Area Forecast Discussion
Issued by NWS San Angelo, TX
FXUS64 KSJT 102307 AAA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
507 PM CST TUE DEC 10 2013
See aviation discussion below...
Light and variable winds are forecast overnight with VFR conditions
prevailing. A cold front will move through West Central Texas
Wednesday morning, resulting in a wind shift to the north at 5 to 10
knots. Stratus development is possible behind the front during the
late afternoon/evening hours Wednesday. For now, I went ahead and
included MVFR ceilings at KABI around 22z, and may need to expand to
the other sites in the next TAF package.
.PREV DISCUSSION... /ISSUED 330 PM CST TUE DEC 10 2013/
/Tonight and Wednesday/
An upper level shortwave trough will move across the Central
and Northern Plains this evening and across the Great Lakes on
Wednesday. This system will send another cold front south across
the area Wednesday morning and will bring a cooler airmass into
West Central Texas once again. For tonight, mainly clear skies
expected across northern sections with partly cloudy skies across
southern sections as some high clouds move into the area from the
southwest. Lows tonight will range from the lower 20s north to the
mid and upper 20s elsewhere.
The cold front will enter the Big Country shortly after sunrise
Wednesday and clear the I-10 corridor by early afternoon. Went
with the cooler MET guidance for highs on Wednesday given decent
cold air advection during the day. Highs will range from the upper
30s across the Big Country, to the mid and upper 40s along the I-10
/Wednesday night into Tuesday/
Good radiational cooling conditions are again expected Wednesday
night as surface high pressure with dry air builds over the region.
GFS and NAM guidance indicate upper teens and lower 20s for lows
across West Central Texas, which look good.
Upper low off the coast of Baja California is still expected to open
up as it heads east across Texas Friday. May see a few light showers
ahead of the system Thursday night and early Friday, however models
are indicating an increasingly dry forecast. While the EC model
still indicates scattered light showers Thursday night, the NAM and
GFS model algorithms are nearly precipitation free as the mid levels
indicated little moistening with dry southwest winds aloft. For now,
I am keeping a slight chance of rain Thursday night, but confidence
is decreasing on the potential for measurable rainfall.
Very dry air through the atmospheric column ahead of a cold front
Saturday will preclude precipitation chances. Front is not as strong
as previous front, however there should still be an 8 to 10 degree
drop from Friday. Warming with a large diurnal temperature change
are expected Sunday to Tuesday.
.PRELIMINARY POINT TEMPS/POPS...
Abilene 25 38 17 41 32 / 0 0 0 5 20
San Angelo 27 43 21 51 31 / 0 0 0 5 20
Junction 26 48 23 52 30 / 0 0 0 5 20