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Storm Prediction Center


07/21/2019 04:47 PM
SPC - No watches are valid as of Sun Jul 21 20:48:03 UTC 2019
No watches are valid as of Sun Jul 21 20:48:03 UTC 2019.
07/21/2019 04:31 PM
SPC MD 1562
MD 1562 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF EASTERN KANSAS...WEST-CENTRAL/SOUTHWEST MISSOURI
MD 1562 Image

Mesoscale Discussion 1562
NWS Storm Prediction Center Norman OK
0330 PM CDT Sun Jul 21 2019

Areas affected...Portions of eastern Kansas...west-central/southwest
Missouri

Concerning...Severe potential...Watch possible 

Valid 212030Z - 212230Z

Probability of Watch Issuance...60 percent

SUMMARY...Isolated to scattered storms are expected in northeastern
Kansas to southwest Missouri. Expected multicell storm mode will be
capable of isolated large hail and strong/severe wind gusts.
Isolated tornado threat exists along near surface boundary. A WW is
possible later this afternoon.

DISCUSSION...Isolated to scattered storm development is expected
along a composite cold front/outflow boundary across north-central
Kansas into southwest Missouri with some potential for further
development within a weak surface trough in the Pratt/Wichita, KS
vicinity. Current visible satellite trends indicate a deepening
cumulus field near in the Fort Scott, KS vicinity. Low 70s F
dewpoints with low 90s F temperatures has contributed to around 2000
J/kg of MLCAPE in southeastern Kansas. Weak deep-layer shear (25-30
kts) will support marginally organized storms capable of marginally
severe hail and strong/severe wind gusts. Cloud cover in
northeastern Kansas has led to uncertainty as to how many storms
will form in this location. Stronger shear exists there (30-35 kts)
with the influence of a weak mid-level wave/MCV. Storms in this
environment (1000-2000 J/kg MLCAPE) will be similarly capable of
isolated large hail and strong/severe wind gusts. While the overall
tornado potential appears to be low, low-level shear will be
maximized within the I-70 corridor southward to where the boundary
resides near Emporia, KS. An isolated tornado cannot be ruled out.
The greatest hail/tornado threat will exist early in the
multicellular convective cycle. Thereafter, storms are likely to
congeal and pose more of an organized threat for strong/severe wind
gusts. A WW is possible later this afternoon as storm initiation
timing/coverage become more clear.

..Wendt/Guyer.. 07/21/2019

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

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

LAT...LON   38759826 39329806 39529794 39639766 39629711 39449638
            39069515 38649360 37779300 37379353 37259520 37499691
            38079793 38759826 

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07/21/2019 12:40 PM
SPC Jul 21, 2019 1630 UTC Day 1 Convective Outlook
SPC 1630Z Day 1 Outlook
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1133 AM CDT Sun Jul 21 2019

Valid 211630Z - 221200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
KANSAS AND WESTERN MISSOURI...

...SUMMARY...
The most likely area for severe thunderstorms is across eastern
Kansas into western Missouri from around mid-afternoon through
mid-evening. Severe wind gusts are expected, along with severe hail
and possibly a tornado or two.

...Central/eastern Kansas and western/southern Missouri...
An MCV across south-central Nebraska and far north-central Kansas at
midday will move east-southeastward toward northern/western Missouri
through this evening. A decayed MCS across the Missouri Valley has
effectively augmented/shunted a surface boundary southward with
development expected near it later today. As the boundary layer
heats and destabilizes, intensifying thunderstorm development is
most likely to initially occur by around mid-afternoon across
northeast Kansas and possibly far southeast Nebraska near a triple
point to the northeast of a weak surface low. 

Deep-layer shear should generally remain modest at around 25-35 kt
yielding predominately multicell clusters, although a few initial
supercells are possible. Severe hail is possible with initial
updrafts, and a tornado or two is also possible near/just east of
the surface cyclone/related MCV track. However, strong to severe
wind gusts will probably be the main risk with a modest-speed MCS
tracking southeastward into southeast Kansas and western Missouri
into this evening.

