Special Weather Statement, NWS Wilmington, OH

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
409 PM EDT Fri Apr 9 2021

.SYNOPSIS...
A few showers and isolated thunderstorms will push through the
region the afternoon as an upper level low pressure system lifts
northeast across the Great Lakes. Showers will diminish
tonight, but another upper level disturbance moving into the
region will bring a better chance for showers and thunderstorms
through the day on Saturday.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
With current temperature rising to the upper 70s, instability
has increased and seeing activity along the Ohio and Indiana
border developing in an area of marginal MLCAPE of 500-1000
J/KG.

With DCAPE values approaching 1000 J/Kg combined with decent
low level wind fields, will have to monitor for isolated
stronger gusts, especially with the dry air above about 700mb.
As this band of energy wrapping around the upper low over NE WI
continues to push ENE through the remainder of the evening,
associated gusty wind threat diminishes greatly, though will
diminish through the remainder of the evening as the upper low
continues to progress away from the region.

Overnight will be a relative lull in activity as the first low
pulls off to the NNE, while increased low level moisture ahead
of a second upper low and associated shortwave will bring an
increased chance of showers toward daybreak in the eastern IN
and areas of KY along and west of I-71. Lows in the lower to mid
50s.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A much more widespread chance of showers and some scattered
thunderstorms across the region with the ascent of another upper
low and associated shortwave lifting out of the lower
Mississippi valley. With ML CAPE values again in the 500-1000
J/Kg range and a potent low level wind field, storms again in
the afternoon could have the potential to become strong to
isolated severe.

With this system lifing fairly quickly through the region,
another dry slot will work into the region Saturday night as the
region starts out just ahead of the closed upper low and then a
lull as the low moves through the NW portion of the forecast
area. Temperatures will drop to near 50 ahead of the low, with
mid to upper 40s in the west.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Forecast begins in the cold pool wrap-around moisture and scattered
shower activity Sunday that will cross east across the region.
Southernmost extent of these showers will be limited to the Ohio
River and earlier in the day. As the day progresses, the chances
will remain best along and north of the I-70 corridor closest to the
cold air aloft.

Any showers will end relatively early in the evening, possibly
before nightfall as the heating will most definitely be responsible
for almost half of the lifting producing these showers. Dry
conditions will be found in the region until Monday night when
shortwave energy races east. This was in question yesterday and
remains in question today as to whether the shortwave and its timing
can be forecast accurately, and if it will be strong enough on its
own to spark a round of showers. Attm, it is crossing during a
nocturnal minimum which is garnering different sensible weather
solutions from the models available at this time. GFS is over-
producing, Euro is under-producing, and Canadian may be the best
with an evening shot interacting with what energy would be left from
daytime heating. Given the continued timing differences in the H5
s/w, continue to leave chances out but think that one more day would
better resolve the when, and then models would also have a
subsequently better handle on what would be driving it.

Models are overly-generous painting low chance ~20% probs in from
mid-week onward, but knowing that this does not make it to the
worded forecasts did not have me change to go with a drier thinking
right now. NBM should trend drier than is currently showing us for
the late periods in the forecast.

Sunday will feel cool but be near seasonal normals within a few
degrees of 60. Overnight, Mon, and the next night will be a little
above normal and then readings for the region will cool back to
climo for the remainder of the forecast.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
Gusty winds 25 to 30s kts expected this afternoon in the tight
pressure gradient before diminishing to less than 10 kts with
the loss of daytime mixing. Still very dry in the low levels and
not a lot of potential for deeper moisture, so the moisture that
does exist is producing only spotty VFR showers. While a stray
shower will be possible, should be mainly at KDAY and spotty
enough to be handled via VCSH. VFR conditions through the period
except for especially KLUK/KCVG and possibly KDAY in the 15-18z
period where deeper moisture would bring MVFR ceilings.

OUTLOOK...MVFR ceilings possible Saturday afternoon into
Saturday night, with gusty winds possible Saturday afternoon and Sunday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

SYNOPSIS...JDR
NEAR TERM...JDR
SHORT TERM...JDR
LONG TERM...Franks
AVIATION...JDR

Hazardous Weather Outlook
National Weather Service Wilmington OH
434 AM EDT Fri Apr 9 2021

INZ050-058-059-066-073>075-080-KYZ089>091-OHZ026-034-035-042>044-
051>053-060>062-070-071-077-101100-
Wayne-Fayette IN-Union IN-Franklin IN-Ripley-Dearborn-Ohio-
Switzerland-Carroll-Gallatin-Boone-Hardin-Mercer-Auglaize-Darke-
Shelby-Logan-Miami-Champaign-Clark-Preble-Montgomery-Greene-Butler-
Warren-Hamilton-
434 AM EDT Fri Apr 9 2021

This Hazardous Weather Outlook is for East Central Indiana,
Southeast Indiana, Northern Kentucky, Southwest Ohio and West
Central Ohio.

