SPC Convective Outlook Day 1

See Product Description

905
ACUS01 KWNS 051912
SWODY1
SPC AC 051910

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0210 PM CDT Sat Jul 05 2025

Valid 052000Z - 061200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING FROM SOUTHEAST MONTANA AND NORTHEAST WYOMING INTO
WESTERN SOUTH DAKOTA...

...SUMMARY...
Scattered severe storms are likely across portions of the northern
High Plains this afternoon through the evening. Severe wind gusts
and large hail are the primary hazards.

...20z Update...
The current D1 Convective Outlook remains on track with no updates
needed. See the previous discussion below for more information.

..Thornton.. 07/05/2025

.PREV DISCUSSION... /ISSUED 1058 AM CDT Sat Jul 05 2025/

...Northern High Plains...
Morning water vapor loop shows a shortwave trough progressing into
southern ID. This feature will move across the northern Rockies,
spreading large scale forcing into much of MT this afternoon.
Scattered thunderstorms are expected to form over the mountains of
southwest MT and northern WY during the early/mid afternoon and
spread eastward into a progressively more moist/buoyant air mass.
Easterly low-level winds in the Plains, coupled with favorable
westerly flow aloft will promote supercell storm structures capable
of large hail. Most 12z CAM guidance suggests upscale growth to
bowing segments as storms track across eastern MT/WY into western
SD, with an increasing risk of significant wind damage.

...CO/KS...
Full sunshine is occurring this morning over northeast CO, leading
to afternoon temperatures in the 90s and steep low-level lapse
rates. High-based convection will form off the foothills during the
afternoon and move into this environment that will be favorable for
strong downdrafts. A consensus of morning model guidance suggests a
cluster of storms will evolve from this area, spreading eastward
into western KS this evening. Locally damaging wind gusts will be
possible. Have extended the SLGT risk southward to include this
scenario.

...SC/NC...
Tropical Storm Chantal will track northward today, approaching the
SC coast by early Sunday morning. Forecast soundings suggest that
low-level shear will steadily increase through the night along the
coast of eastern SC and southern NC. Outer rain bands associated
with the system will pose a MRGL risk of tornadoes.

$$

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

017
FLUS43 KLOT 051633
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
1133 AM CDT Sat Jul 5 2025

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-061645-
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-
1133 AM CDT Sat Jul 5 2025 /1233 PM EDT Sat Jul 5 2025/

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

.DAY ONE...This Afternoon and Tonight.

Weather hazards expected...

Elevated Thunderstorm Risk...with an associated:
Level 1 of 5 Damaging Wind Risk...up to 60 mph.
Limited Flooding Risk.

DISCUSSION...

A few storms are expected this evening mainly west of Interstate
39. While widespread severe weather is not expected, an isolated
instance of damaging winds cannot be ruled out. Torrential downpours
will also likely accompany the storms.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Sunday...
Elevated Thunderstorm Risk.
Limited Flooding Risk.
Tuesday night through Thursday...
Limited Thunderstorm Risk.


.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected.

GENERAL STORM MOTION OF THE DAY:

Moving toward the east northeast at 20 to 30 mph.

$$

LMZ740>745-061645-
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-
1133 AM CDT Sat Jul 5 2025

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...This Afternoon and Tonight.

Weather hazards expected...

Hazardous conditions for small craft.
Limited Thunderstorm Risk.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Sunday...
Elevated Thunderstorm Risk.
Wednesday and Thursday...
Limited Thunderstorm Risk.

$$

KJB

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

431
ACUS02 KWNS 051726
SWODY2
SPC AC 051725

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 PM CDT Sat Jul 05 2025

Valid 061200Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
CENTRAL HIGH PLAINS...

...SUMMARY...
Storms may produce severe wind and hail along the central High
Plains on Sunday. A few instances of 2+ inch diameter hail and 75+
mph wind gusts are possible.

...Central Plains...
A shortwave trough will dive southeastward across the northern
Rockies late in the day, with 35-40 kt midlevel wind speeds
extending as far south as northern CO and western NE. Temperatures
aloft will also be cool, resulting in steep lapse rates.

While high pressure will exist over the northern Plains, a gradually
deepening surface trough over the High Plains will lead to westward
moisture advection with mid 50s F dewpoints into eastern WY and CO,
and 60s F just east. Combined with daytime heating and cool profiles
aloft, substantial instability will support severe storms, with
localized significant hail or wind reports.

Storms will form after about 21Z from southeast WY toward the Front
Range, producing large hail. With time, activity may develop into a
severe MCS, proceeding east/southeast into western KS. Aiding
forward propagation will be strengthening southeast winds at 850 mb
after 00Z, with continued unstable storm-relative inflow.

...Maine...
Moderate 40-50 kt midlevel winds will persist over region, perhaps
with a very low amplitude wave skirting across southern Quebec and
Maine during the late afternoon. A slow-moving cold front appears
properly timed to support diurnal storm development, as MUCAPE peaks
at around 1500 J/kg. Given relatively poor lapse rates aloft, but
moderate mean winds, fast-moving cells will be possible, with a few
damaging gusts.

...MO into central IL and IN...
A minor disturbance aloft will affect the region, atop an elongated
surface trough extending from the lower Great Lakes southwestward
into MO. Thunderstorms will develop during the day as the air mass
will remain moist and unstable, with over 2000 J/kg MUCAPE present.
However, overall profiles appear on the cloudy/high RH side, and
boundary layer heating/lapse rates will not be particularly steep.
As such, while gusty outflows will be present with afternoon through
evening, the severe risk seems low. Small hail cannot be ruled out
in the strongest of cells near peak heating.

...Parts of the eastern Carolinas...
Convection associated with TS Chantal will move from eastern SC
across eastern NC during the day, with enhanced low-level wind
fields and 0-1 SRH around 100-150 m2/s2. Given the sufficiently
unstable air mass, this could support an isolated/brief tornado risk
during the day with convection feeding in east of the track.

..Jewell.. 07/05/2025

$$

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

724
ACUS03 KWNS 051925
SWODY3
SPC AC 051924

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0224 PM CDT Sat Jul 05 2025

Valid 071200Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
CENTRAL PLAINS...

...SUMMARY...
Severe storms are possible across the central Plains on Monday.
Severe wind and hail are the main threats. Isolated strong to
potentially severe storms are also possible from parts of New York
into Maine.

...Central to Northern Plains...
A northwest flow regime will become more prominent over the region
on Monday, with 35-40 kt winds at 500 mb. Area of early storms are
possible over parts of KS and NE from previous day activity, but air
mass recovery will occur behind from eastern CO into western NE/KS
with heating. New development may wait until near 00Z or after, but
cells capable of large hail will be possible over a small area.

...Upstate NY into ME...
A moist and unstable air mass will exist over the area, ahead of a
cold front extending from western NY into ME. Daytime heating of
this air mass will support scattered storms, beneath modest 30-40 kt
midlevel winds. This should support fast-moving mixed-mode
convection, with areas of damaging gusts.

..Jewell.. 07/05/2025

$$

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.