SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1020 AM CST Tue Dec 23 2025
Valid 231630Z - 241200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
COASTAL CALIFORNIA...
...SUMMARY...
An isolated threat for severe/damaging gusts and perhaps a brief
tornado may develop late tonight/early Wednesday morning across
parts of coastal California.
...California...
Within large-scale upper troughing over the eastern Pacific, an
embedded mid-level shortwave trough will move quickly eastward and
approach the CA Coast late tonight/early Wednesday morning. A
corresponding strengthening and increase in the flow through much of
the troposphere is anticipated late in the period, with a surface
low also forecast to deepen along/near the coast of northern CA. A
cold front attendant to this surface low will sweep quickly
eastward, and should be approaching/onshore across parts of coastal
northern/central CA by 12Z early Wednesday morning. Current
expectations are for the thermodynamic profile to remain mostly
saturated, with poor lapse rates generally limiting instability.
Even so, it appears that a gradual increase in low-level moisture
ahead of the cold front and slightly cooling mid-level temperatures
with the approach of the shortwave trough may support weak but
sufficient MUCAPE for an organized band of low-topped thunderstorms
late tonight.
Most guidance suggests this convection will not impact parts of
coastal CA until after 24/06Z, and there is still significant
uncertainty whether enough boundary-layer instability will be
present to support surface-based convection. There is also a signal
for pre-frontal convection in the low-level warm advection regime
across parts of central into coastal southern CA. Given the strength
of the low/mid-level flow forecast, and related strong
low-level/deep-layer shear, it appears that convectively enhanced
winds may be capable of reaching severe levels and producing damage
on an isolated basis even if instability remains minimal. A brief
tornado may also occur if convection can become truly surface based,
as effective SRH will be enhanced by a 50-70 kt southerly low-level
jet. Based on latest guidance trends, the Marginal Risk has been
expanded southward along the coast to include more of
central/southern CA. This isolated severe threat is expected to
continue beyond 12Z Wednesday into the Day 2 period.
..Gleason/Thornton.. 12/23/2025
Read more
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0659 AM CST Tue Dec 23 2025
Valid 231300Z - 241200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS NEAR THE COAST
OF NORTHERN CALIFORNIA...
...SUMMARY...
A localized threat for severe gusts may develop late tonight near
the coast in northern California.
...CA...
A potent shortwave trough is forecast to approach the northern CA
coast late tonight as an attendant midlevel speed max moves from the
eastern Pacific into northern CA. Considerable differences were
noted in some of the latest models with the 00z EC/UKMET operational
runs considerably weaker with cyclone development than 00-06z runs
of the NAM/GFS/Canadian and the 00z HREF mean. Hedging towards a
slightly more intense forecast solution and related wind field
depictions. This forecast scenario coincides with a surface front
surging inland toward the end of the period, around 24/12z. Although
pre-frontal buoyancy will remain quite limited (100-200
J/kg MUCAPE), the deeper low-topped convection may yield a
severe-wind risk during the 08-12z period near the immediate coast
before buoyancy diminishes inland.
...South TX...
Weak midlevel disturbance is lifting north into deep south TX late
this evening. Forecast soundings suggest modest SBCAPE will develop
by mid day as this feature progresses north of the international
border. Wind fields should remain weak, along with forcing, so the
risk of severe is expected to remain low this period.
..Smith/Weinman.. 12/23/2025
Read more
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0659 AM CST Tue Dec 23 2025
Valid 231300Z - 241200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS NEAR THE COAST
OF NORTHERN CALIFORNIA...
...SUMMARY...
A localized threat for severe gusts may develop late tonight near
the coast in northern California.
...CA...
A potent shortwave trough is forecast to approach the northern CA
coast late tonight as an attendant midlevel speed max moves from the
eastern Pacific into northern CA. Considerable differences were
noted in some of the latest models with the 00z EC/UKMET operational
runs considerably weaker with cyclone development than 00-06z runs
of the NAM/GFS/Canadian and the 00z HREF mean. Hedging towards a
slightly more intense forecast solution and related wind field
depictions. This forecast scenario coincides with a surface front
surging inland toward the end of the period, around 24/12z. Although
pre-frontal buoyancy will remain quite limited (100-200
J/kg MUCAPE), the deeper low-topped convection may yield a
severe-wind risk during the 08-12z period near the immediate coast
before buoyancy diminishes inland.
