Scientific Forecaster Discussion
fxus64 khgx 131022
Area forecast discussion
National Weather Service Houston/Galveston Texas
422 am CST Wed Nov 13 2019
Short term (today through thursday)...
Mid/upper low currently situated just east of baja will continue
making its way toward the region. Expect a gradual increase of
cloudiness moving into the area from the southwest today as this
occurs. Though there may be some returns on radar early in the day
as leading impulses move thru, a very dry subcloud layer should
allow most precip to evaporate before reaching the ground (virga).
As we head into the afternoon and evening hours, the drier air
will slowly erode as the moisture column becomes increasingly
saturated from top down and allow for more favorable chances of
some -ra reaching the surface.
Rain should fill in across much of the area later tonight and
Thursday as the trof makes its way eastward across the region.
Light/moderate stratiform rain should prevail, though we did throw
in the mention of isolated tstms well offshore closer to where
better llvl convergence associated with the coastal trof should be
located. Nudged fcst highs down several degrees on thurs as
rainfall/clouds should limit much in the way of heating. Precip
should taper off NW-to-se late in the period as the system pushes
off to the east and a reinforcing cold front moves in behind it.
Long term (thursday night though wednesday)
The upper trough will be exiting off to the northeast with its
axis across Louisiana by midnight Friday. This will introduce
moderate northerly mid to upper flow to eastern Texas Friday. A
drier air mass will advect in over the region behind a surface
front and fortify already (relatively) dry conditions heading into
the weekend. Overcast Thursday night skies will clear from north
to south to partially cloudy through Friday morning. North breezes
and mostly cloudy at sunrise will govern temperatures from falling
much below the middle 30s inland / mid to upper 40s coastal. More
sun with a drier atmosphere Friday afternoon will have temperatures
climbing into the mid to upper 50s by 1 or 2 PM.
Upper ridging moves across through Saturday with subsequent
warming each afternoon through the remainder of the period...near
60 f maximum temperatures on Saturday will gradually warm back
into the average lower to middle 70s next Wednesday. Clearer
skies and a weaker northeast breeze will allow overnight ambient
temperatures to fall closer to their respective dewpoints; inland
low to mid 30s / coastal mid to upper 40s at sunrise Saturday
with a subtle warm up Sunday morning due to breezes returning from
the Gulf. The next chance for rain will be late Sunday into
Monday morning as a fairly deep upper trough travels across
eastern Texas. Increasing Sunday cloudiness and a decent onshore
flow will provide more humidity and warmth into the low to mid
60s. A somewhat similar weather pattern to tomorrow's in that a
surface low/inverted trough will move up the Upper Texas
coastline... precipitation will begin as early as Sunday afternoon
out west with the bulk of the rain occurring over the maritime
during the overnight late Sunday through Monday morning hours.
Inland light rain or even drizzle at times / showery weather in
association with this early week trough due primarily in part to
the lack of sufficient moisture...onshore winds will not have
enough time on Sunday to increase pwats up to where they should be
in producing higher rain accumulations. So, slight to low end
chances for low quantitative precipitation forecast in the form of light rain and/or showers.
The area falls under a dry northwest mid-upper wind pattern on
Monday through Wednesday. Quiet (a.K.A. Clear and dry) early work
week weather with chilly mornings and mild days becoming less
chilly and mild...40s/60s on Monday transition to 50s/70s on
Winds/seas continue to diminish...though will need caution flags
beyond 20nm for a few more hours until seas drop below 6 ft.
Periods of rain and isolated tstms can be expected later tonight
as the next upper level storm system approaches from the west.
The pressure gradient will tighten as a coastal trof develops in
advance...east winds increase and seas build. Will likely need to
hoist caution/advsy flags again after midnight. Winds will
eventually back to the NE then N thru the day system moves thru
and a reinforcing front moves in behind it. Small craft advisories
will probably be required through late Friday morning until winds
and seas begin to diminish. Light onshore winds will briefly
resume early Sunday, but expect another front to push off the
coast Sunday night with moderate to strong NW/N winds in its wake.
VFR conditions are expected most of the daylight hours at the
terminals, but do expect lowering high & mid level ceilings. They
should continue falling tonight...eventually into MVFR and
possibly IFR territory later tonight as rainfall from the next
storm system moves into the region. 47
Preliminary point temps/pops...
College Station (cll) 48 38 46 34 58 / 20 70 70 10 0
Houston (iah) 47 39 47 38 58 / 10 80 80 20 0
Galveston (gls) 51 47 53 46 57 / 10 90 80 30 0
Texas...hard freeze warning until 8 am CST this morning for the
following zones: Grimes...Houston...Madison...Montgomery...
Freeze warning until 9 am CST this morning for the following
zones: Chambers...coastal Brazoria...coastal Galveston...
coastal Harris...coastal Jackson...coastal Matagorda...Fort
Bend...inland Brazoria...inland Galveston...inland Harris...
inland Jackson...inland Matagorda...northern Liberty...
GM...small craft should exercise caution until 4 am CST early this
morning for the following zones: coastal waters from
Freeport to Matagorda Ship Channel Texas out 20 nm...coastal
waters from High Island to Freeport Texas out 20 nm.
Small craft should exercise caution until 6 am CST early this
morning for the following zones: waters from Freeport to
Matagorda Ship Channel Texas from 20 to 60 nm...waters from
High Island to Freeport Texas from 20 to 60 nm.