285
FXUS64 KEWX 020546 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1246 AM CDT Thu May 2 2024

...New AVIATION...

.UPDATE...
Issued at 905 PM CDT Wed May 1 2024

First round of storms advanced across Blanco county through the I-35
corridor from near Austin through Williamson county producing very
healthy rainfall rates and some flooding. The storms also strengthen
enough to where some hail and strong winds were possible as well.

Updated the PoPs given the latest observational/radar trends and a
slightly better initiation with the 00Z HRRR. A secondary round for
strong to severe convection and locally heavy rainfall is expected
to develop across the Hill Country and spread eastward into the I-35
corridor and eventually the coastal plains. An uptick in the radar
trends recently across the Hill Country seems to support this idea.
Locally heavy rainfall and flooding remains the greater concern, but
some individual cells could become severe with damaging winds and
large hail as the primary. severe hazards. Have trimmed the PoPs to
the west, especially closer to the Rio Grande. Severe Thunderstorm
Watch remains in effect through 2 AM CDT and a Flash Flood Watch
through 7 AM CDT Thursday for portions of South-Central Texas.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 209 PM CDT Wed May 1 2024

Key Points

* Isolated to scattered strong to severe storms are possible this
  afternoon through tonight with wind and hail the main threats.
  Isolated tornado can`t be ruled out.
* Heavy rainfall and flooding will possible for the eastern two-
  thirds of the area.
* Flood Watch has been issued for portions of the Hill Country, I35
  corridor, and Coastal Plains.

Mostly cloudy skies prevail across South-Central Texas this
afternoon with temperatures in the 70s to lower 80s. Winds remain
out of the southeast with speeds near 10-15 mph on average. Starting
to see an uptick of shower activity across the area and as we
progress into the afternoon, high-res model guidance is all
consistently showing this activity growing in coverage and
intensity. Some of this should bring some locally heavy rainfall and
the possibility of a strong storms this afternoon and evening. The
WRF/ARW suite of the high res models are much more bullish with rain
amounts than the HRRR with some values near 5-7 inches in isolated
places this afternoon. The 18z HRRR shows some pockets of 1-3 inches
with the afternoon activity and think this solution should be the
most favored one. However, even with the light returns on radar,
activity is very efficient rain producers given PW values near 2
inches which is off nearly unheard of for this time of year.

The focus for shower and thunderstorm activity late this evening and
overnight will be out west as convection in West Texas possibly
moves into the northern two-thirds of the area. Could see some
severe storms with this activity with wind gusts then hail as the
main risks. Heavy rainfall will also be possible with this activity
with additional rainfall totals of 1-3 inches likely with some
possible isolated higher amounts.

We issued a Flood Watch earlier for portions of the Hill Country,
I35 corridor, and Coastal Plains through 7 AM. Given this moist
airmass it will not take much to produce heavy rainfall and will
likely see some locations see isolated amounts near 5 inches and
this could produce some flash flooding.

All activity should be mostly east of the forecast area after 10 AM
tomorrow with just some possible very isolated activity continuing
tomorrow during the day. Highs tomorrow will be in the 80s for most
areas with some mid 90s near the Rio Grande. Lows tonight and
tomorrow night will be in the middle 60s to middle 70s.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 209 PM CDT Wed May 1 2024

A shallow upper level trough over the southwest will keep
southwesterly flow over TX through the end of the week. A series of
shortwave troughs will move through this pattern. Combined with
daytime heating this will generate chances for showers and
thunderstorms each afternoon and evening Friday and Saturday. Sunday
the upper pattern will become progressive and the trough will push
into west TX. This will mean chances for convection through the day
Sunday. None of this activity looks strong nor any rainfall
excessive. A low amplitude ridge will push up from the Gulf bringing
dry weather. This ridge will settle over the region for the first
half of next week. This will lead to warming temperatures with highs
reaching the lower to middle 90s over the eastern half of the CWA and
upper 90s to near 105 over the west.

&&

.AVIATION...
(06Z TAFS)
Issued at 1224 AM CDT Thu May 2 2024

A complex of strong to severe thunderstorms are moving across the
Hill Country while pushing to the northeast. Some activity at the
tail end of this feature could clip KAUS within the next hour or two.
Therefore, included a TEMPO group with -TSRA for KAUS. In addition,
low cigs at IFR category are forecast overnight into the middle of
the morning for KAUS. Similar situation apply for KSAT and KSSF where
IFR cigs are expected to prevail overnight through at least 18Z
Thursday. MVFR cigs return sometime in the mid to late afternoon.
KDRT sits at MVFR but around dawn lowering to IFR. MVFR cigs return
late morning with cigs lifting to VFR by 17Z. Southeasterly flow 5 to
10 knots are forecast to prevail through the forecast period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              83  71  86  71 /  50  20  20  20
Austin Bergstrom Intl Airport  83  71  85  70 /  60  20  20  20
New Braunfels Muni Airport     85  72  87  71 /  40  10  20  10
Burnet Muni Airport            82  70  84  69 /  30  20  20  20
Del Rio Intl Airport           96  76  97  74 /  10   0  30  20
Georgetown Muni Airport        82  71  84  70 /  50  20  20  20
Hondo Muni Airport             85  70  89  70 /  10  10  20  10
San Marcos Muni Airport        84  71  86  69 /  50  10  20  20
La Grange - Fayette Regional   84  73  85  72 /  60  20  20  10
San Antonio Intl Airport       84  72  87  72 /  20  10  20  20
Stinson Muni Airport           86  73  89  72 /  20  10  20  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 7 AM CDT this morning for Bandera-Bastrop-Bexar-
Blanco-Burnet-Caldwell-Comal-De Witt-Fayette-Gillespie-Gonzales-
Guadalupe-Hays-Karnes-Kendall-Kerr-Lavaca-Lee-Llano-Travis-
Williamson-Wilson.

&&

$$

Short-Term...17
Long-Term...18
Aviation...17