SPC MD 1460

MD 1460 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR FAR NORTHERN TEXAS PANHANDLE INTO SOUTHERN KANSAS…NORTHERN OKLAHOMA…SOUTHWESTERN MISSOURI…AND EXTREME NORTHWEST ARKANSAS

MD 1460 Image


Mesoscale Discussion 1460
NWS Storm Prediction Center Norman OK
0450 PM CDT Mon Aug 10 2020

Areas affected...Far northern Texas Panhandle into southern
Kansas...northern Oklahoma...southwestern Missouri...and extreme
northwest Arkansas

Concerning...Severe potential...Watch possible 

Valid 102150Z - 102315Z

Probability of Watch Issuance...40 percent

SUMMARY...Vigorous convective development and intensification is
underway across parts of the southern Plains. Damaging gusts are the
primary threat, with some severe hail possible as well. Convective
trends will be monitored for the need of one or more WWs to address
the increasing severe threat.

DISCUSSION...Rapid pulse cellular and multicellular development has
been underway over the past couple of hours, situated within an
instability axis ahead of a southward sagging cold front. Steep
lapse rates (7.5-9 C/km) throughout a deep layer of the troposphere
are currently supporting up to 3000 J/kg MLCAPE. While tropospheric
flow is weak overall, noticeable veering in the sfc-700 mb layer is
promoting some deep-layer shear for marginal storm organization.
Upscale growth of a few convective clusters via cold pool mergers
are possible, where more concentrated damaging wind threats may
ensue. As such, convective trends will continue to be monitored for
upscale organization and the need of potential WW issuance over the
next couple of hours.

..Squitieri/Thompson.. 08/10/2020

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

ATTN...WFO...LZK...SGF...TSA...TOP...ICT...OUN...DDC...AMA...

LAT...LON   36410246 37600140 38340098 38079591 37719440 36989241
            36269206 35549243 35659363 36009600 36219955 36410246 

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SPC MD 1457

MD 1457 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR MUCH OF MISSOURI…FAR EASTERN KANSAS…AND SOUTHERN ILLINOIS

MD 1457 Image


Mesoscale Discussion 1457
NWS Storm Prediction Center Norman OK
0238 PM CDT Mon Aug 10 2020

Areas affected...Much of Missouri...far Eastern Kansas...and
Southern Illinois

Concerning...Severe potential...Watch possible 

Valid 101938Z - 102145Z

Probability of Watch Issuance...60 percent

SUMMARY...A few multi-cell clusters should develop this afternoon,
with damaging winds/hail possible. Trends will be monitored for
possible watch issuance across parts of the region.

DISCUSSION...Regional satellite/radar trends show a variety of
convective development processes occurring across the region. 

  1) An early morning band of severe convection continues to move
northeastward into northeast Missouri, where outflow from the
ongoing MCS has largely stabilized the atmosphere. These storms may
end up merging with the MCS across this area into central Illinois,
where MLCAPE of 3000-4000 J/kg resides. 

  2) A persistent band of elevated convection from northwest
Missouri into southeast Kansas is beginning to show signs of rooting
into the boundary layer. This uptick in intensity is also evident in
visible satellite. This trend appears to pose the greatest
short-term threat.

  3) Boundary layer cumulus is developing across south-central
Missouri amid strong diabatic heating (temperatures in the low 90s
F) and rich low-level moisture (dew point temperatures in the low to
mid 70s F). This process has yielded MLCAPE of 2500-3000 J/kg.

Given the widespread destabilization that has occurred, and the
convective trends noted, convection should become more widespread
throughout the afternoon. Despite ample instability, winds aloft are
generally weak, with only about 20 kt of effective bulk shear
present, with perhaps some enhancement near the MCS in central
Illinois. Thus storms should form into a few mutli-cell clusters,
posing a threat damaging winds and large hail. Convective trends
will be monitored for potential watch issuance this afternoon.

..Karstens/Grams.. 08/10/2020

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

ATTN...WFO...PAH...ILX...LSX...SGF...EAX...TSA...TOP...ICT...

LAT...LON   36799475 37959571 40179296 40118766 36938868 36609234
            36799475 

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SPC Center Public Severe Weather Outlook (PWO)

Public Severe Weather Outlook

PWO Image

PUBLIC SEVERE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1118 AM CDT MON AUG 10 2020

...Severe thunderstorms expected over parts of the Midwest this
afternoon and evening...

