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Area forecast discussion 
National Weather Service Houston/Galveston Texas
628 am CDT Monday Sep 1 2014

see aviation for 12z taf discussion.


IFR ceilings have overspread the northern taf sites this morning but
should begin to improve quickly after sunrise. Light rain showers offshore
approaching gls and should gradually spread inland through the
morning hours. Less moisture to work with today but could still
see some isolated activity inland. Instability high enough to go
with thunderstorms in the vicinity through the early afternoon for metropolitan area taf sites.
Another round of MVFR/IFR ceilings possible again early Tuesday. 38


Previous discussion... /issued 432 am CDT Monday Sep 1 2014/

low pressure in the plains should deepen today and support
stronger southeast winds at the surface. Tropical moisture has decreased some
across the area but precipitation water values still remain around 1.9-2
inches per soundings and GOES sounder data. Upper level trough
over the plains will pull towards the Great Lakes with a trailing
shortwave moving across the c plains by this afternoon. Upper
level ridge is in the process of becoming more established over
the area as heights should rise today. Upper level ridge should
remain broad and flat across the southern U.S. Into Tue/Wed.

Infrared satellite imagery over the Caribbean shows a tropical wave
moving over the Yucatan this morning. This wave should emerge into
the Bay of Campeche tonight into Tuesday. The GFS/European model (ecmwf) agree with
keeping the tropical wave an open wave moving towards the Mexican
coast. The NAM and Canadian close off a circulation with the
possibility of a tropical storm forming before landfall Tuesday night
into Wednesday. Canadian is most aggressive. NHC gives the system a 60
percent chance of tropical cyclone development the next 48hrs and
70 percent chance over next 5 days. The environment is at least
looking more favorable for development. Latest forecasts have all
been very consistent with bringing the system regardless of
strength into the Mexico coast. Greatest impact from this system
on the Texas coast will be increasing seas and tropical moisture.
While the upper level ridge will be in place...there still should
be plenty of moisture for thunderstorm chances Tuesday/Wednesday so will
keep 30/40 probability of precipitation in the forecast with 50 probability of precipitation on Tuesday. Locally heavy
rainfall will again be possible with intense rain rates in
stronger storms.

The rest of the week will be a battle between subsidence from the
upper level ridge and convection developing due to day time
heating with the tropical moisture. Forecast will at least keep 20
probability of precipitation for the of the week into the coming weekend. Upper level
ridge will remain stretched over Texas with weakly amplified almost
zonal jet stream flow across the northern half of the U.S. Main
differences in the GFS/European model (ecmwf) for the extended forecast is a back
door front coming into the area per the European model (ecmwf). This will still be
difficult to do since the pattern is still weakly amplified and
the ridge may be strong enough to keep the front out of the area.

isolated showers will continue across the coastal waters today.
Expect onshore winds to persist through much of the week with
speeds increasing beginning late tonight as pressures begin to
lower across the Bay of Campeche. May need caution flags as early
as tonight but likely beginning on Tuesday. Approaching swells
will bring wave heights up by another foot or two across the
offshore waters by Wednesday. 38


Preliminary point temps/pops...
College Station (cll) 95 77 94 76 94 / 20 10 30 20 20
Houston (iah) 93 77 91 76 92 / 20 20 50 20 30
Galveston (gls) 90 81 88 81 89 / 20 30 40 20 30


Hgx watches/warnings/advisories...



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