Mesoscale Discussion 2420
NWS Storm Prediction Center Norman OK
0138 PM CDT Fri Oct 30 2026

Areas affected...parts of mid/upper Texas coastal areas

Concerning...Severe potential...Watch unlikely 

Valid 301838Z - 302045Z

Probability of Watch Issuance...5 percent

SUMMARY...Shower and thunderstorm activity overspreading the mid to
upper Texas coastal plain through 3-5 PM CDT may be accompanied by
low probabilities for a brief/weak tornado, mainly near immediate
coastal areas.

DISCUSSION...Downstream of a weakening mid-level cyclonic vorticity
center slowly migrating north-northeast of the lower Rio Grande
Valley, a focused area of low-level forcing for ascent, supported by
weak low-level convergence and warm advection, is overspreading
middle Texas coastal areas near Palacios.  Preceding a subsident,
lower/mid-tropospheric dry slot, moist thermodynamic profiles
characterized by weak conditional instability have been supporting a
northeastward spreading area of mostly weak convection.  However,
this has included discrete cells with weak to occasionally modest
embedded low-level updraft rotation offshore of coastal areas, where
near-surface buoyancy is boosted by lower/mid 70s surface dew
points, in the presence of small, but clockwise-curved, low-level
hodographs.

With the progression of the larger-scale mid-level troughing, this
environment may develop closer to mid/upper Texas coastal areas
between Palacios and Galveston over the next few hours accompanied
by some risk for a brief, weak tornado.  But, this activity appears
unlikely to spread inland beyond immediate coastal areas, where a
slightly cooler/drier boundary-layer will probably be maintained.

..Kerr/Smith.. 10/30/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...HGX...CRP...

LAT...LON   28629654 29099523 29169497 28679490 28319624 28629654 

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1119 AM CDT Fri Oct 30 2026

Valid 301630Z - 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.

...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.

..Smith/Chalmers.. 10/30/2026

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.

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1213 PM CDT Fri Oct 30 2026

Valid 311200Z - 011200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected on Saturday.

...Synopsis...
A low-amplitude shortwave trough will progress along the Gulf Coast.
Farther west, an upper trough will deepen within the Great Basin
with another shortwave tough approaching the Baja Peninsula.

Scattered storms are expected within a weak warm advection regime
from east Texas into the Mid South and lower Mississippi Valley
vicinity. The strongest activity will likely remain offshore. Cold
temperatures aloft and minimal buoyancy will support isolated
thunderstorm activity within portions of the northern Great Basin.
Early morning thunderstorm activity will also be possible within a
zone of modest warm advection from southeast South Dakota into
eastern Iowa. Little to no severe risk is expected Saturday given
the poor thermodynamic environment.

..Wendt.. 10/30/2026

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

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1136 AM CDT Fri Oct 30 2026

Valid 301700Z - 311200Z

...NO CRITICAL AREAS...

The upper pattern is categorized by broad upper troughing over the
western CONUS, prevailing northwest flow from the Upper Midwest into
the Mid-Atlantic, and a mid-level ridge over the Southeast.
Widespread precipitation is expected today across the Greater Four
Corners region into the Great Plains, while dry conditions will
linger for one more day in the Mid-South amid light surface winds.
As a result, fire weather concerns are reduced across the CONUS.

..Elizalde-Garcia.. 10/30/2026

.PREV DISCUSSION... /ISSUED 0145 AM CDT Fri Oct 30 2026/

...Synopsis...
Fire-weather concerns will remain minimal across the CONUS today,
given widespread precipitation and a limited overlap of dry and
windy conditions.

...Please see www.spc.noaa.gov/fire for graphic product...

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...