ACUS11 KWNS 152028
SWOMCD
SPC MCD 152027=20 KYZ000-INZ000-ILZ000-TNZ000-MSZ000-MOZ000-ARZ000-LAZ000-152200-

Mesoscale Discussion 0246
NWS Storm Prediction Center Norman OK
0327 PM CDT Sun Mar 15 2026

Areas affected...northeast Louisiana and northern/central
Mississippi to southern Illinois and Indiana.

Concerning...Severe potential...Tornado Watch likely=20

Valid 152027Z - 152200Z

Probability of Watch Issuance...95 percent

SUMMARY...A tornado watch will likely be needed in the next 1 to 2
hours.

DISCUSSION...Low 60F dewpoints have now moved into the Lower
Mississippi River Valley where temperatures have also warmed into
the upper 70s to low 80s. As low-level moisture continues to
increase and temperatures cool aloft across this region, expect
moderate surface based instability to develop by late afternoon. As
forcing overspreads this region ahead of the approaching mid-level
jet streak, supercells may develop during the late afternoon to
early evening period. These supercells would have some hail threat,
including the potential for large (2+ inch) hail.=20

The KNQA VWP already shows significant curvature in the lowest 2.5
km and the hodograph size is expected to grow through the
afternoon/evening as 850/700mb flow strengthens. Therefore, if these pre-frontal supercells form, they will also have a tornado threat,
with some potential for strong tornadoes.

By later in the evening, the damaging wind threat will increase
substantially as the front approaches the region. Convection along
the front this afternoon remains somewhat weak, primarily due to the
cool temperatures and limited moisture, but this activity is
expected to strengthen substantially as it interacts with the warmer
air and greater instability across eastern Arkansas and into
southeast Missouri this evening. Around this time, model guidance
continues to show a northward transport of 62-64F dewpoints into
this region which would result in a substantial QLCS tornado threat
in addition to the damaging wind threat.

A watch will be needed ahead of the approaching squall line, and may
need to be issued soon if pre-frontal supercell development appears
imminent.

..Bentley/Gleason.. 03/15/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9Tm2Ds84_iNxllPGrgy1TF6OVKIwIkrok4rZG-Vi2LXTTuvm2OlTKwLuyHaBShei9CG--fhNM= nYsA1VJ90Gke5WVN6k$ for graphic product...

ATTN...WFO...PAH...MEG...JAN...

LAT...LON 33259141 33649093 34139083 36049068 36599065 37368996
37858949 38228900 38448830 38308755 37668741 36858804
36448816 36048818 34778849 33548868 32838977 32539148
32899174 33259141=20

MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


=3D =3D =3D
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