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fxus63 kind 241141 
afdind

Area forecast discussion
National Weather Service Indianapolis in
741 am EDT Wed may 24 2017

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

&&

Synopsis...
issued at 330 am EDT Wed may 24 2017

Wet weather will occur today through midday Thursday as low pressure
deepens over the Ohio Valley and drifts north across Indiana. This
low pressure system will move on to the east and a ridge of high
pressure will move east across Indiana Thursday night and early
Friday. Wet weather will return late Friday through most of the
weekend as a frontal system and a couple of low pressure systems
move our way. Temperatures will become a little cooler early
next week as an upper trough digs into the upper Midwest.

&&

Near term /today through Thursday/...
issued at 330 am EDT Wed may 24 2017

Showers have been increasing over the lower Ohio Valley as well
as northeast Illinois and parts of extreme Northwest Indiana.
Surface chart indicates a weak area of low pressure centered a
little south of Louisville at 07z. Models strengthen this
low pressure system as a closed upper low over eastern Iowa
moves southeast. For today leaned heavily towards the high
res model which spread numerous showers into our southwest and
southern sections this morning and spreads this area north across
the rest of our region this afternoon. Will go with definite probability of precipitation
most areas today...but this will not happen until this afternoon
across our north.

The low pressure system will deepen and move north across central
Indiana today. Models indicate mu CAPES of 500 to 1000 j/kg this
afternoon which will result in a chance of thunderstorms this
afternoon and a slight chance of thunderstorms into early evening.

Will continue with likely probability of precipitation all but far west tonight and then
decreasing chance of showers Thursday as the surface low moves on
to the east.

With clouds and precip cut temperatures slightly across the southwest
half of our forecast area today. There may be a period late morning
where temperatures could rise into the upper 60s across our northeast
before the showers arrive. Anyways highs all areas will be in the
60s today. Went with lows in the middle 60s tonight which was
slightly above a MOS blend. On Thursday highs will range from the
middle 60s east to lower 70s southwest where some sun may occur by
late Thursday.

&&

Short term /Thursday night through Friday night/...
issued at 330 am EDT Wed may 24 2017

A ridge of high pressure will move east across Indiana Thursday
night and Friday bringing a period of dry weather. An area of
low pressure will move our way Friday night. The GFS spreads
precipitation by late Friday morning...while NAM keeps US dry
until Friday evening...while the Euro and Canadian by late Friday
afternoon. Will go with a blend...but slightly slower than consall
and superblend probability of precipitation. Raised probability of precipitation to likely some areas Friday evening
as this is most likely time for precipitation to occur and models
indicate pretty good forcing.

Concerning temperatures stayed close to a MOS blend with highs
75 to 80 Friday and slightly above a MOS blend Friday night with
lows in the lower to middle 60s.

&&

Long term /Saturday through Tuesday night/...

Issued at 341 am EDT Wed may 24 2017

Models continue to trend toward an active weather pattern
throughout the extended period. First, showers and thunderstorms
are expected to develop along a surface low's frontal boundary on
Saturday. After that, additional forcing will be provided by an
upper low progged to drop into the upper Midwest for the second
half of the weekend. There will be a lull in activity from Sunday
night into Monday as the forecast area falls into a dry slot.
However, additional waves of energy will resume around the upper
low by Monday afternoon, triggering additional showers and
thunderstorms through the end of the period. Meanwhile,
temperatures will start out above normal for the weekend with
highs in the upper 70s/low 80s, but they will trend closer to
normal by Monday and Tuesday.

&&

Aviation /discussion for the 24/1200z taf issuance/...

Issued at 724 am EDT Wed may 24 2017

Conditions will fluctuate between VFR and MVFR this morning with
some reduced visibilities and rain showers in the area. As forcing
increases later today with deepening low pressure system, rain
chances will increase, and conditions will trend more toward MVFR
category. In addition, isolated thunderstorms cannot be ruled out
this afternoon and evening. After that, conditions could
deteriorate even further to IFR conditions overnight. Meanwhile,
winds will generally be northwesterly at 5 to 10 kts.

&&

Ind watches/warnings/advisories...none.

&&

$$

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