Area Forecast Discussion
Issued by NWS Northern Indiana

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
FXUS63 KIWX 131055

Area Forecast Discussion
National Weather Service Northern Indiana
655 AM EDT Fri Apr 13 2018

Issued at 242 AM EDT Fri Apr 13 2018

Partly clouds skies with a few showers mainly this afternoon over
northwest Indiana and southwest Michigan. Much  chances for showers
and a few thunderstorms will arrive for tonight night and continue
through much of Sunday as a large spring storm system across the
central United States slowly moves across the region. Rainfall
amounts of between 1 and 2 inches are expected during this period,
with locally higher amounts possible. Much colder air will filter
back into the region behind this system late Sunday into Monday with
a period of snow showers expected. Mild conditions are expected on
this afternoon with highs in the 70s.


.SHORT TERM...(Today through Saturday)
Issued at 242 AM EDT Fri Apr 13 2018

Warm frontal zone invof the highway 6 corridor will continue to buck
slowly nwd before stalling this aftn through srn MI or slightly
further south per absence of a greater advective push. This spells
potential temp bust far north and in light of current lake aggregate
adjustment ongoing this hour will shade toward highres 2m temps.
Otherwise held with general low/slight chc pops through nw zones
this aftn while steadily ramping through late evening as wedge of
higher theta-e positioned through the srn plains will take some time
in getting here. Trending HRRR solution scope though maybe on to
something with isold convection on nose of this feature mid aftn.

More concerted precipitation expected late tonight through Sat
morning in concert with strong moisture flux beneath ewd intruding
large scale jet divergence. In addition many individual solutions
indicate some degree of a frontal wave shedding ewd through the warm
frontal zone which should enhance rainfall through nrn/nern portions
of the cwa in this time period. This is also likely to allow sfc
frontal zone to buck back south Sat and have adjusted temps down
in tune with nrn neighbors.


.LONG TERM...(Saturday Night through Thursday)
Issued at 242 AM EDT Fri Apr 13 2018

Secondary zone of enhanced rainfall expected late Sat night through
Sun morning across ern half as large scale frontal wave develops
through the mid MS valley and lifts north ewd of deep occlusion
shifting through IL. Thereafter dry slot follows later Sun before
mid level comma head wraps back into the area late Sun night-Mon.
Given the degree of low level cold advection wrapping in underneath
suspect most of this will be snow and further cuts to max temps
probable. Nevertheless any accumulation potential will be confined
to grassy/elevated sfcs at best.

Low amplitude ridging follows with some moderation in temps through
Wed ahead of low amplitude/progressive sw disturbance ejecting out
of the cntrl Rockies and will put a kibosh on temps again Thu/Fri.


.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
Issued at 655 AM EDT Fri Apr 13 2018

VFR conditions will persist through the day as warm front inches
north and low levels remain dry. Showers and thunderstorms likely
at KSBN this evening as rich theta-e ridge advects into the area
ahead of approaching closed low but exact timing remains a bit
uncertain. Fuel alternate ceilings likely based on latest
guidance and IFR possible late in the period. Much later arrival
for KFWA and ceilings likely to remain VFR until after 06Z when
better moisture/rain pushes far enough east.


LM...Small Craft Advisory from 8 AM Saturday to 5 AM EDT Sunday for




Visit us at

Follow us on Facebook...Twitter...and YouTube at: is the U.S. government's official web portal to all federal, state and local government web resources and services.