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fxus63 kiwx 171040 
afdiwx

Area forecast discussion
National Weather Service northern Indiana
640 am EDT Thu Oct 17 2019

Synopsis...
issued at 316 am EDT Thu Oct 17 2019

Dry and cool today and tonight followed by warming temperatures and
sunshine Friday and Saturday. Highs this afternoon will range in the
low to mid 50s, warming to the mid 50s to lower 60s Friday afternoon
and low to mid 60s Saturday.

&&

Short term...(today and tonight)
issued at 316 am EDT Thu Oct 17 2019

Continued dry entrainment within subdued lake based low level
thermal trough had eroded lake based showers overnight and confined
now to immediate wcntrl Michigan shoreline. However residual moisture
trapped below frontal thermal inversion points to diurnal based
resurgence of lake sourced stratocu inland of which hold back temps
again.

Low level ridge axis remains west overnight but with moderating low
level thermal trough aloft. Sfc ridge position along with
clear/mostly clear skies and decoupled sfc layer will allow temps to
plummet to aob freezing for most Sans Lake belt counties where lake
stratocu may linger.

&&

Long term...(friday through wednesday)
issued at 316 am EDT Thu Oct 17 2019

Robust warm advection aloft Friday as flow backs swrly ahead of
bifurcated upper wave lifting through the cntrl/nrn plains. Sfc
response will lag somewhat as sfc ridge slower to exit east yet
still a Cat or better warmer than this aftn.

Thermal ridge peaks momentarily Sat ahead of rapidly weakening swwd
trailing frontal zone tied to more vigorous nrn stream SW
disturbance lifting into wrn on. Will again downplay precip chances
here considering lack of leading moisture return and collapsing
upper support.

Much more formidable system spins up in wake of lead wave sun over
South Dakota along with a robust wrn Gomex traced return moisture tongue
working through the wrn Ohio Valley by Mon ahead of strong ewd
shifting frontal zone. Can't rule out some thunder potential east
half in proximity to better low level Theta-E ridging however
diluted mid level lapse rates likely limit said potential.
Nonetheless late Mon period bears continued scrutiny given the
season, presence of near 100kt mid level jet overhead and degree of
warm sector cloud contamination in regards to severe potential.

Thereafter brief/tempered Post frontal cold advection burst and
windy wx follows Tue-Wed.

&&

Aviation...(for the 12z tafs through 12z Friday morning)
issued at 640 am EDT Thu Oct 17 2019

Scattered-broken lake-enhanced stratocu will continue to be the primary
aviation concern today. Latest guidance (supported by surface obs)
continues to trend slightly drier and higher with ceilings.
Expect primarily VFR through today but some brief high-end MVFR
may still be possible by late morning as a shortwave approaches
the area and flow veers slightly. Diurnal heating should promote
slow rise of ceilings through the day with increasing subsidence
and dry air gradually scattering low clouds tonight.

&&

Iwx watches/warnings/advisories...
in...frost advisory from 2 am EDT /1 am CDT/ to 9 am EDT /8 am CDT/
Friday for inz004>009-012>018-020-022>027-032>034.

Michigan...frost advisory from 2 am to 9 am EDT Friday for miz078>081.

Ohio...frost advisory from 2 am to 9 am EDT Friday for ohz001-002-004-
005-015-016-024-025.

Lm...Small Craft Advisory until 4 PM EDT this afternoon for lmz043-
046.

&&

$$

Synopsis...T
short term...T
long term...T
aviation...agd



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