425
FXUS64 KEWX 280515
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1215 AM CDT Sun Apr 28 2024

...New AVIATION...

.UPDATE...
Issued at 1139 PM CDT Sat Apr 27 2024

Based on the current trends of storms ongoing across the Edwards
Plateau and the downstream environment that`s in place, we have
collaborated with SPC and WFO SJT to expand the Severe Thunderstorm
Watch a row of counties eastward. The timing of the watch and the
associated hazards remains unchanged from the initial issuance. The
need for any additional watches or extensions overnight remains
uncertain as many of the CAMs show a weakening trend towards sunrise
as the line of storms approaches the eastern Hill Country and I-35
corridor.

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 243 PM CDT Sat Apr 27 2024

Key Points

* Isolated to scattered strong to severe storms overnight into early
  Sunday, mainly along and west of Interstate 35.
* All hazards possible, including large (possibly very large,
  greater than 2 inch) hail, damaging winds, and a tornado or two.

The latest radar data shows some weak showers ongoing from the
southern Edwards Plateau eastward into the Hill Country and nearby I-
35 corridor. With some breaks in the clouds and continued heating,
we could see a few storms develop this afternoon. However, chances
are fairly low (20-30%). Gusty southeast winds continue this
afternoon with wind speeds expected to stay just below Wind Advisory
criteria (sustained 26 mph).

Most of the evening hours should see convection remaining largely to
our north. However, this will change as we head into the overnight
hours as a Pacific cold front and upper level trough axis approach
from the west. We should see a line of convection develop along and
ahead of the front as the boundary encounters plenty of low-level
moisture. While the stronger forcing for ascent remains north of our
region, we could still see some strong to severe storms develop
early Sunday morning. Timing may have trended just a little slower,
but not by much and the inherited forecast had this covered.
Forecast soundings still show favorable CAPE and wind shear, with
all modes of severe weather possible. This includes large (possibly
very large, greater than 2 inches in diameter) hail, damaging winds,
and a tornado or two. SPC continues to show the higher risk for
severe weather for areas generally west of the I-35 corridor.

As the line of convection moves closer to the I-35 corridor Sunday
morning, most of the hi-res models show a gradual weakening trend as
convection moves well ahead of the Pacific front. We will need to
keep an eye on the possibility of some convection re-developing late
tomorrow afternoon, with a low end chance for severe storms along
and north of I-10. Suspect the better chance for additional
development Sunday afternoon will largely remain farther north from
central into northeast Texas.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 221 PM CDT Sat Apr 27 2024

The mid-level pattern remains active as we move into the start of
next week as west-southwesterly flow aloft remains in place through
the beginning of May. There are some notable differences in overall
precip amounts between ensemble members through the period, but for
now, we will hope for continued rainfall, which will hopefully help
to fill up some of our parched reservoirs. PWAT`s are expected to
steadily increase through midweek as low level moisture refuses to
budge. Whether we can actually squeeze some decent rains out of this
moisture remains to be seen. The dryline should remain west of our
CWA starting Tuesday as southwesterly flow aloft takes hold of the
synoptic pattern. Warm, humid mornings, followed by mild and muggy
afternoons will become the norm through at least late week with a
chance for rain and isolated storms for most locations Tuesday-
Friday.

By Friday night, a cold front will attempt to move into the area
from the north, something that will become increasingly rare as we
move into the month of May. If this were to move through the region,
we`d certainly have some decent upper level support to force
widespread showers and isolated storms to develop over the region
next Saturday. For now, we will stick with the NBM PoPs and run with
it as it`s become difficult to pin down timing of precip this
upcoming week.

&&

.AVIATION...
(06Z TAFS)
Issued at 1214 AM CDT Sun Apr 28 2024

Widespread MVFR cigs are in place to begin the period as strong,
moist southeasterly flow funnels into a very long thunderstorm
complex to our N/W. This complex will continue to push into our area
over night, reaching KDRT around 08Z and the I-35 terminals around
13Z. Storms should gradually weaken as they move east, though some
strong to severe storms will be possible at each terminal once they
arrive with hail and strong/variable winds. Conditions should improve
to VFR behind the complex, though moist low level flow and MVFR to
possibly IFR cigs are expected to return early Monday morning.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              82  68  88  69 /  80  10  10  10
Austin Bergstrom Intl Airport  82  68  87  66 /  80  20  20  10
New Braunfels Muni Airport     83  68  88  69 /  70  10  20  10
Burnet Muni Airport            81  65  86  67 /  60  10  10  10
Del Rio Intl Airport           94  67  96  74 /   0   0  10  10
Georgetown Muni Airport        81  66  87  65 /  80  10  10  10
Hondo Muni Airport             87  66  90  68 /  60  10  20  10
San Marcos Muni Airport        82  68  87  67 /  70  20  20  10
La Grange - Fayette Regional   83  70  85  70 /  80  50  30  10
San Antonio Intl Airport       84  69  88  70 /  70  10  20  10
Stinson Muni Airport           85  70  88  71 /  70  10  20  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

Short-Term...Platt
Long-Term...MMM
Aviation...Gale