SPC MD 299

MD 0299 CONCERNING SEVERE POTENTIAL…WATCH LIKELY FOR NORTH-CENTRAL KANSAS INTO SOUTHEAST NEBRASKA

MD 0299 Image


Mesoscale Discussion 0299
NWS Storm Prediction Center Norman OK
0549 PM CDT Wed Apr 10 2019

Areas affected...North-central Kansas into southeast Nebraska

Concerning...Severe potential...Watch likely 

Valid 102249Z - 110045Z

Probability of Watch Issuance...80 percent

SUMMARY...A few severe storms capable of mainly damaging hail may
develop after 00Z.

DISCUSSION...A surface low continues to deepen across central KS,
and will track northeastward into southeast NE this evening. The
synoptic setup overall is quite favorable for severe storms with
steep lapse rates aloft, strong wind profiles, and lift. However,
moisture is a major concern. GPS PW sensors indicate values
approaching 0.60" near Wichita, but a band of relatively greater PW
does exist near the stationary/developing warm front from near
Kansas City into southeast NE.

Recent visible imagery and radar shows skeletal convection forming
near Russell KS as of 23Z, ahead of the low. The zone from here
northeastward appears to have the greatest chance of severe storms
capable of large hail. Supercells are possible, either elevated, or,
surface based right along the front, with an enhanced risk of
damaging hail. While low-level moisture is a concern, a conditional
tornado risk still exists given favorable storm mode, steep lapse
rates, lift along the boundary, and increasing low-level SRH.

..Jewell/Guyer.. 04/10/2019

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

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

LAT...LON   39549925 40579892 41179839 41459749 41549664 41429611
            41179581 40779564 40369561 40119570 39989596 39889631
            39789661 39589706 39269752 38859810 38749852 38799876
            39079914 39549925 

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SPC MD 273

MD 0273 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR FAR SOUTH-CENTRAL NEBRASKA INTO NORTH-CENTRAL KS

MD 0273 Image


Mesoscale Discussion 0273
NWS Storm Prediction Center Norman OK
0143 AM CDT Sun Apr 07 2019

Areas affected...far south-central Nebraska into north-central KS

Concerning...Severe potential...Watch unlikely 

Valid 070643Z - 070745Z

Probability of Watch Issuance...5 percent

SUMMARY...Isolated hail near 1 inch in diameter will be possible the
next 1-2 hours as storms track southeast from south-central Nebraska
into north-central KS.

DISCUSSION...Elevated thunderstorms may continue to pose a
marginally severe hail threat the next 1-2 hours as they track
southeast from far south-central NE into north-central KS. These
storms were occurring in an area of weak forcing associated with the
northern stream shortwave trough moving across the central Plains
and in the vicinity of a surface trough. Steep midlevel lapse rates
around 7-8 C/km per 00z regional RAOBs and weak elevated instability
will continue to support some stronger updrafts over the next couple
of hours. As the storms track further southeast, they may encounter
some subsidence on the back side of a MCV currently over far
southeast NE/northwest MO/southwest IA. The impact of this
subsidence is evident in surface dewpoints falling into the mid 40s
across central KS the last couple of hours. Given the localized
nature of the threat, and that storms are expected to weaken in the
next couple of hours, a watch is not expected.

..Leitman/Thompson.. 04/07/2019

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

ATTN...WFO...TOP...ICT...GID...

LAT...LON   40429894 40309844 39959763 39549742 39249742 39099766
            39139833 39419882 39759907 40179923 40429894 

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SPC MD 267

MD 0267 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF CENTRAL/EASTERN KS

MD 0267 Image


Mesoscale Discussion 0267
NWS Storm Prediction Center Norman OK
0330 PM CDT Sat Apr 06 2019

Areas affected...Portions of central/eastern KS

Concerning...Severe potential...Watch unlikely 

Valid 062030Z - 062300Z

Probability of Watch Issuance...20 percent

SUMMARY...Marginally severe hail may occur this afternoon into the
early evening. Watch issuance is unlikely.

DISCUSSION...Thunderstorms have developed this afternoon ahead of a
shortwave trough across parts of central KS. Cloud cover has
generally been more prevalent across this area compared to locations
farther south, and instability should generally remain weak through
the evening. Although low to mid-level winds are more southerly per
KICT and KTOP VWPs, some speed shear is present in RAP forecast
soundings across parts of central/eastern KS. Related 30-35 kt of
effective bulk shear may be enough to support occasional updraft
organization, and marginally severe hail could occur as mid-level
lapse rates modestly steepen with the approach of the shortwave
trough. The overall severe threat will likely remain too isolated
and marginal to warrant watch issuance.

