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> July 18-20 Plains/MW/GL/OV Severe Weather, SPC Risk Level; Day 1 Moderate Risk: Forecasts and OBS
Removed_Member_snowlover2_*
post Jul 19 2018, 06:09 PM
Post #21







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QUOTE(grace @ Jul 19 2018, 07:02 PM) *
Iowa tornado video of it going through downtown Marshalltown:
https://twitter.com/BuzzFeedStorm/status/1020079627031625730

Just incredible.
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Removed_Member_WeatherMonger_*
post Jul 19 2018, 06:42 PM
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Attached Image

QUOTE
Mesoscale Discussion 1091
NWS Storm Prediction Center Norman OK
0626 PM CDT Thu Jul 19 2018

Areas affected...Northeast Missouri into western and central
Illinois.

Concerning...Severe potential...Watch likely

Valid 192326Z - 200030Z

Probability of Watch Issuance...80 percent

SUMMARY...Storms in southeast Iowa are expected to grow upscale
through the evening with an increasing wind damage threat. A
downstream severe thunderstorm watch is likely within the hour.

DISCUSSION...Latest HRRR guidance suggests the storms in southeast
Iowa may continue to grow upscale through the evening. Effective
shear of 40 to 45 knots per the latest RAP mesoanalysis and MUCAPE
of 2000 to 2500 J/kg supports continued growth of these existing
storms. If a strong enough cold-pool develops, a MCS may develop and
persist through much of the overnight period. Wind damage will be
the primary threat as these storms organize into a more linear mode.
Once these storms congeal into a linear segment, the tornado risk
will likely decrease as low-level shear vectors will be oriented
mostly parallel to any linear development. Some hail is possible,
but modest mid-level lapse rates (6 to 6.5 C/km) will preclude a
greater hail threat. A severe thunderstorm watch will likely be
needed within the hour to cover the damaging wind threat into the
overnight period.

..Bentley.. 07/19/2018
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Removed_Member_snowlover2_*
post Jul 19 2018, 07:08 PM
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There's the watch. Springfield barely in it.

Attached Image
QUOTE
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 286
NWS Storm Prediction Center Norman OK
650 PM CDT Thu Jul 19 2018

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
parts of western and central Illinois
portions of northeast and east central Missouri

* Effective this Thursday night and Friday morning from 650 PM
until 200 AM CDT.

* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Scattered large hail events to 1.5 inches in diameter possible
A tornado or two possible

SUMMARY...A cluster of strong/severe storms will continue shifting
southeast out of Iowa and into northwest Missouri/west-central
Illinois over the next few hours -- and possibly continuing into
central Illinois later this evening. Damaging winds will likely be
the primary severe risk, though hail may also occur over the next
couple of hours. A tornado or two will also be possible --
particularly in the next 1-2 hours over western portions of the
watch.

The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 15 miles west northwest
of Quincy IL to 30 miles north northeast of Salem IL. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 283...WW 284...WW 285...

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
30030.

...Goss
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Removed_Member_WeatherMonger_*
post Jul 19 2018, 07:13 PM
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Thought I posted it here as well. Started a thread at the other site as well. Trying to get a handle on how to proceed over there.

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Juniorrr
post Jul 19 2018, 09:37 PM
Post #25




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Yea morning convection will likely screw our chances in OH(has it impacting around 7-10am). Perhaps some cold funnels on Saturday.
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Removed_Member_snowlover2_*
post Jul 19 2018, 09:52 PM
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QUOTE(Juniorrr @ Jul 19 2018, 10:37 PM) *
Yea morning convection will likely screw our chances in OH(has it impacting around 7-10am). Perhaps some cold funnels on Saturday.

If there is morning storms and they get out quick enough we should be good. NAM's and HRRR not helping by showing different outcomes for tomorrow. Going to be a wait and see.
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FireworkWX03
post Jul 19 2018, 11:17 PM
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QUOTE(snowlover2 @ Jul 19 2018, 10:52 PM) *
If there is morning storms and they get out quick enough we should be good. NAM's and HRRR not helping by showing different outcomes for tomorrow. Going to be a wait and see.


