Flooding in Indiana, June 17 to 30, 2019

Area Forecast Discussion
National Weather Service Paducah KY
336 AM CDT Mon Jun 17 2019

.SHORT TERM...(Today through Wednesday night)
Issued at 330 AM CDT Mon Jun 17 2019

A boundary is still draped across/just north of the area and is
not anticipated to move much during the next 24 hours. Forecast
soundings show PW's continuing to run 1.5-2.0" today and tonight,
as an upper level wave opens up and lifts across the area. Recent
rainfall estimates in our north, combined with spotter reports,
show much of the I-64 corridor received 3 plus inches of rainfall
Sunday. Per collaboration with LSX/ILX/IND/LMK (thank you), have
issued an FFA for the northern half of southern Illinois, and
southwest Indiana. Any additional heavy or repeat rains over this
area will be particularly susceptable to causing flood issues.

In the wake of the flattening/departing wave, there should be a
diminishing trend to the Pops later Tuesday into Tuesday night,
that offers a relative pause in between two events. The next such
event metamorphisizes Wednesday-Wednesday night, as a potent upper
level wave drops out of the Plains states and heads into the
Mississippi River Valley. Here, it will encounter a warm/soupy
atmosphere, and it will bring with it an increasing shear profile
conducive to strong updrafts/thunderstorm growth, esp during the
peak diurnal heating hours of the day, when instability should be
at its maximum (but morning convection/cloud blow-off produces
some uncertainty in how unstable it does get that afternoon).
In summary, strong to severe storms are possible Wednesday
afternoon-evening.

.LONG TERM...(Thursday through Sunday)
Issued at 330 AM CDT Mon Jun 17 2019

The primary long term concern is the return potential for showers
and thunderstorms next weekend. Forecast confidence starts off
higher than average with relatively good model agreement Thursday
and Friday. More model variability lowers confidence heading into
next weekend.

Starting with Thursday morning, most model solutions are in good
agreement that the unsettled pattern will be coming to at least a
temporary reprieve as the low pressure system responsible for the
wet weather exits east through the Ohio Valley. In its wake, an
upper level ridge is forecast to build east and amplify from the
Great Lakes to the Gulf Coast by the weekend. Initially, this should
result in a return to dry weather for most of Thursday, Thursday
night, and even into Friday.

How long that dry weather sticks around is in question as model
solutions diverge over the weekend. Most model solutions are in good
agreement that the potential for showers and thunderstorms will be
on the increase by Saturday night and Sunday as upper level energy
over the Plains streams northeast in the southwesterly flow pattern
around the periphery of the upper ridge.

The period of greatest uncertainty ranges from Friday afternoon
through Saturday. During this time, the ECMWF and CMC keep mainly
dry conditions in place, while the GFS continues to indicate
weaknesses in the ridge that cause concern for at least isolated
shower and thunderstorm potential. The official forecast will carry
slight/small chances starting Friday afternoon and continuing
through Saturday, with better chances by Saturday night and Sunday.

High temperatures are forecast to warm from the lower and mid 80s on
Thursday into the upper 80s and perhaps near 90 degrees by Friday
and Saturday, tempered back into the middle 80s on Sunday with
increased sky cover and rain chances. Lows are forecast to warm from
the mid and upper 60s Thursday night to near 70 by the weekend.

&&

.AVIATION...
Issued at 330 AM CDT Mon Jun 17 2019

Diminished shower/storm activity during these pre dawn hours will
ramp up again during the daytime. Any breaks in the pre dawn
cloud cover will be conducive to still lingering high rh in the
sub boundary layer to develop low clouds/fog with restricted
flight categories in both cigs/vsbys, but this should be
patchy/sporadic with varying sky cover. The best chance of storms
and additional flight restrictions is during the heat of the day
this afternoon/evening.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Flash Flood Watch from 7 AM CDT this morning through Tuesday
     morning for ILZ075>078-080>083.

MO...None.
IN...Flash Flood Watch from 7 AM CDT this morning through Tuesday
     morning for INZ081-082-085>088.

KY...None.
&&

Hazardous Weather Outlook
National Weather Service Paducah KY
355 AM CDT Mon Jun 17 2019

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-
100-107>112-114-181000-
Jefferson-Wayne IL-Edwards-Wabash-Perry IL-Franklin-Hamilton-
White-Jackson-Williamson-Saline-Gallatin-Union-Johnson-Pope-
Hardin-Alexander-Pulaski-Massac-Gibson-Pike-Posey-Vanderburgh-
Warrick-Spencer-Fulton-Hickman-Carlisle-Ballard-McCracken-Graves-
Livingston-Marshall-Calloway-Crittenden-Lyon-Trigg-Caldwell-
Union KY-Webster-Hopkins-Christian-Henderson-Daviess-McLean-
Muhlenberg-Todd-Perry MO-Bollinger-Cape Girardeau-Wayne MO-Carter-
Ripley-Butler-Stoddard-Scott-Mississippi-New Madrid-
355 AM CDT Mon Jun 17 2019

This Hazardous Weather Outlook is for portions of southern
Illinois, southwest Indiana, western Kentucky, and southeast
Missouri.

.DAY ONE...Today and Tonight

While an isolated strong storm cannot necessarily be ruled out,
thunderstorms with heavy rainfall are the primary forecast
hazard. A Flash Flood Watch is in effect for northern portions of
southern Illinois and southwest Indiana. The Watch is along and
north of a line from Du Quoin, Illinois to Rockport, Indiana.
Refer to the Watch for additional details.

River flood warnings and statements should be referenced for updated
river flooding details.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Strong to potentially severe thunderstorms are forecast Wednesday
afternoon and evening. Damaging winds, including isolated
tornadoes, will be the primary severe storm hazards.

Storm chances wane Wednesday night and Thursday, before picking
up again Friday into the weekend. The better such chances will
hold off until the latter half of the weekend, with the primary
storm related hazards including heavy rain and lightning.

Details on continued river flooding are best referenced via the
updated river flood warnings and statements.

.SPOTTER INFORMATION STATEMENT...

Spotter reports of rainfall and flooding are encouraged today
through tonight. Spotter activation is possible again Wednesday.