Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 271704

Area Forecast Discussion
National Weather Service Northern Indiana
105 PM EDT FRI MAY 27 2016

Issued at 403 AM EDT Fri May 27 2016

High pressure will remain nearly stationary over the southeastern
U.S. causing warm moist conditions across our area through the
Memorial Day weekend. Temperatures will remain well above normal
with highs in the lower or middle 80s and lows in the 60s. A low
chance of mainly afternoon through early evening thunderstorms
will continue into early next week.


.SHORT TERM...(Today and Tonight)
Issued at 403 AM EDT Fri May 27 2016

Deep southerly flow to continue over the region today with abundant
moisture but a lack of strong forcing for ascent. Water vapor and IR
imagery showing numerous weak MCVs embedded within widespread
convection and debris cloudiness across the Midwest. Spectral models
continue to struggle with convective details given more coarse
resolution and convective models remain overdone at times. Weak flow
and lack of strong short wave makes for difficult forecast with
respect to when and where thunderstorms will develop.

Regional radar mosaic showing area of showers moving northeast from
southern IL and IN at 08z. HRRR has a decent handle on this area and
brings it into far southwest around 12z with decaying/weakening
trends as it lifts north. Have middle range chance pops for this
area. Instability again shown by models to be in the 1500-2500 j/kg
range this afternoon. concern that debris cloudiness may be more
extensive today and may not see as much afternoon sun as on
Thursday. Continued with a low to mid chance pop this afternoon with
convective models again showing some development. Highs today should
still reach lower 80s with muggy conditions as sfc dewpoints remain
in the mid 60s. Lingering low chance pops tonight in the west with
deep moisture feed and any weak MCV could easily set off a few
storms. Lows will remain in the 60s.


.LONG TERM...(Saturday through Thursday)
Issued at 403 AM EDT Fri May 27 2016

Thunderstorm chances continue Saturday and Sunday as deep southwest
flow continues to pump moisture into the region. A few weak short
waves Saturday but stronger wave appears in the models for Sunday as
upper low lifts through the western Great Lakes and stronger short
wave lifts northeast over our area. 0-6km shear increases and
potential CAPES of 2k j/kg or greater if we partially clear. Will
see how this plays out as models have yet to impress in this regime.

Brief period of drying and subsidence appears likely for Memorial
Day behind departing short wave and building heights. This in part
to blocky pattern with tropical/subtropical low meandering over the
Carolinas as downstream ridging develops. Thunderstorm chances
return mid week as moisture plume returns in southwest flow as
another low moves across the northern CONUS.

Highs generally in the lower 80s during the period with lows in the
60s. Temps will trend a few degrees cooler by mid to end of week
with dew points also back into the 50s making it a bit more


.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 105 PM EDT Fri May 27 2016

Band of light showers resulting from weak disturbance lifting
northward through the area continues to weaken and is now north of
both TAF sites. Another wave moving up through central Illinois this
afternoon may have showers redeveloping in the KSBN vicinity so
will include a 3 hour window of VCSH to account for this. Otherwise
VFR through the period on south/southwest winds generally 10kts
or less.


.IWX Watches/Warnings/Advisories...


SHORT TERM...Lashley
LONG TERM...Lashley

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