...South TX...
Weak midlevel disturbance is lifting north into deep south TX late
this evening. Forecast soundings suggest modest SBCAPE will develop
by mid day as this feature progresses north of the international
border. Wind fields should remain weak, along with forcing, so the
risk of severe is expected to remain low this period.
..Smith/Weinman.. 12/23/2025
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CST Tue Dec 23 2025
Valid 261200Z - 311200Z
...DISCUSSION...
From Friday/Day 4 to Sunday/Day 6, a mid-level ridge is forecast to
move eastward from the central U.S. to the Eastern Seaboard. During
this time, a trough is forecast to develop in the Pacific Northwest,
and then to dig southeastward into the mid Mississippi Valley. An
associated cold front is forecast to move southeastward into the
Ohio and Tennessee Valleys by Sunday afternoon. Ahead of the front,
surface dewpoints in the 60s F should result in weak destabilization
with thunderstorm development possible along the front. However, the
models suggest that most of the convection will be post-frontal.
This limitation should keep any severe threat marginal.
On Monday/Day 7 and Tuesday/Day 8, the trough is forecast to move
across the eastern U.S. into the western Atlantic, with the front
moving off the Atlantic coast. In its wake, a relatively dry and
cool airmass will make thunderstorm development unlikely across most
of the nation.
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CST Tue Dec 23 2025
Valid 261200Z - 311200Z
...DISCUSSION...
From Friday/Day 4 to Sunday/Day 6, a mid-level ridge is forecast to
move eastward from the central U.S. to the Eastern Seaboard. During
this time, a trough is forecast to develop in the Pacific Northwest,
and then to dig southeastward into the mid Mississippi Valley. An
associated cold front is forecast to move southeastward into the
Ohio and Tennessee Valleys by Sunday afternoon. Ahead of the front,
surface dewpoints in the 60s F should result in weak destabilization
with thunderstorm development possible along the front. However, the
models suggest that most of the convection will be post-frontal.
This limitation should keep any severe threat marginal.
On Monday/Day 7 and Tuesday/Day 8, the trough is forecast to move
across the eastern U.S. into the western Atlantic, with the front
moving off the Atlantic coast. In its wake, a relatively dry and
cool airmass will make thunderstorm development unlikely across most
of the nation.
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CST Tue Dec 23 2025
Valid 261200Z - 311200Z
...DISCUSSION...
From Friday/Day 4 to Sunday/Day 6, a mid-level ridge is forecast to
move eastward from the central U.S. to the Eastern Seaboard. During
this time, a trough is forecast to develop in the Pacific Northwest,
and then to dig southeastward into the mid Mississippi Valley. An
associated cold front is forecast to move southeastward into the
Ohio and Tennessee Valleys by Sunday afternoon. Ahead of the front,
surface dewpoints in the 60s F should result in weak destabilization
with thunderstorm development possible along the front. However, the
models suggest that most of the convection will be post-frontal.
This limitation should keep any severe threat marginal.
On Monday/Day 7 and Tuesday/Day 8, the trough is forecast to move
across the eastern U.S. into the western Atlantic, with the front
moving off the Atlantic coast. In its wake, a relatively dry and
cool airmass will make thunderstorm development unlikely across most
of the nation.
Read more
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0215 AM CST Tue Dec 23 2025
Valid 251200Z - 261200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF
THE CENTRAL AND SOUTHERN CALIFORNIA COAST...
...SUMMARY...
Thunderstorms with marginally severe wind gusts and perhaps a brief
tornado, will be possible on Thursday along parts of the central and
southern California Coast.
...California...
A large-scale mid-level trough will move slowly eastward toward the
California coast on Thursday. Strong flow aloft will maintain a
stream of mid-level moisture into the region, as large-scale ascent
continues to support scattered thunderstorm development. At the
surface, a cold front will approach the central California coast
during the day. Surface dewpoints ahead of the front will be in the
50s F, southward into parts of southern California. This should be
enough for weak destabilization near the coast during the late
morning and afternoon, which could result in a marginal severe
threat. Strong low to mid-level flow and modestly steep low-level
lapse rates could support isolated severe wind gusts and perhaps a
brief tornado.
