No watches are valid as of Sat Mar 14 19:58:01 UTC 2026.MD 0237 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE SOUTHERN FLORIDA PENINSULA
Mesoscale Discussion 0237
NWS Storm Prediction Center Norman OK
0233 PM CDT Sat Mar 14 2026
Areas affected...portions of the southern Florida Peninsula
Concerning...Severe potential...Watch unlikely
Valid 141933Z - 142130Z
Probability of Watch Issuance...20 percent
SUMMARY...Scattered thunderstorms ongoing along typical sea breeze
fronts may briefly organize with the potential for sporadic hail and
some damaging gusts. A WW is unlikely.
DISCUSSION...As of 1925 UTC, regional radar and satellite data
showed scattered thunderstorms had developed and begun to mature
along typical sea breeze boundary corridors across the southern and
eastern FL peninsula. Strong surface heating amid upper 60s to low
70s F surface dewpoints was supporting 1500-2000 J/kg of MLCAPE.
While deep-layer flow is modest, easterly low-level flow and 180
degree opposed 20-25 kt winds aloft are supporting sufficient
deep-layer shear (25-30 kt) for organized multicells and some
transient supercell structures. Given the storm mode and favorable
thermodynamics, a few of the stronger cells appear capable of
sporadic hail. Additionally, high PWAT content could support a few
stronger downdrafts capable of damaging gusts.
Current trends and recent CAM guidance suggests convection should
increase in coverage through this afternoon across the eastern and
southern parts of the FL Peninsula. Storms may intermittently
strengthen and weaken with some risk for localized severe weather.
Given overall storm organization will be transient, the severe risk
appears isolated enough that a watch will not be needed.
..Lyons/Gleason.. 03/14/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...MLB...KEY...TBW...
LAT...LON 26897991 25948002 25118029 25118068 25278112 25588123
25908165 26168168 26688143 27768116 27998080 27928029
27328002 26897991
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1116 AM CDT Sat Mar 14 2026
Valid 141630Z - 151200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN FLORIDA PENINSULA...
...SUMMARY...
Isolated severe hail and gusty winds may occur with thunderstorms
that develop across parts of the southern Florida Peninsula this
afternoon.
...Florida...
Isolated to scattered thunderstorms should develop this afternoon
across parts of the FL Peninsula and the Keys, with agitated cu
noted on recent visible satellite imagery across east-central to
southeast FL. Greater low-level moisture is present across
central/south FL, where 60s to low 70s surface dewpoints exist per
latest observations. Continued daytime heating of this moist airmass
will support the development of moderate instability through the
afternoon. Modest mid-level lapse rates (reference 00Z MFL and 12Z
KEY observed soundings) and weak low/mid-level winds may tend to
limit updraft strength. Even so, modestly enhanced upper-level winds
and related deep-layer shear around 25-30 kt could support isolated
severe hail and gusty downdraft winds with the strongest cores that
develop. Have added a Marginal Risk for this potential across parts
of the southern FL Peninsula and vicinity where the greatest
concentration of convection is expected.
...Northern Rockies/High Plains...
Moisture will remain meager today (surface dewpoints generally in
the teens and 20s) across the northern Rockies and High Plains as an
upper trough amplifies and a surface cold front advances southward
over this region. Even so, cold temperatures aloft may support very
weak MUCAPE and occasional lightning flashes with low-topped
convection that should develop from eastern ID/southern MT into much
of WY and vicinity this afternoon/evening. While gusty winds may
occur with this activity, the very limited thermodynamic environment
should preclude organized severe thunderstorms.
...Upper Midwest...
Low-level warm/moist advection will increase tonight into early
Sunday morning across parts of the Upper Midwest as a
south-southwesterly low-level jet strengthens. Weak MUCAPE
(generally less than 1000 J/kg) along and north of a warm front and
strong large-scale ascent preceding the upper trough ejecting
eastward over the northern Plains may support elevated thunderstorms
late tonight (mainly after 15/06Z) across parts of IA/MN/WI. Small
hail could occur with the strongest cores, and lightning flashes
appear possible with mixed/wintry precipitation well north of the
warm front into MN/WI.
..Gleason/Lyons.. 03/14/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Sat Mar 14 2026
Valid 142000Z - 151200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN FLORIDA PENINSULA...
...SUMMARY...
Isolated severe hail and gusty winds may occur with thunderstorms
that develop across parts of the southern Florida Peninsula this
afternoon.
...20Z Update...
No changes to the ongoing forecast are necessary. Recent observed
soundings from central/south Florida showed potential for marginally
severe storms, though a mid-level subsidence layer was noted with
northern extent. Additional short-term details can be found in MD
#237.
..Wendt.. 03/14/2026
.PREV DISCUSSION... /ISSUED 1116 AM CDT Sat Mar 14 2026/
...Florida...
Isolated to scattered thunderstorms should develop this afternoon
across parts of the FL Peninsula and the Keys, with agitated cu
noted on recent visible satellite imagery across east-central to
southeast FL. Greater low-level moisture is present across
central/south FL, where 60s to low 70s surface dewpoints exist per
latest observations. Continued daytime heating of this moist airmass
will support the development of moderate instability through the
afternoon. Modest mid-level lapse rates (reference 00Z MFL and 12Z
KEY observed soundings) and weak low/mid-level winds may tend to
limit updraft strength. Even so, modestly enhanced upper-level winds
and related deep-layer shear around 25-30 kt could support isolated
severe hail and gusty downdraft winds with the strongest cores that
develop. Have added a Marginal Risk for this potential across parts
of the southern FL Peninsula and vicinity where the greatest
concentration of convection is expected.
...Northern Rockies/High Plains...
Moisture will remain meager today (surface dewpoints generally in
the teens and 20s) across the northern Rockies and High Plains as an
upper trough amplifies and a surface cold front advances southward
over this region. Even so, cold temperatures aloft may support very
weak MUCAPE and occasional lightning flashes with low-topped
convection that should develop from eastern ID/southern MT into much
of WY and vicinity this afternoon/evening. While gusty winds may
occur with this activity, the very limited thermodynamic environment
should preclude organized severe thunderstorms.
...Upper Midwest...
Low-level warm/moist advection will increase tonight into early
Sunday morning across parts of the Upper Midwest as a
south-southwesterly low-level jet strengthens. Weak MUCAPE
(generally less than 1000 J/kg) along and north of a warm front and
strong large-scale ascent preceding the upper trough ejecting
eastward over the northern Plains may support elevated thunderstorms
late tonight (mainly after 15/06Z) across parts of IA/MN/WI. Small
hail could occur with the strongest cores, and lightning flashes
appear possible with mixed/wintry precipitation well north of the
warm front into MN/WI.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Sat Mar 14 2026
Valid 151200Z - 161200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS IN THE
ARK-LA-TEX/ARK-LA-MISS TO THE WABASH/LOWER OH VALLEYS...
...SUMMARY...
Scattered to widespread damaging winds along with tornadoes should
develop on Sunday afternoon, persisting through Sunday night across
a large portion of the South-Central/Southeast States into the
Midwest/Ohio Valley. The greatest strong tornado and significant
severe wind threats appear to be from the Ark-La-Miss to the Lower
Ohio Valley on Sunday evening.
...Synopsis...
An upper trough will amplify across the central states on Sunday and
become centered from WI to the Ark-La-Tex by 12Z Monday. Associated
surface cyclone will track from the IA/MO border to Lower MI,
deepening Sunday evening/night. As this occurs, attendant cold front
will accelerate eastward across the Mid-MS to the OH Valleys.
Trailing portion of the front will sweep south-southeast into the
northwest Gulf to central Gulf Coast through Monday morning.
Primary changes with the level 3-ENH risk are to include a
10-percent tornado area, southward expansion of 45-percent wind, and
addition of 15-percent and CIG1 hail areas. Expansion of level
1-2/MRGL-SLGT risk areas has occurred over the Southeast for mainly
the 06-12Z period Monday. Uncertainty is greatest on the western
extent for where convection should become severe, and the northern
extent within a thermodynamically challenged environment.
...South-Central/Southeast States to the Midwest...
In the wake of morning elevated convection over a portion of the
Mid/Upper MS Valley, midday convective development should occur
along the highly convergent surface front across a part of the
Mid-MS Valley to the Ozarks. This activity may initially remain
shallow, before deepening and greatly expand in coverage through the
afternoon as it impinges on richer boundary-layer moisture towards
the Ark-La-Tex and the Mid-South portion of the MS Valley. By late
afternoon, an extensively long QLCS should become established from
IL south-southwestward. Semi-discrete supercell development appears
most favored along the southern portion of the broader convective
plume near the front and downstream within a strengthening
warm/moist conveyor. This should support potential for large hail
and a couple strong tornadoes before supercells become absorbed
within the broader QLCS during the evening. This scenario should
also yield an increasingly pinched-off warm-moist sector from the
Mid-South to TN Valley. Despite this aspect, substantial
strengthening of 700-mb winds on either side of the front, initially
across the Mid-South vicinity and expanding to the OH to TN Valleys,
will yield a setup conductive for scattered to widespread damaging
wind swaths through the evening.
On Sunday night, the northern extent of the severe threat should
become more sporadic as surface-based instability becomes/remains
minimal. But the very fast lower-level wind fields may yield
persistence of some damaging wind/brief tornado potential eastward
in the OH Valley/southern Great Lakes. Farther south, there are
increasing signals for renewed low-level warm conveyor convective
development across the central to northeast Gulf Coast vicinity
early Monday morning. Deep-layer shear profiles will be conducive to
semi-discrete supercells just ahead of/merging into the progressive
QLCS. This should foster a period of increased large hail/sustained
tornado potential. Otherwise, damaging winds will remain favored
from at least the FL Panhandle to the southern Appalachians.
..Grams.. 03/14/2026
|
