Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 131501

Area Forecast Discussion
National Weather Service Northern Indiana
1101 AM EDT Wed Sep 13 2017

Issued at 1100 AM EDT Wed Sep 13 2017

The remnants of Irma will continue to slowly lift north across
the Ohio Valley through tonight. Impacts from this system will be
minimal for the local area, with light showers generating
rainfall amounts around or less than a tenth of an inch. Cooler
weather can be expected today given abundant cloud cover and light
rain. Highs should be in the upper 60s to lower 70s. Areas of fog
are possible tonight over northwest areas. The fog should lift
after daybreak. Temperatures will then gradually warm through
Sunday with highs in the 80s this weekend. The next chance of rain
after the remnants of Irma move out will be late in the upcoming


Issued at 1100 AM EDT Wed Sep 13 2017

A couple of areas of more organized rain showers noted on regional
radar imagery late this morning. The first area associated with
theta-e gradient which lifted northwest through the area last
night, has now shifted across far northwest Indiana and northeast
Illinois and should no longer impact the area. Secondary low level
theta-e surge across northeast Indiana has been responsible for
band of light rain showers, which will progress across north
central/far northeast Indiana through mid afternoon. A more
organized area of light rain is taking shape across central
Indiana and should expand north-northeast through the mid-late
afternoon as vort max/deformation zone shift northward across
northeast Indiana. Greatest coverage in late afternoon/early
evening expected roughly along and east of the I-69 corridor
following this deformation forcing. Previous forecast in good
shape, but may need some slight upward adjustment in PoPs for
areas along and east of I-69 later today. Rainfall amounts are
expected to remain on the light side.


.SHORT TERM...(Today and Tonight)
Issued at 535 AM EDT Wed Sep 13 2017

The initial outer band remnant of Irma was drifting north across the
forecast area. This system was able to still generate a few
hundredths of rainfall overnight. A second band should move into the
area later today before the upper low lifts northeast. Given the
trajectory of this system, the best chance for rain is this evening
from Portland to Lima. Kept temperatures cool today, especially
south of Ft Wayne where highs should only be in the 60s.


.LONG TERM...(Thursday through Tuesday)
Issued at 535 AM EDT Wed Sep 13 2017

Some light showers are possible early Thursday as the remnants of
Irma move northeast; otherwise, little if any rain is expected
through Sunday as upper level ridging expands over the area.
Temperatures will warm into the 80s this weekend and stay above
normal through early next week. There is a chance for showers
Sunday night and Monday with the next system.


.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 539 AM EDT Wed Sep 13 2017

Band of -shra along east-west oriented sfc trof and leading edge
of low level moisture lifting slowly north across central/nrn IN
attm. Widespread mvfr ceilings and patchy ifr conditions
along/south of the trof should cont to impact FWA this morning and
spread into SBN around 12z. Although sfc trof expected to lift
north of the area today and sfc low currently over srn IL
dissipating, mid-upr level low will persist through the period and
provide contd forcing for rain bands to move into nrn IN
today/tngt as deep moisture currently evident on water vapor
lifting north across srn IN reaches our area. Sfc Winds will be
light or calm overnight as pressure gradient becomes very weak.
Mid-upr low will be shifting east into OH providing some drying
aloft over nw IN late which may allow lifr visibilities in fog to
develop, while deeper moisture over ne IN should result in just a
lowering ifr stratus deck with mainly ifr/mvfr vsbys in BR.




SHORT TERM...Skipper
LONG TERM...Skipper

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