* LOCATIONS...
  Central and Eastern Iowa
  Northern Illinois
  Southern Wisconsin
  Northwestern Indiana
  Southwestern Lower Michigan

* HAZARDS...
  Widespread damaging winds, some hurricane force
  A couple of tornadoes
  Isolated large hail

* SUMMARY...
  A derecho producing widespread damaging winds, some of which
  should be intense, is expected to persist and expand east from
  Iowa into parts of the Midwest through this evening.

Preparedness actions...

Review your severe weather safety procedures for the possibility
of dangerous weather today. Stay tuned to NOAA Weather Radio,
weather.gov, or other media for watches and warnings. A watch
means that conditions are favorable for severe thunderstorms
over the next several hours. If a severe thunderstorm warning is
issued for your area, move to a place of safety, ideally in an 
interior room on the lowest floor of a sturdy building.

&&

..Gleason.. 08/10/2020

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SPC MD 1438

MD 1438 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR SOUTHEASTERN KANSAS INTO SOUTHERN MISSOURI

MD 1438 Image


Mesoscale Discussion 1438
NWS Storm Prediction Center Norman OK
0534 PM CDT Sun Aug 09 2020

Areas affected...Southeastern Kansas into southern Missouri

Concerning...Severe potential...Watch unlikely 

Valid 092234Z - 100030Z

Probability of Watch Issuance...5 percent

SUMMARY...A few damaging wind gusts and perhaps a couple severe
hailstones may accompany the stronger storms. A WW issuance is not
expected given the isolated, brief nature of the threat.

DISCUSSION...A southward surging outflow boundary, originating from
an earlier MCS/associated cold pool, has recently resulted in the
initiation of isolated, mainly multicellular convection across
portions of southeast KS into southern MO. Temperatures in the 90s,
with low to mid 70s dewpoints, characterize the airmass ahead of the
outflow boundary, resulting in 3000+ J/kg MLCAPE. Weak deep-layer
flow and resultant vertical shear suggest that even the more intense
storms will struggle to organize and sustain themselves in the
ambient environment. However, latest mesoanalysis depicts locally
stronger low-level shear in close proximity to the boundary, which
may encourage brief instances of updraft rotation. As such, brief
periods of damaging gusts and perhaps a couple severe hail stones
may exist. Nonetheless, the severe threat is expected to remain
isolated and short-lived overall, with the latest HRRR runs not
depicting much in the way of further convective development. As
such, a WW issuance is not expected.

..Squitieri/Dial.. 08/09/2020

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

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

LAT...LON   38469692 38159571 37759340 37719171 38039048 37789034
            37639030 37379031 37019045 36699068 36399103 36159193
            36199260 36629367 37019511 37559645 38469692 

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SPC MD 1431

MD 1431 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR NORTHEAST KS…SOUTHEAST NE

MD 1431 Image


Mesoscale Discussion 1431
NWS Storm Prediction Center Norman OK
0346 AM CDT Sun Aug 09 2020

Areas affected...Northeast KS...Southeast NE

Concerning...Severe potential...Watch unlikely 

Valid 090846Z - 091045Z

Probability of Watch Issuance...5 percent

SUMMARY...A few strong storms are possible over southeast NE and
northeast KS during the next few hours.

DISCUSSION...A line of multicellular storms, extending from roughly
35 miles east of HSI (in southeast NE) southward to about 20 miles
northeast of HUT (in central KS), has developed and intensified over
the past hour or so. This line developed along the leading edge of
modest low-level jet extending from the TX Panhandle into central
KS. Steep mid-level lapse rates are supporting moderate buoyancy and
initially strong updrafts. However, vertical shear is modest and
overall storm organization is weak. That trend is generally expected
to continue, resulting in brief, strong updrafts with little severe
potential. Given the hostile low-level thermodynamic environment and
lack of more favorable vertical shear, these storms will likely
dissipate within the next two hours or so.

..Mosier/Hart.. 08/09/2020

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

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

LAT...LON   39599786 40359804 40839836 41189826 41479739 41039676
            39849673 38239691 38049779 39599786 

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SPC MD 1430

MD 1430 CONCERNING SEVERE THUNDERSTORM WATCH 422… FOR SOUTHEAST SD…FAR NORTHEAST NE…FAR SOUTHWEST MN…FAR NORTHWEST IA

MD 1430 Image


Mesoscale Discussion 1430
NWS Storm Prediction Center Norman OK
0146 AM CDT Sun Aug 09 2020

Areas affected...Southeast SD...Far Northeast NE...Far Southwest
MN...Far Northwest IA

Concerning...Severe Thunderstorm Watch 422...

