No watches are valid as of Sat Feb 28 19:49:01 UTC 2026.No Mesoscale Discussions are in effect as of Sat Feb 28 19:49:01 UTC 2026.SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1012 AM CST Sat Feb 28 2026
Valid 281630Z - 011200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS CROSS PARTS OF
THE CENTRAL/SOUTHERN FLORIDA PENINSULA...
...SUMMARY...
Isolated strong to severe thunderstorms may occur across parts of
the central/southern Florida Peninsula this afternoon and evening.
...Central/Southern Florida Peninsula...
Late morning surface analysis places a cold front near the I-4
corridor across the central portion of the Peninsula, with upper 60s
to lower 70s dewpoints south of the boundary. A mid-level vorticity
maximum over MS/AL this morning is forecast to continue
east-southeastward through the base of a larger-scale eastern US
trough and eventually reach the Gulf Stream east of GA and
southwestward to the southern 1/3 of the Peninsula by early Sunday
morning. As this impulse progresses towards the region, the
aforementioned front will slowly move south. This boundary, a
residual outflow boundary, and an east-coast sea breeze will help
focus thunderstorm development and a potential severe risk this
afternoon. Ample heating of the moist boundary layer beneath a weak
cap, which will continue to erode by early to mid afternoon, will
result in 1500-2000 J/kg MLCAPE. Low-level flow will likely remain
veered and relatively weak, but 30+ kt shear in the 700-300 mb layer
will support some updraft organization. Scattered thunderstorms are
forecast to develop in the 18-20z period with a some of the stronger
storms potentially being capable of 55-65 mph gusts and 1 to 1.75
inch diameter hail. Short-term CAM guidance suggests the most
concentrated corridor for severe may extend from the north side of
Lake Okeechobee, where an agitated cumulus field is developing along
the diffuse outflow boundary, southward into Broward/Palm Beach
counties. Convection is forecast to eventually move east into the
Atlantic this evening with the severe risk diminishing.
...Oklahoma...
Weak MUCAPE should develop by this afternoon/early evening across
parts of OK near a surface trough. A low-amplitude shortwave trough
embedded within broad cyclonic flow over the central/eastern CONUS
may support isolated thunderstorm development across this area in
tandem with peak afternoon heating. Instability should remain too
weak to support an organized severe threat with this activity,
although locally strong/gusty winds and small hail appear possible
given steepened low-level lapse rates and favorably strong
deep-layer shear.
...Northern California...
A mid-level shortwave trough will move east-northeastward today
across northern CA and vicinity. Cool temperatures aloft associated
with this shortwave trough combined with generally 40 to mid 50s
surface dewpoints and filtered daytime heating should promote around
500-750 J/kg of MUCAPE over this region by mid to late afternoon.
While a couple of stronger thunderstorms may form across this area,
the overall severe threat should tend to be limited by the weak
instability.
..Smith/Leitman.. 02/28/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0145 PM CST Sat Feb 28 2026
Valid 282000Z - 011200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL AND SOUTH FLORIDA...
...SUMMARY...
Isolated strong to severe thunderstorms may occur across parts of
the central/southern Florida Peninsula this afternoon and evening.
...20Z Update...
Only minor changes to the general thunderstorm forecast in North
Florida were made base on current observations. Mid-level ascent is
entering the northeastern Gulf per visible/water-vapor satellite.
This should continue to promote potential for additional
thunderstorms within the central and southern Florida Peninsula. See
the previous discussion for additional details.
..Wendt.. 02/28/2026
.PREV DISCUSSION... /ISSUED 1012 AM CST Sat Feb 28 2026/
...Central/Southern Florida Peninsula...
Late morning surface analysis places a cold front near the I-4
corridor across the central portion of the Peninsula, with upper 60s
to lower 70s dewpoints south of the boundary. A mid-level vorticity
maximum over MS/AL this morning is forecast to continue
east-southeastward through the base of a larger-scale eastern US
trough and eventually reach the Gulf Stream east of GA and
southwestward to the southern 1/3 of the Peninsula by early Sunday
morning. As this impulse progresses towards the region, the
aforementioned front will slowly move south. This boundary, a
residual outflow boundary, and an east-coast sea breeze will help
focus thunderstorm development and a potential severe risk this
afternoon. Ample heating of the moist boundary layer beneath a weak
cap, which will continue to erode by early to mid afternoon, will
result in 1500-2000 J/kg MLCAPE. Low-level flow will likely remain
veered and relatively weak, but 30+ kt shear in the 700-300 mb layer
will support some updraft organization. Scattered thunderstorms are
forecast to develop in the 18-20z period with a some of the stronger
storms potentially being capable of 55-65 mph gusts and 1 to 1.75
inch diameter hail. Short-term CAM guidance suggests the most
concentrated corridor for severe may extend from the north side of
Lake Okeechobee, where an agitated cumulus field is developing along
the diffuse outflow boundary, southward into Broward/Palm Beach
counties. Convection is forecast to eventually move east into the
Atlantic this evening with the severe risk diminishing.
...Oklahoma...
Weak MUCAPE should develop by this afternoon/early evening across
parts of OK near a surface trough. A low-amplitude shortwave trough
embedded within broad cyclonic flow over the central/eastern CONUS
may support isolated thunderstorm development across this area in
tandem with peak afternoon heating. Instability should remain too
weak to support an organized severe threat with this activity,
although locally strong/gusty winds and small hail appear possible
given steepened low-level lapse rates and favorably strong
deep-layer shear.
...Northern California...
A mid-level shortwave trough will move east-northeastward today
across northern CA and vicinity. Cool temperatures aloft associated
with this shortwave trough combined with generally 40 to mid 50s
surface dewpoints and filtered daytime heating should promote around
500-750 J/kg of MUCAPE over this region by mid to late afternoon.
While a couple of stronger thunderstorms may form across this area,
the overall severe threat should tend to be limited by the weak
instability.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1114 AM CST Sat Feb 28 2026
Valid 011200Z - 021200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms will be possible on Sunday across parts of south
Florida, the southern and central Plains, and in northern California
Sunday afternoon and evening.
...Synopsis...
A strong cyclone traversing eastern Canada this morning will be
followed by strengthening surface high pressure across the eastern
two-thirds of the CONUS tomorrow. A weak trailing cold front
associated with the Canadian cyclone will gradually migrate south
into the Southeast and southern Plains. Isentropic ascent over the
frontal zone will support isolated thunderstorms across portions of
OK into southeast KS, southwest MO, and northwest AR tomorrow
afternoon and evening. Although the kinematic environment is
conditionally favorable for organized convection, meager moisture
return and poor mid-level lapse rates should mitigate severe
thunderstorm potential. There is a low chance for a strong
thunderstorm across central OK during the evening hours per latest
RRFS solutions, which depict better low-level moisture/buoyancy into
OK and are aligned with recent RAP solutions environmentally.
However, the consensus among other HREF members and calibrated
guidance is that the RRFS is the outlier solution, which
substantially limits confidence in the severe potential.
Elsewhere, lingering showers and isolated thunderstorms are expected
within a residual frontal zone across the southern FL Peninsula
where an unstable, but weakly capped, environment should be in
place. Along the West Coast, an upper-level trough pushing into
northern CA and southern OR will support isolated thunderstorms as
instability increases due to cooling temperatures aloft within a
fairly moist air mass.
..Moore.. 02/28/2026
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