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> July 17-? Plains/MW/GL/OV Severe Weather
joseph507123
post Jul 17 2017, 01:28 AM
Post #1




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From: South Central Minnesota
Member No.: 26,362





An active week coming up.



QUOTE
SPC AC 170549

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1249 AM CDT Mon Jul 17 2017

Valid 171200Z - 181200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHERN PLAINS AND UPPER MS VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL PA TO
VT...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN HIGH PLAINS TO WESTERN LAKE SUPERIOR...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHERN VA
TO NH...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF AZ...

...SUMMARY...
Isolated thunderstorms are expected this afternoon and evening from
South Dakota into northern Minnesota, and during the day from
Pennsylvania into New York and Vermont. Isolated severe storms are
expected from Wyoming into Nebraska, across the Appalachians, and
across southern Arizona.

...Northern Plains/Upper MS Valley...

Strong mid-level short-wave trough is forecast to progress across
AB/SK into MB by 18/00z. This feature will flatten upper ridge over
the northern Plains/upper MS Valley as weak height falls spread
along the international border. Associated surface front should
surge across much of ND by early afternoon with a pre-convective
frontal position expected to extend from near INL, southwest into
central SD at peak heating. Latest model guidance suggests strong
boundary-layer heating will result in surface temperatures soaring
through the upper 90s to near 100F across SD into extreme western MN
which should remove CIN as convective temperatures are breached.
While large-scale forcing for ascent should primarily spread across
southern Canada, frontal forcing and strong surface heating should
result in isolated thunderstorm development after 21z from northwest
MN into central SD. Forecast soundings suggest initial activity may
be high based within veered southwesterly low-level flow. However,
modest mid-high level flow should allow this activity to mature
downstream across MN where buoyancy is forecast to be considerably
higher due to more moist boundary layer. A few supercells could
evolve across northern portions of the SLGT risk where surface-6km
bulk shear is forecast to be on the order of 35kt. Damaging
winds/large hail are the primary severe threats with this activity.

...PA to Southern VT...

Early-morning water vapor imagery depicts a pronounced mid-level
trough digging east-southeast across the Great Lakes/OH Valley
region. Latest model guidance suggests this feature will extend
across western NY/PA at 18z with modest southwesterly high-level
flow expected to extend downstream into southern New England at peak
heating. Relatively cool 500mb temperatures (-10 to -12C) will
overspread much of the northeastern US during the afternoon which
should aid destabilization as surface temperatures warm. Forecast
soundings suggest thunderstorms that develop across this region
could be robust with isolated damaging winds and marginally severe
hail being the primary severe threats.

...AZ...

Subtle day-to-day changes will continue across the southwestern US
early this week as center of upper ridge holds near the Four-corners
region. Convection will once again be modulated by daytime heating
and orographic influences as PW values remain seasonally high with
little notable drying. For these reasons, scattered strong
thunderstorms should develop across the higher terrain during the
late afternoon then propagate toward lower elevations where gusty
winds will be possible, especially if convection organizes due to
adequate cold-pool development.




QUOTE
SPC AC 170605

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0105 AM CDT Mon Jul 17 2017

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER
MIDWEST/UPPER MISSISSIPPI VALLEY AREA...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
SLIGHT RISK...AND EXTENDING WESTWARD ACROSS THE NORTHERN PLAINS INTO
THE HIGH PLAINS REGION...

...SUMMARY...
Isolated to scattered severe thunderstorms will be possible on
Tuesday mainly across the Upper Midwest/upper Mississippi Valley
area.

...Synopsis...
With upper ridging expected to evolve across the central U.S. day
2/Tuesday, faster flow aloft will be generally confined to the
northern tier of the country, on the southern fringe of a northern
Canada vortex.

At the surface, a cold front moving across Ontario and Quebec will
trail southwestward across the upper Great Lakes region and into the
Plains, and westward into the Intermountain region. As the front
shifts southeast across the north central U.S. with time, it is
expected to serve as a focus for diurnal convective development.

