SPC Convective Outlook Day 1

See Product Description

041
ACUS01 KWNS 091631
SWODY1
SPC AC 091630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Mon Mar 09 2026

Valid 091630Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING FROM ARKANSAS TO NORTHWEST GEORGIA...

...SUMMARY...
Large hail, damaging winds and a couple of tornadoes are possible
this afternoon/evening from the Mid-South into northwest Georgia.

...AR to north GA this afternoon/evening...
A weak mid-upper speed max is cresting the larger-scale ridge and
will move from AR to the TN Valley this afternoon/evening.
Associated/ongoing convection across AR will likely persist through
the afternoon with some tendency for upscale growth, while spreading
eastward along the northern gradient of boundary-layer dewpoints in
the low-mid 60s. Surface heating in cloud breaks, beneath the
eastern extent of 7-8 C/km midlevel lapse rates, will contribute to
moderate buoyancy (MLCAPE of 1000-1500 J/kg) along this corridor
with minimal convective inhibition.

Deep-layer vertical shear will be sufficient for a somewhat
organized/bowing storm cluster to evolve from the ongoing AR storms
as they spread across the TN Valley this afternoon, potentially
reaching northwest GA by late evening. The initial storms in the
cluster will pose a threat for large hail (1-2"diameter), with some
increase in the threat for wind damage from northern MS across
northern AL/northwest GA. More discrete storms will be possible
immediately south of the MCS path this afternoon/evening as a
maritime tropical air mass (68-72 F dewpoints) spreads inland. Wind
profiles will support supercells capable of producing large hail
(some could exceed 2 inches in diameter). A modest increase in
low-level shear this afternoon, combined with rich low-level
moisture and the possibility of lingering convective outflow from
the ongoing storms in AR will also support the potential for a
couple of tornadoes.

Isolated thunderstorm development may also occur farther southwest
along the marine warm front into southeast TX, where there is a
conditional threat for large hail.

...Southern AZ this afternoon/evening...
High-based, low-topped convection is expected in the band of ascent
immediately north-northeast of the closed low near northern Baja.
Low-level moisture will be somewhat limited, but steep low-midlevel
lapse rates and substantial south-southeasterly deep-layer shear
will support a few storms/clusters capable of marginally severe hail
and gusts approaching 60 mph.

..Thompson/Chalmers.. 03/09/2026

$$

The "Convective Outlooks" issued by SPC can be thought of as a detailed discussion of the Severe Thunderstorm threat and it's associated risks nationwide. Risk levels range from Marginal to Slight, Enhanced, Moderate, and High and are issued based on the likelihood of 3 major severe weather threats; the risk of tornadoes, damaging winds, and hail. These discussions are often heavily laced meteorological terminology that may be difficult to understand without a background in the field. However understanding these discussions shouldn't be thought of as necessary. Instead, should DuPage county fall under one of these threat levels for severe weather, the response should be to have a heightened level of awareness about the deveoloping weather. Keep an eye on the "Watch County Notification" for any active severe weather watches issued for DuPage county; the "Hazardous Weather Outlook" and "Severe Weather Statement" can also be helpful in explaining the developing risk; additionally, watch for "Active Weather Warnings" and keep an eye on our "Regional Satellite and Radar" products which can be viewed with active watches/warnings or lightning activity.

Hazardous Weather Outlook

See Product Description

628
FLUS43 KLOT 090823
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
323 AM CDT Mon Mar 9 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-100830-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
323 AM CDT Mon Mar 9 2026 /423 AM EDT Mon Mar 9 2026/

This Hazardous Weather Outlook is for portions of north central
Illinois...northeast Illinois and northwest Indiana.

.DAY ONE...Today and Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday...
Elevated Flooding Risk.
Elevated Thunderstorm Risk...with an associated:
Level 3 of 5 Severe Thunderstorm Risk.

DISCUSSION...

