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Area forecast discussion 
National Weather Service northern Indiana
344 PM EDT Friday Jul 3 2015

issued at 339 PM EDT Friday Jul 3 2015

A few isolated showers or sprinkles are possible this evening for
areas south of Route 24. Otherwise..clearing skies can be expected
tonight. Mainly dry conditions will persist for Saturday and
Sunday as a ridge of high pressure affects the region. There is a
good chance of showers and thunderstorms again Monday night into
Tuesday as a cold front approaches. Low temperatures tonight will
drop into the middle and upper 50s. High temperatures on Saturday
will reach around 80...except in the middle 70s closer to Lake


Short term...(this evening through saturday)
issued at 339 PM EDT Friday Jul 3 2015

Quiet weather is expected for the 4th of July...with an upper
level ridge building overhead and surface high pressure below. As
a result...have mostly clear to partly cloudy skies across much of
the County Warning Area later tonight and Saturday.

Only fly in the ointment is the surface low shifting to the east across
Kentucky this afternoon. This has brought a few isolated
showers/sprinkles to the southern County Warning Area and a broken-overcast deck of high
clouds around 15kft to much of the area. NAM and host of other
models are overdoing probability of precipitation/quantitative precipitation forecast thus have stuck to using the
hrrr as it has done well with the more isolated nature of showers
today. With dry air in the low levels it seems pcp has failed to
make it far northward thus far...and expect it to stay that way this

With high pressure moving overhead...skies clearing...and
winds light/variable would expect some fog development late
tonight...but with drier airmass expected was hesitant to add
anything into forecast. If anything...thinking it will be more of a br
situation with visible 3-5 miles further to the south where there is a
bit more moisture.


Long term...(saturday night through friday)
issued at 339 PM EDT Friday Jul 3 2015

Disjointed upper level pattern will continue into Sunday. Another
northern stream vorticity maximum should weaken across the western Great
Lakes during the day Sunday while forcing with southern stream
trough generally remains south of the area. Moisture will be
limited and with local area likely split by forcing once again will
continue to keep this period dry. Some very low probability may
exist for an isolated shower to develop in the afternoon along lake
breeze boundary across Northwest Indiana...but not of large enough
confidence to insert mentionable probability of precipitation at this time.

Cut-off pv anomaly across the lower Ohio Valley may try to get
ingested back into northern stream late Sunday night into
Monday...but it still appears as though chances of showers and
thunderstorms will hold off until the Monday night/Tuesday
timeframe. No significant changes made to previous likely probability of precipitation for
this period. Overall severe potential looks to be on the low side
given expected unfavorable diurnal timing...meager middle level lapse
rates...and local area remaining on extreme southern fringe of
stronger forcing working across the northern Great Lakes.

Chance of showers/thunderstorms to continue Tuesday evening in
association with slowing frontal boundary...mainly southeast half.
Cooler conditions for Wednesday and Thursday with perhaps an
isolated shower/thunderstorm across the southeast as a weak middle
level trough may induce weak downstream low level thetae advection
in association with boundary in vicinity. Maintained idea of
previous forecast with better chances of showers and thunderstorms
Thursday/Friday as low level boundary makes a more aggressive
northward surge.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 142 PM EDT Friday Jul 3 2015

(for the 12z tafs through 12z Saturday morning)
issued at 703 am EDT Friday Jul 3 2015

A low pressure system moving through Kentucky is causing an
increase in cloud cover...with most areas this afternoon seeing
scattered clouds around 3-4kft and a broken-overcast deck around
15kft. As the low pressure system drifts southeast...expect a
decrease in cloud cover. Building high pressure will lead to
mostly clear skies by late evening...and brings the potential for
some fog development with nearly calm winds. At this
point...thinking kfwa has the best chance but do not see
visibilities dropping below 3-4 miles given incoming drier air.
For now kept 4sm br in for kfwa starting at 9z. Quiet weather/VFR
conditions continue through Saturday.


Iwx watches/warnings/advisories...


short term...mesoscale discussion
long term...marsili
aviation...mesoscale discussion

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