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Area forecast discussion 
National Weather Service Indianapolis in
1243 PM EDT Friday Apr 18 2014

Update...

The aviation section has been updated below.

&&

Synopsis...
issued at 328 am EDT Friday Apr 18 2014

A weakening frontal boundary will pass through central Indiana this
morning with just a brief increase in clouds. High pressure will
then reestablish with dry pleasant weather over the weekend. Another
weak front will move through the Ohio Valley on Monday and Monday
night with showers and thunderstorms. Temperatures will remain mild
for much of the upcoming week.

&&

Near term /rest of today/...
issued at 953 am EDT Friday Apr 18 2014

Update...current forecast is on track. No updates are needed at this
time. Previous near term discussion follows...

Middle clouds associated with a steadily weakening frontal boundary
continue to spread into the forecast area early this morning. Thin
broken axis of very light showers exists with the boundary over
northern and central Illinois. Temperatures were mainly in the 40s at 07z.

Front has looked less and less impressive and now is likely to
completely wash out today as it runs into drier air and the high
pressure ridge east of the region. Area of light showers northwest
of the forecast area will track into lower Michigan this morning
with the remnant surface low...otherwise expect the middle clouds will
be the main highlight of the boundary for much of the forecast area.
Cannot completely rule out a sprinkle in the northern Wabash valley
over the next 4-6 hours but potential is so remote that it really is
not Worth any mention in the forecast. Have removed all mention of
probability of precipitation for today as a result.

Axis of middle level clouds should be through much of the forecast
area by early afternoon...with high pressure reestablishing as it
drops into the Great Lakes this evening. Model soundings keep
convective temperatures in the 60s this afternoon which will likely
translate to scattered cumulus development for the afternoon. Skies will
clear into the evening as the high builds south.

Consall guidance lined up with low level thermals well...with highs
rising into the upper 60s and lower 70s over much of central
Indiana.

&&

Short term /tonight through Sunday night/...
issued at 328 am EDT Friday Apr 18 2014

Forecast challenges are few through the short term...with a mild dry
Easter weekend setting up under high pressure.

High pressure centered over the Great Lakes tonight will maintain
firm control over Ohio Valley weather as it tracks into New England
and the middle Atlantic by Sunday night. A predominant east/NE flow
through early Sunday will advect dry air into the region...with
abundant sunshine and seasonable temperatures Saturday and cool clear
nights tonight and Saturday night. Mostly sunny skies will continue
into Sunday...with a few more clouds during the afternoon as surface
flow veers to southerly on the back side of the high. Clouds will
increase further Sunday night as a surface low with an associated
frontal boundary moves into Iowa and Missouri.

Temperatures...boundary layer temperatures will dip briefly on Saturday as the
center of the surface high passes to our northeast. Despite the
cooler 850mb temperatures...plenty of sunshine and dry easterly flow will
compensate with temperatures warming into the 60s. Warm advection arrives
Sunday with the southerly winds...setting the stage for temperatures to
rise into the 70s. Leaned towards warmer metmos for highs. Undercut
MOS guidance for lows tonight/Saturday night as near ideal
radiational cooling setting up with clear skies and light winds.
Typical cool spots throughout the forecast area may manage to sneak
into the upper 30s both nights. Easterly wind component off the city
center will keep lows at kind higher.

&&

Long term /Monday through Friday/...
issued at 250 am EDT Wednesday Apr 16 2014

Next week looks to be a typical Spring week for central
Indiana...with two systems impacting the area early in the week and
then toward the end of the week as well. In between...near to
slightly above normal temperatures and ample sunshine can be
expected as ridging at the surface and aloft make their way across
the region. Allblend handled the details very well and aside from a
few tweaks...no significant changes were required.

&&

Aviation /discussion for the 181800z taf issuance/...
issued at 1243 PM EDT Friday Apr 18 2014

VFR through the period.

Cumulus clouds that develop this afternoon will dissipate by early
evening with high pressure moving in. Winds should remain up enough
tonight to prevent fog formation.

A dry atmosphere will continue through Saturday with a few clouds.



&&

Ind watches/warnings/advisories...none.

&&

$$

Synopsis...Ryan
near term...Ryan/jh
short term...Ryan
long term...nield
aviation...50

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