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FXUS63 KIWX 220009

Area Forecast Discussion
National Weather Service Northern Indiana
809 PM EDT Wed Mar 21 2018

Issued at 250 PM EDT Wed Mar 21 2018

Cool and dry northerly flow is expected through the rest of the
week. Lows will generally be in the 20s with highs in the 40s. A
storm system will likely bring several inches of wet snow to areas
mainly south of US 30 in Indiana later Friday night into Saturday.
Drier air then returns Sunday into Monday, with temperatures
warming from the mid 30s to low 40s Saturday to near 50 degrees by


.SHORT TERM...(This Evening through Friday)
Issued at 250 PM EDT Wed Mar 21 2018

Dry/cool/subsident northwest flow is expected tonight through Friday 
on the backside of a persistent Northeast US/southeast Canada 
negative height anomaly. Temperatures will remain below normal for 
this time of year...lows generally in the 20s and highs in the


.LONG TERM...(Friday Night through Wednesday)
Issued at 250 PM EDT Wed Mar 21 2018

Negative NAO block over the North Atlantic looks to finally break 
down some this weekend into next week. This will allow for a 
trend toward milder (normal) temperatures next week as southwest 
flow ramps up behind a surface high dropping toward the Eastern 
Seaboard. This sfc high will unfortunately continue to feed in 
cool easterly winds in the low levels this weekend with 
temperatures remaining on the cool side. The only real threat for 
precipitation will be later Friday night through Saturday evening 
as a pacific shortwave undercuts the building ridge east-southeast
through the Mid MS/OH/TN Valleys. A band of precipitation within 
the elevated portion of the leading front/warm advection looks to 
clip areas along/southwest of US 30 in Indiana. Thermal profiles 
continue to suggest snow as the primary ptype on the northern 
fridge of this system with several inches of wet snow accumulation
possible here. Still some uncertainty regarding track/intensity 
so stay tuned for updates going forward. Dry otherwise into 
Sunday/Monday before rain chances return Tue-Wed.


.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 757 PM EDT Wed Mar 21 2018

VFR conditions are expected to continue through this forecast
valid period. Lingering weak upper level deformation forcing on
western periphery of mid Atlantic upper level low will continue to
break down this evening with gradual erosion/eastward progression
of mid cloud deck across far northeast Indiana/northwest Ohio.
Northwest winds of 10 to 15 knots will diminish to around 5 knots
this evening as gradient slackens, and as elongated ridge of high
pressure builds in through Thursday. Ridge axis should remain west
of terminals through this period, keeping northwest winds in place
through Thursday afternoon. Fairly deep mixing to 5000 feet should
allow for afternoon northwest winds back into the 10 to 15 knot
range on Thursday despite the slackening gradient.


LM...Small Craft Advisory until 8 AM EDT Thursday for LMZ043-046.



SHORT TERM...Steinwedel
LONG TERM...Steinwedel

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