Severe Thunderstorm Warning 8, NWS Indianapolis, IN

537 
WWUS53 KIND 280822
SVSIND

Severe Weather Statement
National Weather Service Indianapolis IN
322 AM EST Wed Feb 28 2024

INC065-139-145-280845-
/O.CON.KIND.SV.W.0008.000000T0000Z-240228T0845Z/
Shelby IN-Rush IN-Henry IN-
322 AM EST Wed Feb 28 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM EST
FOR EAST CENTRAL SHELBY...CENTRAL RUSH AND SOUTHEASTERN HENRY
COUNTIES...

At 322 AM EST, severe thunderstorms were located along a line
extending from 6 miles north of Hagerstown to 6 miles northwest of
Connersville to near Shelbyville, moving east at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Rushville, Glenwood, and Manilla around 325 AM EST.

This includes Interstate 70 between mile markers 132 and 133.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 600 AM EST for central and
east central Indiana.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3987 8522 3979 8522 3979 8530 3961 8530
      3956 8544 3956 8575 3967 8555 3971 8536
      3988 8524 4000 8520 3988 8520
TIME...MOT...LOC 0822Z 259DEG 47KT 4000 8512 3971 8524 3954 8570 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

White

Area Forecast Discussion
National Weather Service Indianapolis IN
252 AM EST Wed Feb 28 2024

.Key Messages...

- Strong to possibly severe weather pre-dawn hours
- Windy conditions persist into the afternoon
- Much colder today with wind chills in the teens and 20s
- Moderation this weekend...very mild, rain chances early next week

&&

.Mesoscale Update...
Issued at 111 AM EST Wed Feb 28 2024

A loose complex of storms has now crossed into central Indiana with
the strongest portion of the storm just south of Terre Haute.  There
has been some transient low level rotation which lead to a tornado
warning.  These storms have organized to the point of being able to
tap into better instability in the mid levels but with the narrow
axis of highest near surface shear, they've not been able to truly
organize up to this point.  The environment looks similar across
west central Indiana which should provide at least steady state
conditions with this storm as it tracks up the I-70 corridor.
Elsewhere little has changed in the last hour with the previous
mesoscale discussion below:

Confidence continues to slowly decrease in the severe weather threat
with convection struggling to advance beyond the front and without a
lifting source beyond the frontal convergence, thunderstorms thus
far have generally been elevated to only loosely surface based.
Current observations show the front will be crossing into the far
northwestern counties over the next 15-20 minutes.  Latest soundings
show the inversion is gone but instability continues to gradually
decrease and with the surface winds remaining in the 200-220
direction, low level shear remains a bit lower than earlier
expected.  The ongoing convection along the I-70 corridor remains
near steady state with cloud tops around 25kft and only sporadic
lightning. These storms may be able to become severe, but based on
trends over the last 2 hours, confidence is low.

WoFS continues to highlight the Ohio River being the primary area
for severe convection over the next 3 hours but if convection
continues to struggle to grow even with the surface convergence and
remains elevated near and behind the front, the severe threat will
continue to diminish.

&&

.Short Term...(Today and tonight)
Issued at 251 AM EST Wed Feb 28 2024

Early This Morning...
Pre-convection atmosphere has been struggling due to the persistent
warm nose aloft/inversion limiting the ability for strong vertical
growth to occur. Latest aircraft data has shown this inversion
slowly dissipating over the Indy metro airspace. SFC wind fields
have maintained a uniform setup with no indications of backing
winds. Gradient still exists as mixed layer is still bringing to the
surface gusty winds in excess of 34kts at times. Lapse rates most
concerning are within the mid-lvls still hovering near 8 deg c/km.
This coupled with the upper level jet streak positioned to the west,
it places Central and Southern Indiana in the favored upper level
diffluent zone and encourages low-lvl vertical growth from
convergence. Sfc dewpoints ahead of the boundary continue to be in
the upper 50s, with some speed convergence aiding in some lift. The
convection that has developed early this morning west/southwest of
Indy metro and extending southwest has been along the lee-side of
the frontal boundary, which is evident in the considerable drop with
T/Td value and west/northwest winds.

By daybreak convection should have pushed southeast of Central
Indiana with the frontal passage ushering in much cooler/drier air.
Trough axis quickly nudges east with sharp isallobaric gradient
developing in the hours just after daybreak. The concern here is
that with skies perhaps clearing quickly the ability to easily mix
to the surface a core of 40-45kts. At this time have held off on
issuing a wind advisory as we are expecting just enough filtering to
occur with lingering clouds to inhibit our ability to have a clean
momentum transfer of winds to the sfc. Likely will see an occasional
gust to 35-40mph, but not anticipating a high frequency of this.

Temps will continue to cold air advect with the thermal trough
plunging the sensible layer into the lower 30s by midday. This
coupled with gusty winds will likely produce apparent temps in the
low/mid teens. Which given the prior couple of warm/humid days will
feel like a blast of winter, but fortunately the atmos is rather dry
and the only location to see perhaps some flurries or light snow is
presently looking like a Kokomo to Muncie line and points northeast.

Early Afternoon...Pressure gradient begins to relax by the afternoon
hours with anti-cyclonic flow becoming centered over Missouri. Flow
will remain northwesterly, but expect the gusts to slowly subside to
less than 30mph by late afternoon.

Tonight...The progressive flow to the upper levels will allow the
trough axis to quickly pivot east overnight, with heights beginning
to rise overnight from west to east. This will translate into much
lighter winds and expect mostly clear skies. Temps will radiate into
the lower 20s.

&&

.Long Term...(Thursday through Tuesday)
Issued at 251 AM EST Wed Feb 28 2024

Thursday and Thursday night...

