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fxus63 kind 212106 

Area forecast discussion
National Weather Service Indianapolis in
406 PM EST sun Jan 21 2018


The synopsis, near term, and short term sections have been
updated below.


issued at 400 PM EST sun Jan 21 2018

Low pressure will strengthen over the plains this evening and push
northeast into the Great Lakes through early week, bringing
showers and at times drizzle, with a slight chance for a rumble of
thunder or two late tonight into Monday. Shower chances will
continue into Tuesday, with perhaps a few snowflakes late Monday
night into Tuesday morning. The rest of the work week will be dry
as high pressure pushes across the region. The next chance for
precipitation will come next week as a frontal system moves out of
the north Central Plains.


Near term /tonight/...
issued at 400 PM EST sun Jan 21 2018

Warm advection will continue tonight ahead of the strengthening
low pressure system over the south Central Plains. As such, expect
temperatures to remain mostly steady. A few showers may develop,
but mainly expect drizzle especially early. Precip chances will
increase lately especially northwest, and sref probabilities
indicate outside potential for a rumble of thunder there as well.
Will carry a slight chance.

Patchy fog will likely remain through the evening but visibilities
should improve a bit as winds pick up a bit later tonight.


Short term /Monday through Wednesday/...
issued at 400 PM EST sun Jan 21 2018

Categorical pops will be necessary from west to east tomorrow as
the front pushes through the area. Will also carry a slight chance
of thunder as well.

May see a bit of a dry slot lull early Monday night before the
upper low moves in and showers increase again. Most of the
precipitation will likely be liquid, although cannot rule out some
snowflakes late Monday night into Tuesday, especially north. No
significant accumulation is expected.

The remainder of the short term will be dry as high pressure
builds into the area.

Consensus temperatures appeared generally in the ballpark and
required few tweaks.


Long term /Wednesday night through Sunday/...
issued at 230 PM EST sun Jan 21 2018

European model (ecmwf) shows an upper trough will be exiting the area on Wednesday
night as surface high pressure builds across the area. This will
keep dry weather across the area along with mild temperatures
through late Friday night as strong ridging builds aloft and
passes gradually passes east of Indiana.

By early Saturday morning the ridge is well east of Indiana and a
warmer SW flow of air will be in place across the Ohio Valley.
European model (ecmwf) shows another deep trough entering the plains states along
with another cold front poised to sweep through the Ohio Valley
on Saturday and Sunday. With excellent Gulf flow ahead of the
front and good forcing in place...pops suggested by superblend
appear reasonable.


Aviation /discussion for the 211800z ind taf update/...

IFR conditions are expected to continues at ind. Drizzle and fog
resulting in ceilings under 1000ft are expected to persist.

Previous discussion below

/discussion for the 211800z tafs/...

Issued at 1237 PM EST sun Jan 21 2018

LIFR conditions are expected at laf...IFR conditions will be found

A warm front in place across laf...oik to north of mie
will continue to be the focus for dense fog over the next several
hours. Warm air advection over snow pack will continue to result
in dense fog through the afternoon.

Conditions may improve to IFR at all locations later today as the
warm front is expected to gradually lift northward as low
pressure and cold front approaches front the west. Rain showers
and IFR/MVFR conditions are expected on Monday morning as the
cold front approaches. Time heights and forecast soundings show
excellent lower level moisture and ample lift.


Ind watches/warnings/advisories...none.



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