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Area forecast discussion 
National Weather Service San Angelo Texas
640 PM CDT Tuesday Jul 29 2014

showers and thunderstorm activity will continue for the next several
hours over the Big Country and the northern Concho Valley.


have increased pops over the Big Country and northern Concho Valley
with lingering on-going activity. Have also updated other parameters
given substantial associated cooling. Showers and thunderstorms
should diminish quickly with loss of daytime heating.


Previous discussion... /issued 352 PM CDT Tuesday Jul 29 2014/

Short term...
(tonight and wednesday)

At 3 PM, afternoon clouds are a little more widespread today,
helping cool temperatures a few degrees, with isolated showers and
thunderstorms developing. Mesoanalysis and point soundings across
the area show cloud bases are slightly lower, due to the cooling
temperatures helping to decrease the temperature/dewpoint
depression. However, with cloud bases around/above 7000 feet, and
the aforementioned depression greater than 35 degrees fahrenheit
in most areas, microbursts remain possible. Mesoanalysis show
around 1500 j/kg MLCAPE available for the thunderstorms to work
with, so a few strong/marginally severe storms can't be ruled out.
The main storm hazards will be deadly cloud to ground lightning,
and wind gusts over 40 mph with the stronger thunderstorms that
develop. These showers/thunderstorms will quickly diminish after
sunset, with the loss of heating. Lows tonight will be mainly
lower 70s.

For tomorrow, models develop isolated showers and thunderstorms
across northern parts of the area, mainly north of the Colorado
River. We believe this potential may be a little less in coverage
compared to today/yesterday. Model analysis again shows high cloud
bases, leading to a microburst potential with any storms that
develop. Highs tomorrow will be mainly in the upper 90s, with a few
locations touching 100 degrees.

Long term...
(wednesday night through next tuesday)

A cold front will move across the area Wednesday night into
early Thursday, bringing cooler temperatures areawide through
next weekend, along with a chance of rainfall into Saturday.

Models agree that the synoptic cold front will enter the northern
Big Country counties late Wednesday evening and will move slowly
south across the area on Thursday. The front will bring cooler
temperatures to the entire area Thursday through next weekend,
with below normal high temperatures through the period. As for
rain chances, the 18z GFS has come in considerably wetter and is
currently the outlier compared to the NAM and European model (ecmwf). The GFS
stalls the front across southern sections Thursday night through
Saturday and generates a considerable amount of quantitative precipitation forecast along and
north of the front through the period. The ec and NAM drive the
front south of the area by Thursday evening, with precipitation
confined to southern sections by Friday evening and dry
conditions for Saturday. Believe that the GFS is too far north
with the front and have discounted its wetter solution. Thus, will
maintain a 20 to 30 percent chance for showers and thunderstorms
across the area Wednesday night and Thursday as the front moves
through, with a slight chance for precipitation across far
southern sections Thursday night through Saturday.

Temperatures will be considerably cooler behind the front on
Thursday, especially across northern counties. Highs will range
from the lower to middle 80s across the Big Country, to the upper
80s and lower 90s elsewhere. Below normal temperatures continue
Friday through next Monday with afternoon highs mainly in the
lower 90s. Lows through the period will be in the upper 60s and
lower 70s.


Preliminary point temps/pops...
Abilene 73 97 70 85 67 / 10 20 20 20 10
San Angelo 73 99 72 91 69 / 10 10 10 20 20
Junction 71 98 72 92 71 / 10 0 10 30 20


Sjt watches/warnings/advisories...



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