Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Corpus Christi Texas
1057 PM CST Thursday Nov 26 2015
Discussion...update for 06z aviation cycle.
No changes from the 00z tafs. Added an extra line for Friday
Overnight...MVFR to IFR. Scattered showers across the region so
have vcsh in some terminals. Expecting MVFR deck to develop or
move into the region from the south. Should lower to IFR at
kvct/kali after midnight, possibly even going down to LIFR for
period through sunrise. Light southeasterly winds. Continue the
amend not schedule overnight for klrd. Medium confidence.
Friday...rebounding back to VFR by later in the afternoon. Not
expecting much change to what we experienced on Thursday, though
no two days are exactly alike. There will be a lot more moisture
across the region and scattered showers possible but with stronger
winds aloft expecting the ceilings to scatter out again with gusty
southeasterly winds. Medium confidence.
Friday night...back down to MVFR/IFR. We will lose the gusts by
late evening allowing the low-level moisture to pool again across
the region around the low-end MVFR/IFR level. Medium confidence.
Previous discussion... /issued 1005 PM CST Thursday Nov 26 2015/
Discussion...not too many changes to the grids this evening.
Adjusted probability of precipitation a tad to allow for a drier forecast late this
evening before another increase in isentropic lift commences after
midnight...mostly across the eastern zones. Added some patchy fog
to the grids for the overnight hours. Also removed the mention of
thunder for the overnight period.
Previous discussion... /issued 305 PM CST Thursday Nov 26 2015/
Short term (tonight through Friday night)... isolate/scattered -shra's are
expected through tonight as isentropic upglide continues across S
Texas. The upglide combined with embedded upper level short waves and
pwat's nearing 2 inches will increase rain chances through Friday. The
highest probability of precipitation will be across the northern County Warning Area due to closer proximity to
upper jet. Best chance of convection will be Friday night as a weakening
cold front approaches S Texas. Models differ on timing but went with
the consensus of the boundary drifting into the northwest County Warning Area between 06-12z
Friday and meandering across the area. Also showed cooler Minnesota temperatures and
lower dewpoints across the northwest County Warning Area Friday night. As for winds...am
expecting a breezy day on Friday in response to the low pressure along
The Rockies and a low level jet of around 30kt. A moderate onshore flow will
persist across the coastal waters as well. A long fetched east-southeast flow
across the Gulf has resulted in seas increasing to 7-8ft and long
period swells of 9 second. This will continue to produce tidal overflow
around 2ft above mean sea level during the time of high tide and a high risk of
rip currents through tonight. The rip current risk and coastal Flood
Advisory may need to be extended on Friday but there is some
uncertainty as some models show a more southerly wind direction developing and
seas/periods decreasing on Friday. Therefore...will let later shift
look at latest model solutions to determine if the advisory needs to be
extended into Friday.
Long term (saturday through thursday)...the deep upper low over the
Great Basin Saturday will lift northeast through the central rockies
Sunday and then move into the Central Plains Monday. Forecast dilemma
will be how far does the front move solely based on density before
it stalls out. NAM still faster than the GFS/European model (ecmwf) with cold front.
Will lean toward the GFS/European model (ecmwf) and bring the front into the northern
and western counties Saturday and stall over the coastal
plains...with front finally pushing offshore Sunday night. Models
keep very high moisture over the region for Saturday with the
frontal boundary slowly moving through the area. Kept likely probability of precipitation
for the northern counties and 50 percent going for southern
counties. Good rain chances will continue into Sunday and diminish
some for Monday. European model (ecmwf)/GFS show a weak short wave trough moving out
of northern Mexico into south Texas Tuesday/Wednesday. Will show a
gradually increasing chance for showers Tuesday and Wednesday. As
the upper low moves through the Great Lakes region...surface high
pressure will build south through the plains and reinforce cool air
mass over the region through the week. Did mention a chance of
thunderstorms Wednesday as there may be enough influence from the
right entrance region of an upper jet to increase lift over south
Preliminary point temps/pops...
Corpus Christi 73 79 71 74 59 / 30 30 30 50 40
Victoria 70 79 61 64 51 / 30 50 60 60 50
Laredo 73 83 62 63 51 / 20 30 40 50 40
Alice 72 80 71 74 55 / 20 40 30 50 40
Rockport 73 78 70 73 61 / 30 30 40 50 40
Cotulla 71 81 58 60 50 / 20 50 70 60 50
Kingsville 74 81 71 75 58 / 20 30 20 50 40
Navy corpus 73 77 72 74 63 / 30 30 20 50 40
Texas...high rip current risk until 6 am CST Friday for the following
Coastal Flood Advisory until 4 am CST Friday for the following
zones: Aransas...Calhoun...Kleberg...Nueces...San Patricio.
GM...Small Craft Advisory until 6 am CST Friday 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.