..Broyles.. 12/23/2025
Read more
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0215 AM CST Tue Dec 23 2025
Valid 251200Z - 261200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF
THE CENTRAL AND SOUTHERN CALIFORNIA COAST...
...SUMMARY...
Thunderstorms with marginally severe wind gusts and perhaps a brief
tornado, will be possible on Thursday along parts of the central and
southern California Coast.
...California...
A large-scale mid-level trough will move slowly eastward toward the
California coast on Thursday. Strong flow aloft will maintain a
stream of mid-level moisture into the region, as large-scale ascent
continues to support scattered thunderstorm development. At the
surface, a cold front will approach the central California coast
during the day. Surface dewpoints ahead of the front will be in the
50s F, southward into parts of southern California. This should be
enough for weak destabilization near the coast during the late
morning and afternoon, which could result in a marginal severe
threat. Strong low to mid-level flow and modestly steep low-level
lapse rates could support isolated severe wind gusts and perhaps a
brief tornado.
..Broyles.. 12/23/2025
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0118 AM CST Tue Dec 23 2025
Valid 241200Z - 251200Z
...Synopsis...
A mid-level ridge will persist across the central U.S., with a
highly amplified mid-level trough poised to gradually drift eastward
across the Interior West tomorrow (Wednesday). Lee troughing across
the High Plains will intensify through the day, promoting a modestly
stronger surface wind field across the southern High Plains compared
to Day 1. 15 mph sustained westerly surface winds will coincide with
15-20 percent RH during the afternoon across northeast New Mexico
into the Texas Panhandle and far southwestern Kansas. Given dry
fuels over this region, Elevated highlights have been introduced.
..Squitieri.. 12/23/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0118 AM CST Tue Dec 23 2025
Valid 241200Z - 251200Z
...Synopsis...
A mid-level ridge will persist across the central U.S., with a
highly amplified mid-level trough poised to gradually drift eastward
across the Interior West tomorrow (Wednesday). Lee troughing across
the High Plains will intensify through the day, promoting a modestly
stronger surface wind field across the southern High Plains compared
to Day 1. 15 mph sustained westerly surface winds will coincide with
15-20 percent RH during the afternoon across northeast New Mexico
into the Texas Panhandle and far southwestern Kansas. Given dry
fuels over this region, Elevated highlights have been introduced.
..Squitieri.. 12/23/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0118 AM CST Tue Dec 23 2025
Valid 231200Z - 241200Z
...NO CRITICAL AREAS...
...Synopsis...
Upper ridging will remain in place east of the Rockies while a
highly amplified mid-level trough impinges on the West Coast today.
Surface lee troughing will encourage moisture return across the
Plains states, with relatively drier air meandering along the
immediate lee of the Rockies. Surface winds along the southern into
central High Plains will be relatively weak on a large-scale basis
though, with wildfire-spread concerns remaining localized at best.
..Squitieri.. 12/23/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0118 AM CST Tue Dec 23 2025
Valid 231200Z - 241200Z
...NO CRITICAL AREAS...
...Synopsis...
Upper ridging will remain in place east of the Rockies while a
highly amplified mid-level trough impinges on the West Coast today.
Surface lee troughing will encourage moisture return across the
Plains states, with relatively drier air meandering along the
immediate lee of the Rockies. Surface winds along the southern into
central High Plains will be relatively weak on a large-scale basis
though, with wildfire-spread concerns remaining localized at best.
..Squitieri.. 12/23/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CST Tue Dec 23 2025
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF
THE CALIFORNIA COAST AND INLAND IN THE SAN JOAQUIN VALLEY...
...SUMMARY...
Thunderstorms with marginally severe wind gusts, hail and
potentially a brief tornado will be possible from Wednesday into
Wednesday night along parts of the California coast, and inland
across the San Jouquin Valley.
...California...
