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Area forecast discussion 
National Weather Service Houston/Galveston Texas
301 PM CDT Monday Mar 30 2015

another nice Spring day across southeast Texas with temperatures
in the upper 70s to lower 80s under partly cloudy skies. Mostly
clear skies are expected this evening with low clouds redeveloping
late tonight and lingering through Tuesday morning. Precipitable water values are
prognosticated to fall below an inch on Tuesday with a very dry layer
noted at 850 mb and a strong cap in place. The drier air aloft
will mix to the surface so partly cloudy skies are expected by
afternoon. A short wave trough will approach on Wednesday. This
feature is a bit slower than prognosticated yesterday and will approach
southeast Texas during the late morning. High pressure over the central Gulf
at 850 mb will gradually move east but it appears that this
feature will remain close enough to force the shortwave to the northwest and
around the periphery of the 850 mb high. Will taper probability of precipitation highest
west and lower toward the coast on Wednesday. Global models in
better agreement today with timing...quantitative precipitation forecast and probability of precipitation. Precipitable water values will
increase to 1.4 to 1.6 inches by 18z Wednesday. The NAM 12 forecast
soundings show cape values between 1500-2000 j/kg on Wednesday afternoon with
Li values -5 to -8 and fairly steep lapse rates. Jet dynamics not
looking too impressive but other instability parameters support
the possibility of some strong storms during the afternoon over the northwest
half of the region. The European model (ecmwf) and Canadian keep rain chances going
through Thursday morning but think subsidence will dominate in the
wake of the shortwave. Will maintain slight rain chances through
Thursday morning just in case the ec/can are on the right track.

Warm and humid conditions will prevail Thursday/Friday in the wake of the
short wave and 850 mb temperatures really warm up by Friday. Would not
be surprised if temperatures on Friday reach the upper 80s but for now
have trended warmer but feel cloud cover might linger through middle
afternoon negating the warmer temperatures aloft.

A cold front will cross southeast Texas Friday night with scattered showers
expected along the front. Global models are in good agreement
with the timing/strength of the front. Considerably cooler
temperatures are expected on Saturday in the wake of the front.
Another upper level disturbance will move across southeast Texas on Sunday
and this feature will generate more rain for southeast Texas.


the western expansion of the Florida-centered surface ridge has
weakened the pressure gradient enough to lower onshore winds to
under 10 kts...keeping swell/sea heights to 4 feet and under today.
Near 10 knots onshore winds Tuesday will maintain a 2 to 3 foot Gulf
wave height with relatively smooth Bay waters. A passing upper level
disturbance at middle week will keep moderate rain chances alive
through the daytime hours Wednesday. The next cold front is timed to
travel across the Gulf early Saturday morning. The forecast is for a
short fuse advisory conditions to cover near 20 knots sustained
Saturday morning winds. 31


Preliminary point temps/pops...
College Station (cll) 62 82 63 79 64 / 10 10 10 50 20
Houston (iah) 61 83 64 80 66 / 10 10 10 40 20
Galveston (gls) 64 77 66 76 68 / 10 10 10 40 20


Hgx watches/warnings/advisories...


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