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Area forecast discussion 
National Weather Service northern Indiana
415 am EDT sun may 3 2015

Synopsis...
issued at 409 am EDT sun may 3 2015

High pressure across the middle Atlantic region will allow a
continued warming trend for the region today. Meanwhile...an
upper disturbance tracking along the Canadian border will drag a
cool front southward across the Great Lakes region Monday and
Monday night. This front combined with increasing moisture will
likely produce showers and thunderstorms Monday through Monday
night. Afternoon high temperatures will range from the upper 70s
to around 80 degrees. Lows tonight will fall back only to the
middle to upper 50s.

&&

Short term...(today and tonight)
issued at 408 am EDT sun may 3 2015

Minor moisture starved shortwave into wcntl in moving east-southeastward into
southwestern Ohio this afternoon. Modest increases in middle/upper level cloud cover associated
with feature in am hours. Incrsd insolation in afternoon hours along
with shortwave ridging in wake to again support a continued warming
trend fo surface-800 mb layer. Warmer start this am and 925mb afternoon temperatures on
order of about 3c warmer supports modicum of increases in already
warm/well above normal prior forecast. Strengthening background south-southwesterly
flow to minimize inland marine influence across County Warning Area...shunted northward
of Saugatuck/eastern Lakeshore inflection. Slight bump to min temperatures
as well tonight with County Warning Area planted within prefrontal thermal plume
along with sustained mixed blyr through the night. Gave token
slight chance of southern periphery of decaying WI mesoscale convective system to drape southeastward into
far northwestern County Warning Area toward daybreak Sans thunderstorms and rain mention. Certainly not as
strong as mav MOS given dominant wrly component to deep layer
motion vectoring and have undercut seemingly aggressive blended
approach.

&&

Long term...(monday through saturday)
issued at 408 am EDT sun may 3 2015

Models seem to have leveled off somewhat in handling of frontal
boundary across the region into Tuesday as main upper level
energy remains across northern Great Lakes. Most scenarios show
convection trying to move into far northwest parts of the area...but
weakening as they do. The residual mesoscale boundaries as well
as the front itself will help set the stage for convective
development Monday afternoon into Tuesday. While models vary to
some extent...all depict sufficient instability (some as high as
greater than 1000 j/kg) and little overall capping which would
suggest more than isolated coverage of storms. Part of this will
hinge on final resting place of the front and how much sunshine
can peak through the clouds. Storm Prediction Center day 2 outlook keeps area in
marginal risk and see no reason to disagree. Will maintain likely
probability of precipitation into Monday night but did increase further into upper end
likely mainly across the north. With the flow not overly strong
and precipitable waters 1.25 inches or higher...some areas could easily see
upwards of a half inch or more of rainfall. With the increased
cloud cover and shower/thunderstorm chances...temperatures will be cooler
with highs in the generally in the 60s and 70s.

Deep upper low will dig into the SW states and allow increasing
heights and subsequent nudge northward in the frontal
boundary...allowing the area to head back to above normal
temperatures into the 70s and 80s weds-Fri. Weak disturbances
will move through the flow towards the NE and allow for small
chances for showers and storms Friday into Saturday. Honestly can't
rule out a chance of a renegade shower/storm even for Wednesday/Thursday
during peak heating given some models showing a decent amount of
instability but no focused triggers.

&&

Aviation...(for the 06z tafs through 06z Sunday night)
issued at 156 am EDT sun may 3 2015

VFR met conds through the period. Upstream decay of convection across
Minnesota/IA/NE to provide some debris altocu/cirrus clouds...though of
little consequence. Change groups primary function to delineate
diurnal increase of S-southwesterly surface flow...with an incrsd/mixed
gradient flow maintaining in latter timeframe of forecast.

&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...none.
&&

$$

Synopsis...marsili
short term...Murphy
long term...Fisher
aviation...Murphy



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