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Area forecast discussion 
National Weather Service Brownsville Texas
302 PM CDT Friday Mar 27 2015

Short term.../now through Saturday night/...latest water vapor imagery shows
a broad upper ridge dominating the western portion of the state while trough
moves east across the eastern Continental U.S.. the rest of today into tonight...surface
ridge will shift east centered over the Lower Texas Gulf waters. This allows
the winds to veer southeast tonight. The temperatures will be cool once again
overnight ranging from the middle 50s along the Rio Grande to low to middle 40s over
the ranchlands.

Saturday...Ridge continues its progression eastward while surface low pressure
strengthens across West Texas. This will result in southeast winds increasing
in the afternoon with good daytime heating as the dry air remains in over the
area and high pressure is still in control. The southeast winds will increase
between 15 to 25 miles per hour in the afternoon hours. Abundant sunshine will allow for
temperatures to warm up into the 80s along the coast to the middle and upper 80s
towards the western counties. Saturday night...the southeast winds will diminish and
remain light overnight. With greater dewpoints filter in from the southern
Gulf...the temperatures begin to climb up into the 60s near the coast and 50s
in the northern ranchlands.

Long term /Sunday through Friday/...the long range pattern
generally consist of a weak zonal through the period with a
subtropical disturbance moving through Tuesday into Tuesday night
giving the County Warning Area the only significant chance of rain in the next 7
days.

Ridging Sunday and Monday shifts east with moist southerly flow
is well underway. Outright breezy to windy conditions develop
Sunday and may be maintained Monday as the next upstream shortwave
approaches West Texas. GFS is showing a faster west to east flow
with the disturbance through the period and remains the most
consistent of the two deterministic models as well as the
ensemble models. As for convection chances Tuesday have kept the
current time of Tuesday afternoon for the highest chances although
the European model (ecmwf) keep higher chances through Tuesday night with its
slower handling of the upper disturbance. Parameters for
thunderstorms are decent for garden variety type thunderstorms
and nothing like the isolated severe storm that hammered mission
and McAllen Thursday. Middle level lapse rates in the 7.5c/kg cape
values between 1000-1500 j/kg and decent diffluence producing
moderate large scale ascent should be sufficient to provide the
area with a few strong storms.

Zonal flow resumes Wednesday through the end of next week as the
subtropical ridge builds over central Mexico and nudges into deep
south Texas. At the surface the Spring Time warm southerly is
maintained with little variation in temperatures expected for the
entire period with exception on Tuesday with the higher rain
chances. Temperature guidance in good agreement and a general
blend with slightly nudge with the GFS looks on track.




&&

Marine...now through Saturday night...light winds prevail today across the
Gulf waters with high pressure in control. Tonight...high pressure shifts
towards the Gulf veering winds southeast. The southeast winds will remain moderate
Saturday night into Sunday as the gradient strengthens with the potential for
scec and marginal.

Sunday through Wednesday...moderate to strong southerly flow
becomes established Sunday and Monday as high pressure over the
Gulf interacts with the approach of the next upstream upper
trough. Small craft advisories over the Laguna are looking
reasonable each afternoon with exercise caution values offshore.
The upper trough moves into the western Gulf Tuesday night with no
change of wind direction as the into moves east of the area
Wednesday. Showers and thunderstorms to accompany the disturbance
with best chances Tuesday afternoon and night.

&&

Preliminary point temps/pops...
Bayview/Port Isabel 54 80 63 82 / 0 0 0 0
Brownsville 55 82 63 82 / 0 0 0 0
Harlingen 52 83 60 85 / 0 0 0 0
McAllen 55 85 61 87 / 0 0 0 0
Rio Grande City 52 88 59 89 / 0 0 0 0
South Padre Island 61 76 66 75 / 0 0 0 0

&&

Bro watches/warnings/advisories...
Texas...none.
GM...none.
&&

$$

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67...shortterm
59...long term
65...graphics

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