Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0712 PM CDT Thu Oct 31 2024

Valid 010100Z - 011200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are unlikely through Friday morning.

Scattered thunderstorms persist this evening near a weak surface
trough extending from far southern TX into LA and MS. These storms
remain in a weakly sheared environment, well south of the shortwave
trough moving across the upper Great Lakes. While the environment is
moist and marginally unstable, severe weather is therefore unlikely.

..Jewell.. 11/01/2024

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0254 PM CDT Thu Oct 31 2024

Valid 312000Z - 011200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms appear unlikely this afternoon and evening.

...20z Update...
The Marginal risk across the Southeast was removed with this update.
Storms have largely been sub-severe and disorganized, as low-level
flow remains weak. In addition, thunder chances were removed from
the Pacific Northwest.

..Thornton/Gleason.. 10/31/2024

.PREV DISCUSSION... /ISSUED 1129 AM CDT Thu Oct 31 2024/

...ArkLaTex into the Lower Mississippi Valley and Mid-South...
A small area of low wind probabilities has been maintained with this
update from northeast TX to western TN. An ongoing, loosely
organized squall line will continue to move east-southeastward this
afternoon across parts of the ArkLaTex and lower MS Valley.
Widespread cloud cover is hindering daytime heating to some extent,
and poor mid-level lapse rates should also limit the degree of
MLCAPE available for convection. The stronger low/mid-level flow
associated with an ejecting cyclone over the Upper Midwest/Great
Lakes is expected to remain displaced well to the north of the
ongoing convection through this afternoon. While modest deep-layer
shear will exist across the lower MS Valley vicinity, the overall
severe wind threat will likely remain muted by weak instability.
Further reduction and/or removal of the Marginal Risk will be
considered with the next scheduled update (20Z).

...Ohio Valley/Great Lakes...
Destabilization ahead of an eastward-moving cold front is forecast
to remain rather limited this afternoon. While stronger
low/mid-level flow will be present over the OH Valley and Great
Lakes in association with an ejecting upper trough, potential for
gusty winds with thunderstorms should remain low.

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0202 PM CDT Thu Oct 31 2024

Valid 021200Z - 031200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TEXAS
PANHANDLE VICINITY SOUTH TO THE PERMIAN BASIN AREA...

...SUMMARY...
Scattered thunderstorms -- along with potential for locally
strong/severe storms capable of producing hail and strong wind gusts
-- are expected Saturday across portions of the central and southern
Plains, focused on the southern High Plains area of western Texas.

...Synopsis...
Continued amplification of the large-scale pattern aloft is expected
Saturday, as the deepening trough progresses eastward across the
West.  At the surface, an attendant cold front will continue
crossing the Intermountain region, emerging into the High Plains
overnight.

...Southern High Plains to western Kansas, central Oklahoma, and
central Texas...
Substantial low-level theta-e advection is forecast to continue
across the central and southern Plains Saturday, as the upper trough
advances and mid-level height falls ahead of the trough support a
broad area of enhanced low-level southerlies.  The southerlies
through the lower troposphere, beneath increasing mid-level
southwesterlies ahead of the upper system, will result in a broad
region where deep-layer shear will be sufficient for organized
storms.

In conjunction with daytime heating of the moistening airmass,
destabilization across eastern New Mexico and Texas will occur, with
500 to locally 1500 J/kg mixed-layer CAPE expected.  Though
low-level foci for ascent will be subtle, ongoing/locally robust
convection early in the period should persist -- and perhaps expand
in coverage through the day, and then continue through the evening
and into the overnight hours.  Primary risks with the stronger
storms will be hail and locally damaging wind gusts.  While the
overall area where the background environment will be sufficient to
support some severe risk will be rather broad, at this time is
appears that the greatest CAPE/shear combination will reside over
western portions of Texas, from the Panhandle south to the Permian
Basin.

..Goss.. 10/31/2024

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1225 PM CDT Thu Oct 31 2024

Valid 011200Z - 021200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE SOUTHERN HIGH PLAINS...

...SUMMARY...
Scattered thunderstorms, a few which may become capable of marginal
hail/wind, will likely evolve across parts of the southern High
Plains Friday evening into the overnight.

...Synopsis...
Broadly cyclonic flow aloft will persist over the western half of
the country Friday, amplifying with time as short-wave energy
initially off the West Coast digs south-southeastward toward
northern California through the period.

At the surface, a cold front will shift across the Northwest and
into the Great Basin and California, in tandem with the digging
upper feature.  Meanwhile, a remnant/west-to-east baroclinic zone
will persist from the southeastern U.S. westward into the southern
Plains.

...Southern High Plains...
Ahead of the amplifying western U.S. upper trough, weak mid-level
height falls will support a zone of low-level warm advection across
the southern High Plains vicinity.  Afternoon heating of a gradually
moistening low-level airmass will result in modest destabilization,
with 500 to 1000 J/kg mixed-layer CAPE expected.  Little nocturnal
decrease in instability is expected, as low-level theta-e advection
supported by persistent surface southeasterlies should offset any
diurnal cooling effects.  

