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 49 50
FXUS63 KIWX 180730

Area Forecast Discussion
National Weather Service Northern Indiana
330 AM EDT Mon Sep 18 2017

Issued at 329 AM EDT Mon Sep 18 2017

A weak cold front moving across the area early this morning
is expected to cause scattered showers, mainly southeast of a
Monticello to Wauseon line. An upper level disturbance will
approach the Great Lakes and Ohio Valley Monday night into Tuesday
providing another chance of showers and isolated thunderstorms.
High temperatures for today and Tuesday will range from the mid
and upper 70s across the north, to the lower 80s south.


.SHORT TERM...(Today and Tonight)
Issued at 329 AM EDT Mon Sep 18 2017

Progress of the weak cold front has slowed over the past several
hours as it outruns what limited flow existed to the west of the
area. Pockets of widely scattered, mainly light showers were
persisting across the southeastern half of the area. Hi res models
all point towards this trend continuing through the morning
generally southeast of a Monticello to Wauseon line. Coverage of
showers may increase this afternoon in all areas, especially SE of
this line as steepening lapse rates and increasing instability
occur. However, models have backed off on more extensive coverage
until after 00Z tues and especially after 6Z associated with
another piece of energy moving into the region. As a result have
made changes to pops to better reflect trends today and slower SW
to NE arrival of shower chances later tonight.

Temperatures will be cooler than yesterday given expected cloud
cover and slightly cooler 850 mb temps behind the front. If more
clearing takes place than currently forecasted, highs could nudge
a few degrees higher.


.LONG TERM...(Tuesday through Sunday)
Issued at 329 AM EDT Mon Sep 18 2017

Showers and a few thunderstorms may be ongoing for the start of
the period until the departure of the upper level energy. Slight
chance to chance pops warranted into Tuesday evening before
frontal boundary moves back north of the area.

Models continue to advertise strengthening upper level trough to
the west and strong ridging to the east which should keep the
region high and dry with temperatures 5 to 10 degrees above
normal. While some instability will exist each afternoon/evening
lack of clear forcing mechanisms and influence of high pressure
over the eastern US should curtail any meaningful precip chances
through the remainder of the period. As has been the case the past
several days, have removed spurious pops Tues night through
Thursday night.


.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 132 AM EDT Mon Sep 18 2017

Mvfr conditions have developed behind the wk cdfnt movg across
the area early this morning, and are currently impacting SBN and
expected to move into FWA by daybreak. These low conditions should
be fairly short lived with vfr conditions across the area by
aftn. Stratus should redevelop tonight as front begins to move
back north in response to a low pressure system lifting ne into
the mid MS Valley.




LONG TERM...Fisher

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.