Area Forecast Discussion
Issued by NWS San Angelo, TX
FXUS64 KSJT 301817
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1216 PM CST Fri Jan 30 2015
CIGS will degrade to MVFR overnight and into IFR towards morning
across West Central Texas. Rain will be developing from West to
East, mainly after midnight. A Few patches of rain possible this
evening, however. Rain could become moderate at times, especially
at KABI and KSJT after 9Z.
.PREV DISCUSSION... /ISSUED 511 AM CST Fri Jan 30 2015/
VFR conditions will continue at all terminals through the day and
into the evening hours before degrading to MVFR be late evening
at all terminals and through the overnight hours. An upper level
system moving into the area will bring a chance of rainfall to all
terminals after midnight accompanied by occasional IFR ceilings.
PREV DISCUSSION... /ISSUED 300 AM CST FRI JAN 30 2015/
(Today and Tonight)
An upper trough will dominate the western CONUS today with a closed
upper low over southern California. A southwest flow aloft on the
eastern periphery of the western trough will pump substantial Pacific
moisture over the Desert Southwest today including extreme West
Texas. There is a slight chance of light rain encroaching into at
least the western section of Crockett country later this morning
with chances of light rain reaching the western tier of our CWA
counties by later this afternoon. As the upper trough continues to
trek eastward through tonight, concomitant with periodic
disturbances embedded in the southwest flow aloft, chances of rain
will be on the increase and should envelop the entire forecast
area by late this evening and through the overnight hours. The
best chance of meaningful rainfall will be tonight over the
western two thirds of the forecast area. Highs today under cloudy
skies will be in the upper 40s to the lower 50s. Looking for
morning lows tomorrow in the upper 30s over the Big Country and
lower 40s elsewhere over the area.
(Saturday through Thursday)
The main concern in the extended forecast is the chance for rain
this weekend. An upper level low will be located over southern
California on Saturday, then slowly drift south toward the southern
Baja California peninsula by early next week. In the meantime, West
Central Texas will be in southwest flow aloft, with intermittent
disturbances resulting in areas of light to moderate rainfall. At
this time the best chance of rain looks to begin across our western
counties Friday night/Saturday morning, spreading into much of West
Central Texas during the day Saturday, with the best rain chances
shifting east late Saturday/early Sunday. At this time, rainfall
totals through the weekend of one quarter to three quarters of an
inch look to be common, with some areas seeing over an inch of
rainfall. The expected rain/cloud cover will keep highs on Saturday
from getting much higher than the upper 40s to lower 50s at most
locations, with overnight lows in the upper 30s to mid 40s.
A cold front will move through the area on Sunday, resulting in a
reinforcing shot of cooler air and north winds of 10 to 15 mph.
Showers will once again be possible, with the best chance across the
southern half of the area. Skies will clear from north to south late
Sunday, with fairly good radiational cooling conditions setting up
for Monday morning. This will result in cold morning temperatures,
with lows ranging from the mid 20s across much of the Big Country,
to near 30 across the Interstate 10 corridor.
The aforementioned upper level low will eventually moves northeast
across Mexico, then across South Texas late Tuesday into Wednesday.
At this time, any precipitation associated with this feature is
forecast to remain south of West Central Texas, so a dry forecast
was continued for the middle of next week. Highs for the first part
of the week will be near seasonal normals, in the 50s to lower 60s
and overnight lows in the 30s to lower 40s. Another cold front is
forecast to move through the area Thursday morning, reinforcing the
below normal temperatures.
.PRELIMINARY POINT TEMPS/POPS...
Abilene 40 49 41 49 27 / 50 100 60 30 10
San Angelo 40 53 44 53 29 / 70 90 50 30 10
Junction 43 56 48 56 31 / 50 80 60 50 20