Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Houston/Galveston Texas
1002 am CDT Friday Jul 25 2014

pre-sunrise showers that developed on the land breeze over
Chambers County and points offshore are beginning to wane and are
forecast to die out through the 10 am hour. Upper ridging will be
the main player today in inhibiting much in the way of afternoon
showers and isolated storms. There is still a slight chance for
the development of pop-up showers/storms most likely focused
along outflow boundaries from yesterday's activity or along the
evolving sea breeze boundary. Coastal cloud cover will likely
influence the delayed onset of the breeze but...with lower 90f
convective temperatures...widely scattered convection is not out
of the question. Eastern Texas still falls on the relatively
weaker southeasterly periphery of northwestern Texas-centered
upper ridging. Thus...a quick shower passage or the rumble of
thunder will exist for the southern half of the forecast area. 31


Previous discussion... /issued 611 am CDT Friday Jul 25 2014/

see aviation for 12z taf discussion.

early morning convection that developed near Beaumont has spread
westward this morning and is nearing Galveston. This activity
should diminish by middle morning and VFR conditions are expected
through the taf period for most sites. Bay/sea breeze likely to
push inland to iah by late afternoon bringing a period of
southeasterly winds. 38


Previous discussion... /issued 420 am CDT Friday Jul 25 2014/

area radar are a little more quiet than 24 hours ago. Still a few
showers off the la/Texas coast. Surface analysis shows some deeper
moisture along the coast but not showing any boundary for low
level convergence. Mainly calm winds and clear skies have allowed
for some patchy fog and temperatures dropping into the middle 70s for most
of southeast Texas. Upper air analysis shows 500mb ridge centered over north.M.
Into Texas Panhandle and SW Kansas. A broad trough remains over much of
the eastern U.S. With a shear axis training back along the north Gulf
Coast. This feature is weakening as the ridge begins to expand
this weekend.

Today looks to be similar to the last couple of days with mainly
afternoon thunderstorms that develop along any old outflow boundaries
and sea breeze. Looking at water vapor not see any
weak shortwave troughs rotating around the ridge that may support
thunderstorm activity today. Also NAM/GFS bufr soundings look a
little more stable with NAM showing a bit of a cap developing.
Think 20 probability of precipitation looks about right as there is still 1.8 to 2 inches
of precipitation water based on 00z lch/crp soundings. Any storms that do
form should be capable of brief heavy rainfall...gusty winds and

Synoptic models are in pretty good agreement with expanding upper
level ridge northwest from Texas into The Rockies. Look for the ridge to be
strong enough to inhibit convection due to subsidence. Also look
for maximum temperatures to be a couple degrees warmer than last few days but
seems like there has been enough soil moisture to keep maximum temperatures
from increasing too much. For the most part kept temperatures over the
weekend into next week close to guidance numbers which seem to be
doing quite well.

Sun night into Monday strong shortwave moves through the Midwest
into the mid-Atlantic. This keeps broad trough in place and
supports a cold front pushing towards southeast Texas by Tuesday. Cold front
slowly back doors into the area Tuesday/Wednesday with it being focus for
convection. Front for the most part stalls northwest/southeast across the area
by Wednesday with scattered thunderstorm activity. Added 30 probability of precipitation to the
forecast Tuesday night through Thursday as there is the potential for a
heavy rainfall event mover North Texas into East Texas. The European model (ecmwf) forecast is
more robust with precipitation for the end of next week with a more
potent shortwave rotating through North Texas into west la on Thursday. Overall
upper level pattern holds onto northwest flow aloft so think the pattern
sets up nicely for heavy rainfall. For good measure the GFS sets
up a band of 2-2.2 inch precipitation water along the boundary which
would support heavy rainfall as well. Temperatures were also
decreased a bit for the end of the week with convection expected
and the front pushing into the area. Temperatures could be very easily be
2-4 degrees below normal ahead of the first week of August which
is notorious for 100 degree days. 39


light to moderate south southwesterly flow will continue through
the weekend. Winds will ease slightly early next week as a cold
front moves into southeast Texas. 38


Preliminary point temps/pops...
College Station (cll) 96 76 97 77 97 / 10 10 10 10 10
Houston (iah) 95 76 96 77 95 / 20 10 20 10 10
Galveston (gls) 91 80 92 81 92 / 20 10 10 10 10


Hgx watches/warnings/advisories...



National Weather Service Glossary of Abbreviations