River Flood Warning 96, NWS Indianapolis, IN

Area Forecast Discussion
National Weather Service Indianapolis IN
938 PM EDT Tue Mar 22 2022

.Forecast Update...
Issued at 938 PM EDT Tue Mar 22 2022

Minor adjustments required to the forecast this evening. Higher pops
will shift to the east over the next few hours as the primary rain
band does the same, although precipitation chances will not be
eliminated entirely as additional redevelopment of showers is
possible.

Increased wind gusts later tonight into early Wednesday as a dry
slot moves into the region. Already seeing a few gusts into the 30KT
range upstream and while these appear unlikely to be frequent,
occasional gusts in this range will certainly be possible.

Remainder of forecast is in good shape.

&&

.Short Term...(This evening through Wednesday night)
Issued at 308 PM EDT Tue Mar 22 2022

...Rainy weather through the short term...
...Gusty winds and strong to severe T-storms possible Wednesday PM...

Tonight...

Large upper system seen on H20 imagery over the Plains will inch
eastward tonight as an associated surface low moves into northern
Illinois and drags an occluded front into southwestern parts of
central Indiana overnight. A 60+ knot low level jet will nose into
southern Indiana as it progresses across northeastern Kentucky and
gradually weakens by morning. This will keep precipitable water
around an inch or so this evening, near the max moving average. As
the low level jet moves east and dry slot moves in aloft, the
widespread showers will become more scattered over western locales
overnight and toward morning. Instability progs hint at very weak
instability this evening, but too low to put thunder in.

Wednesday...

Thunderstorms will be the main concern for Wednesday and during the
afternoon and early evening as a 130+ knot upper jet moves into the
Tennessee and Ohio Valleys which will place central Indiana in the
left front exit region. In addition, the dry slot will allow for
strong diurnal heating which will result in large low level lapse
rates. That combined with cold air aloft will support surface based
CAPES to 500 J/KG during the afternoon and early evening as the
front moves through resulting in synoptic lift. This should allow
strong to possibly severe thunderstorms and in fact, the Storm
Prediction Center has places northeast parts of central Indiana in a
Slight Risk for severe storms. With the cold air aloft, large hail
and damaging winds will be the main severe threats. Heavy rain will
not be a big threat with the dry air aloft bringing in much lower
precipitable water.

Look for afternoon highs in the lower to middle 60s if the sun came
come out long enough.

Wednesday Night...

Shower chances will linger into Wednesday night as the expansive
upper trough stretches out from the eastern Great Lakes to eastern
Texas. However, temperatures, will be colder, in the wake of the
occluded front, with overnight lows in the lower 40s.

Additional storm total rainfall will be a half an inch to near an
inch and a half with the highest amounts expected over the Wabash
Valley. This will result in continued and or renewed flooding over
area rivers and some flooding of low lying areas.

&&

.Long Term...(Thursday through Tuesday)
Issued at 308 PM EDT Tue Mar 22 2022

Thursday-Friday night will feature roughly the second half of the
highly-amplified long wave trough's presence as it slowly but
steadily spins from the Mid-West to southeastern Canada.  Neither
heavy rain nor thunderstorms are expected through the late week as
brisk westerly winds continue to advect air from the chilly trough
axis...bringing theta-e values too low to produce any appreciable
surface-based lift despite the potential of the cold core aloft.
Instead scattered drizzle and light rain can be expected under
mostly cloudy skies.  Temperatures will be overall slightly below
normal courtesy of afternoon readings only peaking near 50F.

Saturday-Monday will find the upper-level pattern morphing over
Indiana from deep, stacked trough to a seasonably strong northwest
flow with a couple embedded short waves.  The main feature will now
be a broad surface ridge extending from the Northwest Territories to
the Gulf of Mexico, sliding eastward into the Mid-West...while the
passing moisture-starved short waves maintain a cool flow from
Canada while providing variable clouds and generally dry conditions.
Below normal temperatures Saturday are expected to moderate slightly
early next week as the gradient of heights and H850 temperatures
slowly retreat to the north.

