Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 240527
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
127 AM EDT Mon Jul 24 2017

.SYNOPSIS...
Issued at 120 AM EDT MON Jul 24 2017

Drier and cooler air will continue to filter into the region
behind a cold front overnight. The upcoming week will not be as
hot or humid as last week and will feel very comfortable for late
July. The next chance for showers and thunderstorms arrives
Wednesday night into Thursday. High temperatures today will reach
the middle to upper 70s and highs on Tuesday will be in the upper
70s to lower 80s. Low temperatures Monday night will be between 55
and 60.

&&

.SHORT TERM...(This Evening through Monday)
Issued at 210 PM EDT Sun Jul 23 2017

The main focus for the remainder of the afternoon and early evening
will be on shower/storm coverage and intensity. Very
subtle/diffuse boundaries on the leading edge of an approaching
mid level shortwave trough may provide enough of a focus for
isolated to widely scattered showers/storms across ne IN/nw OH/sc
Lower MI during the mid-late afternoon. Weak forcing/convergence
with overall moisture quality in question should limit the
coverage and intensity, though cannot rule out an isolated
stronger storm given MLCAPE values near 1500-2000 j/kg and deep
layer shear ~30 knots.

The other feature of note will be scattered convection expected to
develop across ne IL/srn WI near the primary cold front. This
activity will attempt to survive into areas mainly west of US 31 early
this evening, weakening and shifting more south with time thanks to
waning diurnal instability and orientation of main instability
axis.

Passage of the synoptic scale trough will allow cooler and much
drier air to filter in later tonight into Monday as flow in the low
levels back north-northeast post-frontal. Subsidence/height rises in
wake of the trough, with sfc high pressure gradually building in
from the northwest, will result in dry conditions and only a
scattered CU field on Monday.

&&

.LONG TERM...(Monday Night through Sunday)
Issued at 210 PM EDT Sun Jul 23 2017

Dry and noticeably less humid conditions will persist into Monday
night and Tuesday under high pressure surface and aloft.
Heat/humidity levels then increase into Wednesday as southwest
flow returns in advance of an approaching cold front expected to
move through the local area later Wednesday night-Thursday with
the only real threat for showers/storms during the long term
period. Chances for severe storms appear low given marginal shear
profiles and unfavorable diurnal timing (another weakening/early
morning MCS?). Ample moisture return (not surprising for late July
in the Corn Belt) and slowing nature to the frontal
slope/convection as it becomes more aligned to weaker mid- level
flow could pose a heavy rain threat. This return to storm chances
and higher humidity will be brief as the next Canadian shortwave
southeast through the Great Lakes brings high pressure and dry
conditions back into the picture Friday into next weekend.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 119 AM EDT Mon Jul 24 2017

Just some mid level clouds at this time across the local area but
MVFR cigs upstream over Michigan expected to drop south overnight
and move into terminals. These clouds will hang around through mid
morning before mixing allows bases to rise to VFR. Clouds will
eventually move out later in the afternoon and evening. Winds will
veer to northwest then north and will be in the 5 to 10 knot range
overnight and 8 to 13 knot range on Monday.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement through this evening for INZ003.

MI...Beach Hazards Statement through this evening for MIZ077.

OH...NONE.
LM...Small Craft Advisory until 8 PM EDT this evening for LMZ043-046.

&&

$$

SYNOPSIS...Lashley
SHORT TERM...Steinwedel
LONG TERM...Steinwedel
AVIATION...Lashley


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