Dennis, Mississippi Weather Forecast Discussion

204
FXUS64 KMEG 051749
AFDMEG
Area Forecast Discussion
National Weather Service Memphis TN
1249 PM CDT Sun Oct 5 2025
...New DISCUSSION, AVIATION, FIRE WEATHER...
.KEY MESSAGES...
Updated at 1249 PM CDT Sun Oct 5 2025
- Dry conditions and highs in the upper 80s will persist today
  with a cooling trend expected through this week.
- Rain chances return to the forecast starting tomorrow and will
  last into Wednesday. Locally heavy rainfall and a few
  thunderstorms are expected.
- A cold front will pass Wednesday, bringing cooler temperatures
  into next weekend. Highs are expected to be in the upper 70s and
  low 80s.
&&
.DISCUSSION...
(This afternoon through next Saturday)
Issued at 1249 PM CDT Sun Oct 5 2025
Mostly clear weather will continue this afternoon as high
pressure continues to remain over the eastern CONUS. Deep
moisture, which has been in short supply this weekend, is
beginning to advect northward throughout the region ahead of the
arrival of a weak Gulf disturbance later this week. However,
upper-level ridging will keep precipitation out of the area until
tomorrow. Highs will be in the upper 80s, with lows in the 60s
tonight.
Moist advection will continue overnight with upper ridging
slackening as a positively tilted trough slowly moves east across
the Northern Plains. By tomorrow morning, PWATs are to increase
to around 2", which is well above the 90th percentile. Therefore,
scattered diurnal showers and storms are likely tomorrow
afternoon. Even with anomalous PWATs, the lack of any distinct
synoptic forcing or boundaries will keep the threat of flash
flooding localized areas that see any training.
Through Monday night and early Tuesday morning, the upper trough
over the Northern Plains will have amplified and traveled to the
Great Lakes. Scattered showers are likely to still be ongoing at
this time as southerly moist advection continues with marginal
(500-1000 J/kg) MUCAPE. By 12z, NAM/RAP/HREF guidance all have a
distinct zone of N/S oriented 925-850 mb frontogenesis occurring
along and east of the Mississippi river, gradually propagating
eastward throughout West Tennessee during the day. There are
discrepancies with regards to the position and evolution of this
boundary within this suite of models, but confidence is good that
a zone of increased rainfall will accompany the boundary as it
moves east. This discrepancy has kept NBM QPF through Wednesday
below 1.5", which should increase as we move further into the CAM
window. Regardless, the potential for a slow-moving zone of
training storms has markedly increased since yesterday where
elevated flash flooding concerns are possible Tuesday. Rain will
continue into Tuesday night and Wednesday morning as a more
concerted frontal passage occurs. Rain is expected to end by 00z
Thursday after the front has made it south of the region. When all
is said and done Wednesday, most areas will receive at least 1"
of rain, with upwards of 2"+ possible where training storms are
able to persist.
Cooler temperatures will take over for the rest of the forecast
into next weekend as northwest flow and surface high pressure
locks in temperatures behind the cold front. Highs are anticipated
to be in the upper 70s and low 80s. The front will stall near the
Gulf Coast, making it difficult for moisture to travel inland and
keeping our PoPs low after Thursday through the end of the period.
&&
.AVIATION...
(18Z TAFS)
Issued at 1249 PM CDT Sun Oct 5 2025
VFR conditions continue for the rest of the day. As a disturbance
moves up from the Gulf Coast overnight, scattered showers will
start to pick up from south to north as the system enters the
airspace. This looks like bonafide widespread light showers,
warranting prevailing precip for all sites tomorrow
morning/afternoon. In addition to showers, low clouds will also
accompany this disturbance. MOS guidance and a few deterministic
CAMs wanted to be extremely pessimistic with ceilings late in the
period tomorrow mid-morning (as low as LIFR), but overall HREF
mean ceilings and model discrepancy did not lend enough confidence
to go lower than MVFR in the TAFs. This will be a focus point for
changes with subsequent forecasts. Winds generally look to remain
east/southeasterly 5-10 kts through the period.
CAD
&&
.FIRE WEATHER...
Issued at 1249 PM CDT Sun Oct 5 2025
Fire weather concerns remain low with minimum relative humidity
values sticking around 40 to 50 percent. 20 ft winds are slightly
elevated today with gusts to around 20 mph possible. Wetting rains
will keep fire concerns low through the middle of the week with
anywhere from 1 to 2 inches of rainfall expected across much of
the region with the potential for locally higher rainfall totals.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...JAB
AVIATION...CAD

NWS MEG Office Area Forecast Discussion