Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Indianapolis in
657 PM EDT sun Sep 21 2014

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


issued at 232 PM EDT sun Sep 21 2014

An upper trough will exit the area tonight allowing clouds to move
out. High pressure will then build in and provide dry conditions for
most of the next week. Cool temperatures early in the week will
return to near average during the period.


Near term.../rest of this afternoon and tonight/
issued at 232 PM EDT sun Sep 21 2014

Clouds associated with upper trough continue to move south into
central Indiana early this afternoon. There are scattered showers as
well across northern Indiana and lower Michigan.

Clouds will continue to move into the area this afternoon as the
trough moves into the area. Expect bulk of scattered showers to
remain mainly north and east of central Indiana closer to where
better forcing is...but isolated showers or sprinkles may make it
into the area before 00z. For now with do not plan to include
but will keep an eye on it.

Clouds will continue during the evening with cyclonic flow and cold
advection...but this eases overnight so expect clouds to clear out.
With the clearing skies overnight and a colder airmass in place...a
cool night is in store. Went with a blend of model temperatures.


Short term.../Monday through Wednesday/
issued at 232 PM EDT sun Sep 21 2014

Focus is on temperatures. Models are similar so used a blend.

High pressure and a building upper ridge will keep the area dry and
generally mostly clear through the short term.

Met MOS looks too cold on Monday given expected sunshine. Went
closer to the warmer mav MOS. With mostly clear skies and light
winds Monday night...stuck close to mav MOS with good radiational
cooling expected.

For Tuesday...mav MOS looks to warm things up too fast...especially
given an easterly component to the low level flow. Cut mav by a few
degrees. For Tuesday night and Wednesday a model blend looks OK for


Long term /Wednesday night through Sunday/...

Issued at 145 PM EDT sun Sep 21 2014

Quiet weather is expected through at least Saturday night as the
European model (ecmwf) and GFS both agree that a broad area of high pressure will
remain over the eastern half of th United States...providing dry
weather along with seasonable temperatures. By Sunday the the GFS and
European model (ecmwf) suggest the high finally beginning to drift to the
west...and a surge of moisture along with an upper level weather
disturbance arrives in the Ohio Valley on Sunday afternoon. Have
included low chance probability of precipitation with this feature and it will be our next
best chance for rain.


Aviation /discussion for the 220000z taf issuance/...

Issued at 657 PM EDT sun Sep 21 2014

Would not rule out brief MVFR ceilings at ind and laf for the start
of the tafs...but more likely VFR with clearing after sunset. Winds
will die off quickly to northwest less than 10 knots after no later
than 01z. Tomorrow...high pressure will settle in over the terminals
resulting in clear skies and north winds less than 10 knots.


Ind watches/warnings/advisories...


near term...50
short term...50
long term....puma

Visit US at http://www.Weather.Gov/ind

Follow US on facebook...twitter and youtube at:

National Weather Service Glossary of Abbreviations