136
FXUS63 KIWX 162358
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
758 PM EDT Fri May 16 2025

.KEY MESSAGES...

- There is a chance for storms this evening, mainly between 7pm
  and 10pm EDT. A few thunderstorms could become severe with
  damaging winds the primary threat, mainly south of US 24.

- Cooler and breezy on Saturday.

- Periodic rain chances return next week, mainly Tuesday through
  Thursday.

&&

.UPDATE...
Issued at 745 PM EDT Fri May 16 2025

Fairly complicated set up here in the short term for here in
northern Indiana. Which is probably not so much for forecasters
for locations across the High Plains in which these very dry
low level convective events are more commonplace. We have the
synoptic winds from the southwest being amplified by convective
outflows. These winds have then been kicking up dust/dirt back
over central IL and has pushed this dust into northern IN with
even some additional dust being added locally. Did address the
wind/dust potential initially with an SPS but with the increase
in wind speeds/dust decided to go with a combination of Severe
Thunderstorm warnings for the winds and a blowing dust advisory
for of course the dust. This is one event that will stand out in
the future for sure.

&&

.DISCUSSION...
Issued at 215 PM EDT Fri May 16 2025

A shortwave, 70-80 kt 500 mb jet, and an attendant cold front track
through this evening into the early overnight through the base of an
Upper Midwest upper low. The associated shot of deeper ascent and
some low level moisture return with a developing low level jet
should bring a period of scattered showers/storms to most of the
area this evening. Still cannot rule out a few strong to severe
storms, mainly south of US 24, as shear profiles are favorable
for organized convection. Instability is the limiting factor
however with MLCIN and dry air to overcome, though incoming
height falls/cooling aloft, and some last minute low level
theta-e advection, should eventually allow updrafts to break the
cap with MLCAPE potentially surging into the 1000-1500 j/kg
range (highest southeast of US 24). High DCAPE with steep 0-3km
lapse rates favor a downburst wind threat if any multicell
clusters/lines emerge. Overall confidence in anything more
than isolated strong to severe cells is low, with greater probs
for severe storms off to the south near the primary
moisture/instability axis.

Cold advection on the southern fringes of a stacked low moving east
through the Great Lakes region will provide significantly cooler and
breezy conditions post-frontal later tonight into Saturday. Cyclonic
flow around the low will also allow stratocu to build in for a time,
especially north of US 30 where non zero chances for a rogue
sprinkle/shower will exist. Sunday is definitely the preferred
weekend day weather-wise as high pressure nudges in from the north
with sunshine, lighter winds and slightly warmer temps.

Next week continues to look wet at times as an upper low cuts off
and slowly tracks east through the Central US and Great Lakes. The
greatest chances for rain are the Tuesday through Thursday periods,
with temperatures generally below average for mid-late May.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 757 PM EDT Fri May 16 2025

Complicated TAF period at least in the short term with southerly
gusty winds being amplified by thunderstorm outflows and also
kicking up dust and locally dropping vsbys due to the blowing
dust. This will be expected through 03z Sat for KSBN and 04z
KFWA. Will continue to monitor as this may take a bit longer to
push through. Wind gusts up to 35 kts expected with slightly
higher gusts possible at times through 04z Sat. South to southwesterly
Winds back to more westerly late in the period and slightly
decrease through the remainder of the TAF period. Gusts still
expected around 25 kts.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Blowing Dust Advisory until 11 PM EDT /10 PM CDT/ this evening
     for INZ005>009-012>015-017-018-020-022>027-032>034-103-
     104-116-203-204-216.
OH...Blowing Dust Advisory until 11 PM EDT this evening for OHZ001-
     002-004-005-015-016-024-025.
MI...Blowing Dust Advisory until 11 PM EDT this evening for
     MIZ078>081-177-277.
MARINE...Small Craft Advisory until 5 PM EDT Saturday for LMZ043-046.

&&

$$

DISCUSSION...Steinwedel
AVIATION...Andersen
UPDATE...Andersen