Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
FXUS64 KHGX 240239
Area Forecast Discussion
National Weather Service Houston/Galveston TX
939 PM CDT Sun Apr 23 2017
Another night of clear skies and cool low temperatures as
offshore flow continues to keep dewpoints depressed. Did tweak
temps a little bit for observations, which resulted in a slight
nudge up for forecast lows - however, the difference is likely
negligible as far as sensible impacts go.
.PREV DISCUSSION... /ISSUED 620 PM CDT Sun Apr 23 2017/
SKC and diminishing north winds overnight. SKC tomorrow with winds
coming back around to the south around 5-7 knots in the afternoon.
Could see possible low cloud and fog formation Monday night into
Tuesday morning as light south winds persist. 42
PREV DISCUSSION... /ISSUED 304 PM CDT Sun Apr 23 2017/
The surface high over central Texas has helped relax the surface
pressure gradient. Clear skies and light winds will affect the
area tonight and Monday as an upper level shortwave ridge moves
across the state. Do expect onshore winds to resume by late in the
day on Monday as the surface high moves east of the area.
The remainder of the week will see a rise in temperatures and an
increase in Gulf moisture overhead as an upper level trough
deepens over the plains and southern Rockies. More of a shortwave
trough will first move into the Rockies on Tuesday and the plains
and Texas on Wednesday. This trough should drive a cold front into
SE Texas; although, the GFS and ECMWF do differ a bit on how far
to the coast, or off the coast, the front will travel. Either way,
onshore winds will quickly return by Thursday evening. A stronger
and more of a long wave upper level trough will then develop over
the southern Rockies Friday with an upper low forming over AZ or
NM early on Saturday. This system will move into the plains over
the weekend. Still some model disagreement on the coverage and
timing over the weekend. Tried to take a blend which shows better
coverage over the north on Saturday and east on Sunday.
Moderate offshore flow will gradually diminish this evening before
becoming onshore tomorrow. Small craft should exercise caution in
the Gulf waters this evening. Onshore flow will strengthen through
midweek as a cold front approaches, and caution or advisory flags
may be required Tuesday or Wednesday. A cold front may push off the
coast Wednesday but is expected to be fairly weak.
Onshore flow will resume once again Thursday before strengthening
Friday and into the weekend as the gradient tightens in response to
a developing system over the high plains. Caution or advisory flags
may be needed again to start out the weekend. Another (probably more
substantial) cold front is forecast to push off the coast sometime
around Saturday night/Sunday with gusty offshore flow and building
seas in its wake.
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 49 79 60 86 71 / 0 0 0 10 10
Houston (IAH) 52 81 62 84 72 / 0 0 0 10 10
Galveston (GLS) 62 76 70 79 75 / 0 0 0 10 10
GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 10 PM CDT this evening
for the following zones: Coastal waters from Freeport to
the Matagorda Ship Channel out 20 NM...Coastal waters from
High Island to Freeport out 20 NM...Waters from Freeport to
the Matagorda Ship Channel from 20 to 60 NM...Waters from
High Island to Freeport from 20 to 60 NM.