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Area forecast discussion 
National Weather Service Houston/Galveston Texas
958 PM CST Thursday Feb 26 2015

Discussion...
cold front offshore and winds have picked up across the coastal
areas. Trends showing that temperatures and dewpoints needed lowering and
have expanded the next two tiers of counties southward to include
Conroe in freezing temperatures tonight. Skies are a mixed bag
with band of SC across the eastern and portions of the central
counties but with more widespread ceilings just to the northwest. As
these clouds expand overnight it should slow the temperature fall
especially after 2 or 3 am. Also lowered rain chances in the Gulf
in the morning but by early afternoon a few sprinkles may be in
order.

45
&&

Previous discussion... /issued 546 PM CST Thursday Feb 26 2015/

Discussion...

See aviation.

Aviation...

Patch of MVFR strato cumulus is moving southeast across northern areas.
Expect additional strato cumulus to form this evening with widespread
MVFR ceilings then persisting tonight and into most of tomorrow
morning. North/NE winds will stay up in the 10-15 knots range (higher
along the coast) tonight due to the tight pressure gradient that
exists behind the frontal boundary that moved through earlier
today. 33

Previous discussion... /issued 320 PM CST Thursday Feb 26 2015/

Discussion...
the cold airmass overhead of the area will move eastward by
Saturday. This will lead to a warming trend over the weekend and
into next week. This is indicated by the GFS 5-wave 500 mb
forecast showing increasing heights for the first half of next
week across southeast Texas as a ridge builds over Central America.
However...a long wave trough will linger over the plains and lead
to an unsettled weather pattern late Friday through Wednesday.

The chilly...below normal temperatures will persist for the next
couple of days across southeast Texas. Although there were clearing
conditions in place over many locations this afternoon...do expect
clouds to overspread most areas tonight. The timing of the
arrival of clouds will help determine the overnight low
temperatures. For now leaned toward the cooler mav guidance.
Although isentropic lift will aid in cloud development Friday
night...most inland locations will again see overnight lows in the
30s.

Regarding the rainfall potential...the models differed a bit for
Friday and Saturday. Decided to take a blend of the model
solutions both days. Sunday may see a warm front move well inland
per the European model (ecmwf) or into the northern counties per the nam12. Because
of the uncertainty...took a blend of the model solutions. A decent
shortwave trough moving through the flow aloft should allow for at
least isolated thunderstorm development on Sunday. Both the GFS
and European model (ecmwf) differ more on a cold frontal dropping into the area
Monday or Tuesday. Both push the front off the coast late on
Wednesday.

40

Marine...
still anticipate a slight increase in winds/seas offshore this
evening and will maintain current flag configuration (caution
nearshore & advsy offshore). Winds will veer to the northeast and
east Friday and Sat and increase in speed. Building seas & surf,
higher tide levels and heightened threat of rip currents will
result this weekend. Small craft advisories will be required. Some
uncertainty if a warm front will move inland Sunday or hold off
until Sunday night or Monday. Previous forecast favored Sunday and
will maintain that for now...but future shifts may or may not need
to tweak this. Next front penciled in for middle of next week. 47

&&

Preliminary point temps/pops...
College Station (cll) 29 45 34 52 49 / 0 10 20 30 40
Houston (iah) 36 51 36 57 51 / 0 10 10 30 40
Galveston (gls) 40 51 44 56 53 / 0 10 20 30 50

&&

Hgx watches/warnings/advisories...
Texas...small craft should exercise caution until 4 am CST Friday for
the following zones: Galveston.

GM...small craft should exercise caution until 4 am CST Friday for
the following zones: Galveston Bay...Matagorda Bay.

Small Craft Advisory until 4 am CST Friday for the following
zones: waters from Freeport to the Matagorda Ship Channel
out 20 nm...waters from High Island to Freeport out 20 nm.

Small craft should exercise caution from 4 am CST Friday through
late Friday night for the following zones: waters from
Freeport to the Matagorda Ship Channel out 20 nm...waters
from High Island to Freeport out 20 nm.

Small Craft Advisory until 6 am CST Saturday for the following
zones: waters from Freeport to the Matagorda Ship Channel
20 nm to 60 nm...waters from High Island to Freeport 20 to
60 nm.

&&

$$

Discussion...45

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