…Active severe weather setup from the southern Plains to the
Mid-Atlantic through Tuesday…
…Heavy showers & thunderstorms to pose both a flash flooding and severe
weather threat for the eastern Great Lakes, Mid-Atlantic, and Northeast…
…Stifling heat dome to build in throughout much of the West and the
western Gulf Coast; hottest temperatures compared to normal centered over
the Northwest…
A pair of frontal boundaries will act as catalysts for widespread showers
and thunderstorms this afternoon and into the start of the upcoming week
across much of southern and eastern U.S.. The Southern Plains are most
at-risk for severe weather this afternoon and into tonight, highlighted by
the Storm Prediction Center (SPC) placing northern Texas and southern
Oklahoma under a Moderate Risk (threat level 4/5) which includes the
greater Dallas/Fort Worth metro area. The primary concern is a long-track
line of intense thunderstorms with destructive wind gust potential tonight
that could track a long enough distance and produce enough damage to be
considered a “derecho”. There is also the concern for tornadoes and large
hail this afternoon and into tonight in this region as well. The severe
weather potential also extends farther away from the Red River region with
severe storms stretching from the TX/OK Panhandles on east to the Lower
and Middle Mississippi River Valleys. Farther east, a compact storm system
tracking through the Upper Ohio Valley this afternoon will support a
severe weather threat from the Ohio River on east to the Mid-Atlantic and
Southeast coasts. SPC has a lengthy Slight Risk (threat level 2/5) that
goes from southern Georgia on north to the DC/Baltimore metro areas. In
addition to the severe weather potential today and tonight, WPC has
several Slight Risk areas (threat level 2/4) for threat of flash flooding
in the Red River Valley and ArkLaTex, along the Central Gulf Coast, and
from the Upper Ohio Valley on east to the Virginia Tidewater.
The severe and flash flooding potential continues tomorrow throughout the
South and up the East Coast as the southern frontal boundary inches closer
to the Gulf Coast and a new encroaching cold front approaches the East
Coast from the Great Lakes. Slight Risks for Excessive Rainfall are in
place in the Deep South and the northern Mid-Atlantic, while the severe
threat stems from eastern New Mexico and across the South to areas as far
north as the eastern Great Lakes. Tuesday should remain active from the
Rio Grande Valley on east along the Gulf and East Coasts. SPC features an
expansive Marginal Risk (threat level 1/5) in these areas, while WPC has a
Slight Risk posted fro southeast New Mexico and western Texas. Farther
south, Florida’s rainfall/thunderstorm chances look to increase through
the first half of the week as the cold front inches closer to the
Panhandle each day.
While the South and East are mired in a stormy weather pattern, the West
will be mostly dry to close the weekend and to open the upcoming week. The
lone exceptions are the mountains ranges throughout the West which include
the Sierra Nevada, the Great Basin, and along the spine of the Rockies.
Look for diurnally-driven showers and thunderstorms each afternoon and
evening that dissipate each night across the Intermountain West. The
Desert Southwest and Pacific Northwest will not only be dry, but grow
hotter each day into the first half of the week. The hottest temperatures
compared to normal for early-mid June are most likely to be found in the
Northwest with daily high temperatures encroaching upon daily record highs
through Tuesday. High temperatures will soar into the 90s across the
interior Northwest with some spots forecast to hit the century mark. NWS
HeatRisk shows widespread Moderate Impacts and scattered areas of Major
Impacts across the Portland metro area today and the Columbia Basin on
Monday. Similar HeatRisk criteria exists from the Great Valley of
California on south through the remainder of the Desert Southwest. High
temperatures are forecast to easily reach the 90s and even the 100s
(particularly the Mojave Desert and Lower Colorado River Basin) each day.
Farther east, searing heat remains a common occurrence from the Big Bend
of Texas on east through much of south Texas and in far southern
Louisiana. HeatRisk shows Major heat impacts (heat that effects anyone
without effective cooling/hydration) in metro areas that include San
Antonia and Houston through Monday.
Mullinax
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php
