267 
FXUS01 KWBC 201908
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
307 PM EDT Sat Jun 20 2026

Valid 00Z Sun Jun 21 2026 - 00Z Tue Jun 23 2026

...Impactful flash floods and severe storms expected over the
Plains and Midwest today and tomorrow; locally significant flash
flooding also remains possible today across the Southeast and Gulf
Coast...

...Widespread thunderstorms with a flash flood threat expected
across the Northeast, Ohio/Tennessee/Lower Mississippi Valleys,
and into the southern Plains Monday...

...Conditions remain uncomfortably hot across the Southeast with
stifling humidity in place while a pair of cold fronts brings mild
conditions in the 70s to the northern tier of the central/eastern
U.S.... 

An expansive storm system will bring widespread storms with a
threat for flash flooding and severe weather to much of the
central to eastern U.S. through the weekend and into early next
week. An upper-wave has led to a deepening surface low in the lee
of the Rockies today (Saturday). Increasing southerly flow with an
upper-ridge just to the east has primed a very moist, unstable
airmass expected to lead to widespread storm development across
the central Plains this afternoon. The Storm Prediction Center
maintains a Slight Risk of severe weather (level 2/5) for the
threat of large hail, damaging winds, and a few tornadoes. As the
evening progresses, robust thunderstorms are expected to
grow-upscale ahead of increased forcing from an incoming cold
front, forming a line of storms progressing eastward through the
overnight hours. There is a more focused Enhanced Risk (level 3/5)
where these more concentrated, intense storms will bring the risk
of very large hail and more widespread, significant damaging winds
from northeastern Colorado into southern Nebraska and northern
Kansas. In addition, plentiful moisture will favor very heavy
downpours, and the expanding coverage of storms with the organized
system as it progresses east will bring long duration heavy
rainfall. A Moderate Risk (level 3/4) of Excessive Rainfall
extends from southeastern Nebraska/northeastern Kansas into
northwestern Missouri where scattered to widespread flash flooding
is expected. A broader Slight Risk is in place across the central
Plains into the Middle/Lower Missouri Valley for more scattered
instances of flash flooding.

These storms are forecast to continue into the day Sunday into the
Middle Mississippi and Lower Ohio Valleys. Another round of storms
is expected ahead of the approaching cold front back through the
Missouri Valley and adjacent central Plains as the atmosphere
destabilizes following the overnight storms. Scattered to
widespread flash flooding will remain a threat with another
Moderate Risk of Excessive Rainfall in place. Some storms may also
be severe, and the SPC has a Slight Risk ahead of the front
covering these same regions as well as westward towards the
central High Plains as post-frontal upslope flow sets up. Large
hail, damaging winds, and a few tornadoes will all remain threats.
The low pressure system will continue eastward through the Ohio
Valley into the Northeast on Monday with the trailing cold front
extending southwestward through the Ohio/Tennessee/Lower
Mississippi Valleys and into the southern Plains. This will lead
to another round of scattered to widespread storms along the
length of the front. An expansive Slight Risk of Excessive
Rainfall extends along this front to cover the threat for more
heavy downpours and scattered instances of flash flooding.

Deep Gulf moisture ahead of a lingering frontal boundary north of
the Gulf Coast will continue to lead to scattered to widespread
heavy rain-producing thunderstorms through this evening with a
threat for scattered, locally significant flash flooding as a
Slight Risk of Excessive Rainfall remains in place. Back to the
northwest, the energetic flow will bring another upper-wave
through the Great Basin/northern Rockies today and into the
northern Plains Sunday, bringing a chance for scattered
thunderstorms. A more concentrated focus of storms along a frontal
boundary across South Dakota Sunday will lead to some locally
heavier rainfall and scattered flash flooding, with a Slight Risk
of Excessive Rainfall in place. This frontal system will progress
slowly eastward through Monday with another round of thunderstorms
forecast for the northern Plains and into the Upper Midwest.
Elsewhere, a backdoor cold front sagging southwestward into New
England will bring some thunderstorms to the region Sunday. The
upper-wave passing through the Interior West will also lead to
some gustier winds across the region, with very low humidity and
mostly dry thunderstorm chances prompting a fire weather threat.
The SPC has outlooked a Critical Risk for fire weather (level 2/3)
over the eastern Great Basin/Four Corners with a more expansive
Elevated Risk (level 1/3) more broadly across much of the region.

Despite generally near-average highs in the upper 80s to mid-90s
across the Southeast to Southern Plains, conditions will remain
uncomfortably hot through the next couple days with stiffing
humidity present. Heat Advisories cover portions of the reason as
heat indices will rise well into the 100s for many. The southern
High Plains will also remain hot as temperatures soar into the
100s. Meanwhile, frontal passages this weekend will bring very
mild, below to well below average highs to the northern/central
Plains, Midwest, and Northeast through the next few days.  Highs
in the 70s will be common. A mostly near average to just above
average weekend continues across much of the western U.S. with
highs in the 80s. Conditions  will trend hotter into early next
week, with highs rising into the 90s. Coastal regions will remain
cooler and in the 60s and 70s while the Desert Southwest will see
highs in the 100s.


Putnam


Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php




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