No watches are valid as of Fri Oct 30 22:16:02 UTC 2026.MD 2421 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHERN NEVADA INTO WESTERN/CENTRAL ARIZONA
Mesoscale Discussion 2421
NWS Storm Prediction Center Norman OK
0356 PM CDT Fri Oct 30 2026
Areas affected...portions of southern Nevada into western/central
Arizona
Concerning...Severe potential...Watch unlikely
Valid 302056Z - 302300Z
Probability of Watch Issuance...5 percent
SUMMARY...An isolated risk for marginally severe hail, strong to
locally severe wind gusts, and perhaps a landspout may accompany the
strongest storms this afternoon/evening. Watch issuance is not
expected.
DISCUSSION...Convective coverage has gradually increased through 21
UTC ahead of an approaching mid-level shortwave trough evident over
southern California in recent water vapor satellite imagery. While
widespread cloud cover has been prevalent across the region through
much of the day, filtered diurnal heating and dewpoints ranging from
the mid-50s to low-60s F are supporting weak to moderate buoyancy of
500-1000+ J/kg MLCAPE, which has been sufficient for the development
of a few relatively small and transiently stronger convective cores
through mid-afternoon.
Stronger mid/upper flow along the eastern periphery of the
aforementioned shortwave trough (~40 kts at 8-9 km MSL per the
FSX/IWA VWPs) and modest mid-level lapse rates around 7 C/km may
support modestly greater organization of developing updrafts and
isolated marginally severe hail through mid afternoon. Isolated
strong to locally severe wind gusts may also occur, primarily where
stronger heating has steepened low-level lapse rates. Lastly, some
potential for a brief landspout may exist given pockets of stronger
low-level buoyancy overlapping ambient surface vorticity,
particularly in the NV/AZ border vicinity where latest objective
analysis depicts NSTP values of 1-2. Given the overall expectations
for any severe risk to remain limited in magnitude and spatially
isolated, watch issuance is not expected.
..Chalmers/Smith.. 10/30/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TWC...FGZ...PSR...VEF...
LAT...LON 36351503 36391469 36241442 35911410 35341365 34831304
34411222 34251163 34021101 33781065 33441059 33241070
32971128 32991212 33141292 34121418 34941510 35591540
36081529 36351503
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Fri Oct 30 2026
Valid 302000Z - 311200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE MIDDLE
COAST OF TEXAS AND CENTRAL INTO SOUTHERN ARIZONA...
...SUMMARY...
An isolated risk for severe weather is possible today along the
middle coast of Texas and central into southern Arizona.
...20z Update...
...Middle Coast of TX...
The upper trough and associated vorticity maxima noted in the
previous outlook continues to shift northeast. Tornado probabilities
have been trimmed in the wake of this disturbance. A brief tornado
remains possible with any updraft that can take advantage of the
enhanced low-level shear in this region. See MCD #2420 for
additional details.
...Arizona...
Visible satellite trends have shown some filtered insolation in the
wake of the initial band of precipitation this afternoon, resulting
in modest destabilization. Isolated thunderstorms have redeveloped
across portions of northwest Arizona and southern Nevada. Additional
redevelopment should continue farther south, into central/southern
Arizona over the next few hours. Isolated severe hail/winds will be
possible with this activity amid the modest deep-layer shear
environment. Probabilities have been trimmed slightly in southwest
Arizona based on observational trends.
..Karstens.. 10/30/2026
.PREV DISCUSSION... /ISSUED 1119 AM CDT Fri Oct 30 2026/
...Middle Coast of TX...
An upper trough and associated vorticity maximum evident in midday
water-vapor imagery over the Rio Grande Valley will continue
east-northeast and reach the Ark-La-Tex and northwest Gulf Coast by
late evening. A zone of warm advection immediately ahead of the
disturbance will advance northeast up the coast during the
afternoon. The inland penetration of higher theta-e into the
coastal counties may result in sufficient buoyancy for a couple of
stronger updrafts. Some enlargement of the low-level portion of the
hodograph within a moist environment may yield a risk for a brief
tornado near the coast this afternoon.
...Arizona...
A shortwave trough moving into southern CA will continue northeast
towards the Four Corners during the period. Copious mid to
high-level cloud cover will likely limit heating of a seasonably
moist boundary layer across the lower desert. Model guidance
continues to indicate the possibility for a few stronger
thunderstorms developing later today. An isolated risk for
marginally severe hail and localized severe gusts may accompany the
stronger thunderstorms.
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 PM CDT Fri Oct 30 2026
Valid 011200Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
CENTRAL NEW MEXICO INTO WESTERN TEXAS...
...SUMMARY...
A few severe storms are anticipated from parts of central New Mexico
into parts of western Texas late Sunday into Sunday night.
...Synopsis...
Upper troughs within the Great Basin and near the Baja Peninsula
will begin to phase into a broader Southwest trough on Sunday. A
surface low will deepen in the eastern Great Basin and evolve
eastward into central High Plains by Monday morning. A cold front
will move through New Mexico.
...New Mexico...
Cloud cover will be on the increase ahead of the upper level system.
This will lead to some areas not receiving very much surface
heating. The greatest surface heating will likely occur in eastern
New Mexico into the southern High Plains. Low-level moisture will be
maintained by southerly low-level flow. 40s to low 50s F dewpoints
can be expected in much of central New Mexico with low 60s F
possible farther south/east towards the southern High Plains. The
presence of a strong mid-level jet will promote strong wind shear
across the region. While supercells will be possible, linear forcing
from the front may keep the storm mode more linear in nature.
Despite limited buoyancy and the late timing of the activity, the
strong wind fields will support a threat for convectively enhanced
severe wind gusts. Marginally severe hail may also occur conditional
on a supercell storm mode.
..Wendt.. 10/30/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Fri Oct 30 2026
Valid 311200Z - 011200Z
...NO CRITICAL AREAS...
Fire weather concerns will remain low across the CONUS on Day
2/Saturday. A low-amplitude shortwave trough will lift out of TX
into the Mid-South/Southeast with embedded tropical remnants and
Gulf moisture pervading much of the region. Impulses within
southwesterly flow aloft will promote scattered showers where dry
fuels exist in the lower MS River Valley, bringing some relief to a
drought-stressed fuelscape.
..Elizalde-Garcia.. 10/30/2026
.PREV DISCUSSION... /ISSUED 0145 AM CDT Fri Oct 30 2026/
...Synopsis...
A limited overlap of dry and windy conditions atop receptive fuels
will keep fire-weather concerns minimal across the CONUS on
Saturday.
...Please see www.spc.noaa.gov/fire for graphic product...
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