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Area forecast discussion 
National Weather Service San Angelo Texas
349 am CDT Wednesday Jul 30 2014

Short term...
(today and tonight)

The NAM and GFS models generate isolated showers and
thunderstorms mainly north of I-20 this afternoon, ahead of a cold
front that will be moving into the Red River valley late
afternoon, over all, storm coverage is indicated to be more sparse
than Tuesday. Instability is also less, with NAM and GFS sb convective available potential energy
at 7 PM CDT less than 200 j/kg. Frontal passage is indicated to be
slower than yesterdays models, with the front along an Sweetwater
to Haskell line around 1 am tonight, and from San Angelo to
Abilene around 7 am Thursday. Depending on the amount of
convection, however, the cold front may be pushed slightly faster
and farther south.

Southerly winds will be stronger and more gusty today, as a
surface low develops in the Permian Basin this afternoon. Highs
will be 2-4 degrees warmer in the mid 90s in the Big Country
today, with more isolated storm coverage. Highs in the upper 90s
to 100 degrees expected farther south, despite upper level
cloudiness.

04

Long term...
(thursday through next tuesday)

The much-advertised cold front is still expected to move into and
through most of the area during the day Thursday. As the front
moves through the area, precipitation chances will shift generally
from the northern third of the County Warning Area to the southern third.

Models have generally good agreement of the initial push of the
front with the 29/00z runs, pushing it into our I-10 corridor by
Thursday evening. Thereafter, the front becomes diffuse, and hard
to discern in model data. Have kept the general theme from the
previous forecast with regard to precipitation chances. Will keep
20-30 percent chances across most of the area Thursday, and a
general migration of rain chances southward into our I-10
corridor by Friday night.

The GFS/European model (ecmwf) keep a moisture plume near our southern counties,
and generally northwest up the Pecos River valley through Saturday
night, with the ec being slightly drier. This, along with
persistent easterly upslope flow across the area argues for
keeping at least a slight chance of showers and thunderstorms
through Saturday for our I-10 corridor counties into the southern
Concho Valley. Have kept a slight chance only in Crockett County
for Sunday/Sunday night for now, but this may need to be expanded
back to the east as well in future updates to the forecast.

Temperatures behind the front will be cooler with highs initially
in the 80s across the Big Country, lower 90s south for Thursday
and Friday, with temperatures generally in the lower 90s for the
entire area from Saturday into early next week. Lows will remain
near normal, generally from the upper 60s to lower 70s.

20

&&

Preliminary point temps/pops...
Abilene 96 70 85 66 88 / 20 20 20 10 10
San Angelo 99 72 91 68 90 / 10 10 20 20 20
Junction 98 72 92 72 91 / 0 10 30 20 20

&&

Sjt watches/warnings/advisories...
none.
&&

$$

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