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Area forecast discussion 
National Weather Service northern Indiana
259 PM EST Monday Nov 30 2015

issued at 1239 PM EST Monday Nov 30 2015

Mostly cloudy skies expected today with high temperatures in the
middle to upper 40s. Rain showers will move in overnight with
rainfall totals less than quarter of an inch expected. Low
temperatures tonight will be in the low 40s.


Short term...(this evening through tuesday)
issued at 258 PM EST Monday Nov 30 2015

Continued dry easterly flow has kept our area dry today and will
delay the onset of precipitation this evening. Better push of moisture will
arrive after 00z as 850mb flow veers and advects 6 g/kg mixing
ratios into the County Warning Area. Scattered showers will move into the area with
this push...but with the better forcing to the northwest and the best
moisture southeast of our area...expect total precipitation to be less than
0.10" for most of the area. This is supported by the 16/17z rap/hrrr
which bring very little rain through the area overnight.

Surface dewpoints in the low 40s are currently located southeast of
the County Warning Area and will overspread the area into the evening. This added
low level moisture will bring with it areas of fog developing after
06z. Surface winds look to stay in the 5 to 6 knot range which will
keep the fog from becoming too dense. Although...if winds go calm
tonight...widespread dense fog is a concern. Increased probability of precipitation for the
first part of Tuesday to better reflect the slower progression of
this system. Expect most of the precipitation to be through the area
by middle-day tomorrow as the dry slot overspreads the County Warning Area.


Long term...(tuesday night through monday)
issued at 258 PM EST Monday Nov 30 2015

Precipitation chances will return on Wednesday as primary upper trough axis
and attendant/secondary surface trough swings east through the region.
Decent tropopause pressure advection with vorticity lobe wrap through...and
prognosticated ample deep layer moisture/cyclonic flow...warranted an
increase in probability of precipitation into northwest in/SW lower Michigan late Tuesday night into
Wednesday morning...and points east-southeast into the late morning/afternoon.
Higher probability of precipitation/coverage still anticipated in the north-northwest where some lake
enhancement is expected. Precipitation amounts will be light and more
showery in nature...with ptype mainly snow northwest to a mix of
rain/snow along/east of Interstate 69 given more marginal near surface
temperatures. Could see some light snow accums (<0.5") on mainly grassy
sfcs in Northwest Indiana/SW lower Michigan. Ridging aloft then builds
in thereafter will fair weather and gradual warming.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1239 PM EST Monday Nov 30 2015

Trended towards more pessimistic ceilings and visibility tonight
at kfwa with latest hrrr and rap suggesting the potential for
ceilings below alternate minimum tomorrow morning. There is some
potential for dense fog as well...but it appears winds may stay
just strong enough to keep widespread dense fog potential
suppressed. Took kfwa taf right to alternate minimum
thresholds and will let evening shift reassess fog/low ceiling
potential for 00z taf issuance. Kept ksbn at MVFR at this time...with the
lower ceilings/visibilities expected to stay east of the
terminal. Although...if the stratus deck advects 20 to 30 miles
further west than it is currently projected...conditions at ksbn
may reduce to IFR or alternate minimum as well.


Iwx watches/warnings/advisories...


short term...Bentley
long term...steinwedel

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