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This is our main severe weather forecast product or "convective outlook", for the coverage region for today. This product is routinely updated several times during the period so that you can keep current on the latest severe weather information. If a significant severe weather outbreak is forecast, such information will be highlighted in the appropriate section of this product.

THE OUTLOOK DETAILS AT A GLANCE

Categorical
NO SEVERE STORMS
LIMITED
SLIGHT
ELEVATED
MODERATE
HIGH
Thunderstorm Mode
None
Sub-Severe
QLCS - Quasi-Linear Convective System
Multicell - Clusters/lines
Supercell
Storms in progress
Thunderstorm Timing
None
After 9:00 am
After 1:00 pm
After 4:00 pm
After 7:00 pm
Storms In Progress
Probabilities
Tornadoes (F0-F2)
Large Diameter Hail
Damaging Winds

Violent Tornadoes (F3-F5)


Very Large Hail (2"+)

Derecho Event

Thunderstorm Coverage

No coverage
Isolated
Widely Scattered
Scattered
Scattered to numerous
Widespread

1600 UTC DAY 1 SEVERE WEATHER OUTLOOK GRAPHICS

Categorical Tornado Winds Large Hail
 Population  Cities/Towns  CWAs  Interstates  Counties



RACDY1

DAY 1 CONVECTIVE OUTLOOK  
SCO/MIDWEST WEATHER SERVICE STEVENS POINT/WHITING WI
220 PM CDT WED JUN 20 2018
 
SEVERE THUNDERSTORM FORECAST DISCUSSION...
SUMMARY OF THE 2000 UTC...300 PM...INFORMATION.

REGIONAL HIGHLIGHTS...

Scattered thunderstorms are expected this afternoon and evening across much of the coverage region, with the greatest concentration of storms
across Iowa, Illinois, and Minnesota. Other more scattered storms are possible across Wisconsin and upper Michigan.   

CATEGORICAL RISK HEADLINES...

 THERE IS A LIMITED RISK FOR SEVERE THUNDERSTORMS ACROSS MAINLY PARTS OF CENTRAL IA.

SYNOPTIC SUMMARY AND DISCUSSION...

Split flow pattern aloft continues, with the northern stream arching around a large stout mid level ridge axis across much of Canada. The southern
stream runs from CA across the central plains into the mid Atlantic coast. Meanwhile, a rather strong closed now cut-off low will continue digging
southeast across the western Dakotas toward the central plains. At the surface, a wavy quasi-stationary boundary was draped from a low over
western IA into OH. South of this boundary, a very warm, humid, and unstable environment was in place. Scattered thunderstorms are developing
now across much of IA in response to the approaching upper low and surface features interacting with the instability and shear, albeit weak.
Continued strong surface heating should help enhance instability, and coupled with around 25 knots of effective shear, should help foster more
thunderstorms into late afternoon and evening. Multicell clusters with a large hail and damaging wind potential. A few brief tornado spinups are
also possible, mainly early in storm development.

SIGNIFICANT WEATHER CONCERN AREAS:

None.

THE NEXT UPDATE:

The next forecast update is scheduled for 800 PM.

FORECASTER: Zimmerman

NNN

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