044
ACUS01 KWNS 191952
SWODY1
SPC AC 191951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Sat Oct 19 2024

Valid 192000Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
EASTERN NEW MEXICO AND FAR WEST TEXAS...

...SUMMARY...
Large hail, severe gusts and some tornado threat are possible across
eastern New Mexico and portions of far West Texas through this
evening.

...20z Update...
The previous forecast remains valid with minimal changes. Widespread
convection is ongoing in multiple meridional bands east of a broad
upper cyclone over the Southwest. Broken cloud cover extends well
north into parts of central CO and UT. This should continue to limit
diurnal heating and low-level lapse rates across the region. As a
result, the thunder area has been trimmed on the northern end where
limited buoyancy and weakening ascent should limit thunderstorm
potential.

Farther south and east, an isolated severe risk will remain possible
with deeper convection ahead of the stalled front. Partial clearing
and continued low-level upslope flow will support scattered to
numerous storms this afternoon and evening. With buoyancy around
1000 J/kg and 40-50 kt of effective shear, a few supercell
structures capable of hail, damaging winds and a brief tornado are
possible. See MCD #2149 for more detailed information.

..Lyons.. 10/19/2024

.PREV DISCUSSION... /ISSUED 1126 AM CDT Sat Oct 19 2024/

...NM into Far West TX...
Morning satellite imagery shows a well-defined cyclone centered over
AZ, with at least one embedded vorticity maximum rotating through
its base. Expectation is for this cyclone to remain largely in place
throughout the period, with the amplified upper ridging downstream
persisting and the stronger westerlies remaining displaced north
along the international border. Strong mid-level flow rotates
cyclonically around this upper low, with enhanced mid-level
southerly flow expected to continue across NM throughout the day.
The southeasterly low-level flow currently ongoing across the
southern High Plains/southern Plains is expected to strengthen as
the gradient between the large eastern CONUS high and the lower
surface pressure in the vicinity of the AZ upper cyclone tightens.
This will contribute to both low-level moisture advection and
strengthening deep-layer vertical shear across the southern High
Plains today.

Thunderstorms are already ongoing from far eastern AZ into western
NM, to the west of the stationary boundary that extends from far
south-central NM/ELP vicinity into northeast NM. The deep-layer flow
across much of this region predominantly southerly, and with the
front-parallel orientation expected to keep these storms west of the
front until later this afternoon. Some heating is still possible
west of the boundary, which could result in enough buoyancy for a
few strong to isolated severe storms capable of damaging gusts and
hail.

During the afternoon and evening, the potential for more warm-sector
is expected to increase, as ascent attendant to a vorticity maximum
rotating through the base of the upper low spreads across the
diurnally destabilized airmass over eastern NM. The combination of
low-level moisture advection and modest diurnal heating will result
in moderate buoyancy, with MLCAPE expected to maximize around
1000-1500 J/kg across east-central/southeast NM. A few discrete
storms appear possible across southeast/south-central NM from around
20Z through 00Z or so. Vertical shear supports supercells and all
severe hazards are possible with these storms, including a tornado
or two. Thunderstorm coverage should increase along the front as
well as it begins to slowly move eastward. A more linear mode is
anticipated with this activity, but a few stronger gusts and
isolated hail are still possible within this band.

$$