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Area forecast discussion 
National Weather Service northern Indiana
703 PM EDT sun Oct 4 2015

issued at 351 PM EDT sun Oct 4 2015

Partial clearing may allow some fog to form near daybreak...
especially along and south of Route 24. Lows overnight will fall
back into the lower 50s. Highs on Monday will be a bit
the middle 60s near Lake Michigan to the lower to middle 70s well


Short term...(this evening through monday)
issued at 349 PM EDT sun Oct 4 2015

Primarily concerned with br/fog potential late tonight. Pool of
hir/middle 50s dps over southeastern half of County Warning Area for elevated xover
temperatures...additionally widespread wetted ground...weakening surface
flow and middle/late afternoon clearing of stratus conducive for am
br development. While core of gradual southward sinking surface ridge through
upper Great Lakes remains north of County Warning Area...expect sufficient early
decouple amid surface based saturation to side with br formation over
stratus expansion/redevelopment. For Monday...initially was
concerned that temperature forecast a tad optimistic...but have shifted
180 given todays stellar recovery across southeastern half of County Warning Area where
stratus mixout has brought temperatures 20-25f hir over past 24 hours.
Given additional moderation of 925mb temperatures across County Warning Area...suspect
rather robust rebound after br mixout. Slightest upward nudge to
maximum temperatures Monday outside of notable Lake Shadow penetration inland
as surface ridge settles into i80/southern lakes corridor.


Long term...(monday night through sunday)
issued at 349 PM EDT sun Oct 4 2015

Initial challenges this period concern the mixing out of the cool
layer below frontal inversion. A cool northeast flow along with
recent rains have saturated much of the layer below the top of the
inversion. With waning autumnal solar radiation and a lack of
initial warm air advection...favor the cooler guidance including
the GFS for highs Tuesday. The warmest days of the week should be
Wednesday and Thursday ahead of the front. On these days...with
better effective mixing...highs both days should be near 75.
Overall models and guidance were still supporting a frontal
passage about Thursday night/Friday morning. The GFS appears to be
handling this pattern reasonably well...although there was still
quite a bit of spread from run to run. Precipitable water values
should rise to around 1.5 inches Thursday...which is very high for
October. Kept thunder out for now...but can not rule out a rumble
of thunder. Made some temporal adjustments to the front and
associated precipitation. Not much cold air will be able to spread
into the area behind this system late this week as return flow
should set up about 30 hours after frontal passage.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 658 PM EDT sun Oct 4 2015

Stratus/strato cumulus mixed out at FWA late this morning and at sbn
late this afternoon. Sbn remains closer to some strato cumulus and has a
better potential than FWA of redeveloping a low cloud deck early
tonight... though felt this threat was low enough to keep forecast VFR.
Low levels remain rather moist and with gradient decreasing
overnight as high pressure ridge over the upper Great Lakes sinks slowly
south... expect cross-over temperatures will be breached by 1-3f. Forecast
IFR visibilities at both terminals and appears there is some potential
for LIFR. Br expected to mix out by late Monday morning with VFR
conditions and light NE winds expected the remainder of the day as
weakening ridge continues to build S-southeast across the western Great Lakes.


Iwx watches/warnings/advisories...


short term...Murphy
long term...skipper

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