Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
FXUS64 KEWX 241146
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
646 AM CDT TUE MAY 24 2016
Low CIGs will continue through the morning. Think LIFR is unlikely
at this point. CIGs should get to VFR by the middle of the
afternoon. The pattern should repeat overnight tonight.
.PREV DISCUSSION... /ISSUED 326 AM CDT TUE MAY 24 2016/
SHORT TERM (Today through Wednesday)...
Mostly cloudy skies are prevailing across the region with ample
low-level moisture in place. There have been a couple of
observation sites reporting brief light rain and will include the
mention of sprinkles in the morning hours. For this afternoon,
things should be a bit quieter across the region. High-res
guidance shows some showers across the eastern zones once again
and will show the higher pops (20s) in this area. The dryline will
be just west of the region this afternoon and can`t rule out an
isolated thunderstorm moving into the western CWA late this
afternoon or evening. There will be a conditional threat of severe
weather as the atmosphere would support severe convection. Will
mention thunderstorms in the official forecast with only a 10 pop
as the threat is low.
On Wednesday, an upper trough will be moving east and will be
centered near southern California. Ahead of this feature, models
are progging a shortwave trough embedded in southwest flow aloft
to move into the region. This feature will help aide in the
development of shower and thunderstorm activity in the late
afternoon and evening hours out west along the dryline. There
will be a CAP in place initially but both the GFS and ECMWF are
progging decent amounts of QPF across the western CWA which
indicates the CAP is likely to break as convective temps are met.
CAPE values in the late afternoon evenings will be near 3500 J/Kg
and there will be a threat of severe storms with any activity that
develops across the northwestern CWA. Large hail would be the main
threat with steep mid-level lapse rates in place.
LONG TERM (Wednesday Night through Monday)...
For Wednesday night, there should be some sort of convective
complex ongoing assuming storms do develop in the late afternoon
hours. Severe chances would likely diminish in the overnight
period with the loss of day time heating.
Thursday and Thursday night, the previously mentioned upper
trough will be approaching West Texas and the Panhandle. As this
feature moves closer, large scale forcing for ascent will be on
the increase. The best lift will be north of the CWA and the bulk
of the storm activity should be north of the region as well.
However, there remains decent chances for thunderstorms in the
CWA especially in the evening hours. There is an enhanced risk of
severe storms just north of the region with a slight risk along
and west of the I-35 corridor. 850 winds will be from the south
around 35 knots in the afternoon with 0-3km helicity values near
250 m2/s2. In addition to a large hail risk there would also be a
possible isolated tornado risk as well.
The base of the upper trough will move into the southern plains
on Friday and as this occurs, the dryline should be able to push
farther east in the afternoon hours. This should ensure that the
bulk of the shower and storm activity will be east of I-35 mainly
east of the dryline. The dryline will retreat back to the west by
Saturday morning and the better convection chances Saturday
afternoon will be across the western half of the area. Once again,
CAPE and shear values will support the threat of severe convection
with any cells that are able to be be sustained in the boundary
On Sunday, another shortwave trough will move north of the region
and the bulk of the activity will remain north of the CWA. Can`t
rule out an isolated shower or storm and will keep a 20 PoP in the
forecast. The same can be said for Monday as most of the storms
will remain near the dryline which is expected to be west of the
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 88 75 89 73 85 / 20 10 20 20 60
Austin Bergstrom Intl Airport 88 75 90 74 85 / 20 10 20 20 60
New Braunfels Muni Airport 89 74 89 73 86 / 20 10 20 30 60
Burnet Muni Airport 86 73 87 71 85 / 10 10 10 20 60
Del Rio Intl Airport 92 76 93 74 90 / 10 10 20 50 30
Georgetown Muni Airport 86 74 88 73 84 / 20 10 10 20 60
Hondo Muni Airport 89 75 91 74 89 / 10 10 10 40 60
San Marcos Muni Airport 88 75 89 73 84 / 20 10 20 30 60
La Grange - Fayette Regional 88 76 88 75 85 / 20 10 20 10 50
San Antonio Intl Airport 89 75 90 74 86 / 10 10 20 30 60
Stinson Muni Airport 89 76 91 74 88 / 10 10 20 40 60