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Area forecast discussion 
National Weather Service northern Indiana
152 am EDT Monday Mar 30 2015

Synopsis...
issued at 148 am EDT Monday Mar 30 2015

A warmer...yet still below normal day...is in store today with
dry weather along with a greater amount of sun and weaker winds
than seen on Sunday. Afternoon highs will push into the upper 40s
across south central Michigan to the middle to upper 50s into
west central Indiana. A rapidly approaching clipper system will
dip into the southern Great Lakes later tonight and provide a
chance of precipitation...though amounts should be light. Lows
will range from the upper 30s in south central Michigan to the
lower 40s in west central Indiana.

&&

Update...
issued at 850 PM EDT sun Mar 29 2015

Evening update mainly for cosmetic reasons to remove afternoon
wording...and to update probability of precipitation for latest trends. Strongest low
level moisture/thetae advection is shifting east of local area
early this evening. Lagging middle/upper level trough will provide
strongest forcing well north of area...with strong 500-300 NAM
q-vec divergence signal overspreading southern Great Lakes over
the next few hours. Some isolated/scattered light precipitation is
possible through 04z with passage of upper trough...and would
likely be in the form of liquid with surface wet bulbs recovering
along and immediately behind surface front. Updated forecast sent
mainly to fine tune pop trends this evening...but otherwise no
major changes to forecast elements.

&&

Short term...(this evening through monday)
issued at 310 PM EDT sun Mar 29 2015

Dewpoints in the middle teens across the area has afforded
significant evaporative cooling in the sub cloud layer this
afternoon. This has allowed for some sleet to mix in with the
rain...thus added sleet mention through 5pm. Expect low level
saturation to prevent any further refreezing after this time.
Cold front will pass through the area between 9pm and midnight
with a mostly dry passage expected. Kept slight chance/chance
probability of precipitation in through 02/03z given the potential for some showers to
develop along the front...but expect most of the frontal precipitation
to remain north of the area where the better upper level support
exists with the compact upper level wave.

Skies will gradually clear through the overnight period and set
the stage for a mostly sunny Monday. Bumped high temperatures up
a degree or two...but was reluctant to go much warmer given the
late onset of warm air advection across our area...and middle level
clouds moving in by the afternoon.

&&

Long term...(monday night through sunday)
issued at 310 PM EDT sun Mar 29 2015

Sure but steady follow aloft transition expect this period as height rises
across the eastern US build after Monday and in concert west/rockies mean
trough dvpmnt.

However details associated/west perturbed northern stream follow along the US/Canada
border remain fickle as series of SW troughs generally amplify
eastward every few days. Weak moisture starved system follows lt Monday night
and generally discounted but will keep west/low chance mention NE half.
More impressive SW follows again Thursday west/slwr eastward frontal progression
seen in most guidance Sans typically too progressive GFS
solution. Best model concensus implied chance for measurable rain is
Thursday afternoon. Otrws trailing wavy frontal boundary extending from parent SW
driving through southeast Canada looks to Foster some potential for
overrunning through Friday pending how and where remaining rockies
energy aloft ejects eastward. Intermodel trends suggest boundary hangs
further south which shunts moisture focus south along the Ohio River and
suggests little need for probability of precipitation here especially north half. Will go along
west/reduced all blend solution at this time.

Temperatures by and large moderating toward normal Tuesday on west/60s possible Thursday.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 149 am EDT Monday Mar 30 2015

VFR met conds through the period anticipated. Detail provided for
slow slackening of gusts with centroid of hiest 3 hrly pressure rises
still centered in northwestern in at 05 UTC. Ramping southwesterly 2kft flow late
tonight associated with strengthening warm air advection associated with clipper system
appears sufficient to provide late in forecast period breakout for low level wind shear
mention.

&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...Small Craft Advisory until 5 am EDT early this morning for
lmz043-046.

&&

$$

Update...marsili
synopsis...Murphy
short term...Bentley
long term...T
aviation...Murphy



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