Severe thunderstorms will be possible late Tuesday afternoon
into Tuesday evening. A front is expected to be along the
Interstate 80 corridor, with large hail, damaging winds and
tornadoes possible south of this front. North of this front,
large hail will still be possible.

Heavy rain will also be possible late Tuesday afternoon into
early Wednesday morning which may lead to localized flash
flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

$$

LMZ740>745-100830-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
323 AM CDT Mon Mar 9 2026

This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.

.DAY ONE...Today and Tonight.

Weather hazards expected...

Hazardous conditions for small craft this morning.
Limited Fog Risk tonight.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday...
Hazardous conditions for small craft are likely.
Elevated Thunderstorm Risk...with an associated:
Level 3 of 5 Severe Thunderstorm Risk.
Limited Fog Risk.
Wednesday...
Hazardous conditions for small craft are likely.
Thursday and Friday...
Gale force winds and very hazardous waves.
Saturday and Sunday...
Hazardous conditions for small craft are likely.

$$

Visit us at www.weather.gov/chicago

The "Hazardous Weather Outlook" contains information regarding any and all weather expected to occur within the region that could be hazardous to travel, life or property. This is one of our most highly recommended products to check on a daily basis, and it some cases multiple times per day should significant weather be expected to affect DuPage county.

SPC Convective Outlook Day 2

See Product Description

782
ACUS02 KWNS 090601
SWODY2
SPC AC 090600

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Mon Mar 09 2026

Valid 101200Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS
NORTHEAST MISSOURI...FAR SOUTHEAST IOWA...AND PARTS OF
NORTHERN/CENTRAL ILLINOIS INTO NORTHWEST INDIANA...

...SUMMARY...
Scattered severe thunderstorms are forecast on Tuesday from the
southern Plains into the southern Great Lakes vicinity. All severe
hazards are possible.

...Synopsis...

A complex scenario for severe thunderstorm potential is expected on
Tuesday and Tuesday night from the Southern Plains to the Mid-MS
Valley/southern Great Lakes vicinity. A somewhat bi-modal severe
risk appears possible within a split-flow upper level pattern. All
severe hazards appear possible, especially within a corridor across
portions of TX, and a second corridor from northern MO into
northern/central IL and northwest IN.

Expansive area of enhanced southwesterly flow will overspread the
southern Plains into the Upper Great Lakes, aided by two separate
upper troughs. The first is associated with an upper low/trough
across northwest Mexico and the Southwest, which will shift east
into the southern High Plains by Wednesday. The second is a broad
but deepening upper trough moving across the northern/central Plains
toward the Upper Midwest. Two areas of low pressure are expected to
develop with the approaching of these upper systems, one over the
central/southern High Plains and the other across the Lower
MO/Mid-MS valley. A dryline/Pacific front will be oriented across
western TX, while a warm front extends west to east from near
northern MO/southeast IA into northern IL/IN. By evening, a cold
front will begin to develop southeast across KS/MO/IA/IL/IN, and the
Pacific front will shift east across central TX. These boundaries
will be the focus for scattered to widespread thunderstorm
development from late afternoon into the overnight hours.

...Mid-MO Valley to southern Great Lakes vicinity...

Capping will likely suppress convection for much of the day within a
strong warm advection regime. Surface dewpoints are expected to
climb into the low/mid-60s south of the warm front beneath steep
midlevel lapse rates. This will foster 1000-2000 J/kg MLCAPE by peak
heating. Convection is expected to develop within the 21-00z time
frame when a 40 kt low-level jet is expected to overspread the
region. Supercell wind profiles are noted in forecast soundings,
with hodographs exhibiting enhanced low-level curvature, with
lengthened/straight hodographs above 2-3 km. Given a favorable
thermodynamic environment, large hail to 2.5 inches appears possible
with storms both within the warm sector and initial activity that
may develop within the cooler air north of the front. Furthermore,
any cells that develop within the warm sector and interact with the
front will encounter enhanced low-level shear/SRH and tornadoes
(some EF-2+) will be possible. With time during the evening,
convection will likely grow upscale into one or more
southeast-advancing linear segments near the advancing cold front.
Damaging winds will be possible with this activity overnight.