A ridge aloft will move eastward across the central U.S. on
Wednesday, as a mid-level trough moves eastward across the eastern
Pacific. Ahead of this large-scale feature, a subtle shortwave
trough will approach the California coast Wednesday afternoon. As
heights gradually fall, large-scale ascent and mid-level moisture
will overspread most of California during the day. Thunderstorm
development will be possible along the central and southern
California coast, and inland across the San Joaquin Valley. The
greatest chance for severe storms will be as the left exit region of
a 90 to 100 knot mid-level jet moves across the San Joaquin Valley
during the mid to late afternoon. Near this feature, very strong
deep-layer shear will exist and MUCAPE is expected to peak in the
500 to 750 J/kg range. This should be enough for a few
semi-organized storms with a threat for hail and marginally severe
gusts. A brief tornado will also be possible. An isolated severe
threat is expected to continue into the overnight period, and may
shift southward along the coast into southern California, as a
second minor impulse approaches and moves inland.
..Broyles.. 12/23/2025
Read more
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1119 PM CST Mon Dec 22 2025
Valid 231200Z - 241200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorm potential will increase along the California coast late
tonight. Organized severe is not currently forecast.
...CA...
Strong short-wave trough is forecast to approach the northern CA
coast after 24/06z, then eject inland by sunrise as midlevel speed
max intensifies and translates into northern CA. Latest model
guidance suggests this feature will induce a surface low that should
deepen as it approaches the northern CA/OR coast. This evolution
will allow a notable surface front to surge inland toward the end of
the period, around 24/12z. Wind profiles are expected to increase
markedly ahead of this feature, but pre frontal buoyancy will remain
quite limited. Forecast soundings support this with roughly 100-200
J/kg MUCAPE expected just ahead of the front. Given the strength of
the wind field there is some concern that a few strong gusts could
be noted with deeper convection; however, this activity should
develop very late (after 09z), possibly becoming more problematic
during the day2 period. At this time will not introduce severe
probabilities due to the expected late-period development, but will
continue to monitor for possible upgrade.
...South TX...
Weak midlevel disturbance is lifting north into deep south TX late
this evening. Forecast soundings suggest modest SBCAPE will develop
by mid day as this feature progresses north of the international
border. Wind fields should remain weak, along with forcing, so the
risk of severe is expected to remain low this period.
..Darrow/Squitieri.. 12/23/2025
Read more
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1119 PM CST Mon Dec 22 2025
Valid 231200Z - 241200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorm potential will increase along the California coast late
tonight. Organized severe is not currently forecast.
...CA...
Strong short-wave trough is forecast to approach the northern CA
coast after 24/06z, then eject inland by sunrise as midlevel speed
max intensifies and translates into northern CA. Latest model
guidance suggests this feature will induce a surface low that should
deepen as it approaches the northern CA/OR coast. This evolution
will allow a notable surface front to surge inland toward the end of
the period, around 24/12z. Wind profiles are expected to increase
markedly ahead of this feature, but pre frontal buoyancy will remain
quite limited. Forecast soundings support this with roughly 100-200
J/kg MUCAPE expected just ahead of the front. Given the strength of
the wind field there is some concern that a few strong gusts could
be noted with deeper convection; however, this activity should
develop very late (after 09z), possibly becoming more problematic
during the day2 period. At this time will not introduce severe
probabilities due to the expected late-period development, but will
continue to monitor for possible upgrade.
...South TX...
Weak midlevel disturbance is lifting north into deep south TX late
this evening. Forecast soundings suggest modest SBCAPE will develop
by mid day as this feature progresses north of the international
border. Wind fields should remain weak, along with forcing, so the
risk of severe is expected to remain low this period.
..Darrow/Squitieri.. 12/23/2025
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0627 PM CST Mon Dec 22 2025
Valid 230100Z - 231200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorm probabilities are low tonight.
...01z Update...
Water-vapor imagery depicts a notable short-wave trough advancing
inland along the Pacific Northwest coast. A few flashes of lighting
have been observed with deeper convection ahead of this feature,
primarily across more buoyant regions offshore. While an isolated
thunderstorm can not be ruled out for the next few hours, lightning
probabilities appear too low to warrant a categorical risk of
thunderstorms the rest of tonight.
