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fxus63 kind 240645 
afdind

Area forecast discussion
National Weather Service Indianapolis in
245 am EDT Thu Aug 24 2017

Update...
the synopsis...near term and short term sections have been updated
below.

&&

Synopsis...
issued at 242 am EDT Thu Aug 24 2017

High pressure is expected across the area through the end of the
week. An upper level low may bring chances for precipitation to the
area by the early to middle parts of next week.

&&

Near term /today/...
issued at 242 am EDT Thu Aug 24 2017

Upper trough currently located over northeast Minnesota and
northwest Wisconsin will drop southeast through the Great Lakes
later this afternoon. A few ensembles suggest a small threat for
light showers over the far northern zones this afternoon as this
system brushes by. Model data in general suggest little, if any,
organized lift this far south with the upper trough, so will keep
the forecast dry today. There will probably be more in the way of
cloud cover today than there was yesterday.

Low level thicknesses suggest the GFS MOS highs for today look
reasonable, so little if any adjustments planned.

&&

Short term /tonight through Saturday night/...
issued at 242 am EDT Thu Aug 24 2017

Model data suggest a dry northwesterly upper flow will continue
across the local area during this period as a long wave trough
remain anchored over the eastern parts of the country. Dry weather
expected as surface high pressure slowly drifts through.

Progged low level thicknesses suggest the GFS MOS temperature
guidance looks good for the next couple of days, so any adjustments
will be minor.

&&

Long term (sunday through wednesday)...
issued at 220 am EDT Thu Aug 24 2017

It is looking more and more like there will be unsettled weather
next week associated with first, a slow moving upper Midwest trough
and low and later, possibly the remnants of Harvey.

Models and ensembles do agree on one thing, that it should be dry
through Sunday evening. Then, the 00z GFS is the fastest model to
bring quantitative precipitation forecast to central Indiana as it is the quickest to move an upper
Midwest trough and upper low and deep moisture to the Great Lakes.
As such, the GFS has quantitative precipitation forecast over our west Sunday night whereas the
others do not. The GFS also is quicker to overspread the forecast
area with quantitative precipitation forecast on Monday. The blend favors the GFS over the slower
Canadian and slowest Euro. Confidence in the slower majority is not
high enough to make any changes it.

The Euro is the one model that lifts the remnants of Harvey
northeast enough to get absorbed by the previously mentioned upper
trough. That said, it brings the bulk of the rain associated with
Harvey to the Appalachians. The other models move the upper trough
into Ohio by Wednesday. This would favor low pops for central
Indiana at best.

Confidence still not great with timing and or the evolution of
Harvey, so stay tuned.

Fairly extensive cloud cover and upper troughing favors continued
below normal temperatures which lends confidence to the blend with
its highs in the upper 70s and lower 80s.

&&

Aviation /discussion for the 24/06z taf issuance/...
issued at 1150 PM EDT Wed Aug 23 2017

VFR through the period.

Surface high pressure will be in control through the period, but a
weak upper wave will skirt the area to the north tomorrow, likely
resulting in scattered to broken stratocumulus development based
around 5kft. Winds through the period will generally be light and
variable. No significant obstructions to visibility anticipated,
although light MVFR fog briefly around daybreak cannot be completely
ruled out at the outlying sites.

&&

Ind watches/warnings/advisories...
none.
&&

$$

Synopsis...jas

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