Scientific Forecaster Discussion
fxus64 kbro 192315 aaa
Area forecast discussion...updated
National Weather Service Brownsville Texas
615 PM CDT Wed Jun 19 2019
Discussion...updated for latest aviation discussion below.
Aviation...generally VFR conditions expected through the taf
period, with a few brief MVFR cigs working into the coastal
counties this evening and late tonight or early Thursday morning.
South-southeast winds stay moderate overnight and become breezy to windy after
sunrise, with moderate to strong gusts up to 28 kts Thursday
afternoon at hrl and bro.
Previous discussion... /issued 314 PM CDT Wed Jun 19 2019/
Short term (tonight through Thursday night): 500 mb west to east
ridging will continue to lie over the area, along with high
pressure over the Gulf. The main issue in the short term will be
hot weather, with temperatures remaining well above normal.
Overnight low temperatures will be in the upper 70s to lower 80s,
with inland high temperatures on Thursday in the mid 90s near the
coast to triple digits farther west. In conjunction with elevated
dew points, heat index values will poke above 110 degrees for
portions of the County Warning Area on Thursday afternoon, and a heat advisory may
be required. Otherwise, Thursday will see a mix of clouds and sun
and moderate to breezy south southeast winds, with mostly clear
to partly cloudy skies at night and light to moderate winds.
Long term (friday through wednesday): 500 mb ridging will remain
entrenched over the Gulf of mex and the Gulf Coast region into
this weekend. A large trough axis will dig into western states
this weekend. This combination will set the stage for a pretty
strong surface pgf this weekend also which will help maintain
breezy to windy conditions for this weekend. The 500 mb trough
over the western states will then lift out and move eastwards
across the upper Midwest early next week which may weaken the
broad ridge axis over the Gulf of mex region next Mon through Wed
which may provide a brief break in the high heat index values late
in the forecast period.
A narrow band of some deeper tropical moisture values appear to
move over the rgv early next week as the western 500 mb trough
lifts out over the upper Midwest. So will maintain some slgt chc
pops late in the forecast period.
The GFS and European model (ecmwf) models are in pretty good agreement in the
handling of the 500 mb fields through day 7/8. The temps/pops from
both models are in close agreement and run to run consistency with
both models is also pretty stable.
So overall confidence in the longer range forecast wording is
above average at this time.
Marine (now through Thursday night): moderate to fresh southeast
to south winds and moderate seas will prevail as high pressure
over the Gulf interacts with transient plains low pressure
systems. Small craft will need to exercise caution during the
short term due to 15 to 20 knot winds. Seas will build slowly
during the period.
Friday through Monday night: the 500 mb trough axis moving out of
the western states this weekend into next week will likely tighten
up the pgf across the Laguna Madre and the Lower Texas Gulf waters.
This will likely result in an extended period of scec/Small Craft Advisory
conditions along the Lower Texas coastline through next Mon.
Texas...heat advisory until 7 PM CDT this evening for txz248>255-353.