National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS64 KHGX 200237
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
937 PM CDT Wed Sep 19 2018

.UPDATE...
Tweaked temperatures a bit to lower low temps tonight in some of
the more rural areas and expanded the patchy fog a bit. Looks like
a quiet night on tap for the area.

11

&&

.PREV DISCUSSION... /ISSUED 334 PM CDT Wed Sep 19 2018/

DISCUSSION...
Isolated showers trying to develop over Houston county this
afternoon and with the remain hour or two of peak heating may just
squeeze out a slow moving storm north and east of Lake Livingston.
In addition storms over Jasper should continue to develop this
time period and could add an outflow to the mix if it makes it
into the eastern counties.

Skies should quickly clear out again tonight with a gradual
increase in low level moisture over the coastal counties and over
the Gulf. Expecting isolated to widely scattered showers mainly
after midnight over the Gulf and can`t rule out one moving into
the immediate coast toward morning. During the day Thursday with
mid levels slowly moistening as well and daytime heating may see a
few showers and thunderstorms dotting the area and along the
seabreeze though weak capping may remain present throughout the
day.

Friday rain chances ramp up as layer RH gets much greater and PW
climb solidly above 1.9" possibly nearing 2.2" by afternoon. Model
soundings support scattered potential across the region. The
forecast gets tricky this weekend with a cold front pushing down
into the state and by Saturday morning could be pulling up over
FTW to near SAT area with a string of weak short waves rippling
over SETX and persistent low pressure trough over Central TX.
Timing for storms at this point looks like Saturday morning south
and coastal waters then shifting inland during the afternoon. Late
Saturday afternoon and Saturday night mesoscale boundaries to the
west and northwest could play havoc with the forecast and
although the POPs are fairly high with the package they may need
bumping up further if convection to the west gets more
progressive. Brief heavy rainfall possible Saturday and Sunday.
Sunday the environment is primed but uncertainty is on the
increase thanks in large part to the frontal boundary movement and
upper low over the Gulf and how strong upper ridging may be near
the coast. Trended the forecast for Monday-Wednesday toward the
ECMWF solution which should keep a decent shot at rain each day.
Even better is the possibility that a cold front...a real
September cold front with dry air should be headed toward SETX
Wednesday night or Thursday next week. GFS is probably too bullish
with the cold front and ECMWF may be better with timing which
would favor the FROPA on Thursday.

45

MARINE...

Expect a continuation of light winds and low seas through today with
increasing winds through tonight into tomorrow as low pressure
develops over Colorado. Shower activity may be more abundant
tomorrow morning than this morning. Seas will be a little slower to
respond, increasing to around three feet by early Friday morning.

Moisture associate with what, once upon a time, was associated with
Isaac will begin to work its way into the region for the end of the
week, with thunderstorm activity increasing Friday and carrying
through the weekend. Winds and waves may be locally higher near any
storms. Tides may run half a foot or slightly higher above
astronomical levels, but at this time are expected to stay near or
below 2.5 feet MLLW.

Luchs

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      74  90  75  88  76 /   0  30  40  60  50
Houston (IAH)              78  89  78  87  77 /  10  20  40  70  50
Galveston (GLS)            81  86  81  85  80 /  10  30  30  60  50

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...11