Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 250710

Area Forecast Discussion
National Weather Service Northern Indiana
310 AM EDT THU AUG 25 2016

Issued at 157 AM EDT Wed Aug 24 2016

Showers and thunderstorms are likely today as a cold front moves
east across the area. Severe storms are possible this
afternoon...especially along and east of Interstate 69. Highs
today will be in the upper 70s to middle 80s, with lows tonight in
the lower to middle 60s.


.SHORT TERM...(Today through Saturday night)
Issued at 248 AM EDT Thu Aug 25 2016

Upr level trof over the nrn plains will move east to the upr grtlks
today and to Quebec tonight. Associated sfc cdfnt extending from
the upr grtlks to Mo early this morning will move east across our
cwa today. Rather fast mid level flow across our area will result
in strong (30-40kt) deep layer shear along the wk cdfnt. Question
is how much destabilization will occur today. Mcs which formed
near the cdfnt overnight was movg east across nrn/central IL attm
and will probably reach our area early this morning but should be
diminishing in intensity as instability wanes and llj weakens
toward daybreak. Still appears good potential for at least remnant
convection to move through nw portion of the cwa this morning
limiting destabilization before fropa there. On the other hand, SE
portion of cwa may have sufficient pre-frontal sunshine to allow
temps to reach the m-u80s this afternoon resulting in 2-3kj/kg
cape. This could allow svr storms to form in this area again this
aftn if convergence along front or outflow boundary is strong
enough to support development of deep convection. Very moist
airmass with pwat near 2" remains in place over the area which
will also support locally heavy downpours with any thunderstorms,
though appears storms will have sufficient motion to limit
flooding threat to just localized issues.

Post-frontal high pressure should build into the area tonight
providing fair wx after perhaps a few lingering showers/storms se
early. Temps should just cool back to normal with lows in the l60s
and highs in the l80s, warming slightly Sat as the ridge moves east
and wk waa develops. Ridging persisting across our area through
Saturday should cont generally dry wx though a low but incrsg threat
of showers/tstms movg into the cwa Sat aftn/night as another upr
level trough moves through the nrn plains resulting in considerable
convection to the west of the ridge across the ms valley which
may survive into the drier/more stable airmass associated with
this ridge.


.LONG TERM...(Sunday through Wednesday)
Issued at 248 AM EDT Thu Aug 25 2016

Upr ridge over the sern u.s. expected to weaken early next week
and grdly retrograde to the plains as an upr trof digs into the
west coast. This should result in temps at or slightly above
normal over our area with highs in the l-m80s and lows in the
l-m60s. Small chances for showers/tstms due to potential of wk
shrtwvs with accompanying mcs activity topping the dvlpg plains
ridge and psbly movg into the midwest.


.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 139 AM EDT Thu Aug 25 2016

At least 2 potential rounds of convection over the next 12 to 18
hours. with the first arriving at KSBN in the next couple of hours
as convection was moving east and northeast out of Illinois.
Extrapolation brings initial activity in after 8z and possibly
lingering for a few hours. Delay of a few hours at KFWA. Have
opted for VCTS for the moment and will amend after trends are
watched a bit longer to see exact impacts on airports.

Likely will be a lull around 12 for both sites before a cold front
moves in after 18z. Additional showers and storms may develop
along or ahead of this but exact coverage and intensity still
questionable so VCTS has been left with some adjustments to times
to allow for a break followed by the afternoon chances.

Once the front clear the area VFR conditions should prevail. Will
need to look at fog potential in later forecasts depending on
amount of rainfall and clearing Thursday night.


.IWX Watches/Warnings/Advisories...



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