Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Angelo Texas
1140 PM CST Mon Mar 2 2015
LIFR ceilings had returned to nearly all taf sites at 5z. Kabi
was an outlier with MVFR ceilings, but expect it also to fall
below 500 above ground level through 9z. Visibilities should begin improving
after daybreak as southerly winds increase, however, do not
expect most sites to rise to MVFR and until early afternoon. Ksjt
and ksoa will likely rise to MVFR first as drier southwesterly
winds move in. Ceilings should rise to VFR for all sites mid
afternoon, with MVFR stratus returning this evening to the I-10
corridor terminals and kbbd Brady this evening.
Previous discussion... /issued 557 PM CST Mon Mar 2 2015/
LIFR/IFR ceilings will continue tonight into late Tuesday morning,
there should be a gradual improvement in visibilities tonight
however as light easterly upslope winds become south to southeast
and increase to 5 to 15 mph. IFR ceilings otherwise should rise to
MVFR noon Tuesday or a couple hours after.
Previous discussion... /issued 333 PM CST Mon Mar 2 2015/
(tonight and tomorrow)
A big temperature swing remains likely for the next 24 hours. Models
continue to rebound 850 mb temperatures during the next 24 hours.
However, return low-level flow developing tonight does not look as
promising as we were thinking. Thus, surface dewpoints will likely
not rebound as quickly during the next 12 hours, as we were
previously thinking. So, the low for tonight may occur just after
midnight. Also, persistent fog will continue tonight, as will the
potential for light showers across mainly of central and eastern
counties. For tomorrow, we do expect clouds to thin and 850 mb
temperatures to warm. Thus, afternoon highs above seasonal normals,
mainly around 70, look reasonable. Nevertheless, we did lower highs
for tomorrow a few degrees, as compared to previous forecasts. This
cold air, at this surface, has just not yielded as we'd thought it
(tomorrow night through monday)
A return of colder temperatures and wintry precipitation are
possible Wednesday and Thursday...
An Arctic cold front is forecast to move into the Big Country
Wednesday morning then clear the Interstate 10 corridor by early
afternoon. Ahead of this feature, showers and isolated thunderstorms
will be possible Tuesday night into Wednesday morning. Temperatures
will drop quickly as the cold front moves through, with steadily
dropping temperatures through the day. This is indicated in the
current forecast with much of the Big Country at or below freezing
by noon, and much of the rest of west central Texas at or below
freezing by early evening.
An upper level disturbance will approach from the west, resulting in
increasing precipitation chances for all of west central Texas. The
precipitation type forecast continues to be a challenge. Forecast
model soundings indicate rain across most of the area Wednesday
morning, except across the Big Country where freezing rain/sleet
will be possible. As temperatures across the region continue to
drop, a transition to rain or sleet will be possible as far south as
a San Angelo, to Eden, to Brownwood line Wednesday afternoon, with
sleet across the Big Country. Wednesday night into Thursday morning,
a transition to snow/sleet is then expected, as temperatures aloft
cool enough to get rid of any warm layer. Precipitation chances will
end from northwest to southeast Thursday morning.
A lot of uncertainty remains with regard to ice, sleet and snow
accumulations across the region. Accumulating winter precipitation
looks likely, but exactly how much still remains uncertain.
Residents are urged to continue to monitor future forecasts as
hazardous driving/walking conditions will be possible late Wednesday
Another cold day is forecast on Thursday, with forecast highs in the
mid to upper 30s. Given the Arctic nature of this airmass, these
temperatures may eventually need to be trended down. A slow warm up
is then forecast through next weekend.
Preliminary point temps/pops...
Abilene 36 69 39 40 23 / 20 10 40 50 30
San Angelo 37 70 46 47 25 / 20 10 30 50 50
Junction 39 71 51 52 27 / 20 10 30 50 60