018
FXUS02 KWBC 082000
PMDEPD

Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
400 PM EDT Mon Jun 8 2026

Valid 12Z Thu Jun 11 2026 - 12Z Mon Jun 15 2026


...Significant heat wave culminates late week from the Mid-Atlantic
to the Northeast with hot conditions extending into the south-
central U.S. through Sunday...

...Severe weather and heavy rain threats across the Upper Great
Lakes/Ohio Valley/Mid-Mississippi Valley...


...Overview...

Continued eastward ejection of an upper trough will push a front
across the northern tier of the U.S., bringing an end to the early
season heatwave with a round of severe thunderstorms and heavy
rain across the Midwest Thursday-Friday. Meanwhile, the heat is
forecast to reach its peak from the Mid-Atlantic to the Northeast
before gradual moderation this weekend. Showers and thunderstorms
appear more numerous across the south-central U.S. by Friday and
through early next week as the trailing end of the front is
forecast to stall across the central U.S. Over the Pacific
Northwest, heat is forecast to develop by Sunday as an upper ridge
is forecast to strengthen.


...Guidance/Predictability Assessment...

The gradual trend toward a faster ejection of the upper trough
across the northern tier states appears to have halted with this
morning`s model consensus. Meanwhile, the heat will likely reach
its peak Thursday to Friday from the Mid-Atlantic to the Northeast
with prominent lee troughing over interior Mid-Atlantic. Guidance
generally agrees that upper troughing/lower heights will edge into
the Northeast leading to gradual moderation of the heat but the
lead cold front will meet resistance while trying to erode the
upper ridge. Meanwhile, guidance generally agrees that troughing
will dip into the northern tier that favors cold air intrusion from
Canada by this weekend into early next week.

Meanwhile, guidance appears to support a shortwave to dip south
along the spine of the Rockies this weekend into early next week
toward the trailing end of the front over the southern High Plains
with rounds of showers and storms spanning multiple days across the
south-central U.S. Latest guidance (particularly the EC cluster)
supports higher QPFs farther south than previous forecasts. This is
reflected in the latest WPC forecasts.

The WPC forecast for fronts/pressures was based on a multi-model
blend of the 00Z and 06Z guidance early in the forecast, with
increasing proportions from the GEFS/EC/CMC ensemble means as the
period progressed toward Day 7 amid increasing spread.


...Weather/Hazards Highlights...

A cold front is forecast to push across the Midwest on Thursday
and provide a focus for thunderstorms in a moist and unstable
environment. Flash flooding is a possibility with potentially
repeating rounds of convection, and a Slight Risk is in place
across portions of the Midwest in the Day 4/Thursday ERO. The
Storm Prediction Center is calling for a risk of severe weather in
a similar area as well. The front will push eastward into Friday
and could produce locally heavy rain in parts of the Appalachians
Friday, and a Marginal Risk is indicated there for the Day 5/Friday
ERO. Meanwhile, the front will start to extend from west to east
across the central U.S. and meander near south-central parts of the
Plains and Mississippi Valley to the Tennessee/Ohio Valleys,
allowing for the Marginal to stretch across those regions. The
generally west to east oriented front is forecast to meander in the
central U.S. for multiple days. Thus thunderstorms will be common
in that region into the weekend, with heavy rain potential and
additional flood risks especially if rounds of rain repeat over
similar areas. Scattered thunderstorms that tend to be diurnally
driven are likely in the Southeast (including Florida) and
potentially expanding into the Mid-Atlantic for multiple days.
Elsewhere, the northern Rockies and High Plains may see some
precipitation, dependent on the evolution of shortwave energy.

The mean upper-level ridge over the eastern U.S. is expected to
bring the first significant heat of the summer into late week, as
temperatures reach 10-15 degrees above average. The heat looks to
reach its peak across the Mid-Atlantic and Northeast on Friday, and
several record highs and record warm minimum temperatures could be
set, before gradually moderating by the weekend. See WPC`s Key
Messages for more. Subtropical ridging across the southern tier
will yield hot conditions there as well, generally a few degrees
above already warm averages. The Desert Southwest can expect
temperatures well into the 100s, while heat indices should be over
100 in the southern Plains to Lower Mississippi Valley. Into early
next week, upper ridging possibly reaching the West Coast could
bring well above average temperatures particularly to the Pacific
Northwest.


Kong/Tate


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, excessive rainfall outlook,
winter weather outlook probabilities, heat indices and Key Messages
are at:

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





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