Grand Junction, Tennessee Weather Forecast Discussion

817
FXUS64 KMEG 202112
AFDMEG
Area Forecast Discussion
National Weather Service Memphis TN
412 PM CDT Sat Sep 20 2025
...New DISCUSSION, AVIATION, FIRE WEATHER...
- Isolated to scattered thunderstorms are possible this weekend, with
  the best chances on Sunday afternoon; severe weather is not
  expected.
- An unsettled pattern will bring increasing rain chances early
  next week as several weak disturbances pass through the Mid-South.
- A more organized storm system is forecast to bring a cooler and
  wetter end to the week, with increasing confidence in
  widespread rainfall Wednesday and Thursday.
&&
.DISCUSSION...
(This evening through next Friday)
Issued at 1226 PM CDT Sat Sep 20 2025
The latest GOES East Water Vapor Imagery shows a weakening MCS
across north central Arkansas with a newly organizing MCS over
extreme NE Oklahoma. Visible satellite shows considerable cirrus
overspreading the area from a weakening MCS in Arkansas. This
cloud cover should suppress most convective development this
afternoon. The exception will be over northeast Mississippi,
where steep low level lapse rates will allow some isolated to
scattered thunderstorms to develop by late afternoon. The
majority of convective activity will taper off around sundown.
HREF guidance suggests that additional showers and thunderstorms
will develop late tonight as the remnants of an MCS move across
northern portions of the Mid-South. Instability will be rather
weak with less than 500 J/kg of MUCAPE and shear will only be up
to around 20 knots. This will limit any strong to severe
thunderstorm development. Another round of convection will
approach near sunrise, but with little instability, any storms
will remain weak and short-lived.
The highest convective coverage across the Mid-South this weekend
will occur Sunday afternoon as upper level heights weaken as peak
heating occurs. Convective coverage will max out around 30% by
late afternoon with ordinary cells as the main storm mode.
The weather pattern will become unsettled early next week as
upper-level flow shifts to zonal. This will allow a couple of
weak shortwaves to translate through the region. The first wave
will arrive Monday with another one on Tuesday. Low instability
and low shear will keep the threat of strong storms low through
this period. A more organized system will move into the region by
the middle of next week featuring a surface low and cold front.
The severe potential still remains unclear as the upper level
pattern is not clearly resolved at this range.
Nonetheless, confidence is increasing for a wetter and cooler
trend as the latest LREF guidance shows better agreement on an
upper low dropping down across the Central Plains and pivoting
into the Lower Mississippi Valley Wednesday into Thursday. Early
rainfall forecast totals could approach 3 inches for areas north
of the I-40 corridor.
&&
.AVIATION...
(18Z TAFS)
Issued at 1226 PM CDT Sat Sep 20 2025
VFR today and tonight.  South to southwest winds generally 8kts or
less today and tomorrow, around 3kts overnight.  An approaching
longwave trough should increase the chance of showers and
thunderstorms tomorrow although timing is questionable. Included
PROB30s for SHRA and TSRA at JBR, MEM and MKL. No precip expected
through the TAF cycle at TUP.
&&
.FIRE WEATHER...
Issued at 1226 PM CDT Sat Sep 20 2025
Fire weather concerns will slowly decrease next week. Rain
chances will tick upwards Monday with widespread rainfall
returning with a cold front by midweek. Conditions will trend
cooler behind the front by late week.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...AC3
AVIATION...JDS

NWS MEG Office Area Forecast Discussion