..Gleason/Hart.. 04/06/2019

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

ATTN...WFO...SGF...EAX...TOP...ICT...

LAT...LON   37029806 37409834 38429838 39239783 39369645 39019546
            38039502 37479518 37069561 37029806 

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SPC MD 261

MD 0261 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR TX SOUTH PLAINS VICINITY

MD 0261 Image


Mesoscale Discussion 0261
NWS Storm Prediction Center Norman OK
0141 AM CDT Sat Apr 06 2019

Areas affected...TX South Plains vicinity

Concerning...Severe potential...Watch unlikely 

Valid 060641Z - 060815Z

Probability of Watch Issuance...20 percent

SUMMARY...Storms may briefly intensify at times through early
morning, possibly producing marginally severe hail and strong wind
gusts. A watch is not anticipated at this time.

DISCUSSION...Isolated strong to briefly severe stroms will continue
the next several hours across the TX South Plains/western north TX
vicinity. Current cells/bowing segments affecting Kent, Stonewall
and King counties in TX have shown periodic intensification over the
last hour or so. Brief pulses in MRMS MESH data suggesting hail size
up to around 1-1.5 inches possible, though most recent trends have
decreased. Furthermore, velocity data from KLBB has shown moderate
midlevel rotation at times, further supporting hail potential, and
possibly a strong to severe gust where  boundary layer inhibition
may be weak and/or downdrafts briefly intense. 

This band of strong convection was occurring ahead of a shortwave
impulse ejecting across southwest TX currently and on the nose of
stronger southeasterly return flow. Surface dewpoints are maximized
in this location, though still in the mid 50s to near 60F. Storms
have been ongoing for several hours and IR satellite indicates a
maturing MCS over northwest TX with a large area of cold cloud tops
over the eastern portions of the South Plains. Expect that hail
concerns should continue to be marginal heading into the early
morning hours as this system tracks east/northeast toward southwest
OK and north TX. For this reason, a watch is not expected though
brief periods of intensification are possible.

Additional isolated convection is developing further to the
west/southwest in the vicinity of the surface dryline near the
higher terrain of southwest TX. This convection is expected to
remain isolated, though could produce some hail as midlevel lapse
rates remain intact across this area.

..Leitman/Thompson.. 04/06/2019

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

ATTN...WFO...OUN...SJT...LUB...MAF...

LAT...LON   33739914 34219923 34559945 34689986 34600035 34280080
            33900096 33120181 32510284 32020294 31770291 30690287
            30470243 30520196 31280107 33739914 

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SPC MD 248

MD 0248 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PARTS OF OK INTO FAR SOUTHEASTERN KS…SOUTHWESTERN MO…AND NORTHWESTERN AR

MD 0248 Image


Mesoscale Discussion 0248
NWS Storm Prediction Center Norman OK
1130 PM CDT Fri Mar 29 2019

Areas affected...Parts of OK into far southeastern KS...southwestern
MO...and northwestern AR

Concerning...Severe potential...Watch possible 

Valid 300430Z - 300700Z

Probability of Watch Issuance...40 percent

SUMMARY...Isolated large hail may occur overnight as thunderstorms
increase in coverage and intensity. While not immediately likely,
severe thunderstorm watch issuance may be needed by 1-2 AM CDT.

DISCUSSION...04Z surface analysis shows a 1008 mb low centered along
the KS/MO border near Pittsburg, KS. A cold front extends
southwestward from this low across central/western OK into the TX
Panhandle, while a warm front is located over parts of southwestern
MO. A shortwave trough over the central High Plains will shift
eastward overnight. At least scattered thunderstorms appear likely
to develop by 06-07Z (1-2 AM CDT) as large-scale ascent associated
with the shortwave trough overspreads much of OK and vicinity.

Initial convective development appears to be underway across the
eastern TX Panhandle and northwestern OK at 0420Z with cooling of
cloud tops noted on infrared satellite imagery. These thunderstorms
will likely remain elevated above a stable near-surface layer as
they move eastward across OK and eventually southwestern
MO/northwestern AR overnight. Steep mid-level lapse rates of 7.5 to
8.5 C/km present on 00Z area soundings are supporting MUCAPE of
1000-2000 J/kg across much of OK. Around 40-50 kt of effective bulk
shear in the cloud-bearing layer should initially support supercells
with an isolated large hail threat.

