Special Weather Statement, NWS Indianapolis, IN

Area Forecast Discussion
National Weather Service Indianapolis IN
1016 AM EDT Sat Jun 19 2021

.Forecast Update...
Issued at 1015 AM EDT Sat Jun 19 2021

Radar loop indicates another convective cluster about to move into
the southwest zones, with short term model data suggesting this
cluster will move through the southwest zones through about 191800Z.

Based on this, and given the earlier heavy rainfall in this area,
will extend parts of the Flash Flood Watch in these area until
191800Z.

Short term model data continue to suggest some convection may
redevelop over parts of the area later this afternoon. Given the
current amount of debris cloud around, convective temperatures may
not be met this afternoon, so not sold on amount of redevelopment
later today. Regardless, this morning's upper air indicates
moderately steep lapse rates and decent deep layer shear remains, so
potential still exists for strong/severe convection.

Decided to lower the highs today a category, based on the current
amount of cloud cover.

&&

.Short Term...(Today through Sunday)
Issued at 239 AM EDT Sat Jun 19 2021

The focus for the remainder of the overnight has shifted to a flash
flood concern as bulk of the current convection related to last
evening's MCS was exiting southeast but more cells were going up
over central Illinois along a northwest to southeast outflow
boundary that extended into southeastern Indiana. Even more ominous
was convection over south central Iowa into west central Illinois.
This area is well underway into becoming an MCS that will track
southeast along the outflow boundary and within the fast northwest
flow aloft and end up moving across central Indiana after 09z per
the convective allowing models. This will lead to even more serious,
potential life threatening flash flooding as convection trains
southeast across south central parts of the forecast area that are
already dealing with flash flooding. Areas of Clay, Owen, Monroe and
Morgan have already seen over 4 inches since last evening per MRMS.
May need to extend the Flash Flood Watch over these areas and pull
some of the northeast counties that have seen little rain and are
not expected today later today.

The bulk of the Iowa MCS should be southeast of the area after 15z.
Confidence is not great on chances of convection the rest of day
with mesoscale boundaries continuing to play a key role on where
storms fire up given lack of obvious forcing mechanisms. That said,
models continue to show strong instability with afternoon CAPEs over
2000 J/kg and 30 plus knot 850 millibar westerly low resulting in
decent low level shear for this time of year. The main front will
remain quasi-stationary over far northern Indiana. This setup
supports at least scattered thunderstorms through this evening with
perhaps a break overnight into Sunday morning.

On Sunday afternoon, more of the same but with upper flow switching
to the west and southwest as a trough digs in over the Plains.
Perturbation ahead of the trough may help things fire up as well.
SPC Day1 and Day2 Outlooks both feature a Marginal Severe Risk over
all of central Indiana, which looks reasonable given the very moist
and unstable atmosphere and sufficient shear. Any storm that dumps
rain over areas that saw a lot earlier tonight, could pose a flood
threat, but expected coverage precludes further headlines at this
time.

&&

.Long Term...(Sunday night through Friday)
Issued at 239 AM EDT Sat Jun 19 2021

Models suggest a cold front will dive southeast across central
Indiana Monday. This front will interact with the stagnant moist and
unstable atmosphere and bring more widespread convection to the area
Monday. Early day timing would discourage severe weather chances.
The convection will be ending from northwest to southeast, and a
much cooler and drier air mass will settle in in the wake of the
front on Tuesday with afternoon highs only in the 70s and dew points
only in the 40s. However, temperatures will be on their way up as
will chances of convection late week as the cool surface high moves
east of the area allowing for a return to southerly and
southwesterly inflow.

&&

.Aviation...(12Z TAF Issuance)
Issued at 633 AM EDT Sat Jun 19 2021

IMPACTS:

- Widespread convection will continue to effect the terminals through 16z.
- Convection will become more scattered after 16z with chances too low
  to include VCTS.
- Winds mostly 190-230 degrees to 10 knots or so and gusts around 20 knots
  16-24z. Gusts higher at times in convection and direction will vary
  at times due to convective outflow.

DISCUSSION: Convective system ongoing across central Indiana will exit
southeast mid morning. Tempo MVFR and worse flying conditions
in the heavier convection. More storms are possible this afternoon and
tonight, but coverage is expected to only be isolated to scattered.

Plenty of uncertainty remains in the specific timing for the sites
themselves.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until 2 PM EDT this afternoon for INZ051>053-
060>065-071-072.

&&

Update...JAS
Short Term...MK
Long Term...MK
Aviation...MK

Hazardous Weather Outlook
National Weather Service Indianapolis IN
334 AM EDT Sat Jun 19 2021

INZ035>037-043>048-051>057-062>065-071-072-201000-
Fountain-Montgomery-Boone-Vermillion-Parke-Putnam-Hendricks-Marion-
Hancock-Vigo-Clay-Owen-Morgan-Johnson-Shelby-Rush-Monroe-Brown-
Bartholomew-Decatur-Jackson-Jennings-
Including the cities of Attica, Covington, Veedersburg,
Crawfordsville, Lebanon, Zionsville, Clinton, Newport, Rockville,
Greencastle, Plainfield, Brownsburg, Danville, Indianapolis,
Greenfield, Terre Haute, Brazil, Clay City, Spencer, Martinsville,
Mooresville, Greenwood, Franklin, Shelbyville, Rushville,
Bloomington, Nashville, Columbus, Greensburg, Seymour, Brownstown,
and North Vernon
334 AM EDT Sat Jun 19 2021

This hazardous weather outlook is for central Indiana.