Lots of different possibilities when you throw in the HRW ensembles too. The HRRR is the most interesting for Ohio, it might be picking up on a feature ILN is talking about:

QUOTE
In addition there is another area of concern across primarily
central portions of the region from around Hardin County Ohio
southward to around Scioto County and surrounding areas. This
area is closer to a boundary. This threat is a lot more of a
conditional threat. If there can be enough breaks in the clouds
allowing for the atmosphere to recover this could be another
focus area for severe weather with damaging winds. With the
location near the boundary, shear and the potential for
additional isolated tornadoes will be possible as well. If
storms are able to rotate, isolated large hail will be possible.
There is also the potential that if the atmosphere does not
recover as much across this area that the severe potential will
be less. Looking at the latest model solutions, believe there is
at least some threat for severe weather across this region
during the late afternoon and into the evening.


That would get the severe weather threat all the way up to the CLE CWA border, putting much more of the state in play.
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ClicheVortex2014
post Jul 19 2018, 11:42 PM
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I've been sleeping on severe potential. Got a new laptop plus I've been really busy. Tomorrow looks really interesting... shame I work all day.

Here's my contribution at nearly 1AM... clouds. Surface low is in northern Iowa right now. The debris clouds from the convection in Illinois is pushing east, not really building just expanding a bit. It has about 12 hours to break up before we can start talking about it messing things up for us.



--------------------
Meteorology undergrad at Ohio University (weather on campus)

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

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
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FireworkWX03
post Jul 19 2018, 11:52 PM
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A reminder why Severe Thunderstorm Warnings are no joke:

https://www.nbcnews.com/news/us-news/unknow...ri-lake-n893011

At least 11 dead after a tourist boat capsized in Branson, Missouri. That's almost triple the total of people that have died in tornadoes this entire year. Condolences to the family members.
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Removed_Member_snowlover2_*
post Jul 20 2018, 12:42 AM
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New day 1 expanded enhanced and added a moderate risk area.
Attached Image

QUOTE
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1234 AM CDT FRI JUL 20 2018

VALID 201200Z - 211200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM WESTERN TN
TO SOUTHERN IN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM LOWER MI TO
MS AND AL...

..SUMMARY

SEVERE THUNDERSTORMS WILL DEVELOP ACROSS THE OHIO AND TENNESSEE
VALLEY REGION INTO THE MID-SOUTH FRIDAY. VERY LARGE HAIL, DAMAGING
WINDS, AND A FEW TORNADOES CAN BE EXPECTED. ISOLATED SEVERE STORMS
ARE POSSIBLE ACROSS THE CENTRAL HIGH PLAINS.

..OH/TN VALLEYS INTO THE MID-SOUTH

STRONG MID-LEVEL JET, IN EXCESS OF 60KT AT 500MB, IS FORECAST TO DIG
SOUTHEAST ACROSS THE MID-MS VALLEY REGION FRIDAY AS PRIMARY
MID-LEVEL CIRCULATION SETTLES INTO THE SOUTHERN LAKE MI AREA DURING
THE LATTER HALF OF THE PERIOD. WITH 500MB HIGH CENTERED OVER THE
SOUTHERN HIGH PLAINS, PRONOUNCED MID-LEVEL DIFFLUENCE WILL EXTEND
ACROSS A GOOD PORTION OF THE OH VALLEY INTO THE CENTRAL GULF STATES.
THIS LARGE-SCALE REGIME WILL PROVE FAVORABLE FOR ROBUST CONVECTION
ALONG THE EASTERN PLUME OF SOUTHERN PLAINS HEAT DOME.