Convective mode becomes less clear with eastward extent across OK,
as storms may have a tendency to organize into one or more line
segments as they interact with the cold front. Gusty winds may also
occur, but downdrafts will probably struggle to reach the surface
given the strong low-level inversion. Convective trends will be
monitored over the next several hours for possible watch issuance.

..Gleason/Guyer.. 03/30/2019

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

ATTN...WFO...SGF...TSA...ICT...OUN...

LAT...LON   34629951 34859985 35279994 36949645 37189543 37469415
            37279334 36479335 36079357 35459445 35099541 34889619
            34699701 34559808 34509881 34629951 

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SPC MD 246

MD 0246 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR CENTRAL/NORTHEASTERN OKLAHOMA…SOUTHEASTERN KANSAS…SOUTHWESTERN MISSOURI…AND FAR NORTHWEST ARKANSAS

MD 0246 Image


Mesoscale Discussion 0246
NWS Storm Prediction Center Norman OK
0839 AM CDT Fri Mar 29 2019

Areas affected...Central/northeastern Oklahoma...southeastern
Kansas...southwestern Missouri...and far northwest Arkansas

Concerning...Severe potential...Watch unlikely 

Valid 291339Z - 291515Z

Probability of Watch Issuance...20 percent

SUMMARY...Occasional instances of 1+ inch hailstones are possible
with stronger thunderstorms over the next couple of hours.  A WW
issuance is not anticipated at this time.

DISCUSSION...Elevated convection persists along an axis from near
CQB to near TUL and BVO - and is more widespread than operational
models depict.  Though forcing for ascent aloft is negligible,
mid-level instability (8.5-9 deg C/km) noted on 12Z soundings and
subtle speed convergence at the base of this unstable layer (800-850
mb) is likely forcing ongoing convection along the eastern edge of
the strongest lapse rates.  Though effective shear is marginal, the
magnitude of lapse rates will continue to support a hail risk with
the strongest storms, with 1" or greater hail stones possible for
the next couple of hours.

Over time, flow at 800-850mb is expected to weaken and back to a
more south-southwesterly direction in response to cyclogenesis over
central Kansas.  This will likely lead to a weakening of ongoing
convection as convergence near the base of the lapse rate plume
weakens.  Thus, the isolated nature of the severe threat with
ongoing convection and expected weakening of this activity precludes
any need for a WW issuance.

..Cook.. 03/29/2019

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

ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN...

LAT...LON   37829623 38029570 38179474 38069404 37609369 36629375
            35849424 35359490 35119592 35029678 35069726 35279751
            35729736 36319710 36859705 37249691 37449670 37829623 

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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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SPC Mar 11, 2019 0730 UTC Day 3 Severe Thunderstorm Outlook

SPC 0730Z Day 3 Outlook

Day 3 Outlook Image

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0230 AM CDT Mon Mar 11 2019

Valid 131200Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL/EAST TX TO THE LOWER/MID MS VALLEY...

...SUMMARY...
Isolated strong to severe thunderstorms may occur from parts of
central/east Texas to the lower/mid Mississippi Valley on Wednesday.

...Synopsis...
A negatively tilted shortwave trough initially over the southern
High Plains should evolve into a closed upper low over the central
Plains and Upper Midwest on Wednesday. Continued northward low-level
moisture transport will occur across east TX into the lower/mid MS
Valley through the period as a northeastward-moving surface low
occludes in tandem with the upper trough/low.

...East TX into the Lower/Mid MS Valley...
A line of thunderstorms will likely be ongoing at the start of the
period across parts of central/east TX along a cold front extending
southward from the previously mentioned surface low. Even though a
moist low-level airmass should be in place ahead of this convection,
weak low/mid-level lapse rates should tend to limit instability
across most of the warm sector. Still, there appears to be potential
for some restrengthening of the line as it encounters a weakly
unstable airmass across east TX into LA and AR Wednesday afternoon.
Isolated strong to damaging winds will probably be the main threat
given the likely linear nature of the convection. An embedded QLCS
tornado cannot be ruled out either with strong low-level shear
forecast to be present across the warm sector. Due mainly to the
poor thermodynamic environment expected, the potential for a more
concentrated corridor of wind damage currently appears too
conditional/uncertain to include any more than a Marginal risk. The
northern extent of surface-based thunderstorm potential will likely
be constrained by the presence of lower to mid 60s surface dewpoints
across the mid MS Valley. Convection should spread eastward into
parts of MS and western TN Wednesday evening with a continued
marginal wind threat.

..Gleason.. 03/11/2019

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