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Area forecast discussion 
National Weather Service Houston/Galveston Texas
1151 am CST Tuesday Dec 1 2015

see the 18z aviation discussion below.



given that there was a hodgepodge of conditions across southeast Texas
at 17z...confidence in the forecast models and guidance is
challenging. A narrow area of VFR conditions stretched from kcll
to Crockett. Am expecting VFR to develop over kcll...kuts...and
kcxo early this afternoon. Elsewhere conditions range from IFR to
MVFR. Tried to time the VFR breakout to the satellite trends and
the NAM forecast sounding/time section plots. Expect that from
kiah to the coast a brief period of VFR is possible during the middle
and late afternoon. Expect MVFR to redevelop this evening with a
chance of showers from about 05z to 10z as a reinforcing cold
airmass works its way to the coast. VFR conditions will likely
develop area-wide after 10 to 12z.



Previous discussion... /issued 1006 am CST Tuesday Dec 1 2015/

made a few small changes to grids. Radar showing a few bands of
weak returns corresponding to some light rain or drizzle.
Satellite showing some thinning of the overcast over far northern
counties...otherwise cloudy everywhere. This afternoon expect more
patches of light rain or drizzle mainly southern half of forecast
area. Some veiled sunshine possible northern counties as slightly
drier air filters in from the north. Should remain cool with highs
mainly in the middle to upper 50s...perhaps around 60 far north if
they get that veiled sun. Should clear out from north to south
tonight behind secondary cold front. Plenty of sun on tap for
tomorrow. 46

Previous discussion... /issued 440 am CST Tuesday Dec 1 2015/

embedded impulses riding along the area's deep west-southwest flow aloft
will help to continue to bring periods of rain across parts of southeast
Texas today and tonight. The central U.S. Middle/upper level low's eastward
movement will help to finally break our cloudy and damp weather pattern
late tonight up north and during the day on Wednesday from north to
south as drier air filters into the area. Clear skies associated with
this pattern change will bring our area some colder morning lows beginning
on Thursday morning. With surface high pressure then building into the
area from the north through the end of the week...some near freezing
temperatures might be possible by Friday morning at a few of our far
northern locations (this forecast package will generally call for middle
to upper 30s inland and around the middle 40s along the coast). Latest
model runs have been trending low temperatures downward...and we might
need to lower both friday's and saturday's numbers on forecast updates
over the next couple of days. Will continue to indicate gradually increasing
clouds over the weekend and bring low rain chances back into the forecast
beginning on Sunday as the next storm system begins its eastward track
across the Southern Plains. 42


Stationary front lingering just outside the marine waters to the
southeast. Short wave moving through aloft has helped to increase coverage
of -ra/rain showers over the coastal waters this morning. As upper speed maximum
departs the region may get one more burst of precipitation late this
afternoon through early morning then the 850 front moves into the
coastal waters and Ushers in stronger northerly winds. Winds
Wednesday will likely warrant Small Craft Advisory conditions for winds nearshore and
offshore and seas of 5 to 7 feet well offshore. These stronger
winds persist into Thursday then gradually relax through Thursday
afternoon. Easterly flow Saturday in response to next upper trough
moving into the state...with another cold front on Monday.

Tides around 1 foot above normal but should remain below criteria
for coastal flooding during high tide this evening. Tides falling
back to near normal Wednesday in the wake of the cold front.


Aviation... mix of IFR 600-900 and MVFR 1000-2500ft ceilings across the
region. A band of IFR from SW to NE through the Houston metropolitan area
and northward and patchy MVFR ceilings south of this band. This band
should slowly shift southward this morning as flow aloft veers and
expect this band of lower ceilings to also slowly lift. Iah/hou MVFR
ceilings should prevail 15-18z and beyond until 22-01z with dry air
bringing VFR conditions. Northerly winds 8-12kts are on tap


Preliminary point temps/pops...
College Station (cll) 59 45 61 39 60 / 20 20 10 0 0
Houston (iah) 58 48 60 41 60 / 40 40 10 0 0
Galveston (gls) 60 54 61 48 60 / 40 50 30 0 0


Hgx watches/warnings/advisories...
GM...small craft should exercise caution until 3 PM CST this
afternoon 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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