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Area forecast discussion 
National Weather Service Houston/Galveston Texas
1252 PM CDT Sat Aug 30 2014

18z aviation discussion below.


although the majority of today's convection has remained offshore
..more discrete cells are beginning to develop inland as middle 80f
convective temperatures are met within this humid air mass. Southern
hub vcsh is certainly warranted during the warmth of the day...primarily
VFR decks with the occansional lowering to high end MVFR. A lull in
overnight interior precipitation with areawide ceilings lowering to
more frequent MVFR...periodic and brief IFR. Moderate chance for vicinity
rain with isolated storms to impact near coastal terminals from around
sunrise on through middle-Sunday afternoon. Wind field will be light
and variable...the dominant S-southeast direction with sub 12kt winds. 31


Previous discussion... /issued 1032 am CDT Sat Aug 30 2014/

see morning update.

at 14z...a weak trough of low pressure extended from north central
Louisiana S-SW across the Upper Texas coast to a weak area of low
pressure over northern Mexico. At 850 mb...abundant moisture lingered
over East Texas with an 850 mb trough axis oriented north to south
from western Arkansas to the western Gulf. 700 mb moisture was also
widespread from Texas to Mississippi with a weak trough axis noted
from eastern Oklahoma to Palacios and then out over the Gulf. A
500 mb trough axis lingered over East Texas. At 250 mb...a well
defined trough axis extended from the Central Plains into central
Texas. A 55 knots speed maximum extended into East Texas but southeast Texas looks
to be in the subsident region of the speed maximum with the best lift
focused over the western Gulf. 12z soundings show rich tropical
air in place with precipitable water values between 2.4 and 2.6 inches. Convective
temperatures range from about 84 to 88 degrees across the area and this
threshold should be met later this afternoon. Short term models
keep things dry this afternoon but with southeast lying to the east of
the 500 mb trough axis...low convective temperatures and deep tropical
moisture in place...feel at least scattered rain showers/thunderstorms and rain will develop
later today. Temperature forecast looks on track as does sky cover. New zones
out by 1045 am.

Small changes to the marine zones as well. Issued a scec for
marine area as winds are around 16 kts with seas of 4 feet. Much
of this is the by product of convection and winds/seas will begin
to subside once convection weakens and moves east. 43


Previous discussion... /issued 652 am CDT Sat Aug 30 2014/

see aviation for 12z taf discussion.

expect scattered showers and thunderstorms to persist along the
coast and offshore through the taf period. Inland coverage and
northward extent of convection remains somewhat difficult. Most
inland sites should remain dry through late morning with cll/uts
least likely to see any activity at all. Aside from convection
expecting VFR conditions to prevail for much of the current taf
period once ceilings begin to improve by middle morning. 38


Preliminary point temps/pops...
College Station (cll) 74 94 76 95 76 / 20 30 10 20 10
Houston (iah) 76 92 77 93 77 / 50 50 10 30 10
Galveston (gls) 80 89 81 90 81 / 50 50 10 30 10


Hgx watches/warnings/advisories...
GM...small craft should exercise caution until 4 PM CDT this
afternoon for the following zones: waters from Freeport to
the Matagorda Ship Channel 20 nm to 60 nm...waters from
Freeport to the Matagorda Ship Channel out 20 nm...waters
from High Island to Freeport 20 to 60 nm...waters from High
Island to Freeport out 20 nm.




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