Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Houston/Galveston Texas
1212 PM CST sun Mar 1 2015
rather messy forecast expected to continue this afternoon/tonight/likely
into Monday morning. Generally vlifr/LIFR conditions prevailing as
fog affects southeast Texas. Overrunning moisture atop the warm front and
disturbances moving in from the west adding to the overall pic-
ture. Prognosticated soundings and MOS guidance keeping most/all sites
socked in through the overnight hours. Perhaps some improvement
Monday middle-morning for inland tafs...but coastal tafs could remain
messy these next few days. 41
Previous discussion... /issued 1007 am CST sun Mar 1 2015/
morning forecast update.
latest surface analysis has a coastal low off Matagorda Bay along the
Upper Texas coast. There appears to be two boundaries of concern. The
first has pushed more inland and separates airmass with temperatures in
the 40s from airmass with temperatures in upper 50s to low 60s. Second
boundary is the true warm front which separates the upper 50s/low
60s from the upper 60s/low 70s with dewpoint temperatures in the upper
60s as well. The 12z crp and lch soundings capture the cooler
boundary layer airmasses north of these boundaries. One glaring
difference is the crp sounding shows an elevated mixed layer and
cap at 700mb where lch does not. This means lifting an elevated
parcel would result in convection and reason why there has been
some isolated thunderstorms and rain between Houston and Beaumont. Suspect the eml will
advect over southeast Texas more in the coming days and likely be a factor
in the forecast when the strong cold front comes Wednesday. Until then
main concerns will be how/when/where warm front pushes
north/stalls and then pushes north again through Tuesday. Temperature
forecast will be very challenging. Only changes to the forecast
this morning were for temperature trends and rain chances.
Early look at 12z model runs...NAM is significantly slower with
frontal passage on Wednesday. GFS has become much more wet behind the front on Wednesday
into Thursday. Wednesday night forecast will be an interesting one.
Preliminary point temps/pops...
College Station (cll) 49 44 56 52 74 / 50 40 40 30 40
Houston (iah) 60 53 62 58 75 / 60 30 40 30 30
Galveston (gls) 64 54 67 63 71 / 60 30 30 20 20
Texas...dense fog advisory until 10 PM CST this evening for the
following zones: Brazoria...Chambers...Galveston...
GM...dense fog advisory until 10 PM CST this evening for the
following zones: Galveston Bay...Matagorda Bay...waters
from Freeport to the Matagorda Ship Channel out 20 nm...
waters from High Island to Freeport out 20 nm.
Small craft should exercise caution until noon CST today for the
following zones: waters from Freeport to the Matagorda Ship
Channel 20 nm to 60 nm...waters from High Island to
Freeport 20 to 60 nm.