-- Discussion containing changed information from previous version are highlighted. --
573
FXUS64 KSJT 161845
AFDSJT

Area Forecast Discussion
National Weather Service San Angelo TX
145 PM CDT Sun Jun 16 2024

...New SHORT TERM...

.SHORT TERM...
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(This evening through Monday)
Issued at 142 PM CDT Sun Jun 16 2024

Most of the state of Texas is between the 500mb subtropical ridge
across northwest Mexico and the 500mb ridge along the middle
Atlantic United States coastline. This will provide a shear axis
across the central and eastern portions of the state tonight into
Monday. The question tonight into early Mon morning is whether any
convection will develop across west Texas tonight and propagate into
portions of west central Texas similar to last night. The latest
HRRR does prog some thunderstorms developing across west Texas
this evening and outflow from this convection may provide a focus
for showers and thunderstorms to develop across portions of the
northern Edwards Plateau late tonight into early Monday morning.
Will mention a slight chance of showers and thunderstorms across
southwest portions of the CWA tonight into early Monday as a
result. Breezy conditions are expected to prevail tonight into
Monday as the pressure gradient remains relatively strong across
west Texas. Temperatures will continue to remain above normal
Monday afternoon.
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&&

.LONG TERM...
(Monday through Saturday)
Issued at 312 AM CDT Sun Jun 16 2024

...Warm and windy start to the long-term with a much cooler and
wetter pattern anticipated by late in the work week...

By Monday, an upper level ridge will strengthen across the
eastern/southeastern CONUS. West Central Texas will be on the far
left edge of this regime but this should act to keep any shortwave
impulses off to our north and west. As such, the rinse-and-repeat
pattern of late will continue into the day on Monday. Temperatures
will range from the lower 90s across the Heartland to the upper
90s/around 100 across the western Concho Valley under partly to
mostly clear skies. Winds will be gusty out of the southeast as a
strong surface low develops across the North Central Rockies,
tightening the pressure gradient for much of the Central and
Southern Plains. This will serve to reinforce the low level
moisture that has been prevalent across our area during the late
spring/early summer. The gusty southeast winds will continue into
Tuesday and with more moisture in place, highs will be a few
degrees "cooler" than Monday with highs in the upper 80s to mid
90s. The western Concho Valley will remain the warm place with
highs still potentially climbing into the upper 90s.

A significant pattern change will be possible by mid to late week. A
tropical disturbance is expected to form in the southwestern Gulf of
Mexico over the next 4 days. The aforementioned upper ridge will
begin to rotate and spread west into the central US by mid-week,
pushing the upper level jet to the north. With widespread weak
easterly flow across the southern US, this will allow for the
tropical system to migrate north and east. A wave of deep, tropical
moisture is expected to push into our area ahead of this, creating
prime antecedent conditions for potentially heavy rainfall. There
is still significant differences in the track of this system in
both probabilistic and deterministic guidance. The latest 00Z
operational runs of GFS and ECMWF highlight these differences with
the GFS taking a more northerly track, allowing our area to take
advantage of the deep moisture in place. The ECMWF shows a much
more southerly track, keeping the bulk of beneficial rainfall
south of us across South Central Texas and Northern Mexico. In any
case, there will be a plethora of moisture to work with as pWat
values are forecast to be in the 2+ inch range across the entirety
of our area by Thursday (an anomaly of between .75-1.25 inches
for this time of year). Have stuck with the model blend at this
time that has capped PoPs at between 40-50% across our southern
counties for Thursday. The track of the system will play a crucial
role in how much rain we actually see across our area Wednesday
through Friday. Given the depth and abundance of moisture, any
showers or storms would likely be prolific rainfall producers so
there would be a risk of flash flooding. As such, WPC has put
southern portions of our area in their Day 5 (Thursday) Slight
Risk for excessive rainfall. Should a more northerly track become
the more likely option, this would likely need to be further
upgraded. Changes in QPF and overall rain chances will be likely
over the next few days so stay tuned for further refinements and
updates to the forecast. These rain chances will cool temperatures
for the end of the week with highs by Thursday in the lower 80s
areawide.

The tropical system looks to exit to the west during the day Friday
with rain chances ending across the region overnight into Saturday.
Temperatures will start back up on a warming trend with highs in the
90s by the weekend and dry conditions expected. Lows through the
entire long-term should stay in the upper 60s to mid 70s.

&&

.AVIATION...
(18Z TAFS)
Issued at 1206 PM CDT Sun Jun 16 2024

Satellite and radar images as well as surface observations
indicate isolated to scattered convection across portions of Coke
County early this afternoon. Otherwise...skies were mostly clear
across the rest of the CWA except across portions of the northwest
Hill Country and the Heartland where mid level clouds continue to
develop. Ceilings were near 3200ft at KBBD. Expect MVFR conditions
with isolated showers/thunderstorms across portions of the Concho
Valley this afternoon. Otherwise...expect VFR conditions to
prevail across west central Texas the rest of the afternoon into
this evening as the weak 500mb shortwave trough across northwest
Texas moves eastward and subsidence increases across the CWA with
northwest flow aloft.

&&

.PRELIMINARY POINT TEMPS/POPS...
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Abilene     74  94  73  92 /   0   0   0   0
San Angelo  74  99  74  98 /   0   0   0   0
Junction    74  97  74  95 /   0   0   0   0
Brownwood   74  91  73  89 /   0   0   0   0
Sweetwater  74  97  73  94 /   0   0   0   0
Ozona       73  96  72  95 /  20  20   0   0
Brady       73  92  73  89 /   0   0   0   0
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&&

.SJT WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...61
LONG TERM....50
AVIATION...61