EARLY THIS MORNING A SUBSTANTIAL RESERVOIR OF INSTABILITY EXISTS
FROM THE CENTRAL PLAINS INTO THE LOWER MS VALLEY. SEVERAL POCKETS OF
STRONG/SEVERE THUNDERSTORMS HAVE EVOLVED WITHIN A WARM ADVECTION
CORRIDOR ACROSS SOUTHERN KS/NORTHERN OK AND AHEAD OF THE LARGER
TROUGH OVER WI/IL. THIS ACTIVITY IS NOT CURRENTLY EXPECTED TO GROW
UPSCALE PRIOR TO DAYBREAK. AS A RESULT, EXTREME BUOYANCY IS EXPECTED
TO DEVELOP ACROSS THE MID-SOUTH INTO SOUTHERN IN WITHIN
SOUTHWESTERLY LOW-LEVEL FLOW WHERE SURFACE TEMPERATURES ARE EXPECTED
TO WARM RAPIDLY AHEAD OF SYNOPTIC FRONT. THE AFOREMENTIONED
MID-LEVEL JET WILL DIG INTO THIS REGION DURING THE DAY ENHANCING
SHEAR PROFILES AND VENTING ALOFT FOR ROBUST UPDRAFTS.

CURRENT THINKING IS STRONGER FORCED REGIONS OF IN/LOWER MI WILL
EASILY CONVECT BY EARLY AFTERNOON AND A POSSIBLE SQUALL LINE COULD
EVOLVE AFTER 18Z WHERE MID-LEVEL BACKING AND HEIGHT FALLS ARE MORE
EVIDENT. HOWEVER, MORE INTENSE THUNDERSTORMS ARE EXPECTED TO DEVELOP
TOWARD 21Z FARTHER SOUTH ACROSS WESTERN KY, THEN INTO WESTERN TN BY
LATE AFTERNOON. FORECAST SOUNDINGS ACROSS THE MDT RISK REGION ARE
QUITE IMPRESSIVE REGARDING BUOYANCY WITH SBCAPE ON THE ORDER OF
5000-6000 J/KG AND SFC-6KM SHEAR APPROACHING 60KT. ENVIRONMENTAL
PARAMETERS STRONGLY FAVOR SUPERCELLS ACROSS THIS REGION AND VERY
LARGE HAIL COULD ACCOMPANY THIS ACTIVITY. IN ADDITION, TORNADO
THREAT WILL BE GREATEST WITH THESE DISCRETE STORMS THAT WILL
PROPAGATE STRONGLY SOUTHEAST AROUND 25KT. IF THIS REGION IS NOT
CONVECTIVELY CONTAMINATED PRIOR TO MID AFTERNOON THERE IS SOME
CONCERN THAT A HIGHER TORNADO THREAT MAY BE EMBEDDED IN THIS REGION.
WILL MONITOR MESOSCALE DETAILS AND ADDRESS THIS CONCERN IN LATER
OUTLOOKS. OTHERWISE, MULTIPLE SEVERE THUNDERSTORM CLUSTERS SHOULD
EVOLVE ACROSS THE MID-SOUTH DURING THE EVENING WHICH SHOULD
PROPAGATE ACROSS NORTHERN MS/AL WITH AN ATTENDANT THREAT FOR LARGE
HAIL/DAMAGING WINDS.

..CENTRAL HIGH PLAINS

WEAK ISENTROPIC ASCENT MAY GENERATE CONVECTION EARLY IN THE PERIOD
ACROSS PORTIONS OF THE HIGH PLAINS. SEVERAL CAMS SUGGEST THIS
ACTIVITY COULD GROW UPSCALE AS IT PROPAGATES SOUTHEAST ALONG A
CORRIDOR OF WARM ADVECTION TOWARD SOUTHERN KS. HOWEVER, CONFIDENCE
IN THIS SCENARIO IS NOT PARTICULARLY HIGH. OF MORE CONCERN WILL BE
THE REGION OF EASTERN CO/WESTERN KS LATER IN THE DAY. EASTERLY
UPSLOPE FLOW AND STRONG BOUNDARY-LAYER HEATING SHOULD ALLOW AT LEAST
ISOLATED THUNDERSTORMS TO EVOLVE ACROSS THIS REGION AS TEMPERATURES
WARM INTO THE UPPER 90S. DEEP-LAYER SHEAR WILL BE MORE THAN ADEQUATE
FOR SUSTAINING ORGANIZED UPDRAFTS AND A FEW SUPERCELLS COULD EVOLVE
THAT WOULD POSE A THREAT OF LARGE HAIL/DAMAGING WINDS.
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ClicheVortex2014
post Jul 20 2018, 01:24 AM
Post #31




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With a moderate risk issued, saying this is an obvious severe weather outbreak setup is a pretty dull statement. But wow. This almost makes not tracking the weather worth it.