Thursday will feature surface high pressure planted across central
Indiana along with a dry column. The sunny skies will allow
temperatures to recover a few degrees back to normal as compared
with the expected cold temperatures, this afternoon, in the wake of
the strong cold front. The high will drift off to the east Thursday
night allowing for a return to southerly inflow. That and increase
in mid and high clouds ahead of a southern Plains wave will limit
overnight lows to no colder than the middle and upper 20s.

Friday...

The dilemma Friday as how far north showers will get associated with
a southern Plains wave that will quickly move through. The 00Z GFS
and Canadian models are quicker, further north and wet than the 12z
ECMWF. Quick look at the 00z ECMWF shows it is trending towards the
GFS/Canadian combo. After coordination with IWX, decided to stretch
small PoPs as far north as their border per the blend. BUFKIT
soundings, critical thicknesses and Bourgouin technique support a
rain/snow mix to start during the morning.

Tightening surface low pressure gradient in the wake of the high and
well ahead of another surface low pressure system will result in
modestly breezy southerly winds which should help temperatures climb
a few more degrees to normal or slightly above and afternoon highs
mostly in the 40s despite increased cloud cover.

Friday night through Sunday...

Continued southerly flow and a drying column in the wake of the
southern Plains wave will lead to another big warm up with plenty of
sunshine and highs in the upper 50s to lower 60s Saturday and middle
to 60s to perhaps even 70 degrees on Sunday.

Sunday night through Tuesday night...

A warm front will pass through Sunday night followed by a cold front
Monday and another one approaching Tuesday night. Increased moisture
from southerly flow along with the warm advection will bring more
rain chances to the area Sunday night into Monday along with the
continued well above normal temperatures. Slightly cooler
temperatures will follow the first cold front Tuesday. Thickness
pattern suggests the real cold air will not make it this far south,
just beyond the long term.

&&

.Aviation...(06Z TAF Issuance)
Issued at 1244 AM EST Wed Feb 28 2024

Impacts:

- Wind gusts 25 knots or more through much of the period

- Wind shift to the northwest roughly 08-10Z time frame

- Scattered to numerous convection into the aft 07Z thru 10Z

Discussion:

Convection has continued to be struggling to grow in coverage and
intensity early this morning, but there is an area of thunderstorms
trying to develop in southeast Illinois and lifting east. Guidance
has continued to favor a further south path for showers and
thunderstorms, which would favor the southern Indiana airfields. But
the instability leading to more robust thunderstorm activity has
decreased as well.

Low level jet will bring non-convective low level wind shear through
about 08Z. Some of these winds will mix down creating gusts at the
surface with gusts up to 35kts at times.

Strong cold front will move through overnight shifting winds and
increasing gusts. MVFR ceilings will occur behind the front then
skies will scatter out by Wednesday afternoon most sites.

&&

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

Mesoscale...White
Short Term...Beach
Long Term...MK
Aviation...Beach

Hazardous Weather Outlook
National Weather Service Indianapolis IN
352 PM EST Tue Feb 27 2024

INZ021-028>031-035>049-051>057-060>065-067>072-282100-
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-
352 PM EST Tue Feb 27 2024

This Hazardous Weather Outlook is for Central Indiana.

.DAY ONE...Through Tonight.

Weather hazards expected...

  Elevated thunderstorm wind damage risk.
  Elevated large hail risk.
  Elevated tornado risk.
  Elevated lightning risk.

DISCUSSION...

Scattered to numerous thunderstorms will develop across central
Indiana tonight. Some of the storms may be severe, with the main
severe threat from 700 PM to 400 AM. All modes of severe weather
are possible.

Outside of storms, wind gusts around 40 mph are expected this
evening through overnight.

Storm motion would be to the east northeast at around 50 mph.

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

Wind gusts around 40 mph will continue on Wednesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed tonight.

&&

This product in graphical format...along with other weather...
hydrological and climate information...at:

http://www.weather.gov/erh/ghwo?wfo=ind
http://www.weather.gov/ind

WFO IND

Preliminary Local Storm Report
National Weather Service Indianapolis IN
236 AM EST Wed Feb 28 2024

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

0232 AM     Tstm Wnd Gst     1 SW Lawrence           39.86N 86.00W
02/28/2024  E60 MPH          Marion             IN   Public

&&

BH

Preliminary Local Storm Report
National Weather Service Indianapolis IN
248 AM EST Wed Feb 28 2024

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

0235 AM     Hail             Martinsville            39.42N 86.42W
02/28/2024  E0.50 inch       Morgan             IN   Trained Spotter

&&

BH

Preliminary Local Storm Report
National Weather Service Indianapolis IN
252 AM EST Wed Feb 28 2024

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

0250 AM     Hail             Greenfield              39.79N 85.77W
02/28/2024  E0.25 inch       Hancock            IN   Public

            2-inch diameter tree limbs down.

&&

BH

Preliminary Local Storm Report
National Weather Service Indianapolis IN
253 AM EST Wed Feb 28 2024

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

0250 AM     Tstm Wnd Dmg     Greenfield              39.79N 85.77W
02/28/2024                   Hancock            IN   Public

            2-inch diameter tree limbs down.

&&

BH

Preliminary Local Storm Report
National Weather Service Indianapolis IN
302 AM EST Wed Feb 28 2024

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

0257 AM     Hail             Spencer                 39.29N 86.77W
02/28/2024  E0.70 inch       Owen               IN   Amateur Radio

&&

BH

Preliminary Local Storm Report
National Weather Service Indianapolis IN
303 AM EST Wed Feb 28 2024

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

0253 AM     Tstm Wnd Gst     3 ESE Fairland          39.58N 85.80W
02/28/2024  M59 MPH          Shelby             IN   ASOS

&&

BH