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Current Conditions

A message from COD Meteorology

Current Local Radar

Temperature
81°F
Feels Like:
84°F
Dew Point	Humidity
68°F	66%

Fair

Wind Strength
Light	Moderate	Strong
West-southwest at 6 mph GUST: 11mph

Local Graphical Forecast (Updated: 07/18/25 4:12 pm)

Friday (7/18)
Day	Night


High	Low
	68

Saturday (7/19)
Day	Night

60%	30%
High	Low
85	69

Sunday (7/20)
Day	Night

30%	40%
High	Low
78	65

Monday (7/21)
Day	Night

30%	20%
High	Low
83	68

Tuesday (7/22)
Day	Night


High	Low
90	74

Wednesday (7/23)
Day	Night


High	Low
95	75

Thursday (7/24)
Day	Night


High	Low
93	72

Detailed Text Forecast (Updated: 07/18/25 4:12 pm)

Friday Night: Partly cloudy, with a low around 68. South wind around 5 mph becoming east southeast in the evening.

Saturday: A chance of showers and thunderstorms before 10am, then showers likely and possibly a thunderstorm between 10am and 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 85. South wind 5 to 10 mph becoming west in the afternoon. Winds could gust as high as 15 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Saturday Night: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 69. West wind 5 to 10 mph becoming north northeast after midnight.

Sunday: A 30 percent chance of showers and thunderstorms, mainly before 1pm. Mostly cloudy, with a high near 78. Northeast wind 5 to 10 mph.

Sunday Night: A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 65. Northeast wind 5 to 10 mph.

Monday: A 30 percent chance of showers and thunderstorms before 1pm. Mostly cloudy, with a high near 83.

Monday Night: A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 68.

Tuesday: Partly sunny, with a high near 90.

Tuesday Night: Partly cloudy, with a low around 74.

Wednesday: Mostly sunny and hot, with a high near 95.

Wednesday Night: Mostly clear, with a low around 75.

Thursday: Mostly sunny, with a high near 93.

Thursday Night: Partly cloudy, with a low around 72.

Friday: A chance of showers and thunderstorms. Mostly sunny, with a high near 89.

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SPC Convective Outlook Day 1

See Product Description

430
ACUS01 KWNS 181926
SWODY1
SPC AC 181924

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0224 PM CDT Fri Jul 18 2025

Valid 182000Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS INTO THE MIDWEST AND PARTS OF THE MID-ATLANTIC...

...SUMMARY...
Scattered severe thunderstorms with large hail, damaging winds, and
a couple of tornadoes are possible across parts of the Corn Belt in
Iowa, Minnesota, Nebraska, and South Dakota this evening into
tonight. Scattered damaging winds are possible across parts of
Virginia and North Carolina this afternoon.

...20Z Update...
The primary change to the Day 1 20Z Convective Outlook update was to
make minor eastward expansions of wind probabilities into eastern
IA, as some of the latest convection allowing guidance depicts an
MCS persisting into this region. Otherwise, the previous forecast
(see below) remains on track, with very small adjustments made to
thunder/severe probabilities to account for observational trends
and/or guidance consensus updates.

..Squitieri.. 07/18/2025

.PREV DISCUSSION... /ISSUED 1106 AM CDT Fri Jul 18 2025/

...Virginia/North Carolina to the Mid-South...
Late morning surface analysis places a stationary front draped from
west to east from the mid MS Valley eastward into the Mid-Atlantic
states. Visible satellite/radar mosaic imagery shows a couple of
weak MCVs moving east over the northern VA/MD vicinity and over far
eastern KY. The latter disturbance will probably prove instrumental
in aiding storm development across VA into northern NC this
afternoon.

South of the front, rich low-level moisture and heating will act to
offset weak mid-level lapse rates and yield moderate to strong
buoyancy from southeast MO eastward to the Mid-Atlantic coast.
Early indications of a swelling cumulus field over the WV/VA
mountains will gradually evolve into a cluster of storms as
convective inhibition continues to erode through early afternoon.
Other clusters of storms will develop and move west to east given
marginal deep-layer mean westerly flow. Although small hail
0.50-1.00 inch in diameter is possible with the strongest cores, the
primary hazard with the stronger storms will be damaging gusts
(50-65 mph) with the more intense water-loaded downdrafts. This
activity will likely diminish by the early to mid evening.

