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Area forecast discussion 
National Weather Service northern Indiana
630 PM EST Friday Feb 5 2016

issued at 222 PM EST Friday Feb 5 2016

Near to above normal temperatures will dominate through Sunday
with little or no measurable precipitation expected. A return to
more winter like conditions will arrive beginning Sunday night
and lasting into Wednesday as colder air builds south across the
Great Lakes. Periods of snow showers will be common for much of
this time period...especially downwind of Lake Michigan over
northern Indiana and southern Michigan.


Short term...(this evening through saturday)
issued at 222 PM EST Friday Feb 5 2016

Pesky cloud cover slow to erode within ll thermal trough pivoting eastward
across the area this afternoon. Upstream advt component to the follow weakening
within ll ridge axis however drier air is entraining and suspect
west/Sundown western/central areas will clear out as diurnally driven SC
decays. However any clearing expected to be short lived as middle clouds associated/west
secondary upstream SW driving into northwest Iowa works eastward overnight. Thus
will follow an even MOS guidance split for mins.

Btr chances for at least partial insolation...especially Friday am and west/weak warm air advection
aloft expect we will btr maximum temperatures as compared to today.


Long term...(saturday night through friday)
issued at 222 PM EST Friday Feb 5 2016

Mild weather to start the period ahead of southeastward advg potent northern stream SW
amplifying southeastward out of Canada. Some penchant exits for rain/snow rain showers
to develop central/east Sun afternoon within emerging rtn follow moisture plume yet
will hold west/implied slwr gridded timing fvrg Sun night. Thereafter
centroid of vigorous 700 mb-5 circ to settle overtop the area on Monday
as fvrbly aligned Cross Lake Michigan ll follow develops within increasing ll
thermal troughing. This will yield a pronounced lake enhanced snow
event starting Monday night and lasting through Tuesday night if not Wednesday.
However placement qn/S remain coinciding west/as yet still considerable
spread aloft especially west/southward extent of possible phasing of Arctic stream
disturbance over Hudson Bay. Regardless 00-12z trends are more
progressive aloft and deemed more correct in light of expected addnl
upstream disturbances translating through the follow of which will be
followed today.

Best overlap of system associated middle level moisture...lake moisture flux and follow
trajectories fvrs highest probability of precipitation west half Monday night and north half
Tuesday/Tuesday night. Cross overlap of potential snow bands portents some
form of highlites will be needed in coming days. Otrws weak clipper to
follow on Thursday and reactivate lake effect Thursday night-Friday before the follow
backs around ahead of next more potent looking disturbance next weekend.

Well above normal temperatures through Monday will turn sharply colder
thereafter through the remainder of the period.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 619 PM EST Friday Feb 5 2016

Weak low/middle level theate ridging and weak low level convergence
with surface trough tracking across the area has been sufficient for
occasional flurries across northern Indiana late afternoon/early
evening. Back edge of MVFR conditions/flurries should clear ksbn
shortly after 00z...and should move across kfwa over the next few
hours with some flurries and the possibility of brief MVFR ceilings
through 02z. Weak anticyclone building in from the west will
result in mainly VFR conditions through the remainder of the
period. West winds immediately behind this surface trough will back
southwest overnight...with southwest winds of around 10 knots
expected for Saturday afternoon.


Iwx watches/warnings/advisories...


short term...T
long term...T

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