SPC MD 792

MD 0792 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR NORTHEAST KS

MD 0792 Image


Mesoscale Discussion 0792
NWS Storm Prediction Center Norman OK
0857 PM CDT Fri May 19 2017

Areas affected...Northeast KS

Concerning...Severe potential...Watch unlikely 

Valid 200157Z - 200300Z

Probability of Watch Issuance...20 percent

SUMMARY...Localized tornado threat may exist for the next hour or
so.

DISCUSSION...Recent radar imagery shows that a long-lived supercell
has become better organized as it enters an area of residual
low-level moisture near EMP. This slightly more favorable low-level
moisture and the resulting more moist inflow to the storm appears to
have supported an increase in intensity. Recent TWX VAD shows strong
veering within lowest 1 km with 0-1 km SRH over 400 m2/s2, which is
more than enough to support low-level rotation. Some localized
vorticity enhancement is also possible given the storms presence
within the warm frontal zone across the region. Given the limited
spatial extent of the better low-level moisture and continue
nocturnal stabilization, the longevity of the tornado threat with
this supercell is expected to be short-lived. Even so, a localized
tornado threat may exist for the next hour or so for this small
portion of east-central KS.

..Mosier/Hart.. 05/20/2017

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

ATTN...WFO...TOP...

LAT...LON   39039609 39209573 39159541 39009528 38709519 38519527
            38429550 38419603 38569623 39039609 

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SPC MD 789

MD 0789 CONCERNING TORNADO WATCH 250… FOR SOUTH-CENTRAL KS

MD 0789 Image


Mesoscale Discussion 0789
NWS Storm Prediction Center Norman OK
0645 PM CDT Fri May 19 2017

Areas affected...South-central KS

Concerning...Tornado Watch 250...

Valid 192345Z - 200045Z

The severe weather threat for Tornado Watch 250 continues.

SUMMARY...Some isolated damaging wind gusts and/or a brief tornado
are possible for the next hour or so but a gradually diminishing
threat is anticipated.

DISCUSSION...Recent KICT radar imagery suggests the cells within the
line moving across central KS have become more outflow-dominant.
This more outflow-dominant storm structure and continued linear
forcing for ascent provided by the cold front suggest persistence of
the currently observed linear mode. Downstream kinematic environment
is still favorable for low-level rotation given veering wind profile
characterized by southeasterly surface winds around 15 kt and
mid-level flow from the southwest at 50 kt. Recent ICT VAD data
estimates the 0-1 km SRH is over 150 m2/s2. However, the
thermodynamic environment is less favorable as drier air has moved
in from the east, dropping dewpoints into the mid 60s. Recent
mesoanalysis estimates MLCAPE of less than 1000 J/kg downstream of
the ongoing cluster. Overall, some threat for damaging wind gusts
and a brief tornado still exists but the linear storm mode and
increasingly hostile downstream thermodynamic environment suggest a
gradually diminishing threat.

..Mosier.. 05/19/2017

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

ATTN...WFO...TSA...TOP...ICT...OUN...DDC...

LAT...LON   36779852 38349850 38569616 36969618 36779852 

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SPC MD 784

MD 0784 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR SOUTH-CENTRAL KS…NORTHERN OK

MD 0784 Image


Mesoscale Discussion 0784
NWS Storm Prediction Center Norman OK
0328 PM CDT Fri May 19 2017

Areas affected...South-central KS...Northern OK

Concerning...Severe potential...Watch possible 

Valid 192028Z - 192200Z

Probability of Watch Issuance...40 percent

SUMMARY...Severe threat is increasing across south-central KS and
extreme northern OK.  Hail is the primary threat, though an isolated
tornado can not be ruled out.

DISCUSSION...A narrow corridor of modest boundary-layer heating has
developed from western OK into extreme south-central KS, per
surface-3km lapse rates on the order of 7 C/km.  With minimal CINH
observed across this portion of KS/OK convection is expected to
gradually increase with continued heating, albeit modest due to
extensive cloud cover.  Over the last hour or so thunderstorms have
gradually increased across southwest KS along the cold front.  This
activity is expected to shift east into an air mass characterized by
dew points in the mid 60s with mid 70s temperatures.  While
low-level shear is currently weak, deep-layer shear is more than
adequate for sustained rotating updrafts and a few supercells could
evolve across this region.  Backed low-level flow may contribute to
the tornado potential, though hail is the primary risk.

..Darrow/Kerr.. 05/19/2017

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

ATTN...WFO...TSA...TOP...ICT...OUN...