...Mid-Missouri Valley east-northeast to Wisconsin...
A cluster of thunderstorms may be ongoing at the start of the
period, spreading east across the northern Plains in a zone of
quasi-geostrophic ascent associated with weak short-wave troughing
ejecting from the northern high Plains. Meanwhile, diurnal
heating/destabilization near/ahead of the advancing cold front
suggests that storms should increase during the afternoon, possibly
evolving into one or more bands of strong/locally severe storms --
aided by fast westerly flow aloft (mid-level flow near 60 kt). Atop
low-level flow with some southerly component, shear will support
rotating updrafts. However, with storm mode expected to trend
toward bands through the afternoon and into the evening, hail and
locally damaging winds would appear to be the main severe risks.
Still, a tornado or two could occur in conjunction with any
stronger/rotating cell. Risk should diminish into the overnight
hours in conjunction with diurnal cooling/stabilization of the
boundary layer.


This post has been edited by joseph507123: Jul 19 2017, 03:46 PM


--------------------
2017-2018 Winter

Winter Weather Advisories: 1

Winter Storm Warnings: 0

Blizzard Warnings: 0

Windchill Warnings: 0

Largest snowfall: 2.75''

Seasonal snowfall: 3.75''

Coldest temperature: 10F

Coldest windchill: -4F
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Juniorrr
post Jul 17 2017, 10:05 PM
Post #2




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I have a feeling there will be lots of last minute changes due to the upcoming ring of fire pattern. Any organized vort riding will create organized systems that will ride the ring.
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ClicheVortex2014
post Jul 17 2017, 11:17 PM
Post #3




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Joined: 21-April 14
From: Athens, Ohio
Member No.: 29,453





QUOTE(Juniorrr @ Jul 17 2017, 11:05 PM) *
I have a feeling there will be lots of last minute changes due to the upcoming ring of fire pattern. Any organized vort riding will create organized systems that will ride the ring.

CIPS favors severe weather in the OV, go figure. But I'm not holding my breath. Expecting hot/humid weather, maybe a nice storm or two.



This post has been edited by ClicheVortex2014: Jul 17 2017, 11:18 PM


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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joseph507123
post Jul 18 2017, 12:35 PM
Post #4




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Posts: 506
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From: South Central Minnesota
Member No.: 26,362





Increasing chance tomorrow for severe weather.
Attached Image


QUOTE
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 PM CDT Tue Jul 18 2017

Valid 191200Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN
PLAINS ACROSS THE UPPER MISSISSIPPI VALLEY...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
SLIGHT RISK FROM THE NORTHERN PLAINS AND UPPER MIDWEST...

...SUMMARY...
Severe storms will be possible over portions of the north-central
U.S. Wednesday and Wednesday night, most likely from eastern South
Dakota, southern Minnesota, northern Iowa into western Wisconsin.

...Synopsis...
Model guidance is consistent indicating a low amplitude mid-level
short wave perturbation will move through the upper ridge over the
northern High Plains tomorrow and turn east-southeastward across the
upper Midwest. This will be associated with a band of stronger
mid/upper level winds forecast to move across the northern Plains
and upper Mississippi Valley.

At the surface, the frontal boundary currently extending across the
upper Midwest is likely to provide a primary focus for
strong-to-severe thunderstorm development especially tomorrow
afternoon and night.

...Northern Plains into the Upper Mississippi Valley...
Scattered mainly elevated convection may be occurring early in the
period over parts of North Dakota and possibly northern South
Dakota. The environment south of the aforementioned boundary is
forecast to become increasing warm/unstable as diabatic heating
occurs beneath an EML plume extending across parts of South Dakota
into southern Minnesota. The cap associated with the EML is likely
to inhibit surface-based storm initiation, particularly south of the
surface front, into the afternoon hours.

