SPC MD 245

MD 0245 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PORTIONS OF NORTHEAST KANSAS…NORTHWEST MISSOURI…AND FAR SOUTHEAST NEBRASKA

MD 0245 Image


Mesoscale Discussion 0245
NWS Storm Prediction Center Norman OK
0955 AM CDT Thu Mar 28 2019

Areas affected...Portions of northeast Kansas...northwest
Missouri...and far southeast Nebraska

Concerning...Severe potential...Watch possible 

Valid 281455Z - 281700Z

Probability of Watch Issuance...40 percent

SUMMARY...Thunderstorms, some of which have produced marginally
severe hail, will continue to evolve through the area in the next
few hours, with the threat for severe hail continuing.  A Severe
Thunderstorm Watch is possible.

DISCUSSION...Two separate areas of elevated thunderstorms are
approaching the area, one from the west that is beginning to show
some upscale growth over the Nebraska/Kansas border and another
cluster of left-moving cells with some supercell characteristics
approaching the area from the south.  The elevated CAPE of 500-1250
J/kg and a mid-level-lapse rate plume of 7-8 C/km that has supported
this convection stretches east ahead of the current storms.  This
suggests the intensity of these storms will be maintained in the
next few hours.  

HRRR guidance suggests some continuation of upscale growth seen in
recent radar imagery in the northern cluster.  This decrease in
discrete modes suggests some downward trend in severe hail threat
with the northern cluster, and a lack of surface heating underneath
the extensive anvils and the deep surface stable layer should
continue to limit the severe wind threat.  However, HRRR guidance
has not depicted well the left-moving cluster of cells/supercells
approaching the Topeka area, and the threat for marginally severe
hail should continue with this cluster as more discrete/cellular
modes are expected to continue.  Although the coverage and intensity
of the threat is rather limited, a Severe Thunderstorm Watch may be
needed if trends persist given the marginal severe hail threat.

..Coniglio/Hart.. 03/28/2019

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...EAX...OAX...TOP...ICT...GID...

LAT...LON   40789633 40509487 39949361 39059341 38339412 38259534
            38399687 39389769 40369744 40789633 

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SPC MD 244

MD 0244 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PARTS OF SOUTHERN NEBRASKA AND NORTHERN KANSAS

MD 0244 Image


Mesoscale Discussion 0244
NWS Storm Prediction Center Norman OK
0752 AM CDT Thu Mar 28 2019

Areas affected...Parts of southern Nebraska and northern Kansas

Concerning...Severe potential...Watch unlikely 

Valid 281252Z - 281445Z

Probability of Watch Issuance...5 percent

SUMMARY...Thunderstorms, some strong, are expected to increase while
spreading across the region through midday, accompanied by at least
some risk for severe hail.

DISCUSSION...A focused area of strengthening large-scale upward
vertical motion, supported by lower/mid tropospheric warm advection,
has contributed to the initiation of vigorous ongoing thunderstorm
development near the central Kansas/Nebraska border area.  Model
output suggests that this likely will persist and increase,
gradually spreading eastward and southeastward across the state
border area through midday.

Although moisture content remains somewhat modest across this
region, fairly steep mid-level lapse rates associated with elevated
mixed-layer air appear to be contributing to most unstable CAPE on
the order of 1000-2000 J/kg.  Furthermore, vertical shear through
the convective layer appears moderate to strong, though winds in the
inflow layer may be modest to weak. 

Given this regime, vigorous thunderstorm activity appears likely to
persist, and gradually organize, with stronger embedded cells
perhaps occasionally becoming capable of producing marginally severe
hail.  With convection based above a substantive stable layer from
the surface through around 850 mb, the potential for damaging wind
gusts appears low through at least early afternoon.

..Kerr/Edwards.. 03/28/2019

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...OAX...TOP...ICT...GID...GLD...

LAT...LON   40559916 40649705 40359606 39029621 38919715 39089823
            39879985 40559916 

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SPC MD 228

MD 0228 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR NORTH-CENTRAL KANSAS AND SOUTH-CENTRAL NEBRASKA

MD 0228 Image


Mesoscale Discussion 0228
NWS Storm Prediction Center Norman OK
0256 PM CDT Sat Mar 23 2019

Areas affected...north-central Kansas and south-central Nebraska

Concerning...Severe potential...Watch unlikely 

Valid 231956Z - 232200Z

Probability of Watch Issuance...5 percent

SUMMARY...Thunderstorms are expected to develop this afternoon
within a low-level-directional-sheared environment. Although
instability will remain limited, small hail and a brief tornado or
two may be possible.

DISCUSSION...A strong surface low will move east-northeast, across
northwest Kansas, this afternoon and evening. Although instability
is limited along and ahead of this surface low, strong large-scale
ascent, steep midlevel-lapse rates, and little-if-any convective
inhibition will promote the development of isolated thunderstorms
this afternoon and early evening. The large-scale wind field is
relatively weak across the area, but does exhibit strong low-level
direction shear. Thus, even though thunderstorm updrafts may not be
capable of sustained mid-level rotation, shallow, transient
mesocyclones will be possible with any discrete thunderstorm.
Additionally, cold midlevel temperatures will also support the
potential for small hail/graupel with any sustained updraft. The
threat should quickly end with the loss of diurnal heating. A watch
is currently not expected.

..Marsh/Hart.. 03/23/2019

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...OAX...TOP...ICT...GID...DDC...GLD...

LAT...LON   38709927 39649985 40589701 39479656 37959697 38709927 

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