Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
FXUS64 KHGX 311546
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1046 AM CDT Wed Aug 31 2016
Another mostly sunny and warm morning is underway for Southeast
Texas, with 10 AM temperatures in the mid 80s across the region.
Morning water vapor imagery showed an upper level disturbance
located near the Lower Texas Coast and this feature is expected to
continue to drop south of the region through the day as upper
ridging spreads farther west into the Southern Plains from the
Mid-Mississippi Valley. Drier air associated with this ridge can
be seen moving towards the forecast area on CIRA layer
precipitable water imagery (LPWs less than 1.5 inches over
northeastern Texas) and loss of support from the departing upper
level disturbance combined with drier air will result in lower
rain chances today than the past few days.
The main forecast update was to lower rain chances to 20 percent
across most of the region as a result. Also extended mention of
isolated showers and thunderstorms across the Gulf waters where
some weak forcing may remain, near the upper disturbance. No other
changes were made to the forecast, with high temperatures climbing
into the low to mid 90s today.
.PREV DISCUSSION... /ISSUED /
12Z TAF DISCUSSION...Radar shows a few showers by KGLS this
morning which should track towards KLBX. Most terminals have VFR
conditions with KCLL/KCXO/KUTS having some patchy fog and
visibility down to 4 to 6 SM. Fog should be short lived and expect
another day with NE/E winds and high based cumulus. There may be
enough moisture and day time heating to produce isolated shower
activity so included VCSH for most TAFs in the afternoon. VFR
conditions expected overnight with again some patchy fog.
Bit of a complex flow pattern was located over Texas and the Gulf
of Mexico. An upper low was just off the lower Texas coast while
an upper level ridge centered over the mid Mississippi Valley
stretched across the northern part of the state. A weak shortwave
ridge was located over the central Gulf of Mexico while TD Nine
was situated over the southeastern Gulf.
A couple of favored areas of convection have developed early this
morning. The first was between Montgomery to Caldwell with the
other along and just off the coast. Brief heavy downpours will be
possible with the stronger storms. The HRRR model forecast shows
these showers and storms diminishing between 7 and 9 AM. The high
resolution models then bring isolated showers and thunderstorms
back into the picture mainly after 2 PM this afternoon. These in
turn should diminish around or shortly after sunset this evening.
Over the next few days the model solutions show the upper low over
the lower Texas coast shearing out and moving south as the upper
level ridge recenters itself over the plains and over the central
and western parts of the state. TD Nine is expected to move toward
the northwestern coast of Florida. The developing northerly flow
at the surface and aloft will help push a backdoor cold front
southward through the Plains and Mississippi Valley. The results
will be hot and humid conditions over SE Texas with isolated
chances for showers and thunderstorms today and Thursday. Better
chances for rain will accompany the front on Friday and Saturday.
A deep layer southeasterly flow will then help keep scattered
thunderstorms chances in place through the Labor Day holiday and
NE to E winds will continue today and persist through the end of
the week. TD 9 continues to churn over the south central Gulf and
could become a tropical storm today. Wind shear has weakened over
the system and convection has become more robust overnight. TD 9
will likely support higher period swells of a couple feet through
the end of the week. Overall expect seas in offshore areas of the
Upper Texas Coast to be in the 3 to 5 foot range today and
tomorrow. Seas should decrease for the end of the week and into
the weekend with light winds.
This morning tide levels are about 1 ft above normal headed into
high tide along the Upper Texas Coast. This will put tide levels
about 2.8 to 3 feet above MLLW along Gulf facing beaches during high
tide. This may cause some very minor coastal flooding along Bolivar
Peninsula but more than likely not cause problems. Tide levels
should be decreasing the next few days.
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 95 76 95 75 92 / 20 10 20 20 30
Houston (IAH) 94 76 96 76 92 / 20 10 20 20 30
Galveston (GLS) 91 81 92 80 89 / 20 10 20 20 30