Given the modest but sufficient CAPE expected by afternoon, ascent
should support gradual development of isolated to scattered storms
-- initially in the vicinity of higher terrain.  Aided by
veering/moderately increasing flow with height, shear should support
multicell organization and potentially some mid-level rotation.  As
such, risk for hail and/or wind reaching severe criteria exists
locally, with a couple of the strongest storms.  This potential
should continue overnight, with a northward/northwestward expansion
of convection as the low-level theta-e advection increases in tandem
with a strengthening south-southeasterly low-level jet.

..Goss.. 10/31/2024

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1129 AM CDT Thu Oct 31 2024

Valid 311630Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
EAST TEXAS INTO THE LOWER MISSISSIPPI VALLEY/MID-SOUTH...

...SUMMARY...
Isolated strong thunderstorms capable of producing occasional wind
gusts remain possible today from parts of east Texas into the lower
Mississippi Valley and Mid-South.

...ArkLaTex into the Lower Mississippi Valley and Mid-South...
A small area of low wind probabilities has been maintained with this
update from northeast TX to western TN. An ongoing, loosely
organized squall line will continue to move east-southeastward this
afternoon across parts of the ArkLaTex and lower MS Valley.
Widespread cloud cover is hindering daytime heating to some extent,
and poor mid-level lapse rates should also limit the degree of
MLCAPE available for convection. The stronger low/mid-level flow
associated with an ejecting cyclone over the Upper Midwest/Great
Lakes is expected to remain displaced well to the north of the
ongoing convection through this afternoon. While modest deep-layer
shear will exist across the lower MS Valley vicinity, the overall
severe wind threat will likely remain muted by weak instability.
Further reduction and/or removal of the Marginal Risk will be
considered with the next scheduled update (20Z).

...Ohio Valley/Great Lakes...
Destabilization ahead of an eastward-moving cold front is forecast
to remain rather limited this afternoon. While stronger
low/mid-level flow will be present over the OH Valley and Great
Lakes in association with an ejecting upper trough, potential for
gusty winds with thunderstorms should remain low.

..Gleason/Kerr.. 10/31/2024

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0747 AM CDT Thu Oct 31 2024

Valid 311300Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
ARKLATEX/LOWER MISSISSIPPI VALLEY/LOWER OHIO VALLEY...

...SUMMARY...
A few strong to locally severe storms capable of wind gusts are
possible today from parts of the Ohio Valley southwestward into
east/northeast Texas.

...Lower Ohio Valley/Mid-South and ArkLaTex/East Texas...
An extensive northeast/southwest-oriented squall line (650 miles
long), with considerable trailing stratiform precipitation, extends
from the Wabash River/Lower Ohio River southwestward into the middle
of Arkansas toward the ArkLaTex and broader parts of northeast Texas
at daybreak. This activity squall has been sub-severe in the predawn
hours, but some re-intensification is possible into the afternoon as
the boundary layer warms ahead of the slow-east/southeastward-moving
squall line and effective front.

Regionally, stronger flow aloft/deep-layer shear will reside across
the Mid-South/Tennessee Valley into the Ohio Valley where
destabilization will be rather weak. Stronger instability will exist
southwestward across east Texas/ArkLaTex into the Lower Mississippi
Valley (as per 12Z Little Rock AR observed sounding). However, a
mid-level subsidence inversion will also tend to exist (sampled by
12Z Shreveport LA observed sounding), with a weakening low-level
wind field through the day. As such, only isolated marginally severe
wind gusts are expected regionally. Any such severe risk should
diminish by around sunset.

..Guyer/Leitman.. 10/31/2024

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0354 AM CDT Thu Oct 31 2024

Valid 031200Z - 081200Z

...DISCUSSION...
...Sunday/Day 4 and Monday/Day 5...
An upper-level trough is forecast to move across the Desert
Southwest on Sunday, as the exit region of a broad mid-level jet
overspreads the southern and central Plains. Ahead of the system, a
moist airmass will likely be in place. Scattered thunderstorms are
expected to develop within this moist airmass Sunday afternoon as
instability increases during the day. Surface dewpoints in the 60s
F, low-end moderate instability and moderate to strong deep-layer
shear should support severe thunderstorm development Sunday
afternoon and evening. The greatest severe potential is expected
from north Texas northward into south-central Nebraska, where large
hail, severe wind gusts and an isolated tornado threat will be
possible. 

On Monday, the trough is forecast to move into the southern High
Plains, as a 80 to 90 knot mid-level jet translates through the
eastern part of the system. Ahead of the trough, pockets of moderate
instability are forecast to develop across a moist airmass during
the day. Thunderstorms that form in the afternoon across the western
part of the moist sector are expected to have potential for large
hail and wind damage.