.DAY ONE...Today and Tonight.

There is Slight Risk for severe thunderstorms today. A few storms
could be strong or severe this morning and a few more could be strong
or severe this afternoon and early evening. The main severe threats
will be damaging winds. Isolated tornadoes and large hail will also
be possible. Frequent lightning is expected. Heavy rainfall and flash
flooding will also be possible, especially this morning.

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

More thunderstorms are possible at times from Sunday through Monday
and again by late next week. There is a Marginal Risk for severe
weather Sunday afternoon and evening. Damaging winds, large hail and
isolated tornadoes are possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will be possible at times this weekend. Spotters
are encouraged to report any flooding issues.

&&

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

INZ021-028>031-038>042-049-060-061-067>070-201000-
Carroll-Warren-Tippecanoe-Clinton-Howard-Tipton-Hamilton-Madison-
Delaware-Randolph-Henry-Sullivan-Greene-Knox-Daviess-Martin-Lawrence-
Including the cities of Delphi, Flora, Williamsport, West Lebanon,
Lafayette, West Lafayette, Frankfort, Kokomo, Tipton, Fishers,
Carmel, Noblesville, Anderson, Muncie, Winchester, New Castle,
Sullivan, Linton, Bloomfield, Vincennes, Washington, Loogootee,
Shoals, Bedford, and Mitchell
334 AM EDT Sat Jun 19 2021

This hazardous weather outlook is for central Indiana.

.DAY ONE...Today and Tonight.

There is Marginal Risk for severe thunderstorms today. A few storms
could be strong or severe this morning and a few more could be strong
or severe this afternoon and early evening. The main severe threats
will be damaging winds. Isolated tornadoes and large hail will also
be possible. Frequent lightning is expected. Heavy rainfall and flash
flooding will also be possible, especially this morning.

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

More thunderstorms are possible at times from Sunday through Monday
and again by late next week. There is a Marginal Risk for severe
weather Sunday afternoon and evening. Damaging winds, large hail and
isolated tornadoes are possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will be possible at times this weekend. Spotters
are encouraged to report any flooding issues.

&&

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
645 AM EDT Sat Jun 19 2021

INZ061>064-067>072-191130-
Daviess-Knox-Brown-Martin-Lawrence-Bartholomew-Greene-Jackson-Monroe-
Jennings-
645 AM EDT Sat Jun 19 2021

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHERN MONROE...
SOUTHERN BROWN...SOUTHERN BARTHOLOMEW...CENTRAL KNOX...MARTIN...
SOUTHEASTERN GREENE...LAWRENCE...JACKSON...JENNINGS AND DAVIESS
COUNTIES...

At 644 AM EDT, radar indicated strong thunderstorms were located
along a line extending from near Nashville to St. Francisville.
Movement was southeast at 50 mph.

Wind gusts up to 50 mph and half inch hail are possible with these
storms.

Locations impacted include...
Columbus, Vincennes, Seymour, Bedford, Washington, North Vernon,
Brownstown, Nashville, Shoals, Vernon, Mitchell, Bicknell, Loogootee,
Crothersville, Odon, Oolitic, Medora, Monroe City, Elizabethtown and
Wheatland.

This includes Interstate 65 between mile markers 37 and 67.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3855 8721 3851 8730 3854 8743 3850 8750
      3855 8766 3865 8760 3924 8614 3903 8544
      3891 8545 3891 8554 3882 8563 3881 8579
      3873 8587 3876 8591 3878 8620 3876 8628
      3869 8631 3869 8668 3853 8668 3849 8695
TIME...MOT...LOC 1044Z 294DEG 43KT 3920 8618 3862 8763

Ryan

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
713 AM EDT SAT JUN 19 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0535 AM     FLASH FLOOD      4 NNW ALAMO             40.03N 87.09W
06/19/2021                   FOUNTAIN           IN   PUBLIC

            INDIANA ROUTE 32 COVERED IN WATER AT
            FOUNTAIN - MONTGOMERY COUNTY LINE.

&&

AGM

Special Weather Statement
National Weather Service Indianapolis IN
1124 AM EDT Sat Jun 19 2021

INZ061-067>070-191630-
Daviess-Knox-Martin-Lawrence-Greene-
1124 AM EDT Sat Jun 19 2021

...WINDS TO 45 MPH AND PEA SIZE HAIL IS POSSIBLE...

At 1122 AM EDT, radar indicated strong thunderstorms were located
along a line extending from 13 miles northwest of Bedford to Mount
Carmel. Movement was southeast at 20 mph.

Winds in excess of 40 mph and pea size hail are possible with these
storms.

Locations impacted include...
Bedford, Washington, Shoals, Mitchell, Loogootee, Odon, Oolitic,
Monroe City, Wheatland, Montgomery, Decker, Crane, Cannelburg,
Alfordsville, West Boggs Lake, Tunnelton, Burns City, Williams, Avoca
and Glendale Fishery.

If outdoors, consider seeking shelter inside a building.

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

LAT...LON 3847 8775 3850 8765 3853 8766 3901 8668
      3892 8628 3872 8631 3869 8643 3869 8668
      3860 8668 3850 8698 3854 8711 3852 8715
      3855 8720 3851 8730 3854 8743 3850 8749
      3850 8758 3845 8760 3846 8766 3842 8774
TIME...MOT...LOC 1522Z 309DEG 18KT 3898 8669 3842 8779

JAS