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Area forecast discussion 
National Weather Service Houston/Galveston Texas
251 PM CDT Tuesday Jul 7 2015

Discussion...
radar showing scattered showers this afternoon...and a few
lightning strikes with pulse storms moving quickly north with
southerly flow. Should see this convection diminish late this
afternoon with loss of daytime heating. Cant rule out an isolated
streamer shower coming off the Gulf overnight...as occurred last
night...but should again be limited as far as coverage.

For Wednesday and Thursday...airmass not as moist as today as
indicated by lower precipitable water values in the models moving
over the area. Model soundings also show this drier air off the
surface and a weak capping inversion so think tomorrow will be
mainly dry during the day Wednesday and Thursday. Should remain
hot and humid although afternoon dewpoints will likely be a few
degrees lower than today given possibility of mixing some of the
drier air aloft down to surface.

For Friday through the weekend...mean layer moisture begins to
increase again but not expecting any more than 20 to 30 percent
coverage with mostly dirunal convection...morning at coast...and
afternoon inland...much like we have today. Not a wash out by any
means. Coverage inhibited by ridging aloft and at surface. 46



&&

Marine...
the 1020 mb high centered over Florida is creating a tight enough
onshore pressure gradient...in relation to a Western Plains
trough...to generate a more moderate southerly wind. The presence of
a low level jet may also be a contributor to the overnight
strengthening of onshore winds as these stronger winds mix down to
the water's surface. Small craft exercise caution flags will remain
up in the short term to account for these near 15 knot Gulf winds...
responding elevated seas that will generally range from 3 to 4 feet
nearshore...4 to 5 feet across the far offshore waters. Eastern high
pressure will expand further west at week's close and weaken onshore
winds...lower seas through the upcoming weekend. 31

$$

Aviation...
primarily VFR conditions...re-emergence of an early morning/dawn
low level jet out west may (re)introduce short lived MVFR decks over more
western hubs early Wednesday am. Today...a thickened cumulus field with
a sea breeze lifting off the coast as inland temperatures achieve
90f...occasional passing showers too random to place within 18z
tafs. A drier air mass advecting in from the south should aid in
just keeping a few cumulus deck around tomorrow...slight to low rain
shower chances. 31

&&





Preliminary point temps/pops...
College Station (cll) 77 94 76 93 74 / 0 10 10 10 10
Houston (iah) 78 94 76 92 75 / 0 10 10 10 10
Galveston (gls) 81 90 81 89 80 / 10 10 10 10 10

&&

Hgx watches/warnings/advisories...
Texas...none.
GM...small craft should exercise caution through Wednesday morning
for the following zones: waters from Freeport to the
Matagorda Ship Channel 20 nm to 60 nm...waters from
Freeport to the Matagorda Ship Channel out 20 nm...waters
from High Island to Freeport 20 to 60 nm...waters from High
Island to Freeport out 20 nm.

&&

$$

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