--------------------
Meteorology undergrad at Ohio University (weather on campus)

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

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
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FireworkWX03
post Jul 20 2018, 01:27 AM
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Wow -- ENH/SLGT all the way up to Michigan! Now my interest is really piqued. Guess I shouldn't have been a naysayer. tongue.gif

HRRR and SPC both say forcing is just strong enough that convection kicks off in the mid-afternoon from S. MI down to the Ohio River even with the influence of mid-morning convection. IWX and DTX have not been under a single watch this year, TOR or SVR T'STM, and I'm assuming that will be ending shortly.
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ClicheVortex2014
post Jul 20 2018, 01:33 AM
Post #33




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Latest HRRR runs have the Illinois cluster strengthening, hitting around 8AM. Sun may poke out a few times before some potential development in the cold pool a few hours later, then the final round in the afternoon.





This post has been edited by ClicheVortex2014: Jul 20 2018, 01:35 AM


--------------------
Meteorology undergrad at Ohio University (weather on campus)

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

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
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ClicheVortex2014
post Jul 20 2018, 01:39 AM
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QUOTE(ClicheVortex2014 @ Jul 20 2018, 12:42 AM) *
I've been sleeping on severe potential. Got a new laptop plus I've been really busy. Tomorrow looks really interesting... shame I work all day.

Here's my contribution at nearly 1AM... clouds. Surface low is in northern Iowa right now. The debris clouds from the convection in Illinois is pushing east, not really building just expanding a bit. It has about 12 hours to break up before we can start talking about it messing things up for us.


Satellite imagery update almost exactly 2 hours later. Stuff popping in Indiana but nothing back behind the cluster in IL. That's a good sign but we do know that redevelopment behind the cluster is at least possible in the late morning.



This post has been edited by ClicheVortex2014: Jul 20 2018, 01:42 AM


--------------------
Meteorology undergrad at Ohio University (weather on campus)

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

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
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FireworkWX03
post Jul 20 2018, 01:53 AM
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05Z HRRR at 23Z. There has been a consistent signal for a feisty storm or two in Northern Ohio for several runs as the warm front comes through around 18Z. Attendant cloud cover breaks (variable clouds all morning really) and a narrow band of CAPE/shear for a few hours. NAM has it as well. Nothing crazy and I'm not expecting a ton but interesting nonetheless. The mother-you-know-what'n legend Dick Goddard always said a warm front is like a cat and a cold front is like a dog... you always know what the latter will do but never the former. The HRRR was also excellent at nailing that feature that came through back in April that had a couple touchdowns surrounded by stratiform rain. Last time I saw it predict anything with this kind of consistency (the updraft helicity streak through Cuyahoga County). Although I admittedly only check it when I think I might personally get storms. Will be watching as this system so far has surprised.

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Removed_Member_snowlover2_*
post Jul 20 2018, 03:17 AM
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Haven’t seen a write up from ILN like this in a long time.

Area Forecast Discussion
National Weather Service Wilmington OH
350 AM EDT Fri Jul 20 2018

.SYNOPSIS...
A warm front will move north into the region today, as a area of low
pressure develops and moves into the southern Great Lakes. This low
will remain in place through the next several days, bringing chances
of showers and thunderstorms. An upper-level trough will remain in
place going into next week, with temperatures remaining slightly
below normal.

&&

.NEAR TERM /THROUGH TODAY/...
A complicated and potentially hazardous scenario is setting up
for today, in a very un-July-like weather pattern for the Great
Lakes and Ohio Valley.