The air mass is expected to become quite unstable along/south of the
front from parts of eastern South Dakota across southern Minnesota
and northern Iowa with MLCAPE of 1500-3000 J/kg. Forecast soundings
exhibit veering wind profiles with height as a southwest LLJ
develops by later afternoon and evening, with deep layer shear of
40-50 kt over the region. The severe storm threat is expected to
increase during the afternoon as morning storms in the Dakotas
progress eastward and new storms develop along and north of the
boundary. The environment will be favorable for some initial storms
to develop supercell characteristics, with model guidance suggesting
eventual upscale growth with potential for QLCS bowing segments to
spread east-southeastward by late afternoon and evening. All severe
hazards will be possible with the initial severe storms, with
potential for an increased damaging wind threat developing during
the second half of the period in association with
forward-propagating bowing line segments.

Despite uncertainty in the details of convective storm development
and evolution, sufficient confidence in severe potential exists to
introduce a 15% total severe/SLGT Risk in this outlook. However,
the area will need to be monitored closely for a potential upgrade
in subsequent Day 1 Outlooks.


--------------------
2017-2018 Winter

Winter Weather Advisories: 1

Winter Storm Warnings: 0

Blizzard Warnings: 0

Windchill Warnings: 0

Largest snowfall: 2.75''

Seasonal snowfall: 3.75''

Coldest temperature: 10F

Coldest windchill: -4F
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ClicheVortex2014
post Jul 18 2017, 02:25 PM
Post #5




Rank: F5 Superstorm
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From: Athens, Ohio
Member No.: 29,453





Models are going a little insane for the severe weather tomorrow

GFS



Of course, NAM was on an entire new level


Absolutely the most insane sounding I've ever seen


Tomorrow will be very interesting. Environment will be juiced, so whatever storm mode there'll be, I'm sure significant severe weather will be possible.

Hopefully we don't see a long-track supercell in that environment.

This post has been edited by ClicheVortex2014: Jul 18 2017, 02:29 PM


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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ClicheVortex2014
post Jul 18 2017, 02:37 PM
Post #6




Rank: F5 Superstorm
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From: Athens, Ohio
Member No.: 29,453





Gee, I wonder where the severe weather would be




--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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joseph507123
post Jul 18 2017, 02:51 PM
Post #7




Rank: F5 Superstorm
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Posts: 506
Joined: 20-January 12
From: South Central Minnesota
Member No.: 26,362





QUOTE(ClicheVortex2014 @ Jul 18 2017, 02:37 PM) *
Gee, I wonder where the severe weather would be



GFS thinks 7.38'' for me. blink.gif


--------------------
2017-2018 Winter

Winter Weather Advisories: 1

Winter Storm Warnings: 0

Blizzard Warnings: 0

Windchill Warnings: 0

Largest snowfall: 2.75''

Seasonal snowfall: 3.75''

Coldest temperature: 10F

Coldest windchill: -4F
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ClicheVortex2014
post Jul 18 2017, 04:42 PM
Post #8




Rank: F5 Superstorm
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Posts: 20,985
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From: Athens, Ohio
Member No.: 29,453





hmmm laugh.gif



--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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ClicheVortex2014
post Jul 18 2017, 04:45 PM
Post #9




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From: Athens, Ohio
Member No.: 29,453





Starts out as a few semi-discrete supercells, turns into an MCS






--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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Juniorrr
post Jul 18 2017, 04:50 PM
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blink.gif
Attached thumbnail(s)
Attached Image
 
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ClicheVortex2014
post Jul 18 2017, 07:44 PM
Post #11




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Discrete supercell ongoing in western SD, being picked up by HRRR.



77.5 dBZ on this monster. Baseball size hail and 70 MPH winds. And yes that's a hail spike.

Attached Image


Cross section of the supercell

Attached Image


This post has been edited by ClicheVortex2014: Jul 18 2017, 07:45 PM


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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ClicheVortex2014
post Jul 18 2017, 08:10 PM
Post #12




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Can no longer say I've never seen >80 dBZ. 80.5 dBZ here, in fact

This post has been edited by ClicheVortex2014: Jul 18 2017, 08:11 PM
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Attached Image
 


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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Middle of Nowher...
post Jul 18 2017, 08:49 PM
Post #13




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That thing can just stay out there, tyvm!

