Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
426 AM EDT Tue Apr 14 2026

Day 1
Valid 12Z Tue Apr 14 2026 - 12Z Wed Apr 15 2026

...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS THE CENTRAL
L.P. OF MICHIGAN AND SOUTHEAST WISCONSIN...

...Great Lakes Region...

A Slight Risk for excessive rainfall remains in effect for portions
of the Great Lakes region. A shortwave/vorticity center lifting 
out over the mean ridge in the Great Lakes region will drive 
stronger confluence of the low level jet across Iowa to trigger another
round of strong to severe thunderstorms Tuesday evening. Overall 
deep layer steering flow and fairly orthogonal ascent over boundary
should help to focus a similar west to east (WNW to ENE) oriented 
axis of training thunderstorms. Upper-level dual jet couplet will 
further enhance up-scale growth to a broader complex to maintain 
through the overnight period. Most of the area remains at near or 
above record spring rainfall and soils are fairly saturated, so 
with cells capable of 1.5-2"/hr rates and localized totals of 2-3+"
suggest the placement of a Slight Risk of Excessive Rainfall 
across portions of eastern WI and central MI (along and north of 
I-94).

...Pecos River Valley through Southern Plains into Ozark Plateau...

A steady stream of PW values of 1.25 to 1.5 inches will be
advecting northward through the Southern/Central Plains nearly
parallel to the dryline. This will be conducive for slow storm
motion with locally heavy rainfall. Consensus suggests 3 to 4
inches possible within the isolated cells. The Marginal Risk area 
is connected to the area of concern over the Great Lakes and just 
note the coverage will decrease northward along the dry-line.

Campbell/Gallina


Day 2
Valid 12Z Wed Apr 15 2026 - 12Z Thu Apr 16 2026

...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM TEXAS TO
THE UPPER MIDWEST/GREAT LAKES REGION...

The surface to mid-level environment remains very similar to the 
prior 3 days, with a stark dry line extending from the Pecos River 
Valley across the Southern Plains into the Upper Mississippi 
Valley. During this period the longwave trough will finally be
making progress toward the Central Plains albeit as it begins to 
weaken and the deep layer moisture axis and instability shift 
slightly eastward. Thunderstorms are expected to break out with
hourly rates pulsing up to 2 inches/hr. Some locations ahead or
along the frontal boundary may receive over 3 inches between the
Ozarks Plateau and northeast Texas.

Further north, the environment over the Midwest/Great Lakes region
will have notably less moisture and instability present then the 
days prior, however additional rains will maintain an elevated 
threat for localized flooding over the hydrologically 
sensitive/saturated areas of the northern Great Lakes region. The 
most favorable location for appreciable precipitation will be from
northeast Illinois to souther Michigan. The Marginal Risk area was
maintained and in spans from northeast Texas northward to 
Wisconsin/Lower Michigan and east to western New Yorks and 
Pennsylvania.

Campbell/Gallina

Day 3
Valid 12Z Thu Apr 16 2026 - 12Z Fri Apr 17 2026

The probability of rainfall exceeding flash flooding guidance is
less than 5 percent.

Campbell

Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt
Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt
Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt