Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 200822

Area Forecast Discussion
National Weather Service Northern Indiana
422 AM EDT Tue Mar 20 2018

Issued at 420 AM EDT Tue Mar 20 2018

Windy but mostly dry conditions will continue today. The
exception is areas south of US 24, where there are chances for a
rain and snow mixture, especially by late evening. Snow is likely
in this area overnight, with up to 2 to 4 inches of accumulation
possible by Wednesday morning. Dry weather is expected Wednesday,
with decreasing clouds. Highs today will be around 40. Lows
tonight will be around 25.


.SHORT TERM...(Today and Tonight)
Issued at 401 AM EDT Tue Mar 20 2018

The upper low was near Evansville and was drifting northeast over
southern Indiana. A very chilly northeast flow will continue as
this system moves closer to the forecast area. Another system
upstream will interact with this Indiana system downstream and
cause a fujiwhara effect where the upper low will curve more
north. This interaction will bring precipitation farther north,
reaching Portland and Lima. Thermal fields favor precipitation
becoming all snow tonight. Given favorable isentropic lift on the
northern fringe of this system, have raised snow amounts to 2 to 4


.LONG TERM...(Wednesday through Monday)
Issued at 401 AM EDT Tue Mar 20 2018

The upper trof over eastern North America will be slow to move
east as waves of energy of pacific origin reach the Midwest late
this week. The resulting unsettled pattern will bring a good
chance for rain or snow from Friday night through Saturday night
as thermal profiles remain close the rain/snow threshold.
Otherwise, temperatures each day through Sunday will be 5 to 10
degrees below normal with highs mainly from 40 to 45.


.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 135 AM EDT Tue Mar 20 2018

VFR conditions are expected at both the KSBN/KFWA terminals through
the TAF period. The main focus will be gusty northeasterly winds,
which will be more pronounced at KFWA at least overnight. Gusts up
to 22-28 knots have already been observed. Expect this to continue
through the overnight hours, and diminish by later Tuesday afternoon
as the pressure gradient slackens a bit. Low pressure to our south
will shift eastward, and there is disagreement among models with
regards to how far northward the precipitation shield (a rain/snow
mix) will lift. For now, left out of KFWA given the latest hi-res
runs keep things further southeast of the terminal.


LM...Small Craft Advisory until 11 PM EDT Wednesday for LMZ043-046.



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

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