Valid 090646Z - 090745Z

The severe weather threat for Severe Thunderstorm Watch 422
continues.

SUMMARY...Threat for strong wind gusts will continue across
southeast SD and far northeast NE, and into far southwest MN and far
northwest IA over the next hour or so.

DISCUSSION...Organized convective line continues to move
northeastward across southeast SD and adjacent far northeast NE.
Recent storm motion was estimated at 45-47 kt, bringing the line to
the SD/MN/IA border intersection a little after 07Z. Echo tops have
remained fairly consistent over the past hour or so, with the
strongest cores currently arcing from Hutchinson County SD to Boone
County NE. Near-severe gusts of 49 kt and 41 kt were recently
measured at KHON and KYKN, respectively. 

Low-level stability exists downstream, but the organized character
of the convective line (evidenced by the well-defined rear-inflow
jet on radar imagery) and steep mid-level lapse suggest the line
should maintain its intensity for at least the next hour or so. As a
result, the severe wind threat is expected to persist into far
southwest MN and far northwest IA.

..Mosier.. 08/09/2020

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

ATTN...WFO...MPX...FSD...OAX...ABR...LBF...

LAT...LON   44349979 44739849 44719585 43149556 41959787 43279878
            44349979 

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SPC MD 1345

MD 1345 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR NORTHERN KANSAS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA

MD 1345 Image


Mesoscale Discussion 1345
NWS Storm Prediction Center Norman OK
0206 PM CDT Sun Jul 26 2020

Areas affected...Northern kansas southeast Nebraska and southwest
Iowa

Concerning...Severe potential...Watch unlikely 

Valid 261906Z - 262100Z

Probability of Watch Issuance...20 percent

SUMMARY...A couple of strong/severe storms with damaging winds and
isolated large hail will be possible this afternoon and evening. A
weather watch is not expected.

DISCUSSION...Afternoon surface analysis showed a slow moving cold
front across much of the central Plains into the Midwest. This front
was associated with a high-latitude shortwave trough ejecting
eastward over the Dakotas. Lift from the shortwave trough is
forecast to glance the frontal zone later this afternoon and
evening. Strong heating along the frontal zone is contributing
2000-3000 J/kg of MLCAPE given dewpoints in the lower 70s F.
Inhibition is beginning to weaken, and recent cumulus development
suggests the atmosphere is continuing to destabilize. Stronger shear
is forecast to remain displaced on the northern side of the
boundary. This should serve to limit the overall organization of
convective elements. However, a couple of severe storms may develop
with a threat for damaging winds and isolated large hail.
Considerable uncertainty exists in the coverage of severe storms. As
a result, a weather watch appears unlikely at this time.

..Lyons/Hart.. 07/26/2020

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

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

LAT...LON   38780107 39600096 40479939 40959825 41399709 41629631
            41649540 41189454 40389426 39689493 39219659 38669936
            38559990 38510035 38780107 

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SPC MD 1314

MD 1314 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF THE WESTERN GREAT BASIN

MD 1314 Image


Mesoscale Discussion 1314
NWS Storm Prediction Center Norman OK
0133 PM CDT Wed Jul 22 2020

Areas affected...portions of the western Great Basin

Concerning...Severe potential...Watch unlikely 

Valid 221833Z - 222030Z

Probability of Watch Issuance...5 percent

SUMMARY...Scattered thunderstorm development is expected by the mid
afternoon hours, and will pose an isolated risk for strong downburst
winds and perhaps severe hail.

DISCUSSION...Recent GOES visible and IR imagery across the western
Great Basin show deepening cumulus with cooling cloud top
temperatures developing off of higher terrain across eastern NV as
well as within a broad deformation zone ahead of an approaching
upper-level low off the CA coast. A few transient lightning strikes
have also been noted over the past hour. While sustained convection
has yet to develop, these trends suggest that more robust convective
initiation is probable in the next 1-2 hours. Elevated instability
remains somewhat marginal (widespread MUCAPE values near 500 J/kg),
but low-level lapse rates have already steepened to 8-9 C/km across
a broad region as a result of deep boundary-layer mixing. 

