Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
FXUS64 KHGX 192042
Area Forecast Discussion
National Weather Service Houston/Galveston TX
342 PM CDT Wed Oct 19 2016
The primary forecast issue will be the timing of this frontal
passage and the anticipation (at least, to some) of significantly
drier and cooler air. Before the front, we can look for more fog
development tonight in the moist airmass. After a cooler weekend,
we should see a gradual warmup into early next week along with an
increase in humidity. Along with the return of hotter, more humid
weather, will come some small potential for rain, but likely
scattered showers/storms at best.
Tonight through Saturday...
One last warm night, while the well-advertised cold front lurks
back in Oklahoma per mesoanalysis. Skies should also be clear
enough and winds light enough to allow for fog development again
today. At this time, expect something similar to this morning,
with areas of fog ringing the Houston metro to the west and north,
with patchy fog expected elsewhere. It`s probably not out of the
question for some dense fog, but will also have to weigh that
against the arrival of a pre-frontal trough and some possible wind
associated with that, so will be a little conservative for now.
The front looks to be late enough that Thursday should still be
pretty warm, but blunted a bit to provide some limited relief.
Along with that, we`re looking for some potential rain both a
little early from the pre-frontal trough and again along the
front. Despite its Ralph Wiggum meme reputation, actually think
the NAM is on to something in having broken precipitation
associated with the front, which is also reflected in the TTU WRF
as well, so will limit PoPs to high chance. Even more extreme, if
the NCAR WRF ensemble is to be believed, things look to be
even drier than what is forecast.
Behind the front, cold air advection begins in earnest under
northerly winds, and place well inland may see lows dip into the
upper 40s Friday night. On Saturday, winds will begin to shift
onshore again while weak upper ridging works to return to South
Texas, so expect Saturday to be the end of cold air advection,
with temps comparable to or even a bit warmer than Friday.
Late weekend into early next week...
The weekend looks to continue its gorgeous weather with
temperatures not far below seasonal averages and nil precip
potential. However, due to the aforementioned setup, we should see
a gradual warming trend over those next few days. Humidity should
also be climbing, and as column moisture increases, we can also
look to see the return of isolated/scattered diurnal convection.
It`s beyond the scope of the current forecast, but both the Euro
and GFS dig a cut-off low aloft late in the week, so that may be
something to watch for. Of course, as is standard at such ranges,
there is significant difference in the evolution of this pattern
and the NAEFS percentiles also do not yet provide any confidence
into how this might play out.
Onshore flow of 9-13 knots will prevail early this evening before
gradually relaxing tomorrow morning. Cold front marches south and
should be preceeded by a prefrontal trough/ridging that backs winds
to the northeast but mainly less than 10 knots. The cold front
should cross into the coastal waters in the evening hours and bring
Small Craft Advisory conditions with sustained winds of 20-25 knots
and seas building to 7-9 feet. Winds should gradually diminish as
high pressure builds into the region with 1021mb ridge over SETX by
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 70 81 52 77 51 / 30 40 10 0 0
Houston (IAH) 72 85 56 79 52 / 20 40 10 0 0
Galveston (GLS) 78 83 67 76 64 / 30 50 10 0 0