Area Forecast Discussion
Issued by NWS Corpus Christi, TX
FXUS64 KCRP 291117 AAA
Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
617 AM CDT Wed Mar 29 2017
.DISCUSSION...Update for 12z Aviation.
.AVIATION...Main wx impact this mrng to be from possible
convection. Convection has been struggling to dvlp overnight but
is finally getting its act together more and is likely to impact
KVCT shortly after the start of the TAF period thru mid mrng.
Brief reductions in VSBYs and CIGs possible along with isolated
strong wind gusts. Lower certainty exists as to whether or not
convection will reach/impact KCRP. Potential exists for convection
to dvlp/strengthen vcnty KCRP...but impacts should be brief if
they occur. KALI likely to only experience brief light/moderate
SHRA with KLRD remaining dry. MVFR CIGs possible thru mid mrng
with mainly clear skies thereafter as significantly drier airmass
overspreads the region. Generally weak sfc winds today 5 to 10 kts
.PREVIOUS DISCUSSION... /Issued 444 AM CDT Wed Mar 29 2017/
SHORT TERM (Today through Thursday)...
The leading edge of a surface boundary /and also a gravity wave as
noted from GOES-R satellite imagery/ was analyzed to be located from
KBEA to just west of KALI to NW of KHBV to south of KLRD as of
writing. Behind the boundary, elevated convection has been trying
to develop but is struggling to maintain itself due to limited
moisture depth. Better convective development may occur closer to
sunrise across the Coastal Plains to Victoria where the moisture
depth is prog to be deeper, where instability is prog to be
greater, and where H25 difluence is prog to be a little better.
Any storms that manage to develop this morning will have the
potential to produce small hail /given the extreme elevated
instability values/ and perhaps an isolated strong wind gust.
Precip chances should quickly end by mid morning as a
significantly drier airmass overspreads most of inland S TX as the
aforementioned boundary stalls along the coast.
Temps today are likely to warm into the 90s in the afternoon given
the expected dry airmass and a weak adiabatic downsloping
component. I am a little concerned that I did not go warm enough
for the coastal counties as this synoptic setup can often lead to
incredible warming across the Coastal Plains. However, given the
expected strong inland warming and quasi-cool Gulf SSTs, the
stalled boundary should start to retreat inland in the afternoon
acting as an effective seabreeze. Thus...I have limited Corpus
Christi`s max temp today to only 92 degrees rather than the mid
Near surface moisture values are likely to increase this evening
ahead of the main cold front that is prog to push south across the
region late tonight. The GFS wants to develop light showers
across the Coastal Plains/adjacent Gulf right along/ahead of
FROPA late tonight. Despite impressive dynamical features aloft
/95 to 100 kt H25 jet streak and deep H5 trough/ moisture depth
limited to only the lowest 100mb as well as a thin layer around
H5 should preclude any precip development.
NNW winds should increase late tonight with breezy conditions
possible around sunrise Thurs. Mostly sunny skies with low
relative humidity values and temps near seasonable levels should
make for a nice day on Thursday.
LONG TERM (Thursday Night through Tuesday)...
The deterministic solutions generally agree with regard to the
timing/position of the next upper disturbance...moving SEWD across
the Rockies Friday then slowly approaching TX from the NW
Saturday...moving across TX Sunday/Sunday Night...then lifting NEWD.
Increasing onshore flow expected over the CWA/MSA given the
foregoing upper pattern. At least SCEC conditions expected over the
Coastal MSA Friday Night through early Sunday. GFS deterministic
predict PWAT values to increase to near/above normal values Saturday
over the ERN CWA/MSA. The combination of upper forcing/moisture will
contribute to at least isolated/scattered convection Saturday
Night/Sunday. Strong convection possible given GFS deterministic
CAPE/vertical shear. Drier conditions expected Monday/Tuesday.
MARINE...Strong southeast flow should rapidly weaken this
morning. Seas, however, may be slow to respond and the Small Craft
Advisory has been extended through much of today for the Gulf
waters to account for the hazardous seas. A brief window for
chances of showers or a storm will exist this morning and early
afternoon. A cold front will push south across area waters late
tonight into Thursday morning bringing a brief period of strong
north flow in its wake.
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 92 61 82 58 86 / 40 10 10 0 0
Victoria 88 57 79 55 85 / 50 10 10 0 0
Laredo 92 61 86 60 97 / 0 0 0 0 0
Alice 94 58 84 56 90 / 20 10 0 0 0
Rockport 86 60 79 61 80 / 40 10 10 0 0
Cotulla 91 56 84 56 94 / 0 0 0 0 0
Kingsville 96 59 84 57 90 / 20 10 0 0 0
Navy Corpus 88 63 79 63 81 / 40 10 10 0 0
GM...Small Craft Advisory until noon CDT today For the following
zones: Coastal waters from Baffin Bay to Port Aransas out
20 NM...Coastal waters from Port Aransas to Matagorda Ship
Channel out 20 NM.
Small Craft Advisory until 4 PM CDT this afternoon 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.