Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
341 PM EDT Wed Jul 17 2019
Valid 00Z Thu Jul 18 2019 - 00Z Sat Jul 20 2019
...Post-Tropical Cyclone Barry remains a flooding threat for portions of
the northern Mid-Atlantic and Southern New England...
...Flash flooding and severe weather are both possible from the Northern
Plains to the Upper Midwest/Great Lakes through Thursday...
...A dangerous heat wave continues to grip much of the country from the
Plains to the East...
Post-Tropical Cyclone Barry continues to weaken this afternoon with the
center of circulation expected to become less and less distinct through
tonight. Tropical moisture associated with Barry will interact with a
frontal boundary to its north resulting in heavy rainfall and scattered
thunderstorms across the northern Mid-Atlantic to southern New England.
Rainfall amounts of 1 to 2 inches, with locally higher amounts, are
forecast and WPC has a slight risk for excessive rainfall/flash flooding
in place through early Thursday morning. SPC also indicates a slight
chance for severe weather across parts of the same region tonight.
Lingering tropical moisture farther south may also result in pockets of
heavy rainfall across the Tennessee Valley and Southern/Central
A series of slow moving frontal boundaries across the north-central U.S.
will bring showers and thunderstorms from the Upper Great Lakes to the
Northern and Central Plains the next few days. The best chance for heavy
rainfall and strong to severe storms this evening and tonight will be
across the Upper Midwest and portions of the Northern Plains, with the
threat shifting slightly eastward into the Upper Great Lakes on Thursday
and into Friday.
The biggest story in the short range though is a strengthening upper level
ridge across the Central and Eastern U.S. resulting in oppressive and
dangerous heat across the eastern two thirds of the country. Widespread
excessive heat warnings, watches, and heat advisories are in effect across
much of the Central U.S., into the Ohio Valley, and along parts of the
Eastern Seaboard. Daytime highs in the 90s to near or above 100 are
expected, and combined with dewpoints soaring into the mid to upper 70s,
will result in heat indices (feels like temps) as high as 110 in some
places. Temperatures overnight will struggle to recover much with near or
surpassing record values in the mid to upper 70s or near 80 for many. The
dangerous heat will also continue or worsen over the weekend beyond the
short range period.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php