...South Dakota/Nebraska into Minnesota/Iowa...
Gradual low-level moistening is forecast through this evening ahead
of a weak front forecast to be in place over the eastern Dakotas
into western NE. An initially appreciable capping inversion will
inhibit surface-based storm development until heating gradually
weakens inhibition by late afternoon. A very unstable airmass is
forecast by late afternoon/early evening, but nebulous forcing lends
uncertainty in terms of storm development/timing. Models suggest
storms will primarily develop this evening associated with
strengthening low-level theta-e advection. Supercells are possible
early in the convective life cycle with a risk for all hazards,
including the possibility for a couple of tornadoes, but large hail
may be the main hazard. Upscale growth into a cluster or MCS is
possible near the terminus of a southwesterly 850-mb LLJ with severe
gusts the becoming the primary threat. Models vary considerably
whether storm intensity is maintained through much of the overnight
and beyond the Day-1 period, or if a gradual diminishing in severe
occurs.

...Great Basin into Wyoming and Far Southern Montana...
Initially high-based convection should develop this afternoon across
parts of the Great Basin into WY as modest ascent associated with a
weak/low-amplitude mid-level impulse spreads eastward across these
areas. Steep low/mid-level lapse rates and a deep, very well-mixed
boundary layer should support isolated severe gusts with the
stronger thunderstorms. Somewhat greater low-level moisture should
be present this afternoon across parts of southern MT into
northern/eastern WY, generally along/east of the Bighorn/Laramie
Mountains. Isolated severe hail may occur with marginal supercells
given greater instability/shear forecast across these areas.

$$

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

607
FLUS43 KLOT 182013
HWOLOT

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
313 PM CDT Fri Jul 18 2025

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-192015-
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-
313 PM CDT Fri Jul 18 2025 /413 PM EDT Fri Jul 18 2025/

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

.DAY ONE...Tonight.

Weather hazards expected...

Limited Thunderstorm Risk Late Tonight.

DISCUSSION...

A line of decaying thunderstorms may bring gusty winds to
northern Illinois west of the Chicago metro toward sunrise
Saturday morning.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Saturday...
Elevated Thunderstorm Risk...with an associated:
Level 2 of 5 Severe Thunderstorm Risk.
Elevated Flooding Risk.
Sunday...
Limited Thunderstorm Risk...with an associated:
Level 1 of 5 Severe Thunderstorm Risk south of I-80.
Elevated Flooding Risk south of Dixon to Watseka line.
Monday...
Limited Flooding Risk.
Limited Thunderstorm Risk.
Tuesday...
Limited Flooding Risk.
Limited Thunderstorm Risk.
Limited Excessive Heat Risk.
Wednesday and Thursday...
Limited Thunderstorm Risk.
Elevated Excessive Heat Risk.

DISCUSSION...

Several rounds of thunderstorms may occur through early next
week with strong to severe thunderstorms possible along with
torrential rain and localized flash flooding. The greatest
chances will remain south of I-80.

Dangerous heat and humidity is possible the middle of next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be necessary through tonight.

GENERAL STORM MOTION OF THE DAY:

Moving toward the southeast at 30 mph.

$$

LMZ740>745-192015-
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-
313 PM CDT Fri Jul 18 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...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Saturday...
Limited Thunderstorm Risk...with an associated:
Level 2 of 5 Severe Thunderstorm Risk.
Sunday...
Limited Thunderstorm Risk.
Tuesday through Thursday...
Limited Thunderstorm Risk.

$$

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

650
ACUS02 KWNS 181729
SWODY2
SPC AC 181727

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1227 PM CDT Fri Jul 18 2025

Valid 191200Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM IOWA EASTWARD
TOWARD OHIO...AND OVER THE CENTRAL HIGH PLAINS...

