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Area forecast discussion
National Weather Service northern Indiana
216 am EST Sat Nov 25 2017

issued at 723 PM EST Fri Nov 24 2017

A cold front is working its way through central Wisconsin at this
hour. Locally, wind gusts have increased a bit as a strong low-
level jet approaches from the northwest. Aside from a sprinkle
tonight, we anticipate dry conditions to prevail this weekend. Low
temperatures tonight will fall near 40. Saturday, temperatures
will be sluggish to rise into the mid-40s. This coming week, we
will monitor a few chances for light precipitation. Otherwise,
expect largely dry conditions with temperatures above normal.


Short term...(today and tonight)
issued at 212 am EST Sat Nov 25 2017

Latest surface analysis has cold front near the Illinois/in border and
will be moving across the forecast area this morning. Kiwx radar
indicating some weak returns ahead of the front which may result
in a few sprinkles or light rain showers and secondary short wave
dropping into Southern Lower Michigan this afternoon may do the
same in the northern County Warning Area. Otherwise...strong gradient behind the
front will have gusty northwest winds this afternoon. Cloud cover and cold air advection
will result in very little diurnal temperature recovery with near
steady temps of 45-50f. Surface ridging will build in from the
west tonight bringing clearing skies...diminishing winds...and
lows dropping into the upper 20s.


Long term...(sunday through friday)
issued at 212 am EST Sat Nov 25 2017

Surface high pressure building into the Tennessee Valley will provide
fair weather and seasonable temperatures to the region on Sunday.
Warming trend to begin the workweek as return flow develops over
the area in response to surface high moving east toward the
Carolinas. Impressive low level thermal ridge surging into the
mid-MS valley will have highs into the low-mid 50s Monday and
Tuesday. Progressive zonal flow across Canada will bring yet
another moisture starved cold front toward the area late Tuesday.
As with previous system...surface low detached well to the
north...northern Ontario this time...and providing little forcing
in support of precip chances. But many of the gefs members still
showing weak signal in support of small chance pops in the northwest County Warning Area
and blend carries this as well so will continue to leave in the
grids for now. Another system quickly follows with still plenty of
spread and run to run variability among the models and ensembles.
This has blend spreading pops out from Wed afternoon thru
Thursday night. Will ride with this for now and wait for better
consensus to fine tune. High pressure builds back into the region
to end the forecast period with dry weather and seasonable temps


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1233 am EST Sat Nov 25 2017

Surface cold front currently approaching the taf sites. Very
little moisture available so not expecting any impacts with the
front itself. However, postfrontal cold air advection will lead to a period of
lower ceilings later this morning. Some guidance, particularly the
NAM, still suggesting fuel alternate and possible IFR. This still
seems too aggressive based on upstream obs and lack of low level
moisture. Will hold with high-end MVFR for now but some brief fuel
alternate may be possible in the 11-14z period. Gradual lifting
and clearing expected through the day as drier air advects into
the area.


Iwx watches/warnings/advisories...
Lm...Small Craft Advisory until 1 PM EST Sunday for lmz043-046.



short term...Jal
long term...Jal

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