...Illinois/Indiana to the Upper Ohio Valley...
Thunderstorms are expected to increase in coverage/intensity this
afternoon particularly near/just south of a south-southeastward
advancing cold front and near/east of a surface low and MCV across
Illinois and Indiana. A moist and moderately/strongly unstable air
mass will support the possibility of locally damaging winds,
although weak deep-layer shear and modest mid-level lapse rates
should temper the overall potential for organized severe. For
additional short-term details regarding the Upper Ohio Valley, see
Mesoscale Discussion 1560. 

...Maine...
The potential for a couple of severe thunderstorms will persist
through the early part of the afternoon across Downeast Maine with
severe hail/wind possible.

...High Plains...
Isolated severe thunderstorms are possible from the Black Hills
southward to the Raton Mesa from mid/late afternoon into this
evening. Deep-layer shear will generally be modest, except in the
Black Hills vicinity where mid-level northwesterlies will be
stronger in association with a shortwave trough moving east across
North Dakota. Isolated severe hail and severe-caliber wind gusts
will be possible.

..Guyer/Wendt.. 07/21/2019

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07/21/2019 04:01 PM
SPC Jul 21, 2019 2000 UTC Day 1 Convective Outlook
SPC 2000Z Day 1 Outlook
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0254 PM CDT Sun Jul 21 2019

Valid 212000Z - 221200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
KANSAS AND WESTERN MISSOURI...

...SUMMARY...
The most likely area for severe thunderstorms is across eastern
Kansas into western Missouri from late this afternoon through
mid-evening. Severe wind gusts are expected, along with severe hail
and possibly a tornado or two.

...DISCUSSION...
No changes are made to the outlook for this issuance.

..Broyles.. 07/21/2019

.PREV DISCUSSION... /ISSUED 1133 AM CDT Sun Jul 21 2019/

...Central/eastern Kansas and western/southern Missouri...
An MCV across south-central Nebraska and far north-central Kansas at
midday will move east-southeastward toward northern/western Missouri
through this evening. A decayed MCS across the Missouri Valley has
effectively augmented/shunted a surface boundary southward with
development expected near it later today. As the boundary layer
heats and destabilizes, intensifying thunderstorm development is
most likely to initially occur by around mid-afternoon across
northeast Kansas and possibly far southeast Nebraska near a triple
point to the northeast of a weak surface low. 

Deep-layer shear should generally remain modest at around 25-35 kt
yielding predominately multicell clusters, although a few initial
supercells are possible. Severe hail is possible with initial
updrafts, and a tornado or two is also possible near/just east of
the surface cyclone/related MCV track. However, strong to severe
wind gusts will probably be the main risk with a modest-speed MCS
tracking southeastward into southeast Kansas and western Missouri
into this evening.

...Illinois/Indiana to the Upper Ohio Valley...
Thunderstorms are expected to increase in coverage/intensity this
afternoon particularly near/just south of a south-southeastward
advancing cold front and near/east of a surface low and MCV across
Illinois and Indiana. A moist and moderately/strongly unstable air
mass will support the possibility of locally damaging winds,
although weak deep-layer shear and modest mid-level lapse rates
should temper the overall potential for organized severe. For
additional short-term details regarding the Upper Ohio Valley, see
Mesoscale Discussion 1560. 

...Maine...
The potential for a couple of severe thunderstorms will persist
through the early part of the afternoon across Downeast Maine with
severe hail/wind possible.

...High Plains...
Isolated severe thunderstorms are possible from the Black Hills
southward to the Raton Mesa from mid/late afternoon into this
evening. Deep-layer shear will generally be modest, except in the
Black Hills vicinity where mid-level northwesterlies will be
stronger in association with a shortwave trough moving east across
North Dakota. Isolated severe hail and severe-caliber wind gusts
will be possible.

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07/21/2019 01:30 PM
SPC Jul 21, 2019 1730 UTC Day 2 Convective Outlook
SPC 1730Z Day 2 Outlook
Day 2 Outlook Image
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1225 PM CDT Sun Jul 21 2019

Valid 221200Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...