...Southern Plains vicinity...

Convection is expected to develop along the surface dryline across
western TX by mid to late afternoon. Initial supercells are possible
and could produce large hail (to around 2 inch diameter) and a
couple of tornadoes. Convection may quickly grow upscale as the
Pacific front overtakes the dryline and large-scale ascent increases
rapidly by 00z.

Uncertainty increases with northward extent across OK/KS into
southern MO/AR. These areas will be within the broad warm sector and
moderate to strongly sheared environment. However, this area will
also be between the two areas of stronger ascent. Some capping may
persist and it is unclear how convection may evolve across these
areas.

..Leitman.. 03/09/2026

$$

The "Convective Outlooks" issued by SPC can be thought of as a detailed discussion of the Severe Thunderstorm threat and it's associated risks nationwide. Risk levels range from Marginal to Slight, Enhanced, Moderate, and High and are issued based on the likelihood of 3 major severe weather threats; the risk of tornadoes, damaging winds, and hail. These discussions are often heavily laced meteorological terminology that may be difficult to understand without a background in the field. However understanding these discussions shouldn't be thought of as necessary. Instead, should DuPage county fall under one of these threat levels for severe weather, the response should be to have a heightened level of awareness about the deveoloping weather. Keep an eye on the "Watch County Notification" for any active severe weather watches issued for DuPage county; the "Hazardous Weather Outlook" and "Severe Weather Statement" can also be helpful in explaining the developing risk; additionally, watch for "Active Weather Warnings" and keep an eye on our "Regional Satellite and Radar" products which can be viewed with active watches/warnings or lightning activity.

SPC Convective Outlook Day 3

See Product Description

528
ACUS03 KWNS 090721
SWODY3
SPC AC 090720

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0220 AM CDT Mon Mar 09 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE ARKLATEX
AND LOWER MISSISSIPPI VALLEY NORTHEAST THROUGH THE OHIO VALLEY...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible on Wednesday
from the ArkLaTex and Lower Mississippi Valley northeastward through
the Ohio Valley vicinity.

...East Texas northeast to the Ohio Valley vicinity...

A split-flow regime will continue into Wednesday, with upper
troughing over the central U.S. remaining bifurcated through much of
the period. In the southern branch, a closed low/upper shortwave
trough will migrate from TX to the Lower MS Valley. Meanwhile, the
northern stream upper trough over the northern Plains/Upper Midwest
will develop east across the Upper Great Lakes/Midwest. Ahead of
these features, strong southwesterly deep-layer flow will extend
from east TX into the Mid-Atlantic/New England. At the surface, a
cold front will extend southwest from a surface low over southern
Lower MI into western OK. This front will advance southeast through
the period, becoming oriented from the Mid-Atlantic coast to the
central Gulf coast by Thursday morning.

Strong warm advection ahead of the front will transport Gulf
moisture as far north as the Mid-Atlantic and southern New England.
Ongoing convection is expected ahead of the front across portions of
the ArkLaTex into the Midwest. This, along with the warm advection
regime resulting in widespread cloudiness, lends to uncertainty in
how the downstream airmass will destabilize, especially with
northeast extent into parts of the Ohio Valley vicinity. Somewhat
stronger destabilization is likely across the Lower MS Valley where
richer Gulf moisture will reside. Strong vertical wind profiles will
support damaging wind potential with even modest instability. Linear
convection is the most likely storm mode given deep-layer flow
parallel to the surface boundary and strong large-scale ascent
overspreading the boundary. If discrete cells can form, some tornado
potential will exist closer to a deepening surface cyclone in the
vicinity of the upper Ohio Valley, and perhaps near a secondary
surface low over the lower MS Valley, though this scenario remains
highly uncertain.

