The entire state of Indiana has the possibility of seeing severe weather tomorrow so pay close attention and keep your weather radios turned on. Here are the details from the National Weather Service:
Short Term...(Today through Wednesday)
Issued at 259 AM EDT Tue Apr 12 2022
...SEVERE THUNDERSTORM THREAT WEDNESDAY INTO WEDNESDAY NIGHT...
BOTTOM LINE UP FRONT
* A line of strong to severe storms will move through at some point
later Wednesday afternoon into Wednesday evening.
* Damaging winds and a few tornadoes are the primary severe threats,
along with heavy rain.
* Some uncertainty remains in timing and extent of severe potential.
Today...
Early this morning, a front had stalled out to the south of central
Indiana. A dewpoint gradient was across the area, with dewpoints
around 40 north to the mid 50s far south. Most of the area was dry.
The front will return north today as a warm front, with southwest
flow developing aloft ahead of an upper wave. With the upper wave
still well upstream during the day, there won`t be much upper
support for the warm front. There will be some isentropic lift
though with a slow increase in southwest flow aloft during the day.
Thus do not expect much if any convection to develop today. If it
does, it should be in the southern forecast area. Will have some low
PoPs there today, but with low confidence. Enough instability may
build in the far southwestern forecast area for a conditional threat
of a strong thunderstorm, but again confidence is quite low.
Am expecting a good amount of clouds around with moist low level air
moving in behind the warm front.
Tonight...
Any convection from this afternoon should end by early evening. A
lull will then occur for the remainder of the evening. Overnight, an
upper wave will approach from the southwest. The low level jet will
increase to 50kt or more by the overnight. Plentiful moisture will
be around with precipitable water values over an inch. With this
moisture and forcing, will go likely or higher PoPs across the
southwest forecast area by 12Z. Much of the instability will be
aloft.
Do not expect much of a severe threat overnight, but a strong storm
with gusty winds is possible in the southwest.
Wednesday (before the main line of storms)...
Convection from the initial upper wave will still be moving northeast
through the area Wednesday morning. Not expecting severe weather
with this given limited instability.
Additional convection will develop during the day in the warm and
moist atmosphere (even surface dewpoints may get into the 60s), with
some lift ahead of an approaching large upper trough. Expect rain at
times during the day. Will go high PoPs all areas given this and the
morning rain. Depending on how much instability can build between
rounds of rain, a strong storm is possible.
Wednesday into Wednesday night (the main line of storms)...
The upper trough will become negatively tilted by Wednesday evening.
A strong cold front will approach the area from the west later
Wednesday afternoon and move through before 06Z Thursday. Very
strong shear will be across the area with 0-3km bulk shear of 50kt
possible. Instability will be modest, but the high shear should
overcome any limits from instability. Good forcing is expected ahead
of the approaching cold front. Thus, a line of strong and severe
thunderstorms is expected to move through central Indiana.
There remains some uncertainty on the timing of the main line of
convection with some model runs bringing the line in a few hours
before 00Z and others around 00Z. Also, even though the shear will
help overcome instability, there is some concern that the previous
rain during the day could result in some of the convection becoming
more elevated across parts of the area. However, given the
potential, will continue to play up the severe threat all areas, and
will have a broad time of afternoon into evening to account for that
uncertainty.
Heavy rain will also be a threat Wednesday into Wednesday night with
potential for repeated rounds of convection and high moisture
content of the atmosphere.
