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Area forecast discussion
National Weather Service Houston/Galveston Texas
947 PM CDT Mon may 22 2017

all rainfall has diminished across southeast Texas as of 9:30 PM. Latest
models are showing a lull in the activity during the remainder of
tonight except for off the coast due to a frontal boundary in the
Gulf. The front should continue to be a focus for rain chances in
the Gulf waters. If the Texas tech and nam12 pan out, the next
chances for showers and thunderstorms over the land areas will be
during the mid afternoon lasting into the evening.

Lowered rain chances for tonight and for Thursday morning.



Previous discussion... /issued 656 PM CDT Mon may 22 2017/

break in the showers and thunderstorms for most of the evening
into tomorrow morning across almost all taf sites. Gls has a few
showers within its vicinity currently, but those should move over
the near shore waters within the next hour. Currently, winds are
out of the north northeast. Model guidance is picking up on lower
visibilities across cll, lbx and possibly cxo, sgr, and uts in
the early morning hours. With a saturated surface and possible
radiational cooling, not completely impossible but there will be
some lingering cloud cover that could also help to keep the
surface warmer.

Next best chance for precip moves in with the cold front into cll
around 21z Tuesday, and scoots southward through the day. Expect
most sites to see precip between the 21-00z time period out ahead
of the cold front. Winds will stay out of the north as the front
passes as well, and will pick up in speed behind the boundary.


Previous discussion... /issued 347 PM CDT Mon may 22 2017/

Short term (tonight through Tuesday night)...
surface analysis this afternoon showed a remnant boundary/ cold
front stretching from near La Ward to south of Houston hobby
Airport to Winnie, with scattered showers developing along this
boundary as it moves southeast towards the coast. Expect the
boundary to continue propagating towards the coast as mid and
upper level flow becomes increasingly perpendicular to the
boundary as a shortwave trough lifts away from East Texas.
Subsidence and mid-level dry air advection behind the shortwave
should help limit rain chances tonight after the frontal boundary
clears the coast this evening, but may not entirely prevent a
possible thunderstorm complex advertised in high resolution
guidance from clipping parts of the Brazos Valley or Piney Woods
region as it moves out of West Texas tonight and weakens.
Additionally, an 80-100 knot upper level jet nosing over the
region will mean that a few showers and maybe a thunderstorm will
remain possible. Not entirely confident on any activity developing
or the West Texas thunderstorm complex reaching the region (hence
20 pops north of the coast) but if something is able to develop or
reach the region, cannot rule out some small hail as lapse rates
steepen to nearly 7.5 c/km and the mid-levels of the atmosphere
dry behind today's shortwave. Otherwise, expect overnight lows in
the 60s to low 70s under mostly cloudy skies.

A second shortwave now moving over the Texas and Oklahoma
panhandles on afternoon water vapor imagery will continue to swing
southeast across Texas tonight, reaching the region during the day
tomorrow. This will send another cold front across the region
during the day Tuesday and off the coast Tuesday night, with
scattered showers and thunderstorms developing along and behind
the front as it moves south. The passage of today's frontal
boundary won't completely scour out the moisture in place across
the region tomorrow as precipitable water values remain in the
1.4-1.5 inch range, but slightly less moisture should result in
a lower (but not nonexistent) locally heavy rain threat than
today. Additionally, an inverted-v signature on forecast soundings
out of Houston and steep mid- level lapse rates persisting mean
that a few thunderstorms along the front tomorrow may also become
strong to severe and capable of gusty winds and hail. Best chances
for this appear to be along and east of Interstate 45 during the
afternoon hours, especially if breaks in the clouds during the
morning contribute to additional destabilization. Afternoon
temperatures on Tuesday are forecast to rise into the mid 70s to
mid 80s.

Expect the cold front to push off the coast Tuesday night with
rain chances tapering off form north to south as drier air filters
in behind the front, with lows Tuesday night in the mid 50s to mid


Long term (wednesday through sunday)...
north to northwest flow aloft on Wednesday is expected to
gradually transition to shortwave ridging through the end of the
work week, resulting in drier and gradually warming conditions as
highs climb back near 90 by Friday. Shortwave ridging becomes
dampened over the upcoming weekend as a shortwave trough dives
across The Four Corners. Rain chances increase for the region late
week into the beginning of next week as the passage of this
shortwave trough sends a cold front into the region.


elevated winds and seas will gradually come down later this
afternoon and on into this evening. Periods of mainly scattered
showers and thunderstorms remain possible through Tuesday as
frontal boundaries and a series of disturbances move across the
area. Stronger/deeper northerly winds will not make it into the
Gulf until Tuesday night/ Wednesday morning, and caution flags
might be needed during this time. Onshore winds are set to return
to the area by Wednesday night and then strengthen the rest of the
week and on into the weekend. 42


Preliminary point temps/pops...
College Station (cll) 64 80 56 81 61 / 10 50 30 10 0
Houston (iah) 67 83 60 83 63 / 20 40 40 10 0
Galveston (gls) 73 81 67 81 73 / 40 40 40 10 0


Hgx watches/warnings/advisories...

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