..Leitman.. 03/09/2026

$$

The "Convective Outlooks" issued by SPC can be thought of as a detailed discussion of the Severe Thunderstorm threat and it's associated risks nationwide. Risk levels range from Marginal to Slight, Enhanced, Moderate, and High and are issued based on the likelihood of 3 major severe weather threats; the risk of tornadoes, damaging winds, and hail. These discussions are often heavily laced meteorological terminology that may be difficult to understand without a background in the field. However understanding these discussions shouldn't be thought of as necessary. Instead, should DuPage county fall under one of these threat levels for severe weather, the response should be to have a heightened level of awareness about the deveoloping weather. Keep an eye on the "Watch County Notification" for any active severe weather watches issued for DuPage county; the "Hazardous Weather Outlook" and "Severe Weather Statement" can also be helpful in explaining the developing risk; additionally, watch for "Active Weather Warnings" and keep an eye on our "Regional Satellite and Radar" products which can be viewed with active watches/warnings or lightning activity.

Special Weather Statement

See Product Description

No active Special Weather Statement for DuPage County.

The "Special Weather Statement" details notable weather either occuring or expected to occur, but does not necessarily have to be considered severe or hazardous. This is a supplementary product issued by the National Weather Service to help describe noteworthy weather. It's terminology should be reasonably easy to understand by the general public.

Watch County Notification

See Product Description

No active Watch County Notification for DuPage County.

The "Watch County Notification" will contain updates regarding active severe weather watches that pertain to DuPage county. This may be for a newly issued watch, or the cancelation of an existing watch. Severe weather watches come in two forms; Severe Thunderstorm and Tornado, and it should be noted that a Severe Thunderstorm Watch does NOT rule out the possibility of tornadoes occuring. It generally means that the tornado threat is minimal while damaging winds and hail are still likely. See our "Watch, Warning, and Advisory Criteria" for more detailed information on the differences and critera for watches, warnings and advisory for all forms of weather.

Winter Weather Statement

See Product Description

No active Winter Weather Statement for DuPage County.

The "Winter Weather Statement" is a product aimed at the general public that will discuss impacts caused by winter weather. This may include information about watches, warnings and advisories as well as details about impactful winter weather that may not warrant the issuance of a watch, warning or advisory.

Severe Weather Statement

See Product Description

No active Severe Weather Statement for DuPage County.

The "Severe Weather Statement" is a product aimed at the general public that will discuss impacts caused by severe thunderstorms. This may include information about watches and warnings as well as details about impactful "sub-severe" weather that may not warrant the issuance of a watch or warning which sometimes may come when a watch or warning has been canceled.

Non-Precip Statement

See Product Description

No active Non-Precip Statement for DuPage County.

The "Non-Precip Statement" is aimed at the general public and will detail notable weather that is either occuring or expected to occur, but does not relate to any form of precipitation. These would include but are not limited to high winds, reduced visibility or extreme temperatures.

Active Weather Warnings

Tornado Warnings

No active Tornado Warnings.

Severe Thunderstorm Warnings

No active Severe Thunderstorm Warnings.

Flood Warnings

No active Flood Warnings.

General Tornado/Severe Weather Safety

1. A Tornado or Severe Thunderstorm Warning is issued when it has been reported, or when it has been detected via National Weather Service radar. It is to be interpreted that this event is occuring and is expected to affect all warned areas. Those within the warning need to take action immediately.
2. If under a warning remain calm and if it is necessary to seek shelter. Students and Employees should head to their nearest designated shelter area. The route to these shelter areas are posted in all rooms on campus and signs are placed in the hallways to direct you to the nearest shelter area. Review these instructions and be familiar with where your nearest shelter is. Stay indoors, away from windows and large unsupported ceilings. Faculty should account for their students and Supervisors should account for their areas employees.
3. If outside, take shelter in the nearest building.
4. After the storm has passed, dial Police at 911 to report any injuries or damage to buildings.
5. If the building is severely damaged, evacuate the building as soon as possible after the storm has passed.