Flooding in Indiana, April 16 to 30, 2019

Area Forecast Discussion
National Weather Service Paducah KY
523 PM CDT Tue Apr 16 2019

.UPDATE...
Issued at 519 PM CDT Tue Apr 16 2019

Updated Aviation discussion for 00Z TAF Issuance.

&&

.SHORT TERM...(THIS EVENING THROUGH Wednesday NIGHT)
ISSUED AT 228 PM CDT TUE APR 16 2019

Satellite showing mainly high clouds moving over our area for the
next 24 hours or so. Deeper moisture is forecast to start
streaming northward out of the Gulf into the Texarkana area
tomorrow morning which will help fuel thunderstorms over the
southern Plains tomorrow. We should be dry into early tomorrow
evening.

The storms will increase in coverage during the day over the
southern Plains and likely congeal into an MCS tomorrow night.
The MCS should be weakening as it moves into our area early
Thursday.

The exact evolution of convection tomorrow and tomorrow night
will have a big impact on Thursday. Again, expect a weakening MCS
to move into southeast Missouri after midnight tomorrow night.
The best chance for severe looks to be during the morning and
early afternoon on Thursday. During that time, a 850 wind max is
forecast to move up from Arkansas on most models. Lapse rates are
around 6-6.5 between 850 and 500h with CAPE values less than 1000
J/kg. Prospects for severe are low, but not zero. This seems to
follow current SPC thinking of a slight risk on Thursday over the
southern sections.

Precipitation amounts. Looking at GEFS plumes, NBM, and other data
suggests that 1.5-2.5 inches will be the mean across much of the
area with slightly less over the northern portions.

.LONG TERM...(Thursday THROUGH Tuesday)
ISSUED AT 228 PM CDT TUE APR 16 2019

As compared to the last 3 days of model forecast trends of the
ECMWF, GFS, NAM, and Canadian, the forecast focus of the last 12-18
hours has been shanghaied toward a more progressive phasing of the
northern and southern trough over Missouri Thursday night, with a
translation of the trough into the lower Mississippi Valley. This
accelerates eventual north-south trough axis through the area
approximately 6-9 hours earlier, shortening the time of
lift/instability across the area.

Do have to admit that the ECWMF did offer at least one solution with
the low over or south of the WFO PAH forecast area this past
weekend.

However, even the latest NAEFS/GEFS Ensemble guidance suggest that
the impact on heights, winds, moisture, etc., is not as anomalous as
earlier depicted for Friday over the WFO PAH forecast area.

This change in direction has been in sharp contrast of earlier
forecast output and discussions presented by this forecaster, but
have to concede from the latest ensemble and deterministic model
runs that although dynamic, instability for any thunderstorm
development or hail production has become almost negligible of
Friday now.

This will not mean that scattered showers will be any less than
previously forecast, but most of the instability and omega (lift)
will remain in or below the cloud layer. Still anticipate some wind
gusts, but with lessening moisture within favored hail growth zone,
sub-severe hail production is now even out of the picture for midday
Friday.

Sharp ridging dominates over the weekend, providing warm and ideal
weather.

Several minor shortwaves over the western U.S. dampen the
ridge and place the WFO PAH forecast area in southwest flow by
Monday morning. A weak, baroclinic impressed surface slowly moving
frontal boundary between and upper Midwest/Great Lakes ridge and
southeast U.S. ridge. With the western Gulf of Mexico open, minor
waves rotating around the base of an upper trough centered over the
WFO PAH forecast area Monday and Tuesday, periodic showers and a few
thunderstorms can be expected Monday afternoon through late
afternoon Tuesday.

Another ridge axis is expected to dominate the area through the
middle and latter part of next week, drying and warming the region
again.

&&

.AVIATION...
Issued at 519 PM CDT Tue Apr 16 2019

Scattered to broken high clouds are expected in a warm advection
environ...with south to southwest winds gusting during the
daytime hours into the 20s kts, perhaps approaching 30 kts at
times tmrw pm. Low VFR diurnal bases may develop during the heat
of the day as well, but should remain scattered.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.

&&

Hazardous Weather Outlook
National Weather Service Paducah KY
312 PM CDT Tue Apr 16 2019

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-
100-107>112-114-171000-
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-
312 PM CDT Tue Apr 16 2019

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

.DAY ONE...This Afternoon and Tonight

No hazardous weather is expected at this time.

Check the latest warnings and statements for information about
river flooding.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Thunderstorms are possible Wednesday Night through Thursday Night.
There is a slight risk of severe thunderstorms mainly Thursday
morning into the afternoon south of a line from Poplar Bluff
Missouri, to near Paducah Kentucky, to Elkton kentucky. Locally
heavy rainfall is the main threat with some damaging winds
possible with the stronger storms.

A chance of thunderstorms is forecast Monday and Tuesday
of next week. Locally heavy rain and lightning will be the primary
hazards.

Check the latest warnings and statements for information about
river flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

PS