Scientific Forecaster Discussion
fxus63 kind 221011
Area forecast discussion
National Weather Service Indianapolis in
611 am EDT sun Sep 22 2019
the aviation section has been updated below.
issued at 415 am EDT sun Sep 22 2019
A cold front will move through central Indiana starting this
evening and through tonight. The front will bring a a chance of
rain across the area. Cooler temperatures are expected for the
beginning of the week before increasing to the 80s again by the
end of the week. There is another chance of rain Wednesday night.
Near term /today/...
Issued at 415 am EDT sun Sep 22 2019
Cold front will be approaching the area today. There may be some
light showers ahead of line this morning but those should stay
mainly to the northwest of the forecast area. Clouds will increase
throughout the day as will wind speeds. Models show the pressure
gradient tightening up ahead of the front which will lead to winds
out of the southwest at 10 to 20 kts and gusts up to 25 to 30 kts
throughout the day. The line of storms, moving in from the
northwest, could reach central Indiana by the early evening hours
but most of the impacts are expected to occur after the near term
period. Highs today will be in the mid to upper 80s.
Short term /tonight through Tuesday night/...
Issued at 415 am EDT sun Sep 22 2019
An upper low is tracking across the upper Great Lakes and moving
towards the New England states. An associated cold front will affect
the area starting before, and continuing through the beginning of
the short term. The rainfall amounts continue to look less than
it did in days past with less than half an inch for most of the
area and some slightly higher amounts for the more northwestern
counties. Due to the timing of the front shifting to the
overnight hours, the threat for severe weather has also decreased.
By Monday morning, the precipitation will have moved east out of
the area as another high pressure system moves in behind it.
Conditions will be more fall like for the beginning of the week
with highs in the 70s and lows in the 50s.
Long term /Wednesday through Saturday night|/...
Issued at 304 am EDT sun Sep 22 2019
Will the Summer ever end? Can these above normal temps continue
indefinitely? The answer to these questions and more in your
extended discussion below.
Yes, the Summer will end and it will get cooler...just not during
this period as Summer continues to hang on. The European model (ecmwf) continues
the trend on Wednesday into Thursday of a large trough passing
through the Great Lakes. However...little forcing energy appears
to reach Indiana. The associated cold front also appears to get
stretched out and barely pass into the Hoosier state. Thus with a
lack of forcing...confidence for rain is low...but will keep a
mention for now. Surely a soaker is not expected.
In the wake of this weak front...Summer returns. Strong ridging
once again builds across the eastern United States as strong warm
surface high pressure settles across the deep south. The high is
expected to continue to control Indiana weather late this work
week with dry weather and above normal temperatures.
Aviation /discussion for the 221200z tafs/...
Issued at 604 am EDT sun Sep 22 2019
Mainly VFR conditions are expected this taf period.
A warm and humid air mass will remain in place for the first part
of this taf period as high pressure departs to the east. Forecast
soundings and time heights show a dry column this morning and
afternoon with attainable convective temperatures in the lower
80s. Thus have included some VFR cigs this afternoon.
Overnight a cold front will push across the area. Showers with
isolated thunderstorms and rain will be possible along and ahead of the front.
Confidence for thunderstorms and rain at this point is low...thus have only included
shower mention as these features pass for now. With the showers
and isolated storms brief MVFR conditions will be possible.