Hail and Damaging Winds in Ohio, August 18, 2019

Area Forecast Discussion
National Weather Service Northern Indiana
1249 AM EDT Sun Aug 18 2019

.SYNOPSIS...
Issued at 130 PM EDT Sat Aug 17 2019

Chances for showers and thunderstorms will continue this evening
through Sunday. Then afternoon chances for showers and
thunderstorms will occur on Monday and Tuesday ahead of a cold
frontal passage Wednesday night. Temperatures and humidity levels
will be on the rise for many areas with highs potentially reaching
the upper 80s to near 90 degrees and heat indices rising into
the lower 90s Sunday through Tuesday.

&&

.SHORT TERM...(This Afternoon through Sunday)
Issued at 228 PM EDT Sat Aug 17 2019

Chances for showers and thunderstorms will continue this afternoon
through Sunday as a series convectively enhanced impulses track east
in quasi-zonal westerly flow aloft. A somewhat diffuse low level
front and instability axis from the Lower Great Lakes back west into
IA/NE will also aid in these periodic rain chances.

For this afternoon and evening, a leftover MCV and weak front will
likely combine to produce isolated to scattered convection. SPC
continues to highlight the area in a low risk for isolated severe
storms (wind and hail) given decent flow aloft and the potential
for some enhancement from the MCV. Cloud debris with MCS remnants
and slightly warmer temps aloft will likely keep MLCAPE values in
check however (~1000 j/kg)...hence the very low probability.

The nocturnal low level jet will ramp up tonight into the above
mentioned frontal boundary across the Upper Midwest/Corn Belt, while
additional shortwave energy ripples east from the High Plains.
These features should force another convective cluster that will
traverse the Lower Great Lakes region Sunday morning. The
overnight period should be mainly dry, though hard to completely
rule out chances for a few showers/storms as LLJ increases
convergence and warm advection into the lingering moisture axis.
The upstream MCS then becomes the primary concern for Sunday
morning and early Sunday afternoon with propagation vectors and
orientation of the instability gradient favoring an eastward track
into the Lower Great Lakes, though likely in a weakening/slowing
state. Highest chances for a round of rain/embedded thunder are
across our MI zones (40-60%), trending down to around 20-30
percent across the southern half of the forecast area. Locally
heavy rain appears to be the primary threat, though an isolated
strong storm (wind and hail) cannot be ruled out.

Renewed convection will then be possible Sunday afternoon and
evening along the trailing composite outflow. MLCAPE values are
progged to reach 1500-2000 j/kg along and south of this boundary
with deep layer shear near 30 knots. This could once again provide
the threat for an isolated strong-severe thunderstorm, though
confidence on positioning/track of key features remains low (hence
the marginal SPC risk and low-mid chance PoPs). Convection and
cloud debris will determine how warm and muggy it gets otherwise
tomorrow.

&&

.LONG TERM...(Sunday Night through Saturday)
Issued at 227 PM EDT Sat Aug 17 2019

West-northwest flow regime will continue Monday through Wednesday
resulting in periodic low chances for showers/storms as several weak
disturbances ripple through and a frontal boundary oscillates in
the vicinity. Temperatures will generally average near seasonal
norms.

A negative height anomaly looks to release southeast into Ontario
and Quebec for the second half of the week. This process will
finally force a cold front through the local area with Thursday
through Saturday dry and cool for late August.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1248 AM EDT Sun Aug 18 2019

Challenging TAF period for roughly the first 12 or so hours as
multiple chances for showers/storms potentially evolve. The first
round may impact KFWA as a line of storms was expanding in
response to increasing low level jet and approaching wave.
The bulk of the activity appears to remain south of KFWA, but will
be close due to either NE propagation of current storms or
potential for new development ahead of it. Will keep shower/vcts
mention for now. Brief drops in vsby to MVFR would be possible if
airport is directly impacted.

After 10Z models are varying on potential for even greater
coverage of showers/storms along US-24 corridor and then working
north through the remainder of the night into Sun AM. Yet another,
possible more impactful scenario that will have to be watched for
both sites is upstream well established squall line that was
trending ESE. While models generally keep this feature away till
closer to 17Z extrapolation of current line suggests arrival into
KSBN possibly 13-14Z and then racing ESE from there to impact KFWA
an hour or 2 later. All these solutions make for what will be an
evolving TAF forecast. Will focus on first 6 hours and then keep
things rather broadbrushed after 12Z with either amendments or
changes likely by 12Z issuance.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

SYNOPSIS...Roller
SHORT TERM...Steinwedel
LONG TERM...Steinwedel
AVIATION...Fisher

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Hazardous Weather Outlook...UPDATED
National Weather Service Northern Indiana
235 PM EDT Sat Aug 17 2019

INZ003>009-012>018-020-022>027-032>034-MIZ077>081-OHZ001-002-004-005-
015-016-024-025-181845-
La Porte-St. Joseph IN-Elkhart-Lagrange-Steuben-Noble-De Kalb-Starke-
Pulaski-Marshall-Fulton IN-Kosciusko-Whitley-Allen IN-White-Cass IN-
Miami-Wabash-Huntington-Wells-Adams-Grant-Blackford-Jay-Berrien-
Cass MI-St. Joseph MI-Branch-Hillsdale-Williams-Fulton OH-Defiance-
Henry-Paulding-Putnam-Van Wert-Allen OH-
235 PM EDT Sat Aug 17 2019 /135 PM CDT Sat Aug 17 2019/

This Hazardous Weather Outlook is for northern Indiana, southwest
Michigan and northwest Ohio.

.DAY ONE...This afternoon and tonight.

Isolated to scattered thunderstorms are expected this afternoon into
tonight. A strong storm capable of producing gusty winds, hail and
locally heavy rainfall is possible.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Thunderstorms are possible Sunday through Tuesday. A strong storm
capable of gusty winds and locally heavy rainfall can't be ruled out
on Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

LMZ043-046-181845-
New Buffalo MI to St Joseph MI-Michigan City IN to New Buffalo MI-
235 PM EDT Sat Aug 17 2019

This Hazardous Weather Outlook is for The Nearshore Waters of
Southeastern Lake Michigan.

.DAY ONE...This afternoon and tonight.

There is a chance this afternoon into tonight.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance for thunderstorms at times between Sunday and
Tuesday