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Area forecast discussion 
National Weather Service Brownsville Texas
314 am CDT Wednesday Sep 2 2015

Short term /today through Thursday/...water vapor imagery shows a
circulation over East Texas...with drier air...evident over central
Texas...following the cyclonic flow south...while unsettled weather
continues over the northwest Gulf. The GFS shows a drier layer
moving over deep south Texas from the west today. Thus...kept probability of precipitation
between isolated and scattered for today for the eastern two thirds
of the County Warning forecast precipitable water of 1.8 inches will support a sea
breeze hinted at by the hrrr...but it may be weak and not able to
penetrate much deeper than the coastal counties...perhaps into the
Middle Valley. The upper low height center appears to shift slightly
farther south on Thursday...but centered off the Lower Texas coast...
better placed to instigate marine convection than heavy rain over
the coast and inland. The NAM guidance is odd member out showing
higher end chance probability of precipitation late Thursday. At a minimum...may see a more
efficient sea breeze. Other weather parameters will not be much
different than they have been.

Long term /Thursday night through Tuesday/...models forecast a
midlevel inverted trough to be located across our coastal
waters Thursday night and slowly progress westward and weaken
Friday. Middle level high pressure will build in as the trough
dissipates for the weekend into early next week. Will continue
isolated to widely scattered showers and storms Friday for much
of the County Warning Area Friday then mostly curtailing probability of precipitation to the coastal
counties and coastal waters where best moisture and instability
will be located. Further west under more of the influence of the
middle level high... decreased probability of precipitation and clouds and raised high
temperatures a few degrees reaching the century mark once again
across the brush country. Surface high pressure will be located in
the western Gulf much of the extended and with a shortwave trough
dropping in the Pacific northwest then moving northeastward across
the northern tier states...surface winds will experience an uptick
each afternoon with gusts up to 25 miles per hour in spots.


Marine /today through Thursday/...the surface pressure gradient
will remain relatively weak through the short term...dominated by
synoptic scale high pressure over the northeast Gulf...resulting
in light to MDT southeast winds and low seas. Meanwhile...500 mb
weakness aloft and low level moisture sourcing from the Gulf will
keep unsettled weather alive...with scattered showers and
thunderstorms mentioned in the forecast.

Thursday night through Sunday...light to moderate southeast and
low to moderate seas will prevail across the Lower Texas coastal
waters during this period. No scec or Small Craft Advisory anticipated. Isolated to
scattered showers and storms will be possible through the weekend.


Preliminary point temps/pops...
Bayview/Port Isabel 88 77 90 79 / 30 30 30 30
Brownsville 89 76 90 78 / 30 30 40 20
Harlingen 91 76 92 76 / 30 20 30 20
McAllen 93 77 94 78 / 30 20 30 10
Rio Grande City 94 75 96 77 / 30 20 20 10
South Padre Island 84 79 85 80 / 30 30 30 40


Bro watches/warnings/advisories...


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Short term...54
long term...55

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