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Area forecast discussion 
National Weather Service Houston/Galveston Texas
1018 am CST Sat Jan 31 2015

Update...
upper level ridge...yesterday over northern Mexico has moved off
to the east...and an upper level trough over southern Nevada is
sending impulses out ahead of the trough into Texas producing
cloud cover for southeast Texas...and rain for areas along and
west of Interstate 35. Short range models hinting at precipitation
beginning late this afternoon into the evening hours. Visible
satellite showing extensive cloud cover across Texas that will
limit high temperatures for today. Only edit made was to dewpoint
grids to match the observation. 13

&&

Previous discussion... /issued 415 am CST Sat Jan 31 2015/

Discussion...
rain chances will increase later today and tonight with gradually
increasing moisture levels and a transition to a SW flow aloft
(and associated embedded impulses). Models in fairly good agreement
showing a band of light precipitation approaching areas west of a College
Station-Edna line late in the afternoon and early evening. Though isolated
popcorn rain showers will be possible generally after 2 PM further east...the
vast majority of the area should mainly be dry during the day.

Broken band of rain showers should push eastward across the remainder of southeast Texas
during the evening hours bringing just nuisance rainfall amounts.
Past few Texas tech WRF runs have been showing a break in the weather
until the cold front itself moves into southeast Texas early Sunday afternoon.
Lowered probability of precipitation some from midnight-noon for most areas but have a
feeling they could still potentially be overdone during that time
period. We do expect scattered (re)development along the front as it
moves into the cll area early in the afternoon and eventually fill into
a line of rain showers and embedded thunderstorms and rain as it approaches the metropolitan area
around 3 PM & off the coast early in the evening. The passing cold
front will bring an end to the precipitation Sunday evening west/ dry cool
weather expected Monday.

Latest models guesses kickout the cutoff Baja California low late Monday and
take it on a more northern track than earlier runs. Developing
surface coastal low will thereby also taking a more northern track &
closer to the Upper Texas coastline. Result would be an expansion of
rain further inland Tuesday/Wednesday rather than just closer to the coast
and offshore. Bumped probability of precipitation up a touch during that time period but
they will obviously need to be adjusted once confidence of
timing/track of upper low becomes better established. May need to
keep an eye on potential for locally heavy rains near the coast as
dynamics setting up similar to last Thursday. Again - way too far out
& things will likely change - but Worth keeping an eye on.

Once the upper trough departs to the East...Ridge out west will
amplify putting US in a dry northwest flow aloft during the 2nd half of
the week. 47

Marine...
moderate east winds to persist as high pressure lingers over the eastern
U.S. Today. But we should see the return of onshore winds across our
coastal waters tonight/Sat as the next storm system begins to deepen
over the Central Plains. This system (along with a cold front) forecast-
Ged to sweep into our coastal waters Sun night...but may be preceded
by a coastal low developing/moving up from the Lower Texas coast during
the day on sun. These features should make for unsettled weather/slightly
elevated winds and seas starting late Sat on into sun. Caution flags
may be needed during this time frame.

These caution flags will likely be upgraded to small craft advisori-
es with the passage of the very strong cold front Sun night. However
not going with a gale watch at this time as models generally keeping
sustained winds under criteria...but not ruling out wind gusts at/or
near gale force for Monday. Winds/seas to decrease Tuesday as high pressure
builds into the region. Then a brief period of light/moderate east/southeasterly
winds through middle week with the next front prognosticated for Thursday. 41

Aviation...
patchy MVFR ceilings expected this morning as low-level moisture contin-
ues to increase across southeast Texas. Short-range models hinting at possible
light precipitation starting this afternoon as disturbances move across from the west
and SW...but will likely opt to keep any mention out (save for vcsh)
until later. 41

&&

Preliminary point temps/pops...
College Station (cll) 62 58 65 37 49 / 40 60 60 10 0
Houston (iah) 62 58 69 41 51 / 20 50 70 20 0
Galveston (gls) 62 57 64 45 50 / 20 40 50 30 0

&&

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

$$

Discussion...13

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