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Area forecast discussion 
National Weather Service Houston/Galveston Texas
1000 am CDT Thursday Apr 24 2014

Discussion...
showers and thunderstorms from around College Station to Katy to
Sugarland will continue to race off to the east and should weaken
along the south end but north end may intensify with the
increasing instability and weaker cap. Impressive cloud/no cloud
boundary can be seen to the west out ahead of the cold front
(which is really kicking up the dust per vis) as the front nears
the cll area late this afternoon/early evening will see increased
threat for stronger thunderstorms with gusty winds. Updated the
forecast to raise probability of precipitation this morning and afternoon and to adjust
sky grids.
45

&&

Previous discussion... /issued 447 am CDT Thursday Apr 24 2014/

Discussion...
a tight onshore pressure gradient...created by surface low
pressure troughing over the Texas/OK panhandles and high pressure
settled over Florida...has kept southerlies up through the night.
Thus...no fog issues this morning with only low stratus within
this mild and more humid regional air mass. Another day of onshore
flow will keep moisture levels high while daily cloud breaks
allow many to warm into the average lower to middle 80s. The
passage of an afternoon Southern Plains shortwave trough may
initiate northern Texas convection and this activity may clip the
north-northeastern County Warning Area latter today. In the lower levels...focus
is provided by the passage of a weak boundary within a humid and
conditionally-unstable downstream environment. The eastern
movement of this boundary/shortwave trough may pull the dry-line
boundary far enough east to allow discrete cell storms (firing up
along it) to maintain their integrity long enough to affect our
far northeastern County Warning Area. The upper levels do not appear favorable for
sustaining significant convection...therefore slight chance probability of precipitation
over the far interior to communicate this low risk for any late
day convection.

The lower Continental U.S. Will fall under a near-zonal flow from Friday
into early next week. Onshore winds will maintain ample humidity
with subsequent day warming into the mean upper 80s by Sunday or
Monday. Models are still prognosticating a deepening Great Basin
upper trough this weekend...having it enter the Western Plains as
a near 540 dam closed-off low Sunday. The southern extension of
its trough axis will be entering western Texas late Sunday and
generally allowing it to lay over the state through mid-week. This
broad mid-U.S. Troughing pattern will allow a couple of lobes of
northern plains energy to fall into it...rotating around its base
and assisting in pushing a relatively strong cold front through
the region Tuesday. Higher rain chances of slight to low chance
for showers and isolated storms Sunday and Monday as East Texas
falls under a warm air advection pattern downstream of this
developing cold front. The air mass that will be spilling down
into Texas will be Continental in nature...near 20c 85 temperatures early
Tuesday will significantly cool down into the single digits by
late Wednesday. After several days of morning 60s/afternoon 80s...
temperatures will cool down by a good 15 degrees or so on temperature extremes.

So...the general late week and weekend theme will be partially cloudy
.Warm and humid...With the daily slight chance of a passing shower
or rogue storm. This pattern will undergo significant change from
Tuesday into Wednesday...the last couple days of the month. A progressive
cold frontal passage and the backing cold and dry air mass will pack
quite the punch...lowering diurnal temperatures/rhs down to below normal. 31

Aviation...
winds have remaining up tonight keeping visbys up but some MVFR
ceilings. Expect them to gradually rise into VFR territory 15-17z and
remain that way for the remainder of the day. A weak frontal
boundary will move close to northern parts of southeast Texas late in the afternoon.
Warm layer of air aloft (cap) will be limiting factor for thunderstorms
for all of southeast Texas...but locations north of Brenham-Livingston line
would be the place where its strength to be the weakest and will
need to keep an eye up there 21-02z should it break as it'll be
quite unstable otherwise. Plan on leaving vcts's in place for
uts/cll. 47

Marine...
moderate onshore flow will gradually diminish today as a weak
frontal boundary moves into northern parts of southeast Texas. Winds will be
light overnight...and a brief wind shift to the north is expected
toward sunrise Friday in association west/ a land breeze. Onshore winds
will quickly resume during the afternoon and increase (along west/ seas)
through the weekend as the pressure gradient tightens. Will probably
need caution/advsy flags by Sat night. 47

&&

Preliminary point temps/pops...
College Station (cll) 85 62 85 64 86 / 30 10 10 10 20
Houston (iah) 84 65 85 63 85 / 20 10 10 10 20
Galveston (gls) 78 68 77 70 80 / 10 10 10 10 20

&&

Hgx watches/warnings/advisories...
Texas...none.
GM...none.
&&

$$

Discussion...45