...Tuesday/Day 6 to Thursday/Day 8...
From Tuesday to Thursday, an upper-level trough is forecast to move
quickly eastward across the northern U.S., as a cold front advances
southeastward across the eastern third of the U.S. Warming surface
temperatures ahead of the front should result in scattered
thunderstorm development each afternoon and evening. The greatest
severe threat could be on Tuesday in the lower to mid Mississippi
Valley near the entrance region of the mid-level jet. The severe
threat could re-develop ahead of the front on Wednesday and
Thursday. However, instability is forecast to be weak suggesting
that any severe threat should be marginal.

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0225 AM CDT Thu Oct 31 2024

Valid 021200Z - 031200Z

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

...SUMMARY...
Thunderstorms, associated with large hail and wind damage, are
expected to develop across parts of the southern High Plains on
Saturday. A marginal severe threat will also be possible outside of
the Slight Risk area in parts of the southern and central Plains.

...Southern and Central Plains...
An upper-level trough will move eastward across the western U.S. on
Saturday, as southwest mid-level flow remains from the Intermountain
West eastward into the Great Plains. A moist airmass will be in
place across the southern and central Plains, where scattered
thunderstorms will likely develop during the day. The strongest
instability is forecast across parts of eastern New Mexico and west
Texas by mid to late afternoon. Thunderstorms that develop in this
area during the late afternoon and evening could be associated with
a severe threat. NAM forecast soundings across west Texas by
00Z/Sunday suggest that MLCAPE will peak in the 1500 to 2000 J/kg
range. 0-6 km shear is forecast to increase into the 40 to 50 knot
range as a mid-level jet of around 50 knots moves into the southern
High Plains. In addition, 700-500 mb lapse rates in West Texas are
forecast to be from 7 to 7.5 C/km by early Saturday evening. This
should be favorable for supercells associated with large hail and
severe wind gusts. The models currently suggest that a severe threat
could be of rather long duration, with one round of storms
developing across west Texas early in the day, and a second round of
storms developing in the evening or overnight period. As these
clusters move eastward into the Low Rolling Plains of west-central
Texas and into western and central Oklahoma, the threat should
become more isolated.

Further north, from the Oklahoma Panhandle northward into western
Kansas, moisture and instability are gradually forecast to increase
Saturday night. Weak instability and moderate deep-layer shear,
evident on forecast soundings, could support a marginal threat for
hail and severe wind gusts with the greatest threat toward the end
of the period.

..Broyles.. 10/31/2024

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1244 AM CDT Thu Oct 31 2024

Valid 011200Z - 021200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN HIGH PLAINS...

...SUMMARY...
Thunderstorms, associated with isolated large hail and marginally
severe wind gusts, will be possible across parts of the southern
High Plains Friday evening into the overnight.

...Southern High Plains...
An upper-level trough will dig southeastward across the Pacific
Coastal states on Friday, as flow remains southwesterly at
mid-levels across much of the western and central U.S. Moisture
advection will take place across the southern Plains on Friday, with
surface dewpoints increasing into the 60s F over much of Texas. By
late Friday afternoon, a pocket of moderate instability is expected
over parts of West Texas and southeast New Mexico. Scattered
thunderstorms appear likely to develop during the early evening near
this pocket of instability. As moisture and low-level flow gradually
increase across the southern Plains from the evening into the
overnight, convective coverage is expected to expand north and
northeastward across much of eastern New Mexico and west Texas.

A consensus of model forecasts suggests that MLCAPE will peak around
1500 J/kg in parts of west Texas Friday evening. 0-6 km shear is
forecast to be in the 30 to 40 knot range. The moderate deep-layer
shear, combined with 700-500 mb lapse rates near 7 C/km, should
support the development of a severe threat.  Most of the cells are
expected to remain multicellular. However, areas where the
environment is locally more favored could support supercells with
isolated large hail and a few severe wind gusts. The late initiation
and lack of large-scale ascent is expected to be a limiting factor,
and should keep any severe threat marginal.

..Broyles.. 10/31/2024

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0755 PM CDT Wed Oct 30 2024

Valid 310100Z - 311200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
AND NORTHEAST OKLAHOMA INTO WESTERN MISSOURI...

...SUMMARY...
Severe storms capable of severe winds and a few tornadoes remain
possible in a zone from central into northeast Oklahoma and into
western Missouri. A few destructive wind gusts can be anticipated.

...Discussion...
Storms continue to evolve along a cold front this evening, most
notably from north-central OK into southeast KS and into northwest
MO. Shear remains strong across the entire region, with low-level
shear supportive of rotation maximized beneath the low-level jet
from eastern OK into MO. The 00Z OUN sounding shows a supercell
hodograph especially for storms moving rightward off the
front/boundary.

Given the upper trough position, large-scale ascent appears to be
most favorable through late evening from northeast OK into western
MO, while farther south, ascent will be more heavily dependent on
the surface cold front, especially into northern TX tonight.

Damaging winds appear to be the most likely severe mode given storms
oriented/congealed along the boundary. However, embedded/QLCS type
tornadoes will be possible given such favorable low-level shear.
Overall instability is not particularly strong due to modest
midlevel lapse rates, but is clearly sufficient given other
favorable factors. 

For more information see mesoscale discussions 2169, 2170, and 2171.

..Jewell.. 10/31/2024