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fxus63 kind 172231 
afdind

Area forecast discussion
National Weather Service Indianapolis in
631 PM EDT Tue Sep 17 2019

Update...
the aviation section has been updated below.

&&

Synopsis...
issued at 226 PM EDT Tue Sep 17 2019

High pressure across the Great Lakes and Ohio Valley will keep
central Indiana warm and dry until this weekend. Rain chances will
increase over the weekend as a cold front approaches.

&&

Near term /tonight/...

Issued at 226 PM EDT Tue Sep 17 2019

Stratus has been slow to mix across the north today under a
persistent inversion. Latest satellite images shows some erosion
with more celluar look to cloud field. Expect this trend to
continue into the evening with skies gradually becoming more
partly cloudy and eventually mostly clear across the north. Rest
of area seeing typical diurnal cu field which should also
dissipate toward sunset leaving behind some scattered to thin
broken cirrus overnight. Low temps will dip back into upper 50s
across the northeast and low 60s elsewhere.

&&

Short term /Wednesday through Friday/...

Issued at 226 PM EDT Tue Sep 17 2019

Quiet, dry and warm weather expected through Friday with large
scale upper ridge over the region. Temps should be well above
normal and well into the 80s each day. Models do show a little
increase in moisture drifting across far southern areas on
Thursday. This may lead to a few more clouds there in afternoon.

&&

Long term /Friday night through Tuesday/...

Issued at 155 PM EDT Tue Sep 17 2019

This period will be defined by the end of a persistent pattern and
the start of a new pattern.

The European model (ecmwf) shows the persistent ridge and high pressure still in
place across the eastern United States on Friday night into
Saturday...dominating Indiana's weather. This will continue to
bring dry and warm weather.

By Saturday night the European model (ecmwf) finally shows the upper ridge
departing to the east as a short wave arrives within the SW flow
aloft. Meanwhile Indiana will still be within thee warm sector at
that point...ahead of a cold front over the upper Midwest.
Several more upper short waves are then suggested to push across
Indiana through Monday...when the flow aloft becomes rather
troughy. Thus with these ingredients in play...have trended toward
in including pops on Saturday night through Monday. By Tuesday
the associated cold front with this system appears to have pushed
east of Indiana...with northwest flow in place aloft along with
subsidence. Thus for now...have trended toward a dry forecast
then. Expect temperatures through this period to remain at or
above seasonal normals.

&&

Aviation /discussion for 180000z taf issuance/...
issued at 631 PM EDT Tue Sep 17 2019

VFR conditions are expected throughout the forecast period.

The upper ridge anchored over the Ohio Valley will maintain dry
weather and ideal flying conditions for aviators across the
region through Wednesday. A large high pressure ridge at the
surface will keep winds from the east/southeast through Wednesday evening
with generally light flow. Could see some cu develop Wednesday
afternoon...otherwise just expect periodic thin cirrus across
central Indiana.

&&

Ind watches/warnings/advisories...none.

&&

$$

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