Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 180921

Area Forecast Discussion
National Weather Service Northern Indiana
421 AM EST Sun Feb 18 2018

Issued at 320 AM EST Sun Feb 18 2018

A very wet week is ahead with warm temperatures just down the
road. Highs will climb to near 60 Monday, and then even warmer
Tuesday with highs near 70. A rainy period from Monday into
Wednesday will cause rises on rivers with flooding on many. In
addition to river flooding, areal flood is also likely particularly
over low lying and other flood prone areas.


.SHORT TERM...(Today and Tonight)
Issued at 312 AM EST Sun Feb 18 2018

Moisture will begin to surge northeast tonight as large scale
lift increases. Rain will develop by late tonight and spread
northeast late. Temperatures will begin to rise overnight in
response to very strong warm air advection.


.LONG TERM...(Monday through Saturday)
Issued at 312 AM EST Sun Feb 18 2018

Rounds of rain are ahead this week which will cause hydrologic
issues. Rainfall amounts of 3 to 5 inches are likely by the end of
the week as moisture continues to surge northeast. Several factors
continue to be very supportive for moderate to occasionally heavy
rain for an extended period. Precipitable water values will rise
above 1.3 inches at times which would top the climatological
values for this time of year. NAEFS/ensemble mean precip water
forecast values exceed the 99.5% percentile/climate for close to
48 hours from Monday afternoon into Wednesday, indicative of the
potential for an extreme event. An analog from Feb 29 to March 5
of 1976 produced 5.45 inches of rain at South Bend. WPC is
supportive of of heavy rainfall with widespread amounts this
upcoming week of 2.5 to 5 inches. After coordination with
surrounding offices, have updated the Hydrologic Outlook that was
initially issued yesterday morning to highlight flooding concerns
from these rainfall amounts. Highs Tuesday may set records and
have the potential to top the highest temperature so early in the


.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1232 AM EST Sun Feb 18 2018

Difficult forecast this period as hires models have significantly
slowed the progress of eastward clearing overnight and HRRR
trending toward LIFR cigs and vis toward 12z with some indications
of dense fog closer to KSBN. High pressure will slide in
overnight and winds will become less than 5 knots west of KFWA.
Not ready to jump on the dense fog with stratus appearing to be
left behind and limiting radiational cooling. Will have to monitor
trends overnight but latest satellite loop does show an overall
slowing trend to back edge of clouds. Trended terminals slower
with clearing until at least mid day when winds become southerly
and begin to increase.




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

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