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Area forecast discussion 
National Weather Service northern Indiana
434 am EDT Wednesday Apr 1 2015

issued at 432 am EDT Wednesday Apr 1 2015

Weather will be quiet today with high pressure still in control.
Skies will be mostly sunny with temperatures warming into the 60s.
Clouds will increase tonight with a slight chance for rain late.
Lows will only drop into the 40s and 50s. Showers and
thunderstorms are expected on Thursday as a cold front slides
across the region.


Short term...(today and tonight)
issued at 429 am EDT Wednesday Apr 1 2015

Quiet weather continues for most of this short term period. High
pressure centered over south central Ohio early this morning will
continue to drift east. Middle level ridge will move over our area
today providing mostly sunny skies and light winds to start the day.
Gradient will increase a bit western areas middle afternoon as ridge
axis moves east. Mixing heights will increase leading to highs in
the upper 60s west and lower 60s east. Pressure gradient continues
to tighten tonight ahead of next short wave and associated surface low
pressure. Moisture advection really increases after 06z and should
see an increase in clouds along with rising dewpoints. As with
previous shift concerns cannot rule out developing showers and
isolated thunderstorms and rain after 09z with increased moisture and low level jet
impinging on western areas. While best chances remain after 12z Thursday
have allowed a low pop to continue late tonight. Low temperatures will be
able to dip into lower 40s east while western areas to only fall in
lower 50s.


Long term...(thursday through tuesday)
issued at 429 am EDT Wednesday Apr 1 2015

An upper trough had moved onshore over the western North American
coast. This system will move east today and is expected to reach
the area Thursday. Concern for the potential for severe storms
Thursday. The latest 12km NAM supports destabilization along and
southeast of the front by early Thursday afternoon. Even with
limited looks like the best chance for storms is along and
southeast of a line from Winamac to Etna Green to Hillsdale. The
best chance for severe storms is south and southeast of feet Wayne.
The NAM is indicating a narrow band of dew points in the lower 60s
along with afternoon cape values rising to around 1000 j/kg. In
addition to this instability... strong low and middle level winds of 60
to 70 knots are expected over the area causing exceptional low level
shear and helicity values including 0-1 km helicity of 469 combined
with 25 M/S shear per NAM BUFKIT. The 0-3 km values are 700 m2s2
with 45 M/S shear. In coordination with the Storm Prediction
Center...will include mention of severe storms in the hazardous
weather outlook.

A second wave will follow the initial system and bring the chance
for more rain Thursday night and Friday. During Friday night...
the rain should change to snow before ending...but no snow
accumulation is expected.

For the rest of the period...the upper level flow should become
southwest...and allow temperatures to rise above normal by Tuesday.
Rain chances will increase again early next week with the arrival of
short wave troughs ejecting out of the main trough.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 122 am EDT Wednesday Apr 1 2015

VFR conditions with this package as middle level ridge cross the
region. Winds light and variable into middle morning becoming
southwest 5 to 10 knots. Should see gradient increase late
afternoon and evening with 10 to 15 knots from the south.


Iwx watches/warnings/advisories...


short term...Lashley
long term...skipper

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