149 
FXUS64 KCRP 111246 AAA
AFDCRP

Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
646 AM CST Fri Dec 11 2020

.DISCUSSION...

Update to increase wind over the Coastal Bend and adjacent bay
waters. 30-40 knot winds aloft, yet anticipate that vertical 
mixing will be limited. Nevertheless, expect 15-20 knot wind over
portions of the Coastal Bend and over the bay waters. Updated the
ALI/CRP/VCT TAFs to include non-convective vertical wind shear
until 14z today.

&&

.PREV DISCUSSION... /Issued 549 AM CST Fri Dec 11 2020/ 

DISCUSSION...

Note Aviation Discussion below corresponding to the 12z TAFs.

AVIATION...

VFR conditions expected during the TAF period over the West. MVFR
conditions anticipated over the Central/East this morning, then
transition to VFR from west to east this afternoon/evening in
response to a frontal boundary. Isolated showers and 
thunderstorms are expected near the boundary over the Victoria 
Crossroads/northern Coastal Bend, and to a lesser extent over the
southern Coastal Bend. Predominate VFR expected areawide after 00z
Saturday. Generally weak to moderate south wind in advance of the
front, followed by northwest wind after frontal passage. Generally
light west wind expected overnight.

PREV DISCUSSION... /Issued 407 AM CST Fri Dec 11 2020/ 

SHORT TERM (Today through Saturday)...

An upper level disturbance is predicted to move across the SRN 
Plains/TX today (significant dynamics over the CWA with 700-300mb
Q-vector convergence and under the RRQ of an upper jet streak per
the GFS/NAM deterministic runs) then lifts NEWD, while another
system enters the Rockies tonight/Saturday. The NAM/GFS predicts 
PWAT values above normal this morning over the CWA. In response to
the first upper system, a surface boundary/front is expected to
move EWD across the CWA today, then slowly move offshore
tonight/Saturday. Isolated/scattered convection expected over the
ERN CWA today, with instability as the limiting factor. Only the 
NERN CWA is expected to have sufficient surface and elevated CAPE 
to generate thunderstorms. Only isolated elevated convection 
anticipated over the SERN CWA, yet mainly showers. No convection
expected over the WRN CWA given near zero surface and elevated 
CAPE expected per the NAM deterministic (although the lift of a 
convectively unstable layer may result in isolated convection over
the west, not confident to add precipitation to the west.) Much 
drier conditions are expected from west to east this afternoon/ 
tonight in response to the surface trough. A weak surface high 
pressure system expected over the CWA Saturday.

LONG TERM (Saturday Night through Thursday)...

An upper low will approach the TX Panhandle Sat night which will 
deepen surface pressure across W TX into northern Mexico. The 
surface high will shift east with a warm front lifting north across 
S TX. This will bring increasing moisture across the area through 
early Sunday morning. The WAA will lead to above normal highs for 
Sunday. The upper low will push a cold front into S TX Sunday and 
off the coast by late Sunday afternoon or evening. The NAM is a tad 
faster with the frontal passage, but overall general agreement with 
models progging some precip across northern and eastern portions of 
the CWA beginning early Sunday morning and increasing through Sunday 
afternoon as the front moves southeast across S TX. Best chance for 
convection will be across the Victoria Crossroads and over the gulf 
waters due to deeper moisture and moderate instability. Models prog 
quick drying from west to east through Sunday night along with 
breezy north winds and cooler temps Sunday night and Monday. 

A progressive upper pattern will bring another upper trough toward 
TX, which will push the surface high east of the area with winds 
shifting quickly back to the southeast by Monday afternoon/evening. 
The second upper trough will push another cold front through S TX by 
Tue afternoon or evening. This will maintain mild highs and chilly 
lows through middle of next week. 

Model solutions diverge quite a bit the latter part of next week. 
Went with the NBM for Thu which brings onshore flow back to S TX 
along with slightly warmer temps and increasing low level moisture. 

MARINE...

Isolated/scattered convection expected today in response to an
upper level disturbance/moisture/approaching boundary. Much drier
conditions expected tonight/Saturday. A weak to moderate onshore 
flow is expected Saturday night through much of the day Sunday 
ahead of a cold front. The cold front is forecast to move off the 
coast by late Sunday afternoon or evening with strengthening 
northerly flow developing in its wake through Sunday night. Strong
to very strong winds with possible gusts approaching gale, are 
expected Sunday night. Advisory conditions are likely Sunday 
night. Winds relax through the day Monday, becoming onshore by 
Monday evening as high pressure moves east of the area. Another 
cold front can be expected late Tuesday afternoon or Tuesday night
with strong north winds developing once again in its wake. 
Isolated to scattered showers and a few thunderstorms will be 
possible Saturday night through Sunday ahead and along the cold 
front, then decreasing from west to east Sunday night behind the 
cold front.

&&

.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi    81  54  77  59  80  /  10   0   0  10  10 
Victoria          77  51  72  52  75  /  40   0   0  20  40 
Laredo            81  53  80  59  79  /  10   0   0   0   0 
Alice             83  53  81  57  81  /  10   0   0  10  10 
Rockport          77  56  74  60  78  /  30   0   0  20  30 
Cotulla           80  48  79  53  76  /  10   0   0   0   0 
Kingsville        82  53  79  57  82  /  10   0   0  10  10 
Navy Corpus       76  59  73  64  77  /  20   0   0  10  20 

&&

.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until 6 PM CST this evening For the 
     following zones: Waters from Baffin Bay to Port Aransas 
     from 20 to 60 NM...Waters from Port Aransas to Matagorda 
     Ship Channel from 20 to 60 NM.

&&

$$

WC/87...SHORT TERM