SPC AC 060059
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Thu Jun 05 2025
Valid 060100Z - 061200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL AND SOUTHERN PLAINS...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...
...SUMMARY...
Scattered severe thunderstorms will continue across the southern and
central Plains tonight. Several tornadoes (some possibly strong),
large to very large hail, and severe gusts are possible. Isolated
severe gusts are also possible the next few hours over parts of the
Northeast.
...01z Update...
Early-evening satellite imagery suggests a weak short-wave trough is
cresting an elongated southern-U.S. ridge over the High Plains. This
feature is currently located over eastern CO/northeast NM and will
approach the MO Ozark region by the end of the period. Partly in
response to this feature, LLJ should increase ahead of the short
wave over the next few hours across western OK into extreme southern
KS. As a result, a corridor of increasing low-level warm advection
is expected to focus along the KS/OK border and this should
encourage significant convective development by mid evening. 00z
sounding from AMA exhibited around 3000 J/kg SBCAPE with around 50kt
0-6km shear and minimal CINH. This air mass will be drawn into the
aforementioned warm-advection corridor and readily convect as the
LLJ increases.
Farther southwest, a cluster of supercells persists across the TX
South Plains along the periphery of early-day rain-cooled boundary
layer. LLJ is expected to aid this activity as it propagates
east-southeast across northwest TX.
Very large hail, along with a continued risk for tornadoes persists
with this activity. If supercell mergers evolve into an MCS then
damaging winds may become more common later this evening.
...Northeast...
A small cluster of strong/severe thunderstorms continues across
northeast PA into southern NY ahead of a weak short-wave trough.
Latest radar data suggests a weak MCV may be evident over Tioga
County PA, and this may encourage convection immediately downstream
into Delaware County NY over the next few hours.
..Darrow.. 06/06/2025
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 051728
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1228 PM CDT Thu Jun 05 2025
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN
HIGH PLAINS TO THE TN/LOWER OH VALLEYS...AND ACROSS PORTIONS OF
SOUTHERN NEW ENGLAND...
...SUMMARY...
Scattered severe thunderstorms are expected from the southern High
Plains to the Tennessee and Lower Ohio Valleys on Friday into Friday
night. Damaging winds and a couple tornadoes are the main hazards.
Large to very large hail is possible over the southern High Plains.
Additional severe storms producing damaging wind gusts are possible
across portions of southern New England Friday afternoon.
...Central/Southern High Plains into OK...
An MCS will likely be ongoing Friday morning across portions of the
Ozarks and arcing into parts of OK. The southern end of this
convection over the southern Plains will likely weaken during the
morning with an outflow reinforced boundary becoming oriented across
southern OK into the southern TX Panhandle/South Plains and
east-central NM. It is uncertain how far northward this boundary may
modify northward through the afternoon. Southerly low-level flow
will maintain a very moist airmass (mid 60s to low 70s F dewpoints)
near and south of the boundary, with more modest dewpoints (50s to
low 60s F) further north from eastern CO/northeast NM into southern
KS/northern OK.
Moderate westerly flow aloft will persist through the day, with
neutral height tendencies until late (after 06z) in the period when
some modest height falls are forecast as a shortwave impulse moves
east/southeast across the central Rockies into the central Plains.
This will aid in the development of a 30-40 kt southwesterly jet
across the southern High Plains during the overnight hours.
The expectation is that isolated to widely scattered supercells will
develop over the higher terrain of southeast CO/eastern NM/far west
TX in a moist upslope flow regime as strong heating occurs through
the afternoon. Stronger MLCAPE (up to 3000 J/kg) will be confined to
the area near the surface outflow where stronger low-level moisture
will be focused. Elongated/straight hodographs above 2 km and steep
midlevel lapse rates suggest large to very large hail will be
possible (greater than 2 inch diameter) in addition to strong gusts.
There is some potential convection could organize into a southeast
propagating cluster/MCS moving from southeast CO/northeast NM into
the northwest OK overnight. Higher outlook probabilities could
become necessary if confidence in this scenario increases and as
mesoscale details (location of surface outflows) become better
resolved.
...Ozarks to TN/Lower OH Valleys...
An MCV tied to ongoing morning MCS over the Ozarks will develop
eastward into the OH Valley through evening. Morning convection may
weaken initially before re-invigoration/redevelopment occurs during
the afternoon as the downstream airmass becomes moderately to
strongly unstable, aided by strong heating and dewpoints in the
upper 60s/low 70s F. Damaging gusts will be the main hazard with
this activity, especially if updraft consolidation occurs within
storm clusters closer to the MCV where midlevel flow will be
enhanced, resulting in some forward propagation. Vertical shear will
be more modest with southward extent, but instability will be
stronger, supporting at least an isolated severe wind risk into the
TN Valley vicinity.
...Portions of southern New England...
A weak surface boundary will be draped across portions of New
England into central OH Friday afternoon. Ahead of this boundary,
rich low-level moisture (mid 60s to low 70s F) dewpoints will be
focused in a corridor from eastern PA into MA/CT and southern
VT/NH/ME. Strong heating within this corridor will result in a
narrow corridor of moderate destabilization (MLCAPE greater than
2000 J/kg). Steepened low-level lapse rates also will foster DCAPE
near 1000 J/kg. Vertical shear will remain modest, around 20-25 kt
effective shear magnitudes, but strong instability will support
strong to severe storms capable of damaging gusts through the
afternoon.
..Leitman.. 06/05/2025
WUUS02 PTSDY2
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
SPC AC 051911
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0211 PM CDT Thu Jun 05 2025
Valid 071200Z - 081200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE SOUTHERN PLAINS INTO THE SOUTHEAST...
...SUMMARY...
Scattered severe thunderstorms are expected from the southern Great
Plains to the Southeast States on Saturday through Saturday evening.
Damaging winds should be the primary hazard.
...Southern Plains to the Southeast...
A series of upper shortwave troughs will be located over the central
Plains and the central/southern Appalachians Saturday morning,
providing a belt of enhanced mid/upper westerly flow across the
region. An MCS is likely to be ongoing across OK at the beginning of
the period. This activity may weaken through the morning as it
shifts east into AR through midday. Downstream across the Mid-South,
a corridor of moderate to strong instability is forecast amid rich
boundary-layer moisture. Convection will likely redevelop/intensify
by early afternoon and shift east across parts the TN Valley to SC
through the evening hours. Additional convection may develop across
eastern NC during the afternoon within a moderately unstable airmass
and within enhanced mid/upper flow associated with the eastern upper
shortwave trough. Swaths of scattered damaging gusts will be the
main hazard with this activity.
More isolated convection may develop along residual outflow and
within a corridor of strong heating and low-level upslope flow
across the southern High Plains late Saturday afternoon. A deeply
mixed boundary layer and supercell wind profiles amid steep midlevel
lapse rates could support isolated severe wind/hail despite weak
forcing for ascent.
...Eastern Dakotas into northwest MN...
A deepening upper shortwave trough over the Canadian Prairies will
develop southeast across the northern Plains on Saturday.
Boundary-layer moisture will remain modest, with surface dewpoints
generally remaining in the upper 40s to mid 50s F ahead of a
southeastward-advancing cold front. Nevertheless, cooling aloft and
surface heating into the 80s will support weak instability and
steepened low-level lapse rates. Vertically veering wind profiles,
with 30-40 kt flow from 850-500 mb will support organized cells.
Isolated strong gusts could occur with this activity during the
afternoon and early evening.
..Leitman.. 06/05/2025
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
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