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Area Forecast Discussion (AFD)

Issued by Houston/Galveston, TX (HGX)

FXUS64 KHGX 190429

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1029 PM CST Mon Feb 18 2019


After a brief break from the clouds earlier today, stout onshore
flow from the Gulf and isentropic lift associated with that flow, 
has lower clouds spreading across Southeast Texas tonight. Radar 
imagery shows some returns over the Gulf and parts of Chambers
County, but it is unknown how much, if anything, is reaching the
ground with typically drier northeast/east-northeast flow in the
lowest part of the column.

Regardless, things will moisten up through the night, and so as
the sky becomes overcast overnight, rain chances will increase as
well. All in all, the general forecast is going pretty well, but
have tweaked most all of the elements to fit a little better with
obs. Perhaps the biggest impact is to delay the onset of the best
shower potential to tomorrow, rather than really cranking things
up tonight. Though lightning hasn't really gotten started yet,
will continue to allow for an isolated to widely scattered
elevated thunderstorm tomorrow as a warm front pushes up ahead of
a developing coastal low.

Also, I've chosen to add a small area of fog in the developing
low's warm sector. This should mostly be an impact to the Gulf
waters, but some patchy fog may push into the easternmost portions
of our area depending on the precise track of the low. NBM's vis
grids seemed to track pretty well, so that made the bulk of the
forecast. However, a consensus of short range models does indicate
more of the area could see some fog if the low tracks inland a
little earlier/farther west.


.PREV DISCUSSION /Issued 553 PM CST Mon Feb 18 2019/...

Still looking at gradually deteriorate conditions beginning this evening
and continuing overnight and Tuesday with lowering ceilings and rising
rain chances. MVFR ceilings expected to develop from south-to-north
tonight. Chances of rain increase tomorrow, and expect all sites to
transition to IFR ceilings and visibilities with expanding areas of
mainly -RA/RA developing in the morning and persisting throughout the
day. A few isolated TSRA are possible, but continue to leave mention
out of the TAFs as overall chances of an individual site being impacted
look fairly low. Looking at mainly NE/ENE winds at 10 to 15 knots 
(occasionally gusty, especially closer to the coast).  42



College Station (CLL)  44  46  43  61  44 /  40 100  30  10  20 
Houston (IAH)          47  56  49  62  50 /  50 100  50  20  50 
Galveston (GLS)        53  65  54  61  56 /  60 100  50  40  50 



GM...Small Craft Advisory until 9 AM CST Tuesday for the following 
     zones: Galveston Bay...Matagorda Bay.

     Small Craft Advisory until noon CST Tuesday for the following 
     zones: Coastal waters from Freeport to Matagorda Ship 
     Channel TX out 20 NM...Coastal waters from High Island to 
     Freeport TX out 20 NM...Waters from Freeport to Matagorda 
     Ship Channel TX from 20 to 60 NM...Waters from High Island 
     to Freeport TX from 20 to 60 NM.