Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Mon Mar 10 2025
Valid 131200Z - 181200Z
...DISCUSSION...
...Day 4/Thu - Southeast...
A shortwave upper trough will move across the Southeast on Thursday.
Stronger deep-layer flow will mainly be focused over the Gulf.
However, cooler temperatures aloft will support weak instability and
a strong storm or two may occur over portions of AL/GA and the FL
Panhandle. Overall severe potential appears limited.
...Day 5/Fri - ArkLaTex to the Mid/Lower MS Valley vicinity...
A regional outbreak of severe storms is forecast late Friday
afternoon into the overnight hours. An intense upper cyclone will
deepen as it ejects northeast from the central/southern Plains to
the Upper Midwest by Saturday morning. A 100+ kt 500 mb jet streak
will move across OK into the Ozark Plateau during the late afternoon
and evening, before lifting north across the Mid-MS Valley
overnight. At the surface, a rapidly deepening surface low will move
across the central Plains to the Upper Midwest, with a cold front
surging east across the region from late afternoon into Saturday
morning.
Deeper Gulf moisture will be confined to the I-20 corridor Friday
morning. However, intense low-level flow will quickly transport
moisture northward through the mid-MS Valley. Surface dewpoints
greater than 60 F will likely remain south of the MO Bootheel
vicinity, with a broader area of more modest moisture as far north
as northeast IA/southwest WI and northern IL. While moisture will be
less favorable with northward extent, strong large-scale ascent,
intense deep-layer flow and a surging cold front will likely be
sufficient for severe convection even amid weak instability. Further
south from the ArkLaTex vicinity to the Lower MS Valley, better
quality moisture is expected to overlap intense shear. Overall, this
pattern will support all severe hazards, with a potential mixed mode
evolution (QLCS and supercells).
The north and east extent of severe potential remains a bit
uncertain either due to moisture concerns and/or spread among
various guidance in timing and position of key features. Severe
probabilities will likely be refined over the coming days as these
features become better resolved.
...Day 6/Sat - Southeast...
The Upper Midwest cyclone will eject northeast into Ontario on
Saturday. Meanwhile the base of the larger-scale upper trough over
the Plains ejects east toward the Lower MS Valley and Southeast.
This will maintain strong deep-layer southwesterly flow across the
region, with an intense low-level jet expected to develop by late
afternoon as stronger height falls overspread the Deep South.
Ongoing convection at the beginning of the period from the Lower OH
Valley toward northern MS/LA adds some uncertainty regarding how the
airmass will destabilize (especially with northward extent).
However, it appears likely that a very favorable corridor of rich
boundary layer moisture will overlap strong shear from
central/southern MS into northern AL ahead of a cold front expected
to surge across the area during the evening. This overall pattern
appears favorable for both supercells and an eventual QLCS.
...Day 7/Sun - Eastern states...
The upper trough over the central U.S. will lift northeast over the
eastern states on Sunday. Some severe potential is possible given
strong deep-layer flow atop a moist boundary layer ahead of the
eastward-advancing cold front. However, destabilization may be
limited by widespread training precipitation.
..Leitman.. 03/10/2025