...SUMMARY...
Scattered severe storms are possible over parts of the Midwest, and
over the central High Plains. Areas of damaging winds and hail will
be possible.

...Midwest...
A conditional and complex severe risk is forecast, beginning
Saturday morning over eastern IA and vicinity. Here, models indicate
an MCS will likely be ongoing, but whether this system persists
across IL and IN during day is uncertain. Most likely, this system
will weaken, which will allow daytime destabilization across the
area. However, redevelopment is also uncertain during the day across
southern WI/IL/IN, and may depend on mesoscale boundaries from
earlier storms. In any event, a moist and unstable air mass will
develop, and conditionally favor severe storms. This will exist
beneath moderate west to northwest flow aloft, and deep-layer shear
may even favor supercells. Any supercells that can develop during
the afternoon or early evening will be capable of large hail,
perhaps a tornado, and damaging gusts. Additional storms are likely
overnight in the warm advection regime from southern IA/northern MO
into western IL.

Farther east and late, west/southwest flow around 850 mb will aid
lift and destabilization with clusters of storms possible from OH
into western PA and NY. Scattered damaging gusts appear to be the
main concern.

...Central High Plains...
High pressure over the northern Plains will maintain moist easterly
surface winds near a stalled front near the KS/NE border, with
moderate instability developing as far west as southeast WY and
northeast CO. Afternoon storms will likely form in this uncapped air
mass over the High Plains, with a few supercells producing large
hail expected. Capping will be a concern farther east, but eventual
outflow production may allow an MCS to develop with damaging winds
spreading into parts of northwest KS and southwest NE.

..Jewell.. 07/18/2025

$$

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

786
ACUS03 KWNS 181919
SWODY3
SPC AC 181919

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0219 PM CDT Fri Jul 18 2025

Valid 201200Z - 211200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE MID
ATLANTIC WESTWARD ACROSS OHIO VALLEY AND INTO THE NORTHERN PLAINS...

...SUMMARY...
Scattered strong storms with at least isolated severe potential will
be possible from the Mid Atlantic into Ohio and Missouri Valleys and
central Plains Sunday into Sunday night.

...Synopsis...
A large area of cyclonic flow aloft will exist over the Northeast as
an upper low moves southeastward across Quebec. To the south, and
upper high will be centered over the Gulf Coast states, with an
enhanced belt of midlevel westerlies across the Midwest.

At the surface, a cold front will push southeastward across New
England and toward the Mid Atlantic by late afternoon, with the
western extension of this same boundary stalling into the Mid MO
Valley.

A very moist air mass will exist ahead of the main front, aiding
episodes of strong storms from southern New England/Mid Atlantic
Coast area, the OH Valley, and from SD into NE.

...Mid Atlantic/Northeast...
Scattered thunderstorms are likely in association with the cold
front beginning relatively early in the day. The air mass will be
very moist, and heating will result in up to 1500 J/kg MUCAPE prior
to the front moving offshore late in the day. Forecast soundings
indicate poor lapse rates aloft, but strong gusts may occur with
fast moving clusters of storms as far south as NJ.

...Central to northern Plains...
A surface trough will deepen from eastern MT into western SD/NE/KS,
with strong heating. Southeast surface winds will maintain moisture
into the Dakotas and NE, with locally strong instability developing
within a narrow uncapped zone. A few storms capable of large hail
and localized wind damage may occur from late afternoon into early
evening. Storm motions should remain relatively slow and severe
threat localized as shear will remain marginal this far south. A
small Slight Risk could be needed in later outlooks as precision
increases.

...OH Valley...
Early day storms near/north of the elongated front may linger across
parts of IL/IN/OH, with a diurnal uptick as heating occurs from near
St. Louis eastward across KY and into western VA. Poor lapse rates
aloft and modest westerlies aloft suggest only localized severe
potential within the broader thunderstorm area, with a few damaging
downbursts possible.

..Jewell.. 07/18/2025

$$

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.