791
FXUS63 KIWX 061751
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
151 PM EDT Mon May 6 2024

.KEY MESSAGES...

- Severe weather threat for Tuesday afternoon and evening.
  Damaging winds, large hail, and even a few tornadoes are
  possible in any severe storms that develop. Heavy rain and
  minor flooding is possible.

- Severe weather is possible again late Wednesday afternoon into
  the overnight, especially south of US 30. Damaging winds,
  hail, and localized flooding are the primary threats.
  Confidence is low at this time.

- Cooler with chances for showers later this week into the
  weekend. Highs Friday through Sunday will be in the 60s.

&&

.DISCUSSION...
Issued at 146 PM EDT Mon May 6 2024

Powerhouse upper wave over the cntrl Rockies will close off across
the wrn Dakotas before spinning out through the Great Lakes Thu-Fri.
Downstream warm sector will broaden north into the OH valley
tomorrow and support decaying plains leftovers Tue morning. Cloud
debris and potential clearing in wake of morning activity will
dictate possible late day svr risk but destabilization likely
hindered here and which subdues overall svr risk.

Ewd pinwheeling upper low and attendant cold front will progress
into wrn areas Wed evening and ewd overnight. Strong/sharp return
flow ahead of this along with proximity of sfc warm frontal zone
general south of US24 may pose a resultant higher risk but potential
outflow spoiler remnant from dy1 further south may squelch that risk.
Nevertheless high chance to low likely pops retained in more
favorable periods.

Thereafter cool and showery as wrn flank of elongating upper low
holds back through the srn lakes, reinforced by secondary
disturbances digging down across the lakes Sat and again late
Sun.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 151 PM EDT Mon May 6 2024

A weak area of vorticity moves from the lower Mississippi Valley
into the Mid Atlantic Coast during this TAF period at the same time
that a surface high pressure system moves northeast into eastern
Canada. This sets the area up for winds out of the east ahead of a
warm front that attempts to move through Tuesday morning. A low
level inversion has formed below 850 mb and this allowed for times
of MVFR CIGs this morning as the inversion traps residual moisture
from recent rainfall and moisture from Lake Erie underneath it.
The diurnal trends this morning also helped CIGs rise above MVFR
so will keep that out of the afternoon TAFs. It`ll take until
moisture rises northward with the stronger moisture stream
Tuesday morning just behind the warm front. This also brings
additional opportunities for MVFR CIGs, and perhaps IFR, Tuesday
morning and there could be some showers or perhaps some
thunderstorms with the morning batch, but the instability
appears to be weaker. The NAM and even the ECMWF do show
increasing instability during the midday and afternoon hours
allowing for an opportunity for thunderstorms that could be
strong during the afternoon time, but that`s beyond this TAF
period.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...T
AVIATION...Roller