Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 202242

Area Forecast Discussion
National Weather Service Northern Indiana
642 PM EDT Thu Apr 20 2017

Issued at 329 PM EDT Thu Apr 20 2017

A cold front will usher in much colder air Friday, lingering into Saturday
with highs only in the 50s (cooler near the lakeshore). Warmer
temperatures and rain chances will return next week.


Issued at 619 PM EDT Thu Apr 20 2017

Severe threat slowly diminishing with watch being cleared behind
the cold front as it progresses east.

A few severe storms developed ahead of the front across Putnam
county, dropping hail to at least the size of half dollars.
Along the cold front itself, line of storms persists but has
remained below severe levels for at least the past hour or so.
Mixed layer CAPE on the downward trends as this area has been
worked over a fair amount. Marginal threat ahead of the front
warrants holding onto the watch for now, but if downward trend
continues watch may be dropped early.


.SHORT TERM...(This Evening through Friday)
Issued at 329 PM EDT Thu Apr 20 2017

Thunderstorms dotting the forecast area generally east of a
Logansport to Coldwater line with greatest concentration along the
pre-frontal trough now moving into NW Ohio. Storms have struggled
to organize with mainly pea size hail reported and pockets of
40 to 55 (48 kt gusts at Ft Wayne). As the first area departed,
sufficient recovery occurred to allow for a narrow area of sct
storms to develop from Ctrl Illinois into portions of N Indiana.
Actual cold front not too far behind this second line resulting in
a rapid end to all storm chances through the remainder of the
afternoon. Will likely clear watch as back edge of the storms
exits impacted areas.

Vis satellite showing extensive stratocu field to slowly work
east. Could be a period of clearing immediately behind the front
before it arrives. Have increased clouds cover to mostly cloudy
with slower trends on clearing into Friday. Highs Friday will be a
good 15 to 20 degrees cooler across the area with mid 40s NW to
upper 50s SE.


.LONG TERM...(Friday Night through Thursday)
Issued at 329 PM EDT Thu Apr 20 2017

Deep Hudson Bay closed low will remain in place into early next week
before slowly shearing apart and ejecting NE. Influence of the low
will keep moisture and warmer temperatures well suppressed as
longwave trough rounds the base of the trough. Period of somewhat
below normal temperatures will dominate with a shot at some frost
especially Sunday morning. Moderation in temps will occur as
Great Lakes trough exits stage right and heights increase ahead of
the next wave dropping out the Plains by Monday night.

The arrival of the Plains wave will bring a chance for showers to
the area, but not until closer to Wednesday as first embedded wave
shoots to the west of the region before main wave edges east. No
more than chc pops at this point with temperature soaring back above
normal into the 70s.


.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 639 PM EDT Thu Apr 20 2017

Cold front will be long gone from KFWA by the valid time of the
TAFS with winds becoming W and NW and large strato cu field
slowly spreading east with MVFR cigs. Potential for some
improvement on Friday as drier air may erode the cloud cover, but
given the degree of cold air will probably be hard to get rid of.


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



LONG TERM...Fisher

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