SPC Convective Outlook Day 1

See Product Description

546
ACUS01 KWNS 050506
SWODY1
SPC AC 050504

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1104 PM CST Wed Feb 04 2026

Valid 051200Z - 061200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorm probabilities appear less than 10 percent across the
U.S. today through tonight.

...Discussion...
Downstream of a significant, progressive short wave trough, models
indicate that an initially vigorous perturbation across the southern
mid-latitude Pacific will be forced northeastward/eastward toward
the North American Pacific coast today through tonight. As it
approaches a prominent mid/upper high which has evolved inland of
the U.S coast, it is forecast to split, with one of the emerging
perturbations accelerating toward the British Columbia coast while
the other digs toward the southern California coast. Downstream of
the latter impulse, broader weak troughing initially offshore of
southern California and Baja is forecast to slowly accelerate
north/northeastward inland of coastal areas.

While models indicate that the blocking ridge will probably undergo
notable weakening today through tonight, it appears that amplified
ridging will generally be maintained across the Canadian/U.S.
Rockies, with another significant short wave trough of Arctic
origins digging downstream, across the southwestern Hudson Bay
vicinity. It appears that this will be accompanied by a deepening
surface cyclone, with a trailing cold front advancing across the
international border into portions of the Upper Midwest and Great
Lakes region by late tonight.

This is likely to occur coincident with strong downstream surface
cyclogenesis, offshore of the south Atlantic Seaboard through the
southern mid-latitude western Atlantic, trailed by a cold front
advancing south of the Florida peninsula through the Bahamas and
western Caribbean.

...Florida...
Inland of the Gulf coast, across the remainder of the central and
southern peninsula, with the mid-level cold core continuing to trail
to the northwest of the surface cold front, and mid/upper support
for ascent perhaps weakening ahead of the front, forecast soundings
indicate minimal potential for pre-frontal thunderstorm development
today.

...Southwest...
Model forecast soundings, particularly the Rapid Refresh, suggest
that steepening lower/mid-tropospheric lapse rates and moisture
return from the subtropical eastern Pacific, may lead to the
development of weak conditional instability across parts of southern
California through the Mojave Desert/lower Colorado Valley by late
tonight. However, this may mostly occur in the wake of an initial
short wave impulse overspreading the region, with little potential
for thunderstorm activity through 12Z Friday.

..Kerr.. 02/05/2026

$$

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

268
FLUS43 KLOT 042049
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
249 PM CST Wed Feb 4 2026

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-052100-
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-
249 PM CST Wed Feb 4 2026 /349 PM EST Wed Feb 4 2026/

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

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Thursday...
Limited Snow Risk.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

$$

LMZ740>745-052100-
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-
249 PM CST Wed Feb 4 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...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Friday...
Gale force winds are possible, mainly over the Indiana
nearshore.
Saturday...
Hazardous conditions for small craft are likely.

$$

Carlaw

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

458
ACUS02 KWNS 041637
SWODY2
SPC AC 041636

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1036 AM CST Wed Feb 04 2026

Valid 051200Z - 061200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorms are not forecast on Thursday or Thursday night.

...Discussion...
Conditions will be too dry/stable for lightning-producing convection
across the CONUS through the period.

..Grams.. 02/04/2026

$$

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

695
ACUS03 KWNS 041843
SWODY3
SPC AC 041843

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
1243 PM CST Wed Feb 04 2026

Valid 061200Z - 071200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorm potential generally appears low on Friday and Friday
night.

...Southwest...
Multiple minor shortwave impulses should gradually evolve within a
broad, low-amplitude trough shifting inland from the West Coast.
Moisture for lightning-producing appears rather limited inland of
coastal southern CA, yielding insufficient buoyancy for thunderstorm
probabilities at or above 10 percent over the Mojave Desert and
Lower CO Valley. Still, most 12Z guidance indicates late-day
convective potential over the western Transverse Ranges. Scant
buoyancy amid 500-mb temperatures near -22 C, along with
orographically augmented weak ascent, might foster a couple
thunderstorms.

..Grams.. 02/04/2026

$$

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.