Lighting has decreased notably across the western Gulf basin in
association with a weak disturbance lifting north toward deep South
TX. 00z sounding at BRO does exhibit uninhibited SBCAPE, but loss of
daytime heating and weak forcing does not appear particularly
favorable for more than a rogue flash of lightning, and that is
primarily over the next few hours.
..Darrow.. 12/23/2025
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0627 PM CST Mon Dec 22 2025
Valid 230100Z - 231200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorm probabilities are low tonight.
...01z Update...
Water-vapor imagery depicts a notable short-wave trough advancing
inland along the Pacific Northwest coast. A few flashes of lighting
have been observed with deeper convection ahead of this feature,
primarily across more buoyant regions offshore. While an isolated
thunderstorm can not be ruled out for the next few hours, lightning
probabilities appear too low to warrant a categorical risk of
thunderstorms the rest of tonight.
Lighting has decreased notably across the western Gulf basin in
association with a weak disturbance lifting north toward deep South
TX. 00z sounding at BRO does exhibit uninhibited SBCAPE, but loss of
daytime heating and weak forcing does not appear particularly
favorable for more than a rogue flash of lightning, and that is
primarily over the next few hours.
..Darrow.. 12/23/2025
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0347 PM CST Mon Dec 22 2025
Valid 241200Z - 301200Z
...Synopsis...
An upper-level ridge over the central U.S. should begin to deamplify
through the end of the week as an mid/upper trough gradually moves
into Intermountain West. Well above normal temperatures under the
ridge will likely be daily occurrences with minimal precipitation
expected, particularly across the southern Great Plains where
expanding rainfall deficits, dry fuels and dry and breezy conditions
could align to support an increased fire weather threat. A
descending upper-level trough into the Northeast along with a
deepening surface cyclone should drive a strong cold front through
the Great Plains and eastern U.S. over the weekend. Precipitation
should be limited to the TN Valley/Appalachians region where deeper
boundary layer moisture and stronger upper-level support exists. A
more diffuse surface pressure gradient and generally lighter wind
regime emerges as high pressure settles in east of the Continental
Divide early next week although initial dry post-frontal flow could
reinvigorate a fire weather threat across the southern Plains and TX
early next week.
...Day 3-5/Wednesday-Friday - Southern Plains...
Lee troughing across the Central Plains and persistent southwesterly
flow aloft will promote dry and breezy conditions across the OK/TX
Panhandle and northeastern NM on Day 3/Wednesday. Deeper return flow
moisture from the Gulf will limit fire weather concerns to the
southern High Plains Wednesday. A breakdown in the upper-level ridge
across the central U.S. along with increasing west-southwest flow
aloft will continue to support breezy conditions across the southern
High Plains Thursday. A plume of Pacific moisture and mid/upper
cloud cover associated with an impinging western U.S. trough should
arrive Day 4/Thursday across the Southern High Plains. Additional
cloud cover, increasing surface dewpoints and limited RH reductions
could limit the fire weather threat to an extent, but near record
warmth along with an increasingly dry fuelscape and breezy
west-southwest winds supports introduction of 40% critical
probabilities for Thursday for portions of the TX Panhandle and far
eastern NM. Increasing west/southwest flow aloft from a mid-level
jet and continued lee troughing should keep a dry downslope regime
across the southern Plains through Day 5/Friday. A better boundary
layer mixing environment with less cloud cover and persistently warm
temperatures should support low daytime RH across the Southern
Plains Friday. A 40% critical probability area was added to cover
this likely fire weather concern across far eastern NM and portions
of the TX Panhandle.
...Days 6-8/Saturday-Monday...
Some forecast uncertainty remains in the timing and intensity of
pre/post-frontal winds across the central and southern Plains over
the weekend. This could present ongoing fire weather threats across
the south-central CONUS and even the Southeast where minimal
rainfall and above normal temperatures allow more receptive fuels to
develop through early next week. Critical probabilities were
withheld due to ongoing uncertainty and longer term ensemble
guidance.
..Williams.. 12/22/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
