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fxus63 kiwx 182235 

Area forecast discussion
National Weather Service northern Indiana
635 PM EDT sun Aug 18 2019

issued at 627 PM EDT sun Aug 18 2019

Scattered thunderstorms will role east through the area into the
evening. An isolated strong to severe thunderstorm will be
possible, best chances along and southeast of US 24.
Periodic low chances for showers and thunderstorms and warm
temperatures will persist into Monday and Tuesday, followed by
cool and dry conditions Wednesday through Saturday.


Short term...(this evening through monday)
issued at 233 PM EDT sun Aug 18 2019

MLCAPE has increased to near 2000 j/kg and cin has largely eroded
along and in advance of a composite outflow boundary draped near
the US 24 corridor. Coverage is rather isolated as of 1815z but
expected to increase mid-late afternoon as a convectively aided
impulse approaches from the mid MS valley. Most of this activity
is expected along/southeast of US 24, though additional
development possible on the edge of stable bubble to the north as
boundary layer attempts to recover with outflows in the vicinity.
Effective shear values in the 25-30 kt range and moderate
instability may be enough to support a few strong to severe storms
with wind the primary threat.

Chances for showers/storms diminish later this evening into
Monday morning behind these series of shortwaves, though a few
leftover showers not out of the question as the main synoptic cold
front and pooled moisture drop in from the northwest. Fog and
stratus may be able to fill in otherwise later tonight given ample
low level moisture. This remnant moisture and diurnal heating may
contribute to iso-sct convection by Monday afternoon near the
weak front. Storms should stay below severe limits and mainly
confined to southern/eastern zones.


Long term...(monday night through sunday)
issued at 233 PM EDT sun Aug 18 2019

The next chance for a round of convection will come later Tuesday
into Tuesday night as the next convective complex and associated
Theta-E surge rides the northeast fringe of a persistent south-
central Continental U.S. Upper ridge. This convection will pose a severe
threat, though higher probabilities appear to be west of the iwx
County Warning Area at this time. Quiet weather and lower humidity then becomes
the story mid-late week as negative height anomaly dropping into
southeast Canada finally forces active frontal zone off to the


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 627 PM EDT sun Aug 18 2019

A shortwave will bring scattered convection through kfwa early
this evening. Brief MVFR/IFR restrictions can be expected with
this activity, with a low chance for a strong to severe storm
(hail & wind). Mainly dry and VFR otherwise into tonight. A
frontal boundary will then drop into northern in Monday morning
with MVFR cigs/vis possible.


Iwx watches/warnings/advisories...


short term...steinwedel
long term...steinwedel

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