances will be greatest this morning into
early afternoon as the current complex of storms develops a cold
pool and moves southeast, with more diurnally driven, scattered
storms during the mid/late afternoon period (mainly south of
Limited deep-layer shear may be sufficient to loosely organize
storms, but the severe threat will be relatively low. However,
locally heavy rainfall will be a potential hazard with
precipitable water approaching 2" today. Temperatures will be a
bit below normal today with highs in the mid/upper 80s.
Rain chances continue overnight and the greatest chances will
depend on where the cold front intersects with weak, southerly
winds above the frontal zone. The NAM nest is the most aggressive
of the hires models, but confidence is not really high at this
time. For Saturday, the greatest rain chances will shift south
into north MS closer to the quasi-stationary front.
The stalled front will remain south of the area on Sunday, with an
overrunning pattern continuing to provide ample opportunity for
showers and thunderstorms. The boundary begins to lift back to the
north late Sunday into Monday as a shortwave trough moves across
the middle MS valley, followed by a stronger wave approaching the
Great Lakes early in the week. This will drive and other cold
front into the area by midweek, maintaining the unsettled weather
pattern and slightly below normal temperatures.
The global models indicate a broad ridge developing over the
Southern Plains into the Desert Southwest for the latter half of
next week with a slight northwest flow aloft over our neck of the
Woods. While rain chances won't disappear, they will shift back
closer to climatology (20-30%) to round out of the forecast
Outflow boundaries, an upper level disturbance crossing the
Ozarks, and partially clearing sky will lead to patchy fog/stratus
and increasing convective activity at all the sites this period.
Confidence is low on just how much activity will be thunderstorms.
For now feel jbr will initially have some thunder in vc early and
then the remaining sites later in the period. Lowest visibility down to
LIFR at mkl. Light winds becoming north or northeast at 5-9kts.
Stronger winds may accompany a few afternoon thunderstorms.
Tennessee...dense fog advisory until 7 am CDT this morning for Benton Tennessee-