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Area forecast discussion 
National Weather Service northern Indiana
724 am EDT Monday Jul 6 2015

issued at 403 am EDT Monday Jul 6 2015

An upper level ridge over our area will provide dry weather with
warm temperatures today. A cold front over the upper Midwest and
plains will move east across our area late tonight and Tuesday.
Showers and a few thunderstorms... are expected to accompany the
front as it moves through the area. Highs today will be in the
middle and upper 80s... with lows tonight mainly in the upper 60s
and lower 70s.


Short term...(today and tonight)
issued at 403 am EDT Monday Jul 6 2015

Shortwave will move east across the northern plains today to the upper
Great Lakes by Tuesday morning. The cold front associated with this system
currently located from central Minnesota-central Nebraska is expected to move
to the far northwest portion of our County Warning Area by the end of the short term
period. Low levels will moisten up today/tonight as southwesterly flow
overspreads the area ahead of the front... however middle levels remain
relatively warm/dry with a capping inversion around 5kft so no
showers/thunderstorms expected today... but increasing chances of
showers/thunderstorms spreading from northwest-southeast across the County Warning Area tonight as
moisture continues to deepen and forcing associated with the front
moves into the area. Diurnal instability will be waning overnight
so any threat of storms contain strong to severe wind gusts per Storm Prediction Center
marginal outlook in the far northwest would be this evening when some weak
diurnal instability and fairly large surface Delta Theta-E values
persist... but most models suggest timing of showers moving into
our area will be later so not too concerned about severe storms in
our area during the short term period.

As for temperatures... warm air advection and better gradient mixing will result in a
continuation of the warming trend today with highs expected to be
several degrees warmer than yesterday... in the M-u80s. Couple of
concerns for lows tonight... gradient mixing will hold temperatures up
much of the night but if showers do move in could see a quick
substantial drop. Also most models suggest front will move into
the northwest by 12z Tuesday with cold air advection in this area likely enhanced by winds
veering to off the lake. Leaned toward the faster/cooler solutions
in this portion of the County Warning Area.


Long term...(tuesday through sunday)
issued at 403 am EDT Monday Jul 6 2015

Shortwave lifting northeast through the upper lakes/Ontario will
force a weakening/slowing cold front through the area on Tuesday.
Moisture more than sufficient but some concern regarding associated
shower/thunder chances with this feature given north bypass of middle
level height falls and uncertainties with potential pre-frontal
trough/convective outflow. Held with likely probability of precipitation for now (sct-num
coverage) using a model consensus for timing...with better
coverage/intensity likely tied to diurnal cycle across east-
southeast zones where surface ambient temperatures likely near 80f. Locally
heavy rain possible with precipitable waters nearing 2 inches and a relatively
warm/deep cloud layer...although expect front to remain progressive
enough to limit the areal flood threat. 25-30 knots of southwesterly
flow in the low levels and potential for weak boundary layer
destabilization warrant spc's Tuesday afternoon marginal risk (iso wind
threat at best)...with cell growth/maintenance likely hampered by
warm middle levels and Post-frontal lag of needed deep layer

The above mentioned near surface portion of the front will likely
settle south of the local area in weak quasi zonal flow Wednesday
through Friday. This will result in a return to below normal
temperatures...especially Wednesday with a slight moderating trend
thereafter. Models continue to key in on a couple of convectively
modified vorts and subsequent elevated Theta-E surges that could
bring a soaking rain to the area later Wednesday-early Thursday and
another around Friday.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 720 am EDT Monday Jul 6 2015

Br impacting FWA with MVFR conditions at this time. Br not as extensive
across the area as yesterday morning and should burn off quickly this
morning. VFR conditions expected today with just scattered fair weather cumulus
and modest SW winds as a cold front approaches from the northwest. Cold front
expected to reach sbn near the end of the period accompanied by
rain showers and MVFR conditions. Ts also possible late tonight but given
diminishing instability... ts chances too low to add to taf at this time.
Impacts from the cold front should hold off at FWA until beyond this
taf period.


Iwx watches/warnings/advisories...


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

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