Special Weather Statement, NWS Indianapolis, IN

Area Forecast Discussion
National Weather Service Indianapolis IN
300 PM EDT Mon Jun 28 2021

.Short Term...(This evening through Tuesday night)
Issued at 300 PM EDT Mon Jun 28 2021

Another afternoon with isolated to scattered thunderstorms ongoing
in the stagnant warm and humid airmass in place across the area.
Expect convective activity to continue into the evening then wane
for the most part overnight, although some slight activity may
linger northwest overnight nearer the frontal zone to our north and
west. CAMs suggest most of this activity will remain out of the area
but cannot entirely justify a dry forecast over the entire area.

Looks as though the pattern may finally begin to slowly shift late
tomorrow into tomorrow night as the ridge begins to retreat and
modest height falls begin across the area. Ample instability will be
present across the area, although shear will remain weak, and severe
potential will likely be limited to a few pulse type gusty wind
producers, primarily north nearest the upper level support.

Will have to carry a bit higher pops into the overnight tomorrow
night than in recent nights as the frontal zone makes a closer
approach, but with the loss of daytime heating any storms will be
primarily heavy rain producers with a localized flooding threat at
best.

Temperatures look to remain roughly steady state until the front
gets into the area beyond the short term, and blend largely reflects
this with only some minor tweaks necessary.

&&

.Long Term...(Wednesday through Monday)
Issued at 300 PM EDT Mon Jun 28 2021

An upper level trough will move into the area through the end of the
week. At the surface, a front will slowly move through the area
during the same time frame. Plentiful moisture will continue along
and ahead of the surface front, with precipitable water values of
1.5 to 2 inches. The combination of forcing from the trough and
front and the moisture will lead to high PoPs at times Wednesday and
Thursday. Locally heavy rain will remain a threat then.

Questions then remain with the potential development of an upper low
for the holiday weekend. GFS and Canadian both develop an upper low,
but the GFS is much farther west with it. Even the GEFS mean briefly
develops an upper low over the area. Meanwhile the ECMWF is more
progressive and moves the upper trough east of the area.

Given the high uncertainty in the development of the pattern, will
just keep some low PoPs in each day through the holiday weekend.
PoPs will be most widespread in the afternoon hours.

With the passage of the cold front and with an upper trough/upper
low around, temperatures will be below normal for much of the period.

&&

.Aviation...(18Z TAF Issuance)
Issued at 126 PM EDT Mon Jun 28 2021

IMPACTS:

* Isolated to scattered thunderstorms through the evening.

* Winds 10-12KT from 200-210 degrees. Weaker after 01Z.

DISCUSSION: Convective temperatures have been reached and isolated
to scattered thunderstorm development is underway across much of the
area. Will carry a VCTS mention at all sites through 01Z as the bulk
of activity today should be diurnally driven again, and timing
impact at any one site is prohibitively difficult.

Winds will be from 200-210 degrees throughout the afternoon into the
early evening, with sustained winds around 10-12KT. A few gusts are
possible, but should be sporadic and weak enough to exclude mention.
Winds will weaken in typical diurnal fashion this evening.

&&

.IND WATCHES/WARNINGS/ADVISORIES...None.

&&

Short Term...Nield
Long Term...50
Aviation...Nield

Hazardous Weather Outlook
National Weather Service Indianapolis IN
327 PM EDT Mon Jun 28 2021

