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Current Conditions

A message from COD Meteorology

Current Local Radar

Temperature
82°F
Feels Like:
82°F
Dew Point	Humidity
52°F	35%

Mostly Cloudy

Wind Strength
Light	Moderate	Strong
East-northeast at 5 mph

Local Graphical Forecast (Updated: 08/11/20 4:16 pm)

Tuesday (8/11)
Day	Night


High	Low
	63

Wednesday (8/12)
Day	Night


High	Low
86	67

Thursday (8/13)
Day	Night


High	Low
88	67

Friday (8/14)
Day	Night

20%	20%
High	Low
87	69

Saturday (8/15)
Day	Night


High	Low
88	69

Sunday (8/16)
Day	Night


High	Low
86	65

Monday (8/17)
Day	Night


High	Low
80	61

Detailed Text Forecast (Updated: 08/11/20 4:16 pm)

Tuesday Night: Mostly clear, with a low around 63. East northeast wind around 5 mph becoming calm in the evening.

Wednesday: Sunny, with a high near 86. Calm wind becoming east around 5 mph in the afternoon. Winds could gust as high as 10 mph.

Wednesday Night: Mostly clear, with a low around 67. East wind around 5 mph becoming calm in the evening. Winds could gust as high as 10 mph.

Thursday: Sunny, with a high near 88. Light east northeast wind becoming east 5 to 10 mph in the morning. Winds could gust as high as 15 mph.

Thursday Night: Partly cloudy, with a low around 67. East wind 5 to 10 mph.

Friday: A 20 percent chance of showers and thunderstorms after 8am. Mostly sunny, with a high near 87.

Friday Night: A 20 percent chance of showers and thunderstorms before 2am. Partly cloudy, with a low around 69.

Saturday: A slight chance of showers and thunderstorms after 8am. Mostly sunny, with a high near 88.

Saturday Night: A chance of showers and thunderstorms, mainly between 8pm and 2am. Partly cloudy, with a low around 69.

Sunday: A chance of showers and thunderstorms, mainly after 2pm. Mostly sunny, with a high near 86.

Sunday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 65.

Monday: Mostly sunny, with a high near 80.

Monday Night: Partly cloudy, with a low around 61.

Tuesday: Sunny, with a high near 75.

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SPC Convective Outlook Day 1

See Product Description

116
ACUS01 KWNS 111959
SWODY1
SPC AC 111957

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Tue Aug 11 2020

Valid 112000Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
SOUTH DAKOTA AND WESTERN NEBRASKA...

...SUMMARY...
The most likely area for severe wind and hail during the late
afternoon into tonight is across western Nebraska into South Dakota.

Little change was made to the previous outlook except for minor
thunder line changes over southeast Texas and parts of the West.

..Jewell.. 08/11/2020

.PREV DISCUSSION... /ISSUED 1119 AM CDT Tue Aug 11 2020/

...SD/NE...
Low-level warm advection in conjunction with a leading mid-level
impulse has sustained general thunder across central SD this
morning. This activity should decay this afternoon as warm advection
wanes.

Late-afternoon storm development should focus where convergence is
maximized along the lee trough/dryline in the NE Panhandle vicinity.
This region will lie in the gradient between moderate mid-level
westerlies across northern WY and SD, and weaker flow across CO and
KS. The setup should favor a few multicells and a couple transient
supercells with some risk for severe hail/wind.

An upstream mid-level impulse along the MT/WY border will track into
northern SD this evening. Most guidance delays convective
development until after sunset when the low-level jet intensifies
from western KS into SD. The CAPE/shear combination in SD will be
greater relative to farther south, suggesting that an organized
cluster with severe wind/hail could form in the late evening to
overnight. Have expanded cat 2/SLGT risk east to account for this
scenario.

...Central/southern High Plains...
Isolated late-afternoon to early-evening thunderstorms are expected
along the lee trough/dryline from the CO/KS border south to west TX.
While 500-mb westerlies should hold from 15-25 kts, a belt of 50-60
kt 250-mb flow should be maintained across southern CO into the
adjacent High Plains. This will aid in isolated severe hail/wind.

...AR and eastern OK...
An MCV near the northeast OK/southeast KS border should drift
east-southeast towards AR. Regenerative convection is anticipated
through much of the period near/east/south of the MCV. Modest
enhancement to mid-level flow on the southwest flank of the MCV
across OK may aid in loosely organized multicell clusters during the
late afternoon and early evening from the Lower Red River Valley
into AR. Isolated damaging wind gusts should be the main hazard, but
marginal hail will also be possible.

