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Area forecast discussion 
National Weather Service Indianapolis in
617 am EST Friday Nov 28 2014

the aviation section has been updated below.


issued at 332 am EST Friday Nov 28 2014

High pressure will remain in control over the area through tonight.
This will result in dry but cold weather for Indiana. The high will
begin to drift east of Indiana later today. This will allow warmer
southerly flow to return to central Indiana in addition to chances
for showers as first a warm front lifts north over the
area...followed by a cold front Sunday night. Dry and cold weather
will return to the area behind the front on Monday night. Then
slowly through middle week temperatures will warm back to normal values
for this time of year. Next chance for precipitation will be
Thursday and Friday as a system from the plains moves into the area.


Near term /today/...

Issued at 332 am EST Friday Nov 28 2014

Short term guidance did not have a very good handle on the
flurries/borderline light snow showers which occurred over central
Indiana for most of Thanksgiving day and night...and have since
exited the region. Knowing this...and seeing the hrrr and sref
developing light precipitation returns moving into central Indiana from
Illinois early this morning...seriously considered putting in at
least a mention of flurries. As is customary with these type of
light wintry precipitation situations the rest of the short term guidance
is showing nothing but completely dry and partly cloudy sky
conditions today. Based on trends does not appear
these returns are making it to the surface so will refrain from even
putting flurries in the forecast at this time. However will need to
pay close attention through early this morning to see if flurries or
even -sn needs to be included in the forecast.

Otherwise...after this morning/S potential for flurries...the rest
of today looks fairly benign as surface high pressure begins to
shift east of the region. Skies partly cloudy across the south to
mostly cloudy for far northern counties as this area is closer to an
upper wave that will be moving through the Great Lakes. Blend of
guidance seems reasonable for highs 33 (northeast) to low 40s
(southwest cwa).


Short term /tonight through Sunday night/...

Issued at 332 am EST Friday Nov 28 2014

Tonight dry and cold conditions will prevail. Only difference is the
lows will actually be closer to normal thanks to the change to
southerly low level flow on the backside of the high pressure.

Temperatures will just keep on climbing right through this weekend
as strong warm air continues to advect into the region as a surface
warm front lifts north over the area on Saturday. Models have been
hinting at some weak chance for showers associated with this feature
and seem to be in agreement with at least some very light precipitation
possible beginning Saturday afternoon and continuing through the
weekend with very weak chances until a cold front moves through on
Sunday night. This latter portion of the weekend appears to have the
best chances for precipitation considering the forcing with the front and
higher precipitable waters and moisture. Felt confident enough to increase probability of precipitation to
at least widespread chance with even likely probability of precipitation across the
southeastern portion of the County Warning Area Sunday night.

As for temperature over the weekend leaned toward the warmer mav
guidance and even bumped up highs a degree or two based on very
strong warm air advection. And actually increased lows slightly for
same reason...and also factored in chances for precipitation and cloudy
skies...especially for the latter half of the weekend. Highs Sat
upper 40s to middle 50s...for Sunday upper 50s to low 60s. Very
impressive considering normal highs are middle 40s.


Long term /Monday through Thursday/...

Issued at 332 am EST Friday Nov 28 2014

A front south of Indiana and an upper wave moving through will keep
chances for a mix of rain and snow in the forecast for Monday...but
these chances will decrease as the front sinks south and the wave
moves off to the east. Dry weather is then expected Monday night
through Wednesday night with high pressure moving across the area.
Temperatures will remain below normal during this time. Models are
showing some variability from Wednesday on and with a fairly
progressive pattern there is little to key in on so will just accept
initialization...yielding small chances for rain Thursday with a
warm up.


Aviation /discussion for 281200z taf issuance/...

Issued at 615 am EST Friday Nov 28 2014

Expecting mostly VFR through the period. Winds will increase and
turn out of the south today with gusts around 20 kts or so this
afternoon at all sites but kbmg. Should see mainly middle level
ceilings today with some potential for MVFR to develop near the end
of the taf period as the next wave approaches. Looking at upstream
observations may include a tempo group for MVFR conditions with
light snow at klaf but will leave this out elsewhere as it could
stay north of the other sites.


Ind watches/warnings/advisories...


near term...smf
short term...smf
long term...cp

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