An area of surface low pressure is currently analyzed to be in
northeastern Iowa. Aloft, the clear swirl of mid-level low
pressure is evident in the same region, though GOES-E water
vapor imagery suggests there may be some embedded mesoscale
vorticity maxima within the envelope of the larger low pressure
system. This is actually kind of an important factor for the
forecast today, which will be discussed a little later. Over the
middle Ohio Valley and the ILN CWA, conditions are still rather
stable, though this is beginning to change as theta-e advection
is already taking place at and above 850mb. With 925mb theta-e
advection just upstream, moisture convergence just ahead of this
elevated warm front is helping to lead to the expected first
round of convective development -- currently over southern
Indiana. There is solid model agreement that suggests this
activity will continue to grow over the next few hours, and
cross the ILN CWA between 10Z-16Z. As it does so, it is likely
to outrun the surface warm front, which at this early hour is
still somewhat under-developed and hard to pick out on
observations. Nonetheless, building elevated instability will
support a marginal hail threat with this activity. Model
soundings also suggest that the boundary layer will be stunted
by a 900mb inversion, but this inversion will be weakening with
time, perhaps allowing some gusty winds to also occur. Overall,
though, the risk for severe weather with this first round of
storms appears to be fairly low -- perhaps increasing ever so
slightly as the storms exit the ILN CWA to the east.

A lull is expected after the morning activity, due to two
factors. For one, this is just typical meteorology -- that
conditions should at least briefly stabilize behind a round of
convection. For two, the multi-spoked nature of the mid-level
low will mean that additional forcing will be coming in a little
bit later in the day -- likely working its way toward the
forecast area by early to mid afternoon. Before that occurs, the
surface warm front (moving just behind the morning convection)
will move through the region. This front will be oriented in a
NNW-to-SSE fashion, and the true warm sector will be somewhat of
a narrow wedge, extending from the lower Tennessee Valley
through Indiana, western Ohio, and even into southern Michigan.
Boundary layer flow will be mainly southerly, allowing for
theta-e advection to take place. However, the flow aloft will be
much more westerly, and these westerly winds will be advecting a
much different type of air -- drier and cooler. Thus, there is
an expectation for a plume of steep mid-level lapse rates to set
up to the south of the low center, focused a little southwest of
the ILN CWA, but certainly getting into the area to an extent.
Where this combines with the building warmth and moisture near
the surface, instability will become quite notable -- with
surface-based CAPE values of as much as 2500-3000 J/kg in the
southwestern ILN CWA, and even as high as 4000-5000 J/kg
further to the southwest in central and western Kentucky.

Before going any further, it should be noted that there are some
forecast uncertainties related to exact convective mode and
timing, particularly within the suite of convective-allowing
models, which have not been terribly consistent with each other
(or with the standard NAM/GFS output). In particular, some of
the WRF runs are suggesting enough additional early-day
convection to blow out the instability for the afternoon, a
scenario unsupported by the HRRR/NAM/GFS.

Assuming the instability develops into the western ILN CWA as
expected, a scenario with a few thousand J/kg of CAPE is not
altogether unsurprising for July. What makes this setup unusual
is the presence of the stacked low, and its impact on the wind
fields. Aloft, there is some pretty solid diffluence to the
southeast of the low center, which will be moving into the ILN
CWA during favorable diurnal timing in the afternoon. As
mentioned earlier, there will also be periods of favorable lift
from the very small-scale vorticity maxima rotating around the
main upper low. Finally, at the surface, the presence of the
warm front (eventually sort of occluding into the trailing cold
front) may also act as a focus for development. What should
result is one or more curved bands of convective development
(initially discrete and possibly supercellular) that develop
during the mid afternoon through evening.

Winds in the warm sector will be solidly southerly (and with
BUFKIT soundings indicating some clear-air gust potential to
around 20 knots). These winds turn to the southwest at 850mb and
to the west above 700mb. Overall values for deep-layer shear
are perhaps marginal in the ILN CWA (better further to the
southwest) but the magnitude of both the directional and speed
shear in the lowest 2km is flat-out impressive for July (and not
even bad for other parts of the year).

