…Record heat continues into the end of the week across the Southern
Plains…
…Record cold develops across California Friday into Saturday…
…Active monsoonal showers for the Southwest into the Southern Rockies…
…Showery weather on tap for Florida into the coastal Southeast and
across northern New England…
The mid to upper level flow is expected to remain highly amplified across
the Lower 48 over the next two days, comprised of a deep upper low moving
slowly across New England into the Canadian Maritimes, another strong
closed low dropping south along the Pacific Northwest coast and the
seemingly ever present closed upper high across the Southern Plains. This
mid to upper level pattern will be setting the stage for some big
temperatures contrasts across the CONUS over the next few days.
The persistent closed upper high over the Southern Plains will keep the
dangerous heatwave going across the Southern Plains as the week ends the
weekend begins. The recent batch of record high temperatures over the
Southern Plains will continue over the next two days with numerous record
highs possible from southeast New Mexico into large portions of Texas.
High temperatures across this region will be in the 100 to 110 degree
range producing widespread areas that will experience major to extreme
heat risks over the next two days. Excessive Heat warnings and heat
advisories are currently in effect across large portions of the Southern
Plains, affecting nearly 25 million people.
In contrast to the heat, both the eastern U.S. and western U.S. will see
below average temperatures over the next two days. For the east, an area
of high pressure will stretch from the Mississippi Valley to much of the
eastern seaboard, except for the coastal Southeast and Florida and
northern New England. This will produce below average temperatures and
dry conditions, although temperatures will begin to moderate back toward
seasonal norms by this weekend. The exceptions to the dry weather across
the eastern half of the nation will be across Florida into the coastal
Southeast and over northern New England. A stationary front is expected
to lie across north central Florida through the end of this week and into
this weekend, supporting showery conditions for Florida into the coastal
Southeast. Showery conditions also likely across northern New England
near the aforementioned strong closed upper low moving slowly eastward
across this region over the next two days.
While the below average temperatures will be waning across the east over
the next few days, the magnitude of below average temperatures will be
increasing across much of the west to the west of the Rockies. This is in
association with the above mentioned strong closed low moving southward
along the Pacific Northwest coast. This closed low will help push a
strong cold front inland from the eastern Pacific into the Pacific
Northwest on Thursday-Friday and southward into California and the Great
Basin Friday and Saturday. Much below average temperatures likely across
these areas Thursday, Friday and continuing into this weekend. There is
the potential for record cold afternoon high temperatures across large
portions of California on Friday, continuing into Saturday.
Between the Pacific Northwest closed upper low and the closed upper high
over the Southern Plains, above average monsoonal moisture values will be
transported northeastward between these two circulations, bringing the
potential for widespread scattered monsoonal shower and thunderstorms for
portions of the Southwest, Great Basin and Southern Rockies. Locally heavy
rains across these areas will also pose the risk of flash floods,
especially in areas of steep terrain and in slot canyon regions.
Oravec
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php
