512
FXUS64 KSJT 171133
AFDSJT

Area Forecast Discussion
National Weather Service San Angelo TX
633 AM CDT Mon Jun 17 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 212 AM CDT Mon Jun 17 2024

On Water Vapor satellite imagery, an upper level trough can be seen
over the Pacific Northwest, while upper level ridging existed across
Texas. As we go through today and tonight, the trough will push
east into Montana/Idaho/Wyoming, while upper level ridging will
remain in place across Texas and the eastern CONUS. At the
surface, a north to south oriented dry-line will stretch from the
NM/TX Border south through the Big Bend region. Hi-res models
indicate some storms forming along the dry-line this
afternoon/early evening, but those storms should stay west of our
forecast area. Meanwhile, strong surface low pressure across
eastern CO and surface high pressure to the east of us will
continue to bring a strong surface pressure gradient to the
region, causing continued gusty southeasterly winds (15-25 mph
with gusts of 35-40 mph) today and tonight. Finally, expect
similar highs and lows today/tonight (highs in the low to mid 90s
east, and upper 90s to around 100 west; lows in the low to mid
70s), as the 850 mb thermal ridge stays at around the same
strength.

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 354 AM CDT Mon Jun 17 2024

The main focus for the long term portion of the forecast continues
to be the chances for heavy rainfall for the mid to late work week
period (Wednesday through Friday), with a focus on Thursday.

Early Tuesday morning, high-resolution guidance is indicating the
potential for a few showers to develop across the southern Permian
Basin/Trans Pecos region and move east into the Concho
Valley/Northern Edwards Plateau. Chances are still very low overall
so have left PoPs below mentionable in the forecast. Gusty southeast
winds will continue through the day on Tuesday with the strong
surface low across the North Central Plains keeping the pressure
gradient decently tight across western portions of Texas. This will
continue to reinforce the presence of low level moisture across the
area which should keep highs a few degrees cooler in the 90s.

Lots of uncertainty remains in regard to the forecast for Wednesday
through Friday. Models have not come into agreement any more than
they were roughly 24 hours ago and still have vastly different
solutions. There is agreement that a tropical system is expected to
form over the next day or 2 across the southwestern Gulf of Mexico
(highlighted by NHC forecasts showing a 60-70% chance of development
over the next 2-3 days). A large swath of tropical moisture will
surge ahead of this deep into Texas. Highly anomalous pWat values in
the 1.75-2.25 inch range are forecast over much of West Central
Texas by Thursday. For context, this is .75-1 inch over what is
expected for our area. This is where the model similarities largely
end. ECMWF ensembles have continued to show a more westerly track of
the tropical system, likely due to the axis of the upper ridge
across the eastern CONUS extending well into Texas. This would shunt
much of the precipitation into South Central Texas and Northern
Mexico, leaving our area with little to no beneficial rainfall. GFS
ensembles show a more northwesterly track for the system allowing
for an abundance of rainfall across our area with many solutions
showing 3 to 9 inches of rain for areas south of the I-20 corridor,
peaking across our far south/southeastern counties. The track of the
system will ultimately decide how much rain our area receives and
with no real consensus in the track at this time, it`s incredibly
difficult to say with certainty which outcome appears more likely.
Will continue with a blended solution capping PoPs between 40-60%,
with the highest values during the day on Thursday along and south
of the I-10 corridor. There will likely be significant updates in
regards to this forecast over the next few days. We will see if
guidance comes into better agreement in regards to track before
advertising possible QPF amounts across the area. With these chances
for rain and increased moisture/cloud cover across the area, highs
Wednesday and Thursday will be well below normal in the upper 70s to
mid 80s.

The system is expected to exit to the west/northwest through the day
on Friday with rain chances coming to an end by 00Z Saturday. By
late Saturday, an elongated, east-west oriented ridge will be
overhead, keeping the forecast for the weekend dry. Highs by Sunday
will be back to right around normal in the mid to upper 90s with
plenty of sunshine. Lows through the duration of the forecast period
should hold in the upper 60s to mid 70s.

&&

.AVIATION...
(12Z TAFS)
Issued at 633 AM CDT Mon Jun 17 2024

Through 15Z, MVFR CIGs around 1500-2500 ft AGL expected to
continue to move into an area south and east of roughly a Sterling
City to KCOM line, impacting KSJT, KJCT, KSOA and KBBD. 15Z today
through 06Z Tues, VFR conditions expected. 06Z Tues through 12Z
Tues, MVFR CIGs moving up again into roughly the same areas as
this morning. Gusty SE winds expected through 12Z Tues, at
generally 12-16 KT with gusts of 18-25 KT, except during the 13Z
today to 01Z Tues time-frame, when stronger wind speeds of 15-22
KT with gusts of 27-34 KT expected.

&&

.PRELIMINARY POINT TEMPS/POPS...
Abilene     94  74  92  71 /   0   0   0   0
San Angelo  99  75  97  72 /   0   0   0   0
Junction    97  74  95  72 /   0   0   0   0
Brownwood   91  74  90  71 /   0   0   0  10
Sweetwater  96  74  95  71 /   0   0   0   0
Ozona       96  74  95  72 /   0   0   0   0
Brady       93  74  90  70 /   0   0   0   0

&&

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

$$

SHORT TERM...SJH
LONG TERM....50
AVIATION...SJH