Once convection becomes established, a gradual increase in storm
intensity is expected through the late afternoon hours as continued
boundary-layer warming, coupled with the steep mid-level lapse rates
noted in morning soundings, helps augment instability. Additionally,
the approach of stronger flow aloft associated with the upper-level
wave will help strengthen deep layer shear through the afternoon.
The aforementioned steep low-level lapse rates will support the
potential for sporadic strong to severe downburst winds. A few
instances of severe hail will be possible with any stronger, more
organized storm, but widespread severe convection does not appear
likely and precludes the need for a watch.

..Hart/Moore.. 07/22/2020

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

ATTN...WFO...BOI...LKN...REV...MFR...STO...

LAT...LON   39921770 40191866 40302023 40292108 40912140 41472089
            41992003 42311903 42311769 42351689 41731478 40711426
            39041435 39231540 39521662 39921770 

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SPC MD 1297

MD 1297 CONCERNING SEVERE THUNDERSTORM WATCH 389…390… FOR WESTERN/SOUTHERN NEBRASKA AND WESTERN KANSAS

MD 1297 Image


Mesoscale Discussion 1297
NWS Storm Prediction Center Norman OK
1129 PM CDT Mon Jul 20 2020

Areas affected...Western/southern Nebraska and western Kansas

Concerning...Severe Thunderstorm Watch 389...390...

Valid 210429Z - 210600Z

The severe weather threat for Severe Thunderstorm Watch 389, 390
continues.

SUMMARY...Overall severe-weather potential continues to diminish
in/near Severe Thunderstorm Watches 389/390, with a lingering risk
mainly across northwest Kansas. Watch 389 will likely expire by/at
05Z.

DISCUSSION...A linearly organized band of storms continues to settle
south-southeastward across northwest Kansas, with the stronger
updrafts embedded within the westernmost portion of the line just
south of I-70 and Goodland/Colby areas as of 1015 pm MDT. Cloud tops
have tended to gradually warm and the advancing cluster should
continue to encounter increasing boundary layer inhibition and
lesser buoyancy with southward extent. Thus, the severe-weather
potential should continue to trend increasingly marginal over the
next 1-2 hours, and an additional Watch issuance or extension is not
expected.

Farther north, additional upscale quasi-linear growth could occur
with multiple clusters ongoing across south-central Nebraska. While
a localized severe thunderstorm cannot be entirely ruled out,
increasingly stable nocturnally/convectively influenced inflow
should keep the severe potential limited.

..Guyer.. 07/21/2020

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

ATTN...WFO...OAX...GID...LBF...DDC...GLD...

LAT...LON   39300187 39610062 40559964 41359958 41989990 41459820
            40519885 39239926 38720144 39300187 

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SPC MD 1287

MD 1287 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR CENTRAL/SOUTHERN NE…NORTHERN KS

MD 1287 Image


Mesoscale Discussion 1287
NWS Storm Prediction Center Norman OK
0214 AM CDT Mon Jul 20 2020

Areas affected...Central/southern NE...Northern KS

Concerning...Severe potential...Watch unlikely 

Valid 200714Z - 200915Z

Probability of Watch Issuance...5 percent

SUMMARY...Widespread thunderstorms are expected overnight. Localized
severe wind/hail is possible, though the threat appears relatively
limited. Watch issuance is not expected.

DISCUSSION...At 07Z, convection is increasing in coverage across
central NE into northern KS, in advance of a convectively enhanced
shortwave trough moving eastward out of the central High Plains.
While deep-layer shear is generally weak across the region (in the
20-30 kt range), convection is expected to continue increasing in
coverage within a warm-advection regime attendant to the shortwave.
Moderate MUCAPE (1000-2000 J/kg) will support a localized hail risk
with the strongest newer updrafts, while continued consolidation of
convection may result in at least temporary bowing structures
capable of locally damaging wind. 

The greatest relative risk will likely be over northern KS and far
southern NE, in closer proximity the primary surface boundary and
somewhat greater elevated buoyancy. The overall threat is expected
to remain too limited for watch issuance.

..Dean/Edwards.. 07/20/2020

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

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

LAT...LON   39169930 39279988 39400031 39520044 40440012 40730002
            41079990 41369978 41489957 41699920 41829886 41829824
            41709746 41279695 40839669 40549653 39809618 39519604
            39229643 39149732 39139790 39149881 39169930 

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