National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS01 KWBC 182018
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 PM EDT Thu Apr 18 2024

Valid 00Z Fri Apr 19 2024 - 00Z Sun Apr 21 2024

...Severe weather and isolated flash flooding mostly likely over
the Midwest into the Ohio Valley in early Friday with
thunderstorms extending southwest into Texas...

...Wet snow and wintry mix over the central High Plains on
Saturday as heavy rain threat develops and expands over Texas...

...Unseasonably warm across much of the South and Southwest as
cold air from Canada pours south into the Great Plains...

A relatively progressive weather pattern is forecast to establish
across the nation as we head into the weekend.  This progressive
pattern will kick a relatively slow-moving low pressure system
further out into the Atlantic while allowing a cold air mass from
Canada to pour southward into the Great Plains.  A low pressure
wave currently developing along the boundary of the cold air mass
over the Midwest will bring an enhanced threat of severe
thunderstorms across the Midwest tonight, moving into the Ohio
Valley early on Friday.  A slight chance of severe thunderstorms
is forecast to extend farther southwest into central Texas near
the trailing portion of the cold front.  In addition to the severe
weather threat, the heavy rain associated with the thunderstorms
may result in flash flooding concerns at some places for
aforementioned areas.

By Friday, the cold front is forecast to move steadily east toward
the East Coast.  Showers and thunderstorms will likewise move
farther east out of the Ohio Valley and into the Appalachians,
reaching into the interior Mid-Atlantic, Southeast, and New
England by Friday evening.  The severe weather threat is expected
to be not as high on Friday for these areas.  Saturday will see
these showers and storms steadily exiting the East Coast as the
cold front pushes off the coast into the Atlantic.  However,
interior New England will see the showers linger due to the
arrival of a reinforcing cold front from Canada.

As a large dome of high pressure system associated with the
Canadian cold air mass settles into the Great Plains, the upslope
dynamics will set up the opportunity for wet snow to develop over
the central High Plains on Saturday, mixing with rain during the
day.  Meanwhile, as an upper trough moves farther east into
northern Mexico on Saturday, the associated dynamics will support
an expanding area of rain over the southern Plains as the trough
interacts with moist air returning from the Gulf of Mexico.  It
appears that the threat of heavy rain threat will expand through
eastern Texas by the end of the forecast period on Saturday
evening.

Much of the western U.S. will remain dry through the next couple
of days but the next Pacific system will likely break the drought
later on Saturday as rain reaches the Pacific Northwest.  Forecast
high temperatures will remain rather warm across southern and
southwestern portions of the country through Saturday but the cold
front will dispel some of the warmth across the Mid-South,
Midwest, Great Lakes, and eventually the Northeast with the
passage of the cold front.  In contrast, cold air will gradually
push southward through the Great Plains reaching into central
Texas by Friday.

Kong


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

$$