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Area forecast discussion 
National Weather Service northern Indiana
132 am EDT sun Oct 4 2015

issued at 731 PM EDT Sat Oct 3 2015

Low pressure over the southeastern U.S. Will continue to cause
occasional rain in our area overnight... especially across
Northwest Ohio and Northeast Indiana. Some drizzle may linger
north of Route 30 Sunday morning... otherwise dry weather and
warmer temperatures are expected for the final day of the weekend.
Temperatures will slowly rise overnight into the lower 50s by dawn
Sunday...with highs Sunday afternoon in the middle to upper 60s.


issued at 731 PM EDT Sat Oct 3 2015

Strong veering low/middle level winds on kiwx vwp indicative of warm air advection
and associated uvm while water vapor showing sub-tropical
moisture streaming northwest from the Atlantic through South Carolina
northwestward into the central Great Lakes. Combination of these
features was resulting in bands of rain continuing to develop
across the County Warning Area early this evening. In addition a more substantial band
of rain extending along an inverted trough from eastern Kentucky north to
Central Lake Erie is forecast by latest hrrr to move west into our County Warning Area
overnight. Thus... have increased probability of precipitation across the area for
tonight. Warm air advection of nearly saturated low levels should result in temperatures
slowly rising overnight but had to knock down lows a few degrees
based on temperatures starting off the period this evening.


Short term...(this evening through sunday)
issued at 343 PM EDT Sat Oct 3 2015

Persistent upglide/moisture advection on i300k surface leading to
lowering ceilings east-west across County Warning Area. Currently markedly stronger band of
isent lift lifting nwwd into northwestern County Warning Area and will cover with pre-
first period. With time...flow along isent surface to wane overnight
as ridge centroid just east of James Bay fills and sags southward and SC
coastal low/associated with southwestern Georgia middle level vortex weakens as Cat 4
Joaquin accelerates northeastward...tracking SW-west of Bermuda Sunday per
latest NHC forecast. Probability of precipitation wane to slight chance by daybreak. Though have
continued mention of dz potential across northern third County Warning Area Sunday as
light uvm associated with i295k pressure gradient/cross flow currently
into middle Ohio Valley lifting nwwd. Lift should occur within well
developed deep saturated stratus layer per prior/well perturbed
boundary layer this evening/Erly tonight. Non diurnal with temperatures near
steady/slowly rising per low level warm air advection through daybreak. Concerned
that depth/breadth of stratus across southern Great Lakes to limit
am insolation and squelched maximum temperatures on sun slightly...though not
as cool as met guidance. Suspect only far southeastern County Warning Area to breakout
sufficiently to reach near 70.


Long term...(sunday night through saturday)
issued at 343 PM EDT Sat Oct 3 2015

An upper level ridge will temporarily build upstream before a
broad upper trough gradually amplifies late this week. Ahead of this
amplifying trough...temperatures will moderate during the middle of
the week with highs warming well into the 70s. Raised highs a
little during the middle of the week as 850 mb temperatures rise
to between 10c and 13c per GFS. Otherwise...kept chances for rain
Thursday into Friday as short wave energy in northwest flow aloft
may be able to generate some showers. Temperatures will be cooler
again for this upcoming weekend.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 132 am EDT sun Oct 4 2015

IFR/LIFR conditions will persist through the early morning as
moisture-laden inverted surface trough swings through the area.
Slow improvement expected thereafter as best forcing and moisture
is shunted northwest. Filtered insolation and weak dry air
advection should allow for transition to VFR by later today though
confidence in exact timing is low...especially at ksbn. Pushed
back timing of improvement a bit based on latest forecast
soundings and MOS guidance but upstream observation are highly variable
and earlier improvement still possible.


Iwx watches/warnings/advisories...
Lm...Small Craft Advisory until 5 am EDT early this morning for



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

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