…Flooding and severe weather will be possible for the northern Plains
and Upper Midwest over the next couple of days …
… Early season heat wave to bring scorching temperatures to portions of
central Texas and the Rio Grande Valley…
…Cooler conditions out West will prevail behind the cold front and high
elevation snow will be possible …
Active weather is forecast across the northern Plains Wednesday and across
the Upper Midwest and Great Lakes on Thursday. On the threat for flooding,
A Slight Risk for Excessive Rainfall has been issued for areas in South
and North Dakota as there is the potential for locally heavy thunderstorms
to drop a quick 2-3 inches of rainfall. Some isolated flooding may also be
possible over the northern Plains on Thursday since the forming low
pressure will be slow to exit the region. For the severe weather threat,
Storm Prediction Center has a Slight Risk over the northern Plains as
surface instability, a moderate jet, and rather favorable lapse rates
bring the potential for strong winds and large hail. An isolated tornado
cannot be ruled out as well. The severe weather threat will shift eastward
on Thursday across the northern Ohio Valley, the upper Midwest, and the
Great Lakes region. The Storm Prediction has another Slight Risk (level
2/5). Both storm modes of supercells and an organized line of storms are
possible, with hail and strong winds being the main hazards again.
The south-central U.S. will be the epicenter for record warmth, especially
for much of Texas. Strong mid-level ridging and warm, southerly flow ahead
of a trough across the West will set the stage for a warm week. Multiple
stations are forecast to break record daily high temperatures records. An
Extreme Heat Warning is active over the Rio Grande and parts of Hill
Country, including metros of Austin and San Antonio, through tomorrow. A
Heat Advisory is active outside these zones. These watches and warnings
are likely to extended into later week as the pattern remains favorable
for dangerous heat. High temperatures in the upper 90s across the Texas
Gulf Coast to low 110s across the Rio Grande will bring high heat stress
potential. Take cool breaks, stay hydrated, and take care of vulnerable
populations such as the elderly and young.
The West is likely to see temperatures 10-15 degrees below average as a
strong upper-level trough dominates. Showery conditions are expected to
prevail across the central and northern regions of the West through this
work week. Late season snow will accompany the cooler conditions as well.
Mountains in the northern Rockies around Wyoming, Idaho, and Montana could
see higher than six inches of snow in the highest terrain from tonight
through tomorrow. Winter Storm Warnings and Winter Weather Advisories are
active. The Southwest will much warmer and drier as highs reach the 90s
and 80s. A Critical fire weather risk is active tomorrow for this region
as well with warm temperatures, gusty winds, and low relative humidities
providing favorable conditions.
The other notable weather risk will be a pulse storm severe weather threat
and residual flash flooding threat across the Southeast and Mid-Atlantic
tomorrow. The main shield of rain providing the heavier rain and higher
flood threat this afternoon should exit out by the over-night. The
upper-low should begin to weaken tomorrow, but there will be enough
moisture and instability to still provide the potential for a heavy
thunderstorm or two over saturated soils from previous days rainfall.
Therefore, WPC has a Marginal Risk for Excessive Rainfall across the
Southeast and Mid-Atlantic for Wednesday.
Wilder
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php