The long tern will end as a new system starts to take shape over the
central High Plains, with so far good model agreement in the
eastward extension of its warm frontal zone...and therefore chance
POPs...into the Mid-West by mid-week.  Temperatures will trend to
slightly above normal by the end of the long term.

&&

.Aviation...(00Z TAF Issuance)
Issued at 707 PM EDT Tue Mar 22 2022

IMPACTS:

* Low Level Wind Shear at times through the night.

* Occasional MVFR visibilities through the evening in rain with
  ceilings gradually deteriorating to MVFR and then IFR by daybreak
  Wednesday.

* Surface wind gusts increasing to the low 20KT range later this
  evening as winds gradually veer from the east to the south
  overnight.

DISCUSSION:

Widespread rain and increasingly poor flying conditions expected
overnight ahead of a broad low pressure system moving into the
Midwest. Ceilings are predominantly VFR now but will deteriorate to
MVFR overnight and finally IFR by daybreak Wednesday, before some
potential improvement back to MVFR late in the period. Visibilities
will likely fluctuate between VFR and MVFR in rain. While occasional
rumbles of embedded thunder are possible in the rain, chances of
impacts to any one site are too low for explicit inclusion in the
TAFs.

Strong winds just off the surface will promote some gustiness as
well as some low level wind shear at times overnight. Surface winds
will gradually veer from the east to the south through the period.

&&

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

&&

Update...Nield
Short Term...MK
Long Term...AM
Aviation...Nield

Hazardous Weather Outlook...UPDATED
National Weather Service Indianapolis IN
315 PM EDT Tue Mar 22 2022

INZ021-029>031-036>042-045>049-053>057-062>065-070>072-231000-
Carroll-Tippecanoe-Clinton-Howard-Montgomery-Boone-Tipton-Hamilton-
Madison-Delaware-Randolph-Putnam-Hendricks-Marion-Hancock-Henry-Owen-
Morgan-Johnson-Shelby-Rush-Monroe-Brown-Bartholomew-Decatur-Lawrence-
Jackson-Jennings-
Including the cities of Delphi, Flora, Lafayette, West Lafayette,
Frankfort, Kokomo, Crawfordsville, Lebanon, Zionsville, Tipton,
Fishers, Carmel, Noblesville, Anderson, Muncie, Winchester,
Union City, Farmland, Parker City, Greencastle, Plainfield,
Brownsburg, Danville, Indianapolis, Greenfield, New Castle, Spencer,
Gosport, Martinsville, Mooresville, Greenwood, Franklin,
Shelbyville, Rushville, Bloomington, Nashville, Columbus,
Greensburg, Bedford, Mitchell, Seymour, and North Vernon
315 PM EDT Tue Mar 22 2022

This hazardous weather outlook is for central Indiana.

.DAY ONE...This Afternoon and Tonight.

Moderate to heavy rain is possible at times through Tonight.
This could lead to minor flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

A few strong thunderstorms storms are possible Wednesday morning
and afternoon. Cloud to ground lightning, gusty winds and small
hail will be possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is possible Wednesday afternoon and evening.

&&

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

INZ028-035-043-044-051-052-060-061-067>069-231000-
Warren-Fountain-Vermillion-Parke-Vigo-Clay-Sullivan-Greene-Knox-
Daviess-Martin-
Including the cities of Williamsport, West Lebanon, Attica,
Covington, Veedersburg, Clinton, Fairview Park, Rockville,
Montezuma, Rosedale, Terre Haute, Brazil, Sullivan, Carlisle,
Shelburn, Farmersburg, Linton, Bloomfield, Jasonville, Worthington,
Vincennes, Washington, Loogootee, and Shoals
315 PM EDT Tue Mar 22 2022

This hazardous weather outlook is for central Indiana.

.DAY ONE...This Afternoon and Tonight.

Moderate to heavy rain is possible at times through Tonight. This
could lead to minor flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

A few strong or severe thunderstorms storms are possible Wednesday
afternoon and evening. The main threat severe threats will be large
hail and damaging winds. Cloud to ground lightning will also be
a threat.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is possible Wednesday afternoon and evening.

&&

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