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EXPERIMENTAL - DAY 1 CONVECTIVE OUTLOOK

Welcome to the "experimental day one convective outlook! We are considering giving this product a bit of a face lift to help not only enhance it, but to make it easier and user friendly for everyone. We have added a few new features, and are providing HD or "high Definition" graphics to the product. This should help bolster increased usefulness and accuracy of the chart graphics. Overall, this new experimental day one outlook should prove helpful and useful for our clients and other users. Notice: This product is on an experimental basis, so it may not always be current. In addition, some features may be disabled from time to time while we organize the page and content.
As always, if you have any questions, comments, or suggestions, please feel free to contact us via the web.


THE OUTLOOK DETAILS AT A GLANCE

The following section will pretty much remain as it appears on our current operational day 1 outlook. Some of the graphics have been enhanced.

Categorical Risk
No Risk Indicated
Sub-Severe Storms
Limited Risk
Slight Risk
Elevated Risk
Moderate Risk
High Risk

Convective Mode(s)
None
Linear (Squall Line)
Multicelluar
QLCS (Quasi-Linear Convective System)
Supercells
Mixed Mode(s)
Diurnally Driven Sub Severe Storms

Convective Initiation (Timing)
None
By or after 10 am
By or after 1 pm
By or after 4 pm
By or after 7 pm
Storms in Progress

Convective Coverage
None
Widely Isolated
Isolated
Widely Scattered
Scattered
Numerous
Widespread

Convective Probabilities
(Large Hail/Damaging Winds)
5 percent
15 percent
25 percent
40 percent
55 percent
60 percent or greater
None
Convective Probabilities
(Tornadoes)
2 Percent
6 Percent
12 Percent
20 Percent
35 Percent
50 Percent
None

FORECAST AT A GLANCE

The following "meters" will breakdown not only the categorical risks, but also show the forecast severe weather probabilities for each of the three primary elements (i.e. large diameter hail, damaging winds, and tornadoes). This should increase usefulness and promote a better understanding of those elements to be expected.

CATEGORICAL RISK
LARGE HAIL POTENTIAL
DAMAGING WIND POTENTIAL

1600 UTC DAY 1 SEVERE WEATHER OUTLOOK GRAPHICS

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




SCO RAC 49938

DAY 1 CONVECTIVE OUTLOOK {EXPERIMENTAL} 
SCO/MIDWEST WEATHER SERVICE STEVENS POINT/WHITING WI
236 PM CDT FRI MAY 25 2018

(Please note) This is an experimental product, and as such may not always be current. It is intended solely for evaluation purposes.
 
SUMMARY OF THE 1600 UTC...1100 AM CDT INFORMATION:

Summary...

Scattered thunderstorm are expected across a good part of the coverage region later this afternoon and tonight, with the greatest concentration
of storms along and ahead of both a warm front, then later a cold front crossing the area. A few storms, especially in parts of Iowa, Minnesota,
and Wisconsin could be severe. Some key locations which may be impacted include Waterloo and Mason City Iowa, Rochester and Mankato
Minnesota, and Eau Claire and Wausau Wisconsin. 

Synoptic Overview...

In mid/upper levels, a rather high amplitude, yet progressive, pattern will persist through the period.  From west to east:  a strong cyclone
its center now approaching the MRY-SFO area on the CA coast,  is forecast to progress inland through the period.  The 500mb low should be
located near RNO by 12Z, with trough south-southwestward off southern CA and west of northern Baja. Downstream, a ridge now located
over the Rockies (from AB to NM) and over Chihuahua will move eastward, extending from far west TX northward through the central and
northern High Plains by the end of the forecast period. A small, weak cyclone now over southern MB should move slowly eastward to
southeastward, devolving to an open wave trough near the MB/ON border overnight.  A few weak vorticity lobes, embedded within the
difluent flow south and southeast of the low, will cross the upper Mississippi Valley and parts of the Lake Superior/Lake Michigan regions.
Farther south, a shortwave trough and embedded, convectively enhanced vorticity max over eastern KS will move slowly eastward,
merging into a broader, north south swath of height weakness aloft that will connect with the strengthening deep layer disturbance over the
southern Gulf/Yucatan region.  Please refer to latest NHC outlooks for more information on this Gulf perturbation.

At the surface, 16Z analysis showed a trough and weak cold frontal zone from northwestern MN across central SD to western NE.  This boundary
should move eastward across MN today to parts of Lake Superior, WI and IA by the end of the forecast period. It is this boundary which will be
the focus for some robust convective development later this afternoon and evening.

Severe Thunderstorm Forecast Discussion...

* THERE IS A LIMITED RISK FOR SEVERE THUNDERSTORMS ACROSS -->

* THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS FROM -->

As with the southern Plains region, an ongoing, nonsevere clusters of thunderstorms is producing outflow that will leave a focusing boundary
behind.  The boundary should settle into south-central/southwestern WI and southern MN, with some northeastward retreat and cool side
diabatic destabilization possible by mid afternoon.  As such, some leeway will be left poleward of the boundary for sufficiently favorable
subsequent destabilization. Near and south of the boundary, and along/ahead of the fronts,  steep mid level lapse rates near the northeastern
rim of the EML, with some DCVA possible from one of the vorticity lobes pivoting through cyclonic flow aloft.  That should overlie a strongly
heated near surface air mass with 60s F dew points, fostering pre convective MLCAPE of 2000-3000 J/kg, locally/briefly higher.  Scattered
thunderstorms should develop this afternoon over western parts of the outlook areas, shifting southeastward while offering the risk of sporadic
large hail and damaging gusts.  Lack of more robust low level and deep shear suggest predominantly multicellular character, with some
organization into lines before encountering too much nocturnal stabilization and weakening this evening. 

...Maximum Risk By Hazard...
Tornadoes: 2%  -  Marginal
Damaging  Winds: 15%   -  Slight
Large Hail: 15%  -  Slight

Areas of widespread dangerous weather potential...

No areas forecast.

Next Update...

The next forecast update is scheduled for 1200 UTC Tuesday.

Forecaster: Brooks

All information and graphics © Copyright 2018 by Midwest Weather Service Storm Center, All rights reserved.