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Area forecast discussion 
National Weather Service northern Indiana
556 am EST Sat Feb 6 2016

issued at 523 am EST Sat Feb 6 2016

Colder air and snow showers will dominate the upcoming work week
with many locations seeing accumulating snowfall Monday through at
least Wednesday.


Short term...(today and tonight)
issued at 523 am EST Sat Feb 6 2016

Upper level trough will quickly move through today. Little in the
way of deep moisture being seen with mainly middle/high clouds and a
few pockets of stratus/ground fog. More extensive cloud deck will
move in this morning to bring partly to mostly cloudy skies. Bulk of
deepest moisture and any light precipitation potential should remain north
of the area. Skies will begin to clear this afternoon mainly
southeast...allowing for temperatures to climb to near or just above 40. Clouds
may linger longer in northern areas which will keep highs in the
middle to upper 30s.

Upper level ridging will continue with low level flow continuing to
pump in somewhat warmer air. As one trough leaves to the east
another will quickly move in from the west later tonight...mainly
increasing cloud cover once again.


Long term...(sunday through friday)
issued at 523 am EST Sat Feb 6 2016

Triple ulvl jetlets on order of 140-180kts punch through northern
periphery of gradually expansion of western Continental U.S. Ridge today through
Monday...culminating in extreme amplitude trough base across southern
Great Lakes by 12 UTC Tuesday with slight negative tilt into southward
dropping polar origin vortex. This setup should aid in longevity of
surface Reflection/Lake aggregate troffing that bodes well for multi
day les event. In meantime...pre system warm air advection Sunday with modest middle
level Theta-E tongue that is initially more downstream displaced of
deepening system. Notable high sub cloud condensation pressure
deficits suggest little probability of msrb quantitative precipitation forecast. Continued mix mention as near
surface snow melt rate high with shallow surface based warm tw. System
acceleration into Sunday night suggests increasing chances/amounts
across eastern County Warning Area as reflected in pops/qpf. Have greatly reduced
snow accums however especially eastern County Warning Area where prolonged mix/wet
ground to offset accums especially prior to 06 UTC Monday. Succinct middle
level wrapped cva/respectable moisture curl impinging on County Warning Area by
daybreak Monday could bring bursts of accumulating snow for Monday am
commute. Extreme cold air advection plus dynamic cooling effects/prolonged middle level
height falls to quickly transition to all snow early Monday am.
Additionally have lowered maximum temperatures on Monday as diurnal range to
remain well squelched. Raised probability of precipitation for Monday Sans timing though upward
nudge to 12-18 UTC accums over prior in attempt to afford hint of
temporal resolution. Low static stability could portend to
mesobeta/Gamma banded enhancements though at dy3 beyond scope of
more than passing mention for now. As les setup ramp considerably
Monday night synopyic moisture enhancement to aid in dgz depth
though at present model profiles lack extreme supersaturation.
Height of les event/lake induced parameters Tuesday into early Tuesday
night. For now have continued trends of raising probability of precipitation sig in les
favored area midweek...with similar albeit trailing indications in
slr/accums given mesoscale conditionals. Suspect long duration advection
to be considered in future. Eventually midatl cylclogenesis lends
lysis of lake aggregate trough with gradual diminishing moisture
depth/lake eql with a more shallow dgz extending into subcloud region
for lesser accumulate rates Wed/Thu. Continued hints of clipper system Friday
with some lake response thereafter. However expect response not Akin
to latest given rapid southeast overtake of Arctic ridge into Sat.
Ec still hinting at strong southern stream system about valetines
day with surface low track into Ohio Valley. Northward moisture
flux/open Gomex atop Arctic airmass will need to be monitored for
possible sig synoptic snow event...with caveat of a slower/more
northern track affording potential ice swatch.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 553 am EST Sat Feb 6 2016

Little more than high clouds has allowed both taf sites to drop
into MVFR range due to haze/fog as low level moisture slowly
increases. Any fog should quickly dissipate shortly after 12z with
high clouds dominating the skies through at least this evening
before ceilings slowly begin lowering in advance of the next

Winds will become southwesterly with time and remain around 10
knots through the period.


Iwx watches/warnings/advisories...


short term...Fisher
long term...Murphy

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