...SUMMARY...
Thunderstorms associated with a wind damage threat will be possible
on Monday across parts of the Mid-Atlantic. A few marginally severe
wind gusts are also possible from the mid Mississippi Valley into
the central Appalachians.

...Central Appalachians/Mid-Atlantic...
An upper-level trough will move across the Great Lakes region on
Monday as west-southwesterly mid-level flow remains over the
Mid-Atlantic states. At the surface, a cold front will advance
southward across the central Appalachians with a moist airmass in
place south of the front. Surface dewpoints should be in the lower
70s F will contribute to the development of moderate instability
ahead of the front by late morning. Convection is first expected to
initiate in the higher terrain of the central Appalachians around
midday. Other storms should develop during the afternoon eastward
along the front across the Atlantic Coastal Plains. NAM forecast
soundings along this part of the front at 21Z on Monday have 0-6 km
shear in the 40 to 50 kt range and show very steep low-level lapse
rates suggesting severe storms will be possible. The problem is that
the overlap between the strongest instability and deep-layer shear
is forecast be narrow. Cells that initiate right along the front and
move parallel to the boundary may have potential for damaging wind
gusts and hail. Although the threat area is small, the models are in
reasonable agreement and enough potential exists in the Mid-Atlantic
to add a small slight risk area from northern Maryland into New
Jersey. The slight risk is oriented along the forecast position of
the front during the afternoon.

...Mid Mississippi and Ohio Valleys...
An upper-level trough will move eastward across the Great Lakes and
mid Mississippi Valley on Monday. At the surface, a cold front is
forecast to advance southward into Arkansas, far southeast Missouri
and Kentucky. Ahead of the front, surface dewpoints in the upper 60s
and lower 70s F should result a corridor of instability by midday.
As surface temperatures warm and low-level convergence increases
along the front, scattered thunderstorms appear likely to develop
during the afternoon. Although deep-layer shear should be relatively
weak, steep low-level lapse rates should be enough for marginally
severe wind gusts. The potential should be greatest with cells
develop within the strongest instability.

...MAXIMUM RISK BY HAZARD...
Tornado:   2%     - Marginal
Wind:     15%     - Slight
Hail:      5%     - Marginal

..Broyles.. 07/21/2019

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07/21/2019 03:10 PM
SPC Day 2 Fire Weather Outlook
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook Image
Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0207 PM CDT Sun Jul 21 2019

Valid 221200Z - 231200Z

The ongoing forecast is generally on track, with only minimal
changes to the elevated in southeastern Oregon based on slightly
higher surface winds forecasts during the afternoon and early
evening - particularly in the latest GFS.  

Additionally, a dry-lightning delineation has been added across much
of Nevada, southeastern Oregon, and far southwestern Idaho.  In
these areas, isolated, high-based thunderstorms may produce a few
dry lightning strikes, and fuels will be dry enough to support a
risk of ignition and fire spread.  Although PW values will be
relatively high (around 0.75 inch), 20-30 kt storm motions and
deeply-mixed boundary layer profiles should limit precipitation in
any particular area.

..Cook.. 07/21/2019

.PREV DISCUSSION... /ISSUED 0107 AM CDT Sun Jul 21 2019/

...Synopsis...
The upper-level ridge will start to shift eastward on Monday with
some increasing mid-level southwesterly flow on the western
periphery of the ridge. This will overspread 30 to 40 knot mid-level
flow from northern California into the Pacific Northwest. Some of
these stronger winds are expected to mix toward the surface,
especially where downslope flow is maximized in the lee of the
Sierras. The two primary areas with the greatest chance for elevated
conditions will be from northeast California northeastward into
southeast Oregon and in west central Nevada. Some locally critical
conditions may be possible in west-central Nevada, but the risk area
is too localized at this time to draw a threat area.

In addition, some dry lightning is possible from northern California
northeastward to near the Continental Divide in eastern
Idaho/western Montana. Storms appear to be more isolated and perhaps
a bit more wet in CA/OR and are expected to be more widespread and
dry in the northern Rockies. No dry thunderstorm area has been drawn
at this time, but trends will continue to be monitored to see if an
area needs to be added for some or all of this region in future
outlooks.

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

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