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fxus64 kbro 222021 

Area forecast discussion
National Weather Service Brownsville Texas
321 PM CDT sun Sep 22 2019

Short term (tonight through Monday night): models show a weak
inverted trough moving west under the main northern Gulf Coast 500 mb
ridge. The energy will be best placed to enhance local convection
Monday and Monday night. With ample low level moisture in the
area, the Gulf waters and coastal sections will see isolated to
scattered showers and thunderstorms, with some convection
penetrating a bit farther inland than recent typical sea breezes
on Monday, into the Mid Valley and Hidalgo County. Deeper moisture
coupled with efficient rain processes could result in moderate to
brief heavy rain producers Monday afternoon through evening.
Skies should be mostly clear to partly cloudy tonight with light
southeast winds and a bit of patchy fog across the northern
ranchlands and brush country. Temperatures will trend warmer than
normal by a few degrees through the short term, with partly cloudy
to mostly cloudy skies Monday and into Monday night.

Long term (tuesday through sunday): 500 mb ridging will start off
the longer range period centered over the Gulf of mex with closed
lows bracketing this ridge to the west and east. A major baja
closed low will be located over the western U.S./Mexico border
region while a series of 500 mb closed lows/troughs will stretch
from north to south over the western Atlantic. Meanwhile, a
general weakness on the west side of the 500 mb ridging will be
centered over the deep south Texas/rgv region from tues through thurs.
This will likely help initiate some isold/sct conv. The one
limitation for this feature will be that deep layer moisture will
be pretty limited or will remain concentrated over the western
Gulf. This weakness will get sheared out to the north ahead of the
desert SW closed low which will open up to a trough and will move
into the Texas Panhandle region late thurs/early Fri. As the 500 mb
weakness lifts out to the north and east, the broad ridging will
build westward into next weekend which will maintain overall temps
above climo for the end of sept.

The European model (ecmwf) temps have been consistenty warmer versus the GFS as the
European model (ecmwf) appears to bring in a little drier air over the region until
around thurs. Model blends for high temps appear to lean towards
the warmer European model (ecmwf) numbers throughout the upcoming work week and
this looks reasonable. The European model (ecmwf) and GFS are also in reasonable
agreement for pops through day 7/8 and will maintain the conv chcs
generally in the 20 to 30 % range for the inland and marine
regions through next weekend.

The tropical Atlantic Basin remains active today with NHC
monitoring ts Jerry and Karen in addition to a broad area of low
pressure emerging off of the West Coast of Africa. Ts Jerry is
expected to recurve to the north and NE moving into the northern
Atlantic thur and Fri. Meanwhile, ts Karen is expected to
continue moving in a general northerly direction moving north of
Puerto Rico on thurs and Fri. At this point longer range model
guidance indicates that the 500 mb ridging building over the southeast
U.S. May cause Karen to slow down and possibly stall. Please refer
to the latest outlooks and statements from NHC concerning the
future progress of ts Karen. Http://www.Hurricanes.Gov


Marine now through Monday night: light to moderate southeast
winds and moderate seas will prevail in the short term. A mid
level inverted trough will approach from the east tonight and
Monday, contributing to instability aloft and supplementing moist
low level inflow from the southeast, with isolated to scattered
convection in the forecast for the marine areas. Seas should dial
back slightly tonight through Monday night, though low end small
craft should exercise caution conditions may still develop at
times, especially offshore.

Tuesday through thurs night: broad surface ridging over the Gulf
of mex and the southeast U.S. Will maintain a pretty moderate and steady
southeast low level flow across the Laguna Madre and the Lower Texas Gulf
waters through thurs. Gulf swells will likely remain in the 2 to
4/3 to 5 foot range through thurs. This will keep the Bay and Gulf
conditions under Small Craft Advisory levels, but some periodic scec conditions
cannot be ruled out. Isold/sct conv will remain possible
especially across the Lower Texas Gulf waters due to decent and
persistent maritime cape values.


Preliminary point temps/pops...
Bayview/Port Isabel 78 90 78 90 / 20 30 20 20
Brownsville 79 92 78 93 / 20 30 20 20
Harlingen 77 93 76 94 / 10 30 20 20
McAllen 77 95 78 96 / 10 30 20 20
Rio Grande City 76 98 76 98 / 0 20 10 10
South Padre Island 81 86 81 86 / 20 30 20 20


Bro watches/warnings/advisories...


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