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Area forecast discussion 
National Weather Service Houston/Galveston Texas
1100 am CDT Friday Jul 3 2015

forecast looks to be on track for this afternoon. Weakening ridge over the
northern Gulf allowing for increasing low-level moisture and perhaps a
more active seabreeze later today. Northern portions of the County warning forecast area could
still get a bump in the precipitation from the activity moving down from North
Texas. 41


Previous discussion... /issued 413 am CDT Friday Jul 3 2015/

At 3 am...a weak surface convergent zone was located from about
kgls to just west of kvct. This feature appears to be the focus
for rain showers/thunderstorms and rain this morning enhanced by some low level speed
convergence. Once mixing develops this morning and the wind field
becomes a bit more broad...feel this activity will wane. There is
also a weak surface trough extending from northern Arkansas to northwest
Texas. This feature will probably stay north of the region but
could sink far enough south by this evening to enhance rain
chances over the extreme northern part of the County Warning Area. Daytime heating
this afternoon coupled with a weak 500 mb trough will allow for
additional rain showers/thunderstorms and rain this afternoon/evening. Have broad brushed 20
probability of precipitation but will likely tweak the probability of precipitation this morning along the coast
and may raise probability of precipitation over the NE zones late this afternoon per
latest trends with the rap/hi-res arw.

The upper level trough will still be in the area on Saturday and
precipitable water values are prognosticated to increase to around 2.00 inches convective
temperatures are between 87-90 degrees with the lower values near the
coast. Daytime heating coupled with the weakness aloft should
allow for some afternoon storms to develop. The weakness aloft
will be competing with building heights to the west and surface
high pressure building in from the east so am expecting coverage
to be somewhat limited. Will maintain chance probability of precipitation for now with the
highest probability of precipitation over the central zones.

Current forecast has 20 probability of precipitation on Sunday but moisture levels begin
to drop and heights begin to build. Was tempted to pull probability of precipitation on
Sunday but prefer to wait and see if the upper level weakness
vacates the region. Upper level ridging builds into the state
Monday and remains over the state through the end of the week.
Temperatures in the superblend look way too cool so leaned toward the
warmer mex/European model (ecmwf) guidance and probably did not go warm enough. A
weak inverted upper level trough will undercut the ridge on
Thursday. This feature could bring some isolated showers but feel
subsidence from the ridge will keep things dry. Heat index values
will likely exceed 100 degrees toward the middle and end of this

Looking ahead...the upper level ridge will likely remain anchored
over Texas. Next weekend looks very warm and continued dry. For
those who were tired of the'll get your wish of drier
weather but you'll also get very warm temperatures to accompany
the drying trend. 43


Preliminary point temps/pops...
College Station (cll) 92 74 91 76 92 / 20 10 20 10 20
Houston (iah) 93 76 90 77 93 / 20 10 40 20 20
Galveston (gls) 90 81 87 81 90 / 20 20 30 20 20


Hgx watches/warnings/advisories...


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