Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 09/18/20
Area Forecast Discussion
National Weather Service Corpus Christi TX
831 PM CDT Thu Sep 17 2020
.DISCUSSION...
Showers and thunderstorms have diminished across S TX this
evening. However, a few storms across EWX`s area is currently
approaching the northern portions of the CWA. Short range models
prog isolated weak convection through midnight, then convection
is progged to increase overnight, mainly across the coastal
waters. Have tweaked pops to account for this expected trend
tonight. With all of the convection today and this evening, temps
and winds have been all over the place, therefore have also adjusted
the grids to account for this.
&&
.PREV DISCUSSION... /Issued 639 PM CDT Thu Sep 17 2020/
DISCUSSION...
Update for 00Z Aviation.
AVIATION...
Convective activity this afternoon is beginning to wane this
evening. A few thunderstorms are attempting to develop across the
Coastal Plains but are expected to diminish with the loss of
daytime heating. For now, have a mention to thunder across all TAF
sites until 03-04Z. Overnight, light northerly winds will persist
with VFR conditions prevailing. Showers and storms will develop
over the waters during the morning hours and move inland during
the day. However, coverage is expected to be less than today. A
moderate northeasterly flow is expected across the eastern 3
terminals tomorrow afternoon.
PREV DISCUSSION... /Issued 404 PM CDT Thu Sep 17 2020/
SHORT TERM (Tonight through Friday Night)...
Scattered to numerous showers and thunderstorms over the region
will linger into the evening hours but expect coverage will
decrease slightly to scattered for this evening and then become
isolated overnight. Convection limited over the Gulf waters at
this time but expect activity will steadily increase in coverage
especially during the overnight hours as the mid to upper level
trough axis moves into south Texas.
The mid to upper level trough will be moving into the northwest
Gulf of Mexico on Friday. Moisture levels will diminish a little
more over inland areas on Friday. But there will be sufficient
instability by the afternoon to see scattered convection develop
in the afternoon over most of south Texas with better chances over
the southern Coastal Bend.
Activity will diminish by early Friday evening as drier air
finally moves into south Texas with the mid to upper level trough
drifting a little farther east into the Gulf. Dry and mild
conditions will occur overnight for the area with decreasing
clouds.
Tide levels will remain elevated into Friday as tides are running
from 1.6 to 2 feet above expected. Even though tides will fall be
advisory criteria this evening, will rise back to above 2 feet MSL
during the night and continue through the day Friday. Will likely
be extended into Friday or possibly upgraded. Bay levels in Corpus
Christi Bay near 2 feet as well. Will continue Coastal Flood
Advisory as configured through 00Z Saturday.
LONG TERM (Saturday through Thursday)...
The mid/upper level trough that has kept scattered convection over
the area will weaken and lift out of the area. High pressure will
build in, bringing more subsident and drier air. PWATs will drop to
below 1.0 inches for most of the area, though the immediate coast
and coastal waters will keep PWAT values near 1.25-1.5 inches. As
daytime heating provides some instability, we should expect some
isolated showers and thunderstorms Saturday and Sunday near the
coast and over the waters.
The big story for the long term is the tropics. An area of low
pressure over the southwestern Gulf of Mexico continues to become
better organized. NHC has given this a 90% chance of development
over the next 48 hours, so we do expect this will be a tropical
cyclone during the long term period. A hurricane hunter aircraft
will be flying into the system to get more information on this
system. Model agreement on this system is terrible. Most models do
have the system becoming a tropical cyclone; however, the track of
this system is unclear. The ECMWF brings the system near the Middle
Texas Coast, the CMC has it hitting the Middle Texas Coast, the GFS
has it bouncing along the coast up into the northern Gulf...there
are several other possible solutions. The long and short of it, is
that the development of the high pressure ridge and the forward
progress of a weak boundary that will stall over the waters will
ultimately determine the track and, indirectly, the strength of the
system.
MARINE...
A weak to moderate offshore flow tonight will become moderate/SCEC
on Friday. The moderate flow will approach moderate to strong/SCA
Friday night over the offshore waters. Scattered showers and
thunderstorms early this evening will increase to numerous late
tonight into Friday. Shower and thunderstorms will diminish to
isolated to scattered Friday night.
Northeast flow Saturday will increase to moderate. Small Craft
Should Exercise caution are likely to begin Friday night, but Small
Craft Advisory could be possible through the middle of the week.
Isolated to scattered showers and thunderstorms over the weekend
with increase to scattered to numerous beginning early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 73 88 70 87 68 / 30 50 10 10 10
Victoria 73 90 67 86 65 / 30 40 0 10 10
Laredo 70 89 68 87 65 / 20 50 20 10 0
Alice 72 89 68 87 66 / 30 50 10 10 10
Rockport 77 88 73 89 72 / 30 40 10 10 20
Cotulla 70 90 68 88 63 / 30 40 10 0 0
Kingsville 72 89 69 87 66 / 30 60 10 10 10
Navy Corpus 77 87 75 88 73 / 40 50 20 20 20
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...Coastal Flood Advisory until 7 PM CDT Friday For the following
zones: Aransas Islands...Calhoun Islands...Coastal
Kleberg...Coastal Nueces...Coastal San Patricio...Kleberg
Islands...Nueces Islands.
GM...None.
&&
$$
TE/81...SHORT TERM
Area Forecast Discussion
National Weather Service Memphis TN
824 PM CDT Thu Sep 17 2020
.UPDATE...
No major changes to forecast. Made minor adjustments to update
short term.
&&
.PREV DISCUSSION... /issued 630 PM CDT Thu Sep 17 2020/
DISCUSSION...
A nearly flawless weather pattern is expected over the Mid-South
for the next 7 days. Highs in the 70s, lows in the 50s, along
with low humidity and rain-free weather will be the rule. The only
fly in the ointment will be the evolution of INVEST 90L over the
southwestern Gulf. It`s too early to tell where the system will
track, as models are just beginning to latch onto it. However,
synoptic models will start to ingest data soon, as aircraft are
flying through the system as we speak.
Currently, a front remains stalled along the I-40 corridor. North
of the front, dry air has already worked its way into portions of
the Mid-South evidenced by the 50s dewpoints. Latest GOES visible
satellite imagery shows the remnants of Sally tracking along the
Georgia and South Carolina border. As Sally tracks northeast
overnight, upper level flow is expected to shift more northwesterly
and help push a reinforcing front through the entire Mid-South by
tomorrow morning. With little moisture to work with, only clouds
are expected to accompany this boundary.
Surface high pressure will build into the Mid-South through early
next week. This will keep a favorable airmass over the region.
Expect sunny skies, low humidity, and temperatures about 5-10
degrees below normal. Highs will be in the 70s each afternoon with
lows in the 50s each morning. The subtropical ridge will build
back into the central U.S. by the middle of next week. Went ahead
and kept the forecast dry for now, but a tropical disturbance
could easily change the long-term forecast. The Gulf of Mexico
looks to stay very active through at least the end of September.
AC3
AVIATION...
00Z TAF
VFR conditions for TUP and JBR through the TAF cycle. MVFR
conditions expected at MEM and MKL due to some low stratus with
ceiling heights ~1500ft around the 12-15Z timeframe. Conditions should
improve after that to VFR for those two locations. Winds are
currently in the 7-10kt range and are generally northerly. Winds
will pick up 9-14kts with gusts 20-25kts and be more NNE.
SMW
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$