The Nation’s Weather

…A low pressure system will bring a round of moderate to heavy rain and
gusty winds from the Ohio Valley to the Mid-Atlantic states today then
across New England on Saturday…

…Severe thunderstorms possible later today for the Mid-Atlantic and the
Southeast…

…Heat risk expected to reach major level for interior California and
portions of the Southwest Friday and Saturday…

A low pressure system currently developing over the Midwest is forecast to
track across the northern Mid-Atlantic by tonight and intensify to a
rather strong system for late May as it reaches New England on Saturday.
A round of moderate to heavy rain along with increasingly gusty wind can
be expacted along the track of this low pressure system. The highest
chance of heavy rain will be across the Ohio Valley today and then into
the northern Mid-Atlantic by tonight. Some thunderstorms embedded within
the rain can be strong to severe, possibly resulting in local areas of
flash flooding. The low is forecast to deepen further as the center
tracks northeastward through New England on Saturday with a swath of
moderate to heavy rain across the interior sections, along with gusty wind
expanding across the Northeast. From the Mid-Atlantic southward into the
Southeast, lines of thunderstorms could contain severe weather as a cold
front associated with the intensifying system sweeps across the region
later today into tonight. The cold front will move off the East Coast
later tonight but the instability associated with a cold upper-level
trough could trigger scattered thunderstorms across the Mid-Atlantic
region even though temperatures will be cooler behind the cold front on
Saturday. By Saturday night into Sunday morning, a reinforcing cold front
will bring temperatures further down into the 40s and 50s from all of the
Great Lakes through the Northeast and down into the Mid-Atlantic.

Meanwhile, scattered thunderstorms associated with the trailing cold front
are expected across the Deep South today before pushing off the Gulf Coast
by tonight. In contrast to the rain and cooling trend in the eastern
U.S., a strong ridge of high pressure will bring heat and persistent dry
weather across the western U.S. and into the northern Plains. In fact,
record high temperatures will be threatened across interior northern
California today, expanding into the Great Basin, Idaho, and as far north
as western Montana on Saturday. The anticipated heat in the Southwest for
the next couple of days has led to the issuance of Extreme Heat Warnings
for the dangerous heat for portions of southernmost Nevada, southeast
California, and northwestern most Arizona. Drinking plenty of water,
wearing light colored clothing, and staying in air conditioned areas is
advised as temperatures soar as high as the mid 110s Fahrenheit in lower
desert locations like Death Valley, California. A cold front from the
Pacific is forecast to bring marked cooling into the Pacific Northwest
later on Saturday into Sunday but with minimal rainfall expected through
early on Sunday with the commencement of June.

Kong

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