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Area forecast discussion 
National Weather Service northern Indiana
657 am EDT sun Jul 5 2015

issued at 325 am EDT sun Jul 5 2015

High pressure over Indiana and Ohio early this morning will move
east to New England tonight as a weak low pressure systems lifts
northeast from Kentucky to Ohio. This system will cause some high
cloudiness over eastern portions of our area today and tonight...
otherwise fair weather and a slow warming trend will continue for
the next couple of days. Temperatures will be near normal for middle
Summer with highs today in the lower and middle 80s and lows
tonight in the lower and middle 60s. The warming trend will come
to an end on Tuesday as a cold front moves east across the area...
likely accompanied by showers and possibly a few thunderstorms.


Short term...(today and tonight)
issued at 325 am EDT sun Jul 5 2015

Fog limiting visibilities across much of the area this morning... however
based on observation and webcams... visibility restrictions don't appear to be
significant and with moisture quite shallow doubt it will get much worse
so plan not to mention fog in todays forecast.

Low over Kentucky this morning expected to lift slowly NE into the upper
Ohio Valley today/tngt. Cirrus shield northwest of the low was spreading
into southeastern portion of the County Warning Area and should limit sunshine somewhat
across the eastern portion of the County Warning Area today. Otrws... heights will
continue to slowly rise across most of the County Warning Area today in response to
ridge aloft from WI-MO moving east ahead of rather strong trough moving
east-southeast into the northern plains. This ridge and associated dry/stable
airmass will provide another day of fair weather across our area with a
continued slow warming trend. Decent insolation even in the east
through cirrus filtered sunshine should allow for boundary layer
diurnal heating/mixing up to 850 mb once again today resulting in
afternoon highs a few degrees warmer than yesterday... in the l-m80s.
Radiational cooling conditions tonight not expected to be as
strong as past few nights... but light winds and little cloudiness
should allow temperatures to fall back to near seasonal normals in the


Long term...(monday through saturday)
issued at 325 am EDT sun Jul 5 2015

Only a few minor changes through the long term period. Monday still
appears to be the warmest day of the period with ample sunshine
anticipated in between a cut-off pv anomaly lifting NE into the
eastern Ohio/Tennessee valleys and a cold front approaching the upper
Midwest. Dampening middle-upper level trough into the upper
lakes/Ontario still on target to force this slowing frontal boundary
into the local area later Monday night-Tuesday. Shower/thunder
chances remain high given substantial pre-frontal moisture
advection/convergence...although coverage potentially limited given
northward displacement of better middle level flow/forcing. Not much/if
any severe risk although could see some locally heavy rain given
prognosticated deep/moist cloud layer (850 mb dewpoints nearing 15c).
Tuesday night into Wednesday will feature cooler/drier weather as frontal
boundary sags toward the Ohio River valley in flatter/quasi zonal flow
regime. Several convectively aided/smaller scale shortwave features
embedded in this weak flow support at least low chance probability of precipitation late
next week with frontal boundary in the vicinity.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 655 am EDT sun Jul 5 2015

Widespread br/haze across northern Indiana should burn off/mix out by late
morning... otrws VFR conditions expected at both terminals today and
tonight as ridging and dry airmass persist over the area. Some
potential for br across the area again late tonight as light surface
flow becomes a little more southerly resulting in weak moisture
advection into the area... but also a little stronger gradient wind
flow expected tonight so don't plan to introduce br to tafs at this time.


Iwx watches/warnings/advisories...


short term...jt
long term...steinwedel

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