All together, this second round of storms will certainly be
capable of severe weather, and all threats are possible. There
is enough deep instability to support a risk of large hail,
though the steeper lapse rates and better deep-layer shear support
this threat being little greater to the southwest of the ILN
CWA (where the SPC moderate risk for hail is in effect). Heavy
rainfall will be a concern in some of the expected deep
convective cores, though this threat may be localized where some
training or back-building occurs. The threat for damaging wind
threat will certainly exist, especially with some dry air in the
mid-levels and the potential for the development of clusters
that forward-propagate south or southeast into the instability.
This is one thing that has been observed in the real world several
times in the past 12 hours or so, but that current HRRR runs
have not really captured -- that storm clusters growing upscale
into the instability is certainly something that could occur.
The wind profiles are a little bit messy enough aloft to lead to
some questions about how long cells that develop in the ILN CWA
can stay purely discrete, but any congealing clusters will
perhaps enhance the threat for winds as well.

Last but certainly not least to mention is the tornado threat,
which must be discussed with low-level winds like these in a
favorable thermodynamic environment. It is likely that there
will be areas of even further backed wind flow (SSE) in the
vicinity of the warm front, perhaps extending all the way north
into northwestern Ohio and northeastern Indiana. Forecast
hodographs through this area show well-curved shapes, with
surface winds that are around 10-15 knots sustained -- not just
a negligible few knots like a typical summer scenario. The
amount of instability being forecast, and some of the other
factors like the mid-level lapse rates, are not as important to
tornado forecasting as what is going on with the winds near the
surface. For that reason, it is believed that the tornado
threat is probably just as great in the northwestern ILN CWA as
it is in the southwestern ILN CWA. If there is any delineation
to be made across the forecast area for any of the severe
threats, it is that both shear and instability are weaker with
eastward extent, leading to more of a marginal severe threat
near and east of US-23.

Max temperatures should be able to get into the lower 80s,
provided there is enough of a break between the two rounds of
storms. With convective complications, this is a medium-
confidence temperature forecast at best.

This post has been edited by snowlover2: Jul 20 2018, 03:18 AM
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NWOhioChaser
post Jul 20 2018, 06:03 AM
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Let's see if OH/MI can Dodge crapvection this morning...
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RobB
post Jul 20 2018, 07:27 AM
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I rather have it fall as a steady long lasting rain, I can't know the fact that my very dry lawn saw a quick .71 inches of rain from round one this morning!

Need more!
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FireworkWX03
post Jul 20 2018, 07:33 AM
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QUOTE
.NEAR TERM /THROUGH SATURDAY/...
It could be an interesting day. The new guidance continues to
hint at two possible rounds of showers and thunderstorms today.
The models show an area of convection moving into the area this
morning along an advancing warm front. Already seeing new
development over eastern IN. This activity should lift slowly
northeast across the rest of the area today. A gradual
weakening is expected through midday with an increase in
intensity possible later in the afternoon as the convection
approaches the PA border. By early afternoon surface dew points
will have surged into the middle and upper 60s in the west and
south setting the stage for a possible second round of storms
later this afternoon and evening. Confidence isn`t quite as high
for this convection. Best guess is that a line of storms will
develop upstream in an area of better shear and instability and
then advect east into the local area. Will probably see a broken
line of storms arrive early in the evening. It still appears
best chances for severe weather will be west and southwest of
the area so am a little surprised the slight risk area was
expanded across the western half of the area. The storm
intensity this afternoon will depend on earlier convection and
how much debris cloud lingers over the region. This situation
will need to be monitored today.


CLE sort of biting sort of not biting, but I'd definitely be watching if I was in the Toledo/Findlay area as ILN has hinted at. Latest HRRR runs haven't been as bullish on the warm front in the afternoon but then again the HRRR is not reflecting reality at present as there is currently a solid line of storms up through APX. blink.gif Let's see what the 12Z run does.
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Snow____
post Jul 20 2018, 07:38 AM
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QUOTE(RobB @ Jul 20 2018, 08:27 AM) *
I rather have it fall as a steady long lasting rain, I can't know the fact that my very dry lawn saw a quick .71 inches of rain from round one this morning!

Need more!

Agreed. First time Ive seen rain in weeks honestly. Just had a very light shower or 2 over this the past few weeks. This will be nice for sure.


--------------------
Accuweather please give us our own Midwest area forecaster/video blogger
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