...Eastern NY to western/northern New England...
A decaying shortwave trough across southeast Ontario and southwest
Quebec may support isolated thunderstorms from eastern NY to
northern ME during the late afternoon and early evening along a
trailing cold front. Convergence along the front should be weak, and
confidence in convective initiation/longevity is not particularly
high. Nevertheless, storms that can develop will pose a risk of
locally damaging wind gusts.

$$

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 2

See Product Description

534
ACUS02 KWNS 111732
SWODY2
SPC AC 111731

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1231 PM CDT Tue Aug 11 2020

Valid 121200Z - 131200Z

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

...SUMMARY...
Severe thunderstorms with large hail and a few strong gusts are
possible across parts of far eastern Montana into North Dakota
Wednesday afternoon and evening, and over parts of Nebraska and
northern Kansas.

...Synopsis...
An upper high will remain situated over NM while an upper trough
moves east across the Pacific Northwest and northern Rockies. Height
falls will occur late in the day over MT and ND, with surface
trough/wind shift over eastern MT at 00Z. East of this boundary,
southeast surface winds will bring 60s F dewpoints northwestward,
aiding destabilization. The combination of lengthening hodographs
and lift should result in at least a few severe storms.

To the south, a lee trough will extend south along the length of the
high Plains, with a moist, unstable air mass along and east.
Temperatures aloft will remain relatively cool across the central
Plains, aiding lapse rates and instability.

Elsewhere, an early disturbance associated with early day storms
will move across parts of MN, where low-level warm advection will
persist near a warm front. This may aid re-development during the
afternoon or evening, with a few strong storms possible there.

...Eastern MT into ND...
Storms will develop along the cold front over far eastern MT and
move into western ND during the early evening. Veering winds with
height will favor supercells capable of large hail, though
temperature/dewpoint spreads and only modest SRH level should
minimize tornado potential. Capping will limit eastward extent
during the evening, but an isolated cell may potentially affect
central ND.

...Central Plains...
Strong heating will lead to a deep, mixed layer over WY, CO,
southwest KS and into the OK/TX Panhandles. High-based storms are
expected to form during the afternoon over far eastern CO and
western NE near the surface trough. Marginal hail is possible
initially with a developing wind threat as outflow increases in
coverage. An increasing low-level jet late in the day and overnight
will maintain good theta-e advection ahead of any developing storms,
suggesting MCS potential into the evening to the east/southeast over
central NE and into KS.

..Jewell.. 08/11/2020

$$

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

815
ACUS03 KWNS 110717
SWODY3
SPC AC 110716

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 AM CDT Tue Aug 11 2020

Valid 131200Z - 141200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS...

...SUMMARY...
Severe thunderstorms with isolated large hail and wind damage will
be possible in parts of the northern Plains Thursday afternoon and
evening. Marginally severe thunderstorms will be possible from parts
of the central Plains and lower Missouri Valley northward into the
the lower to mid Missouri Valley.

...Northern Plains...
An upper-level trough is forecast to move eastward across the
northwestern United States on Thursday as southwest mid-level flow
is maintained in the northern Plains. At the surface, a cold front
is forecast to move eastward across the northern Plains with a moist
airmass located ahead of the front from eastern Nebraska northward
into the eastern Dakotas. Surface dewpoints from the mid 60s to
lower 70s F will likely result in moderate to strong instability by
afternoon. Although a cap should suppress convective development
during the day, thunderstorms appear likely to form along and just
ahead of the front during the late afternoon and early evening as
the cap weakens. Model forecasts suggest that a line of
thunderstorms will organize during the early evening and move across
eastern North Dakota and northeastern South Dakota.

NAM and GFS Forecast soundings in eastern North Dakota at 21Z on
Thursday show MLCAPE in the 2000 to 3000 J/kg range and have 0-6 km
shear of 30 to 35 kt. This combined with mid-level lapse rates near
8.5 C/km would support a severe threat. Supercells with isolated
large hail would be possible with discrete cells that form ahead of
the front near any instability maximum. A potential for wind damage
would be most likely with line segments that organize along the
front. The severe threat should continue into the early and mid
evening, eventually affecting parts of northwest Minnesota.

One problem with the forecast is that the models are not in
agreement concerning convective coverage. Of the NAM, GFS and ECMWF,
the ECMWF is the most aggressive solution concerning this issue.
This solution suggests that MCS development will be possible across
parts of the northern Plains by Thursday evening. Due to this
possibility, a slight risk area has been introduced.

...Central Plains/Lower to Mid Missouri Valley...
A slow-moving upper-level ridge is forecast to be located in the
central Plains on Thursday. Beneath the ridge, a very moist airmass
will result in moderate to strong destabilization by afternoon.
Although a cap is forecast across the instability corridor, isolated
thunderstorms may be able to overcome the cap during the late
afternoon and early evening. Any cells that can become rooted in the
stronger instability could produced marginally severe wind gusts and
hail, mainly due to the steep lapse rates in place.

..Broyles.. 08/11/2020

$$

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.