RSS Mesoscale Discussions from Storm Prediction Center
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 AM CDT Fri Mar 27 2026
Valid 291200Z - 301200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms are possible across the southern Florida
peninsula and portions of southern Arizona Sunday afternoon and
evening. Severe thunderstorms are not expected.
...Synopsis...
An upper-level ridge (currently in place over the Southwest) is
forecast to shift east over the Plains through the day Sunday.
Broad-scale subsidence/height rises ahead of the ridge will promote
mostly dry and stable conditions for the central and eastern CONUS.
Thunderstorm potential will most likely be relegated to the southern
FL peninsula where weak ascent within a residual frontal zone (aided
by diurnally-drive sea breeze boundaries) may support a few
thunderstorms within a moist and weakly capped environment. While
confidence is lower, isolated convection appears possible across
parts of southern Arizona late Sunday afternoon where modest
low-level moisture advection, coupled with ample daytime heating,
steep mid-level lapse rates, and weak ascent from a mid-level
impulse may support high-based convection. Based on forecast
thermodynamic profiles, conditions may be supportive of strong
downburst winds. However, confidence in storm coverage and the
severe wind potential is too low for highlights.
..Moore.. 03/27/2026
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Fri Mar 27 2026
Valid 301200Z - 041200Z
...DISCUSSION...
An uptick in severe thunderstorm potential is expected through the
upcoming work week and heading into next weekend. Long-range
ensemble guidance continues to show a strong signal for a return to
mean troughing across the western to central CONUS as a long-wave
ridge gradually de-amplifies and shifts east. This upper-level flow
regime will promote steady lee troughing/cyclogenesis along the High
Plains, which in conjunction with the placement of a surface high
off the East Coast, will promote moisture return northward into the
Plains and MS Valley. Strong to severe thunderstorms appear possible
multiple days next week as ascent associated with upper disturbances
embedded within the mean flow regime overspread the moisture plume.
...D4/Monday - Upper Mississippi Valley...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border during the D4/Monday to D5/Tuesday time frame. As this
occurs, surface cyclogenesis is expected across the northern Plains.
A broad swath of isentropic ascent with in the warm conveyor of the
developing cyclone will likely support showers and isolated to
scattered thunderstorms across portions of the upper MS Valley late
Monday. A few deterministic solutions, notably the recent 00z ECMWF,
hint that the convective environment will be conducive for organized
convection, including the potential for elevated supercells.
However, ensemble agreement regarding this potential is limited.
...D5/Tuesday - Lake Michigan Vicinity...
Confidence is gradually increasing in a regional severe weather
threat across parts of the upper Great Lakes for D5/Tuesday. Over
the past 24 hours, model guidance has come into somewhat better
agreement regarding the timing and evolution of the northern Plains
surface low through as it translates east and intensifies across the
Great Lakes region Tuesday into early Wednesday. Above-seasonal
moisture return northward into the Great Lakes region is anticipated
by late Tuesday, which should support adequate buoyancy for deep
convection. Thunderstorm development appears likely along a trailing
cold front as it pushes southeast into the Midwest and MS Valley.
Based on ensemble guidance, the best convective environment may
reside across the Lake Michigan vicinity where mid/upper-level flow
should be stronger in vicinity to the upper jet and may be more
orthogonal to the front and supportive of more robust convection
compared to locations further south.
Despite the trend towards a more consolidated solution, notable
discrepancies remain pertaining to the propagation speed of the
upper wave and surface low, which introduces uncertainty in how
favorably timed the strongest ascent will be with peak
heating/destabilization and potential storm modes. These
uncertainties preclude probabilities at this time, but highlights
will likely be introduced as model consensus improves.
Read more
