Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
312 PM EDT Wed Apr 1 2026

Valid 12Z Sat Apr 04 2026 - 12Z Wed Apr 08 2026


...Heavy rain and flooding potential could persist in the south-
central U.S. to east-central U.S. on Saturday...

...Another round of April snow and ice possible across the
northern tier into the weekend...


...Overview...

A low pressure system will cross the Great Lakes and bring its
trailing cold front across the central and eastern U.S. over the
weekend. This will draw ample moisture and instability northward
from the Gulf and produce widespread rain and thunderstorms with
potential flooding concerns across parts of Texas, the Lower
Mississippi/Tennessee/Ohio Valleys, and into the Great Lakes on
Saturday. The front should push rain chances more progressively
through the East on Sunday. Ice and snow are forecast on the
northern side of the system across parts of the northern Plains,
Midwest, and northern New England. Cooler temperatures are likely
behind the front in the central and eastern U.S., but the West can
expect warming temperatures into early next week underneath upper
ridging.


...Guidance/Predictability Assessment...

Model guidance has stabilized on the track and timing of the
primary upper low moving through the Midwest to Great Lakes
accompanied by the surface low over the weekend, with only minor
spatial and temporal differences noted. Upper troughing then looks
to maintain itself over the eastern U.S. into early next week as
multiple shortwaves dive southeastward across the Midwest and
vicinity, though with some typical model spread on their timing and
strength. Ridging upstream across the western U.S. over the
weekend seems rather predictable and is forecast to gradually shift
east early next week.

Behind the ridge, models continue to show a fair amount of
variability with respect to a low digging southeastward out of the
Gulf of Alaska and a separate upper low approaching the coast of
northern California from the open Pacific by Tuesday-Wednesday. For
both features, but particularly the southern-most upper low, the
00Z and 06Z runs of the GFS were on the faster end of the guidance
envelope, while the 00Z ECMWF and CMC were slower. The latest 12Z
guidance reflects a similar positioning between the deterministic
models, with the EC-AIFS slower than the GFS, but faster than the
ECMWF and CMC. Interestingly enough, the EC and CMC ensemble means
were closer to the middle ground of the EC-AIFS, while the GEFS
mean was a touch faster.

Given the reasonable agreement among the model guidance initially,
the WPC forecast used a multi-model blend for the early part of
the forecast period. As the period progressed, increased weighting
of the ensemble means to 50 percent of the blend by Day 7, to limit
the influence of individual model differences especially across
the West.


...Weather/Hazards Highlights...

Low pressure tracking through the Midwest and Great Lakes will
bring active weather across the central to eastern U.S. over the
weekend. Well above average moisture and instability are likely to
pool along and ahead of the associated cold front and produce
widespread convection with favorable jet dynamics. A large Marginal
Risk remains in place for the Day 4/Saturday ERO, which stretches
from parts of Texas across the Mid-South, Ohio Valley, and Great
Lakes all along and ahead of the front. Areas farther south should
have more available instability and slower frontal movement for
more overall rain, but areas farther north will see better forcing
and lower Flash Flood Guidance, so a Marginal seems reasonable for
the whole area. The front should reach the Eastern Seaboard Sunday
and provide widespread precipitation chances there. Instability is
likely to be more limited though, and fast frontal movement may
preclude too many flooding concerns. Will keep the Day 5/Sunday ERO
at less than 5 percent for flash flooding, but there may be
nonzero chances if particularly sensitive areas receive high rain
rates. Rain should linger across Florida into Monday and Tuesday,
and perhaps along Gulf and Atlantic coastal areas, with more
uncertainty.

Snow and ice are also potential impacts with this low pressure
system. Some modest snow is possible on the backside of the low in
the Upper Midwest on Saturday. A swath of freezing rain and sleet
is also expected across portion of the Upper Great Lakes Saturday
and farther east into Maine Saturday night into early Sunday
morning. Snow and ice amounts remain uncertain so stay tuned for
future updates. Enhanced winds are possible in the Midwest and
vicinity due to the low. Some lake effect precipitation is possible
in the broad westerly flow behind the system. Then another round
of light precipitation, with possibly some snow, is forecast in the
north-central U.S. Sunday and Monday as multiple shortwaves pass
over behind the main system. Farther west, most areas will stay
generally dry other than some possible Four Corners convection by
early next week, and the Pacific Northwest should see increasing
precipitation chances by Tuesday depending on the evolution of an
approaching upper low.

Well above average temperatures are likely across the Ohio Valley
into the Mid-Atlantic and Northeast on Saturday, as highs reach the
70s to the Canadian border in the Lower Great Lakes region. A
handful of record highs could be approached or set. A cooling trend
is then likely to spread from the central U.S. Saturday across the
East on Sunday and Monday for more seasonable to slightly below
average temperatures. Meanwhile, the West can expect gradually
warming temperatures to 10 to 20 degrees above average by the
weekend and early next week as upper ridging comes in. Above normal
temperatures should spread into the Rockies and parts of the
Plains as the week progresses.


Tate/Miller


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation forecast (QPF), excessive rainfall
outlook (ERO), winter weather outlook (WWO) probabilities, heat
indices, and Key Messages can be accessed from:

https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/#page=ero
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml
https://www.wpc.ncep.noaa.gov/#page=ovw