That's just nasty.
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ClicheVortex2014
post Jul 18 2017, 09:35 PM
Post #14




Rank: F5 Superstorm
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Posts: 20,985
Joined: 21-April 14
From: Athens, Ohio
Member No.: 29,453





What a joke

(south-central MN)


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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joseph507123
post Jul 18 2017, 09:38 PM
Post #15




Rank: F5 Superstorm
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From: South Central Minnesota
Member No.: 26,362





QUOTE(ClicheVortex2014 @ Jul 18 2017, 09:35 PM) *
What a joke

(south-central MN)

well...


--------------------
2017-2018 Winter

Winter Weather Advisories: 1

Winter Storm Warnings: 0

Blizzard Warnings: 0

Windchill Warnings: 0

Largest snowfall: 2.75''

Seasonal snowfall: 3.75''

Coldest temperature: 10F

Coldest windchill: -4F
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ClicheVortex2014
post Jul 18 2017, 09:56 PM
Post #16




Rank: F5 Superstorm
***

Group: Member
Posts: 20,985
Joined: 21-April 14
From: Athens, Ohio
Member No.: 29,453





QUOTE(joseph507123 @ Jul 18 2017, 10:38 PM) *
well...

laugh.gif

93 MPH gust recorded from that supercell... in the notes of the storm report it says the sensor got destroyed by hail after recording that gust.


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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ClicheVortex2014
post Jul 19 2017, 07:37 AM
Post #17




Rank: F5 Superstorm
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Posts: 20,985
Joined: 21-April 14
From: Athens, Ohio
Member No.: 29,453





Not surprised in the slightest that they're talking about a possible moderate risk upgrade. This has the looks of a classic summer outbreak.



Looks like there's a convective system trying to organize in the Dakotas right now. HRRR has this organization failing.



HRRR was showing more of a MCS/bowing event, now it looks more of a semi-discrete storm mode.



This post has been edited by ClicheVortex2014: Jul 19 2017, 07:42 AM


--------------------
Meteorology undergrad at Ohio University

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978
- ILN Severe Weather Climatology

2017 Weather for Cincinnati

Days >90: 11 (Last: 9/24/17)
Marginal risks: 18 (Last: 8/11/17)
Slight risks: 14 (Last: 8/22/17)
Enhanced risks: 7 (Last: 11/5/17)
Moderate risks: 0 (Last: 6/22/16)
High risks: 0 (Last: 11/17/13)

Realtime Weather on Campus: http://www.phy.ohiou.edu/~scalia/state_street/upload.png
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snowlover2
post Jul 19 2017, 10:27 AM
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From: Dayton,OH
Member No.: 16,713





ILN has a nice write up for the next few days storm chances.
QUOTE
Area Forecast Discussion
National Weather Service Wilmington OH
1119 AM EDT Wed Jul 19 2017

.SYNOPSIS...
Hot and humid conditions will lead to the chance for thunderstorms
at times through the rest of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Heat and humidity will continue to be the main theme today,
with maxima rising well into the 80s and even reaching 90 in
some areas. This combined with relatively high dewpoints will
boost heat index values toward the mid 90s this afternoon.

We should be dry through early afternoon, but during peak
heating a few thunderstorms may develop. It`s difficult to rule
out a thunderstorm just about anywhere within the CWA, but feel
that the most likely location would reside across our northwest
CWA across the Whitewater and Miami Valleys. This is in line
with the latest NMM/ARW model solutions. At this time, am not
expecting any severe weather from storms although certainly
can`t rule out locally gusty winds in any thunderstorm.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Any lingering shower or thunderstorm activity should again
taper off this evening, leaving mostly clear skies overnight. An
overnight MCS will likely drop down across the upper
Mississippi Valley and toward our area through the early morning
hours. The models are in general agreement dissipating the pcpn
associated with this before it reaches our area. However it
will create some uncertainty for the forecast through the
remainder of the day as there could be some lingering cloud
cover and/or some sort of outflow boundary from it that makes it
onto our area. For now though, the models are still suggesting
a bit of a bump up in low level thermal fields through the day
compared to Wednesday. Because of the uncertainty though, for
now will just range highs from near 90 in the northeast to the
lower 90s across the southwest. This will again combine with
dewpoints in the lower 70s to produce heat indices in the upper
90s to around 100 degrees through the afternoon hours. This
will also lead to good instability through the afternoon hours
with the possibility of some thunderstorms to our north feeding
south into the instability late in the day across our north.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Thursday night mid level ridging will be centered over the central
United States with an upper level low over the Hudson Bay. The same
cold front which models have so struggled to get the placement with
is now forecasted to stall out around the Michigan/ Ohio border
before pulling east. Thursday night the boundary is forecast to be
just south of the border with convection likely firing along the
front. There will be many factors in play here though as left over
convection west of region Thursday morning will likely leave a
leftover boundary near the region Thursday night. Predicting the
exact mesoscale layout this far in advance is very difficult and
therefore have just nudged PoPs up at this time. It also should be
noted that at 500 mb a potent short wave will rotating around the
top of the ridge with SFC to 6 km shear values near 40 kts in
central Ohio. Even though the best instability remains south of the
shear there is enough overlap to where some of the storms could
become strong to severe. Given this, SPC has placed the northern
counties of our forecast area in a slight risk for Day 2.

During the day Friday mid level ridging begins to flatten a bit as
the quasi-stationary low that was over North Carolina begins to
retrograde undercutting the ridge. Again, models have continued to
struggle here with how this feature ejects. Friday afternoon
forecast soundings again completely destabilize with ML CAPE values
mostly above 2000 J/kg. Heat indicies Thursday through Saturday will
also be a concern as high temperatures will regularly be around 90 to
lower 90s with dewpoints in the lower 70s. The main question mark
with heat index values will be whether or not convection gets going
and holds down high temperatures at all. Have gone ahead and edged
down high temperatures ever so slightly Friday afternoon due to the
threat of convection.

Saturday the mid level ridge that was over the central United States
this week will start to collapse as the upper level low continues to
pull west/ retrograde. PWATs do come down a little Saturday (around
1.5") but have continued to advertise slightly higher PoPs Saturday
compared to Friday given the weakening mid level ridge.

During the day Sunday an upper level low will dive southeast towards
the Great Lakes with ILN moving into a RRQ. By Monday morning a
surface cold front will begin to work southeast and approach the
Ohio/ Indiana border. Ahead of the front the RRQ from the upper
level jet streak, increased moisture, and ample instability means
PoPs will likely need to continue to be nudged upwards as timing of
the short wave gets nailed down. The ECMWF remains quicker than the
GFS and pushes the front through the area Monday morning while the
GFS pushes the front through the area Monday evening. Behind the
cold front, surface high pressure will build into the region
allowing for slightly below normal temperatures and more pleasant
feeling air Tuesday.


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First Flakes: 10/28/17 Watches:

First 1"+ of Snow:

Biggest Snowfall:

# of Winter Storm Watches:

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snowlover2
post Jul 19 2017, 11:33 AM
Post #19




Rank: F5 Superstorm
***

Group: Member
Posts: 17,056
Joined: 30-December 08
From: Dayton,OH
Member No.: 16,713





GL/OV should be added to title.


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First Flakes: 10/28/17 Watches:

First 1"+ of Snow:

Biggest Snowfall:

# of Winter Storm Watches:

# of Winter Storm Warnings:
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ValpoSnow
post Jul 19 2017, 08:37 PM
Post #20




Rank: F5 Superstorm
***

Group: Member
Posts: 1,708
Joined: 4-January 14
From: Chicago, Illinois
Member No.: 29,059





It's a shame no one is interested in the MCS blasting through N IL at the moment.

If it were in Ohio this board would be lighting up like crazy! lol
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