.DAY ONE...Today and tonight.

Isolated showers and thunderstorms will be possible later this
afternoon into early evening. A few storms may become strong to
severe with damaging wind being the primary threat.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Showers and chance of thunderstorms will overspread the region on
Saturday. A few strong to severe storms will be possible in the
afternoon and early evening hours. Damaging wind will be the primary
threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

KYZ092>100-OHZ045-046-054>056-063>065-072>074-078>082-088-101100-
Kenton-Campbell-Owen-Grant-Pendleton-Bracken-Robertson-Mason-Lewis-
Union OH-Delaware-Madison-Franklin OH-Licking-Fayette OH-Pickaway-
Fairfield-Clinton-Ross-Hocking-Clermont-Brown-Highland-Adams-Pike-
Scioto-
434 AM EDT Fri Apr 9 2021

This Hazardous Weather Outlook is for Northeast Kentucky, Northern
Kentucky, Central Ohio, South Central Ohio and Southwest Ohio.

.DAY ONE...Today and tonight.

There is a low probability for widespread hazardous weather.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Showers and chance of thunderstorms will overspread the region on
Saturday. A few strong to severe storms will be possible in the
afternoon and early evening hours. Damaging wind will be the primary
threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Special Weather Statement
National Weather Service Wilmington OH
429 PM EDT Fri Apr 9 2021

OHZ043-051>053-061-092100-
Champaign OH-Montgomery OH-Shelby OH-Clark OH-Miami OH-
429 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN SHELBY...WESTERN
CHAMPAIGN...NORTHWESTERN CLARK...NORTHERN MONTGOMERY AND MIAMI
COUNTIES UNTIL 500 PM EDT...

At 428 PM EDT, radar indicated a strong thunderstorm over Tipp City,
moving northeast at 35 mph.

STORM HAZARDS INCLUDE...
Winds to 50 mph...

Locations impacted include...
Dayton, Springfield, Huber Heights, Troy, Trotwood, Piqua, Vandalia,
Englewood, Urbana, Tipp City, New Carlisle, West Milton, Northridge,
St. Paris, Pleasant Hill, Brown, Clayton, Union, Brookville and
Phillipsburg.

This includes the following Interstates...
 I-70 in Ohio between mile markers 20 and 39.
 I-75 in Ohio between mile markers 60 and 81.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 4027 8392 3999 8362 3976 8447 3992 8444
      3992 8443 4004 8443 4027 8396
TIME...MOT...LOC 2028Z 238DEG 32KT 3997 8421

Hickman

Special Weather Statement
National Weather Service Wilmington OH
443 PM EDT Fri Apr 9 2021

OHZ044-045-052-092115-
Champaign OH-Logan OH-Union OH-
443 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN CHAMPAIGN...SOUTHERN
LOGAN COUNTIES IN WEST CENTRAL OHIO AND WESTERN UNION COUNTIES IN
CENTRAL OHIO UNTIL 515 PM EDT...

At 443 PM EDT, radar indicated a strong thunderstorm near De Graff,
moving east at 50 mph.

STORM HAZARDS INCLUDE...
Winds to 50 mph...
Pea size hail...

Locations impacted include...
Marysville, Bellefontaine, Urbana, West Liberty, North Lewisburg, De
Graff, West Mansfield, Quincy, Woodstock, Valley Hi, Zanesfield,
Cable, Raymond, Westville, New Jerusalem, Broadway, Millerstown,
Pottersburg, Kennard and East Liberty.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 4024 8327 4008 8391 4031 8401 4032 8400
      4034 8400 4051 8344 4050 8343
TIME...MOT...LOC 2043Z 249DEG 45KT 4026 8388

Hickman

Special Weather Statement
National Weather Service Wilmington OH
452 PM EDT Fri Apr 9 2021

OHZ051>053-092115-
Champaign OH-Clark OH-Miami OH-
452 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT CHAMPAIGN...NORTHERN CLARK AND
SOUTHEASTERN MIAMI COUNTIES UNTIL 515 PM EDT...

At 451 PM EDT, radar indicated a strong thunderstorm near New
Carlisle, moving east at 45 mph.

STORM HAZARDS INCLUDE...
Winds to 50 mph...
Pea size hail...

Locations impacted include...
Springfield, Huber Heights, Troy, Urbana, Tipp City, New Carlisle,
Northridge, St. Paris, Mechanicsburg, Brown, Christiansburg, North
Hampton, Tremont City, Woodstock, Donnelsville, Catawba, Casstown,
Mutual, Cable and Thackery.

