Scientific Forecaster Discussion
fxus63 kind 160938
Area forecast discussion
National Weather Service Indianapolis in
538 am EDT sun Jun 16 2019
the aviation section has been updated below.
issued at 208 am EDT sun Jun 16 2019
Wet weather is expected through at least Tuesday. A frontal
boundary is expect to linger across southern Indiana during the
beginning of the week. Several areas of low pressure will push
across Indiana during that time...producing rain. Rain could be
heavy at times.
Rain chances are expected to continue from Tuesday into next
weekend as the humid...wet...rainy weather pattern continues.
Near term /today/...
Issued at 208 am EDT sun Jun 16 2019
Surface analysis early this morning showed low pressure over Iowa
with a warm front extending southeast to central Indiana. Radar
continues to show convection development along the front across
central Indiana...mainly along I-74. More storms over central
Illinois were poised to push back into central Indiana with the
next couple of hours.
The models once again keep the lower level boundary in place
through the day. The wave over central Illinois is suggested to
push across central Indiana during the morning hours...exiting the
state by near 12z. Models then suggest a lull in upper support as
a break in between short wave is suggested. Time heights show
best lift ending by 12z...with still plenty of mid and lower level
moisture present...but subsidence arriving. Forecast soundings
show attainable convective temperatures this afternoon with
plenty of cape near 3000 j/kg and pwats over 1.6 inches. Thus best
forcing will not be in the area this afternoon...but given the
airmass and daytime heating...afternoon convection cannot be ruled
out. Thus will keep chances for storms all day...with best
chances this morning with the departing wave...and ramping chances
down in its departure...then back up in the late afternoon and
evening. Will stick to a blend on temps. Flooding may continue to
be a threat...but confidence for precise locations is low at this
time. As for temps...will stick close to the blends.
Short term /tonight through Tuesday night/...
Issued at 208 am EDT sun Jun 16 2019
Wet. Wet. Wet.
GFS and NAM suggest the pesky surface boundary will remain in
place across southern Indiana through at least Tuesday. Aloft...a
parade of short waves is expected to pass across the
boundary...each providing excellent forcing. A moist air mass
looks to remain in place through Tuesday night with dew points in
the 60s. Forecast soundings through Tuesday show a deeply
saturated airmass with pwats failing to fall below 1.3 inches and
ranging as high as 1.9 inches during the period. The GFS suggests
three short waves passing through Indiana...along the frontal
boundary. The first is suggested tonight...a second on Monday
night...and for now...the third and most organized in appearance
on Tuesday. We can expect some lulls in precip in between these
waves...but will still ramp up pops during each of these time
periods due favorable set up for heavy rains. Given the warm and
humid air mass in place will trend highs at or below the nbm and
lows at or above the nbm.
Again...flooding could be a threat early this week...and
depending upon how these systems play out...flood or flash flood
watches may be needed soon.
Long term /Wednesday through Saturday/...
issued at 152 am EDT sun Jun 16 2019
With active warnings in effect, will keep the long term discussion
Models and ensembles continue to hint at an active long term,
especially Wednesday afternoon and night, when the strongest wave
will move through the area with the front still hanging around.
Heavy rain and flooding will continue to be an issue.
Blend near normal highs look reasonable but confidence is not great
on specifics with a front nearby.
Aviation /discussion for the 161200z taf issuance/...
issued at 538 am EDT sun Jun 16 2019
Low confidence in exact timing of convection and potential poor
flying conditions, although in general expect widespread convection
to end 13z-15z only to return after 21z.
Winds will be southwest and west less than 10 knotsthrough 06z or so
Monday and then light and variable or calm.
Flash Flood Watch until 2 PM EDT this morning for inz021-028>031-