LAT...LON   36969828 37939804 38479671 38009586 37189582 36609751
            36969828 

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SPC MD 784

MD 0784 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR SOUTH-CENTRAL KS…NORTHERN OK

MD 0784 Image


Mesoscale Discussion 0784
NWS Storm Prediction Center Norman OK
0328 PM CDT Fri May 19 2017

Areas affected...South-central KS...Northern OK

Concerning...Severe potential...Watch possible 

Valid 192028Z - 192200Z

Probability of Watch Issuance...40 percent

SUMMARY...Severe threat is increasing across south-central KS and
extreme northern OK.  Hail is the primary threat, though an isolated
tornado can not be ruled out.

DISCUSSION...A narrow corridor of modest boundary-layer heating has
developed from western OK into extreme south-central KS, per
surface-3km lapse rates on the order of 7 C/km.  With minimal CINH
observed across this portion of KS/OK convection is expected to
gradually increase with continued heating, albeit modest due to
extensive cloud cover.  Over the last hour or so thunderstorms have
gradually increased across southwest KS along the cold front.  This
activity is expected to shift east into an air mass characterized by
dew points in the mid 60s with mid 70s temperatures.  While
low-level shear is currently weak, deep-layer shear is more than
adequate for sustained rotating updrafts and a few supercells could
evolve across this region.  Backed low-level flow may contribute to
the tornado potential, though hail is the primary risk.

..Darrow/Kerr.. 05/19/2017

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

ATTN...WFO...TSA...TOP...ICT...OUN...

LAT...LON   36969828 37939804 38479671 38009586 37189582 36609751
            36969828 

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SPC MD 772

MD 0772 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR EASTERN OK…FAR NORTHWESTERN AR…FAR SOUTHEAST KS…WEST-CENTRAL/SOUTHWEST MO

MD 0772 Image


Mesoscale Discussion 0772
NWS Storm Prediction Center Norman OK
0941 PM CDT Thu May 18 2017

Areas affected...Eastern OK...Far northwestern AR...Far southeast
KS...West-central/southwest MO

Concerning...Severe potential...Watch possible 

Valid 190241Z - 190415Z

Probability of Watch Issuance...60 percent

SUMMARY...One or more downstream watches may be need across portions
of eastern OK, far northwestern AR, far southeast KS, and
west-central/southwest MO as the ongoing convective lines continue
eastward.

DISCUSSION...Regional radar imagery shows several convective lines
across eastern KS and eastern/central OK. Convective trends on the
line across eastern KS have been down over the past hour or so.
Storms within the line may intensify briefly as a result of mergers
and/or interaction with the warm front but the general expectation
is for predominately sub-severe wind gusts. However, some more
cellular development is possible ahead of the line with the overall
environment supportive of rotating updrafts capable of severe hail.
A watch may be needed downstream to cover these potential severe
hazards.

Farther south in northeast OK, ongoing supercells appear to have
experienced upscale growth with recent radar imagery showing a more
eastward storm motion. This developing line may eventually merge
with the well-developed line moving across southern OK and continue
eastward across the remainder of eastern OK and into western AR.
Strengthening low-level flow and ample low-level moisture should
allow for a continued severe threat. The northern extent of the
threat is somewhat questionable given the current storm motion but
portions of southern MO may need a watch and convective trends will
be monitored closely.

..Mosier/Hart.. 05/19/2017

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

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

LAT...LON   38779502 39719408 38889284 34789381 34609543 38779502 

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SPC MD 768

MD 0768 CONCERNING TORNADO WATCH 238…239… FOR NORTHEAST KS AND NORTHWEST MO

MD 0768 Image


Mesoscale Discussion 0768
NWS Storm Prediction Center Norman OK
0706 PM CDT Thu May 18 2017

Areas affected...Northeast KS and northwest MO

Concerning...Tornado Watch 238...239...

Valid 190006Z - 190130Z

The severe weather threat for Tornado Watch 238, 239 continues.

SUMMARY...Threat for tornadoes will continue across northeastern KS
for the next few hours.

DISCUSSION...Recent radar imagery shows four supercells west of TOP
along the warm front extending from just south of MKC westward
through TOP and SLN and then southwestward through DDC. Despite a
messy storm mode, these storms intensified over the past hour or so
and each exhibited strong low-level rotation. Most recent velocity
data have shown more outflow-dominant signatures with some weakening
noted with the two westernmost storms, particularly with the storm
over Ottawa and Saline counties which has weakened significantly as
a result of destructive storm interaction. The storms farther east
over Wabaunsee and Shawnee counties remain quite strong and
strengthening low-level flow coupled with enhanced vorticity along
the warm front will continue to support a tornado threat.

..Mosier.. 05/19/2017

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

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

LAT...LON   38109655 38319792 39059822 39759700 39949356 38459367
            38109655 

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