This includes I-70 in Ohio between mile markers 63 and 64.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 4018 8350 4015 8350 3998 8352 3995 8353
      3988 8405 3989 8414 4006 8422 4022 8349
TIME...MOT...LOC 2051Z 254DEG 41KT 4000 8397

Hickman

Special Weather Statement
National Weather Service Wilmington OH
459 PM EDT Fri Apr 9 2021

OHZ051-053-061-062-092130-
Montgomery OH-Clark OH-Greene OH-Miami OH-
459 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT CLARK...NORTHERN GREENE...
EASTERN MONTGOMERY AND SOUTHEASTERN MIAMI COUNTIES UNTIL 530 PM
EDT...

At 459 PM EDT, radar indicated a strong thunderstorm over
Wright-Patterson Afb, moving east at 45 mph.

STORM HAZARDS INCLUDE...
Winds to 50 mph...
Pea size hail...

Locations impacted include...
Dayton, Springfield, Kettering, Beavercreek, Huber Heights, Fairborn,
Xenia, Vandalia, Bellbrook, Moraine, New Carlisle, Oakwood, Yellow
Springs, Wright-Patterson Afb, Northridge, Cedarville, Enon, South
Charleston, Wilberforce and Riverside.

This includes the following Interstates...
 I-70 in Ohio between mile markers 31 and 67.
 I-75 in Ohio between mile markers 51 and 63.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 4002 8366 3992 8359 3977 8364 3977 8365
      3974 8365 3963 8419 3988 8425 4002 8373
TIME...MOT...LOC 2059Z 254DEG 41KT 3983 8407

Hickman

Special Weather Statement
National Weather Service Wilmington OH
515 PM EDT Fri Apr 9 2021

OHZ044>046-052>055-092145-
Champaign OH-Delaware OH-Logan OH-Madison OH-Franklin OH-Union OH-
Clark OH-
515 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT EASTERN CHAMPAIGN COUNTY IN WEST
CENTRAL OHIO...NORTHWESTERN FRANKLIN COUNTY IN CENTRAL OHIO...
SOUTHEASTERN LOGAN COUNTY IN WEST CENTRAL OHIO...WESTERN DELAWARE
COUNTY IN CENTRAL OHIO...NORTHEASTERN CLARK COUNTY IN WEST CENTRAL
OHIO...NORTHEASTERN MADISON AND SOUTHERN UNION COUNTIES IN CENTRAL
OHIO UNTIL 545 PM EDT...

At 514 PM EDT, radar indicated a strong thunderstorm near Urbana,
moving east at 45 mph.

STORM HAZARDS INCLUDE...
Winds to 45 mph...

Locations impacted include...
Columbus, Springfield, Dublin, Delaware, Upper Arlington, Hilliard,
Marysville, Worthington, Urbana, Powell, Plain City, Mechanicsburg,
North Lewisburg, New California, Polaris, Choctaw Lake, Harmony,
Radnor, Milford Center and Shawnee Hills.

This includes the following Interstates...
 I-70 in Ohio between mile markers 62 and 65.
 I-71 in Ohio between mile markers 116 and 120.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 3991 8375 4016 8386 4042 8316 4031 8302
      4007 8296
TIME...MOT...LOC 2114Z 248DEG 37KT 4005 8371

Hickman

Special Weather Statement
National Weather Service Wilmington OH
524 PM EDT Fri Apr 9 2021

OHZ052>054-062-092200-
Champaign OH-Madison OH-Clark OH-Greene OH-
524 PM EDT Fri Apr 9 2021

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN CHAMPAIGN...
CLARK...NORTHEASTERN GREENE AND MADISON COUNTIES UNTIL 600 PM EDT...

At 524 PM EDT, radar indicated a strong thunderstorm near
Springfield, moving east at 45 mph.

STORM HAZARDS INCLUDE...
Winds to 50 mph...

Locations impacted include...
Springfield, Fairborn, Xenia, London, New Carlisle, Yellow Springs,
West Jefferson, Cedarville, Enon, South Charleston, Choctaw Lake,
Wilberforce, Harmony, Lisbon, Brighton, Lafayette, South Vienna,
South Solon, Donnelsville and Catawba.

This includes I-70 in Ohio between mile markers 45 and 83.

Residents in these areas should remain alert. If this storm becomes
stronger, then a warning may be needed.

To report hazardous weather conditions, go to our website at
weather.gov/iln and submit your report via social media, when you can
do so safely.

LAT...LON 3998 8330 3979 8328 3966 8391 3994 8403
      4009 8344
TIME...MOT...LOC 2124Z 248DEG 37KT 3985 8378

Hickman