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Area forecast discussion 
National Weather Service northern Indiana
411 PM EST Sat Nov 22 2014

Synopsis...
issued at 947 am EST Sat Nov 22 2014

The combination of an upper level disturbance and warmer air
moving back into the region will result in intermittent rain
today. Rain will become more widespread tonight with temperatures
staying well above freezing. Highs today will climb into the middle
and upper 40s. Low temperatures tonight will range from 40 to 45.

&&

Short term...(this evening through sunday)
issued at 409 PM EST Sat Nov 22 2014

The cold air that has been over the area for more than a week has
finally retreated north...with mild air spreading north. Showers
were continuing to develop north of a warm front that was still
over southern Indiana this afternoon as mild air was overriding the
cooler air. Showers should continue tonight...especially as a weak
short wave moves northeast across the area per 12 km NAM. There is
expected to be a Little Break with the showers between systems late
Sunday morning...with showers redeveloping during the afternoon as
another wave moves north. Temperatures will be much warmer than last
night...and will stay above freezing...so no ice is expected
tonight.

&&

Long term...(sunday night through saturday)
issued at 409 PM EST Sat Nov 22 2014

Little substantive changes with respect to ongoing forecast. Focus continues on
moisture flux convergence/plume advection as shortwave energy ejects
from arklatex 12 UTC sun to lower Ohio Valley by sun evening. 8 g/kg
1000-850 mb layer a bit farther northward...now lapping at southern County Warning Area Sun
night with Pivot Point over southeastern County Warning Area inadvof surface boundary Monday am. Deep
layer ascent fortified by intense 150-200m/12 hour hfc lifting northward
through County Warning Area Sun night early Sun night with area of enhanced quantitative precipitation forecast
lifting northward through County Warning Area. Also given magnitude of convergence ahead
of surface fnt and available moisture have ramped probability of precipitation somewhat into Monday am
as well...followed by sharp drop in dy3 afternoon probability of precipitation as dry slot wraps
into County Warning Area from SW. Extreme 25mb/3 hour cross frontal fall/rise couplet
along with quickly ramping wrly 60-70 knots 925 geographic flow portends to
needing hir gusts espcly along Lakeshore with gale watch needed for
nsh waters...holding gust below Wind Advisory levels at this time for
Berrien/LaPorte. While surface frontal timing consensus nudges a bit
quicker...maintained prior ptype changeover timing given negative
ice introduction with dry slot...and deepening of cold air
sufficient for mix/changeover still appropriately lagged.
Thereafter...modest les response expected in wake of system lifting
northeastward to Canadian with best focus Tuesday...waning into Tuesday night. Les
parameters continue to present rather lackluster with lake/800 mb thermal
differentials into the upper teens...unimpressive supersaturation
and depth/cohesion of dgz...to keep amounts in check. Models diverge
on maintenance of vigored shortwave per WV imagery near
50n/140w...favor emcwf with more recognizable clipper system into
western Great Lakes for light snow event...Wednesday aftn/night. Again minor les
into Thursday with primary focus leaning to coastal cyclongenesis off eastern
coast of fla as longwave trough deepens over cntl Continental U.S....shifting eastward
through midweek.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 133 PM EST Sat Nov 22 2014

The cold air that has been over the area for more than a week has
finally retreated north...with mild air spreading north. Ceiling/visibilities
have improved...especially at FWA where conditions had improved to
VFR. Showers were continuing to develop north of the warm front
that was still south of the terminals. Expect showers off and on
during the taf period as warm air overrides cooler air. A weak
short wave should also bring a chance for showers late tonight and
early Sunday.

&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...gale watch from Monday morning through late Monday night for
lmz043-046.

Small Craft Advisory until 10 PM EST this evening for lmz043-046.

&&

$$

Synopsis...skipper
short term...skipper
long term...Murphy
aviation...skipper



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