INZ021-028>031-035>049-051>057-060>065-067>072-291930-
Carroll-Warren-Tippecanoe-Clinton-Howard-Fountain-Montgomery-Boone-
Tipton-Hamilton-Madison-Delaware-Randolph-Vermillion-Parke-Putnam-
Hendricks-Marion-Hancock-Henry-Vigo-Clay-Owen-Morgan-Johnson-Shelby-
Rush-Sullivan-Greene-Monroe-Brown-Bartholomew-Decatur-Knox-Daviess-
Martin-Lawrence-Jackson-Jennings-
Including the cities of Delphi, Flora, Williamsport, West Lebanon,
Lafayette, West Lafayette, Frankfort, Kokomo, Attica, Covington,
Veedersburg, Crawfordsville, Lebanon, Zionsville, Tipton, Fishers,
Carmel, Noblesville, Anderson, Muncie, Winchester, Clinton, Newport,
Rockville, Greencastle, Plainfield, Brownsburg, Danville,
Indianapolis, Greenfield, New Castle, Terre Haute, Brazil,
Clay City, Spencer, Martinsville, Mooresville, Greenwood, Franklin,
Shelbyville, Rushville, Sullivan, Linton, Bloomfield, Bloomington,
Nashville, Columbus, Greensburg, Vincennes, Washington, Loogootee,
Shoals, Bedford, Mitchell, Seymour, Brownstown, and North Vernon
327 PM EDT Mon Jun 28 2021

This hazardous weather outlook is for central Indiana.

.DAY ONE...This Afternoon and Tonight.

Isolated to scattered thunderstorms can be expected through the
evening hours. Heavy rain and localized flooding will be the primary
threats with a few of the stronger storms producing gusty winds.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Periodic chances for showers and thunderstorms will continue through
much of the rest of the week with the greatest coverage of storms
coming most likely on Wednesday and Thursday. Storms will produce
heavy rainfall and may be strong at times with gusty winds.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.

&&

More information, along with other weather, hydrological and climate
information can be found at http://weather.gov/ind

Special Weather Statement
National Weather Service Indianapolis IN
427 PM EDT Mon Jun 28 2021

INZ055-063-064-282100-
Johnson-Brown-Bartholomew-
427 PM EDT Mon Jun 28 2021

...A STRONG THUNDERSTORM WILL AFFECT SOUTHERN JOHNSON...NORTHEASTERN
BROWN AND NORTHWESTERN BARTHOLOMEW COUNTIES...

At 427 PM EDT, a strong thunderstorm was located near Nashville, or
15 miles west of Columbus, moving north at 20 mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Nashville, Edinburgh, Princes Lakes, Trafalgar, Peoga and
Spearsville.

This includes Interstate 65 between mile markers 84 and 85.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 3923 8628 3949 8619 3942 8595 3935 8595
      3917 8608
TIME...MOT...LOC 2027Z 200DEG 17KT 3929 8619

CP

Special Weather Statement
National Weather Service Indianapolis IN
500 PM EDT Mon Jun 28 2021

INZ055-282130-
Johnson-
500 PM EDT Mon Jun 28 2021

...A STRONG THUNDERSTORM WILL AFFECT JOHNSON COUNTY...

At 500 PM EDT, a strong thunderstorm was located near Franklin, or 18
miles west of Shelbyville, moving north at 25 mph.

Wind gusts of 50 to 55 mph are possible with this storm.

Locations impacted include...
Greenwood, Franklin, New Whiteland, Whiteland, Bargersville, Princes
Lakes and Trafalgar.

This includes Interstate 65 between mile markers 85 and 100.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3935 8600 3934 8607 3938 8623 3964 8616
      3964 8613 3962 8595 3948 8595
TIME...MOT...LOC 2100Z 189DEG 20KT 3945 8610

CP

Special Weather Statement
National Weather Service Indianapolis IN
521 PM EDT Mon Jun 28 2021

INZ047-282145-
Marion-
521 PM EDT Mon Jun 28 2021

...A STRONG THUNDERSTORM WILL AFFECT WESTERN MARION COUNTY...

At 520 PM EDT, a strong thunderstorm was located near Speedway, or
near Indianapolis, moving northeast at 20 mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Indianapolis, Fishers, Speedway, Meridian Hills, Rocky Ripple,
Williams Creek, Wynnedale, Spring Hill, Crows Nest, North Crows Nest,
Monument Circle, Castleton, Indiana State Fairgrounds and Broad
Ripple.

This includes the following highways...
 Interstate 65 between mile markers 113 and 123.
 Interstate 70 between mile markers 73 and 79.
 Interstate 74 between mile markers 72 and 73.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3969 8621 3974 8633 3992 8627 3993 8603
TIME...MOT...LOC 2120Z 203DEG 16KT 3975 8627

CP