Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 211753
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
153 PM EDT Wed Sep 21 2016

.SYNOPSIS...
Issued at 318 AM EDT Wed Sep 21 2016

Above normal temperature will continue into at least Thursday with
highs well into the 80s both days. Shower and thunderstorm chances
may return by Sunday as a frontal boundary to the north sinks into
the area and a slow moving front moves towards the area from the
west. More seasonable temperatures can be expected next week.

&&

.UPDATE...
Issued at 1146 AM EDT Wed Sep 21 2016

Upstream convective complex fell apart as expected with just a few
showers entering the northwest. 14z HRRR is now trying to develop
some convection across NW Indiana with outflow from convection.
SPC Mesoanalysis does show a capped but slightly unstable
environment and any outflow could spark a storm or two if weak
capping erodes. Have updated to include slight chance pops from
the US 30 corridor northward over at least central and western CWA
for this afternoon. Once debris cloudiness thins temps should
rebound later this afternoon to near 80 north and lower to middle
80s south.

&&

.SHORT TERM...(Today and Tonight)
Issued at 318 AM EDT Wed Sep 21 2016

Another warm day will be in store for the region as frontal boundary
re-establishes itself across southern Lower Mi and eventually shifts
north. As advertised, convection quickly blossomed across SE
Minnesota and quickly went upscale. 40 to 45 kt LLJ was focused ahead
of the convection allowing for continued maintenance of a bowing
segment taking aim on La Crosse WI as well as a large area of
rain/embedded storms across central WI. Convection across central WI
should continue east and likely weaken as it outruns best low level
support. Storms over SE MN/WCtrl WI into NE IA will continue to drop
SE and remain elevated keeping overall severe threat minimal. For
our area specifically it would appear that any convective threat has
been nearly eliminated. Only lingering concerns is unstable
atmosphere across W/NW areas where CAPE values will push into the
1500 to 2000 J/KG range. If an outflow boundary emanates from the
convection and moves into this area this afternoon, could see some
isolated convection. However confidence very low in this scenario so
no addition of storms with punt to day shift to monitor trends.

Highs will reach into the lower to middle 80s with somewhat
higher humidity values.

&&

.LONG TERM...(Thursday through Tuesday)
Issued at 318 AM EDT Wed Sep 21 2016

Proximity of key features would tend to suggest that the forecast
area will remain high and dry into at least Sunday with highs well
into the 80s Thursday and possibly Friday. Frontal boundary will
remain draped north of the area with complexes of storms moving
along it through Friday before main focus shifts to the west with
stout trough and cutoff low that will meander towards the region
next week to bring increasing chances for precipitation and what
appears to be the potential for a shot of colder air with MEX
guidance showing highs only in the lower to middle 60s by Wednesday.
Grids to not reflect that drastic a difference as ECMWF remains
slower and not quite as deep on the trough. After several days of
above normal temps certainty exists on a return to near if not below
normal temps next week. How fast this occurs remains to be seen.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 135 PM EDT Wed Sep 21 2016

Focus for convection should remain primarily north and west of the
local area this period as effects of broad mid level ridge and
capping issues persist. Outflow/convective vorts from upstream
convection may be enough to support an isolated shower or storm
at KSBN late this afternoon, but confidence remains too low for
inclusion at this time. Otherwise, light south/southeast winds to
become light and variable tonight, and then south-southwest 5 to
10 knots Thursday. Some potential of some shallow fog once again
early Thursday morning, but not expecting significant impacts at
this time.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

UPDATE...Lashley
SYNOPSIS...Fisher
SHORT TERM...Fisher
LONG TERM...Fisher
AVIATION...Marsili


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