Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 10/25/20

Area Forecast Discussion

National Weather Service Memphis TN

 932 PM CDT Sat Oct 24 2020

.DISCUSSION...
Another chilly night ahead of us. Cold and cloudy is the main
story for tonight into tomorrow. Lows tonight will generally be in
the lower 50s. Latest radar imagery shows light returns,
indicating some drizzle might still be present in the Mid-South.
No real changes were made to the forecast.

SGW


PREV DISCUSSION... /issued 332 PM CDT Sat Oct 24 2020/

DISCUSSION...

What a difference 24 hours makes? Temperatures are running nearly
35 degrees cooler across the area, in the wake of a cold front.
Heavy cloud cover and drizzle have been commonplace across the
area for much of the day. Aloft, an exiting shortwave can be seen
on GOES Water Vapor Imagery, with nearly zonal flow across the
belt of the Central U.S. Latest KNQA radar sweep reveals light
reflectivity returns, suggesting light precipitation and drizzle
across the area. The latest AMDAR soundings show a pronounced
elevated inversion across the region, which will keep this low
level moisture locked in through at least tomorrow.

Short term...Tonight through Tuesday...

Temperatures are expected to remain nearly steady overnight due to
drizzle and heavy cloud cover. Expect lows in the upper 40s to
lower 50s. Upper level flow will shift more southwesterly
tomorrow, as the upper low off the California coast comes ashore.
With heavy cloud cover nearly locked in place, temperatures will
not warm much. Expect highs to only reach into the low to mid 60s.
Expect dry conditions and slightly warmer temperatures to persist
into Monday.

Split flow over the West Coast will congeal into a large trough
by late Monday as it moves into the Desert Southwest Region.
Downstream of this feature, a cold front will drop down into the
Lower Mississippi Valley and stall over the northwest portion of
our CWA. This will keep low-end chances for rainfall in the
forecast for areas north of I-40 Monday night and Tuesday, with
mostly dry conditions to the south.

Long Term...Wednesday through next weekend.

The long term forecast has now been complicated by the genesis of
Tropical Depression 28 in the Caribbean. This system is now being
resolved in both synoptic models as potentially TS Zeta. Both
models bring the system up through Louisiana Wednesday into
Thursday. This will bring a surge of moisture north into the Mid-
South Wednesday ahead of an approaching surface low coming out of
the Southern Plains. The remnants of the tropical system and the
aforementioned surface low appear to merge as they move through
the region on Thursday. This will likely enhance lift and
convective coverage across the area, and produce generous amounts
of rainfall in its wake. For now, it appears the best chances for
rain will be Wednesday and Thursday, with up to 3 inches of
rainfall possible.

Behind the exiting system, dry northwest flow appears to set up
Friday through next weekend. This would translate to near normal
temperatures and mainly dry conditions.

AC3

AVIATION...
00Z TAFs

Ceilings will remain near the IFR/MVFR threshold tonight, more
likely below this threshold east of the MS River. HRRR model
suggest the -DZ potential may expand to JBR, and increase at the
other TAF sites after 06z with a weak impulse wrapping around the
back side of the departing upper low.

Ceilings will be slow to lift Sunday, as modest surface heating
increases the depth of the mixed layer and the overlying thermal
inversion base. JBR should see flight conditions improve soonest
on Sunday, TUP the latest.

PWB

&&

.AVIATION...


&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$