RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sun Mar 15 06:31:01 UTC 2026.
MD 0240 CONCERNING HEAVY SNOW FOR FAR NORTHWEST IOWA...SOUTHERN MINNESOTA...AND CENTRAL WISCONSIN
Mesoscale Discussion 0240
NWS Storm Prediction Center Norman OK
1155 PM CDT Sat Mar 14 2026
Areas affected...Far northwest Iowa...southern Minnesota...and
central Wisconsin
Concerning...Heavy snow
Valid 150455Z - 151000Z
SUMMARY...Heavy snow banding will become more prominent in the
coming hours across extreme northwest Iowa, southern Minnesota, and
into central Wisconsin. Snowfall rates will likely exceed 2 inches
per hour within a narrow band across the region.
DISCUSSION...An intensifying cyclone is apparent in surface
observations over the central Plains as a prominent upper-level jet
continues to push southeast. Recent VWP observations across the
eastern Plains have shown a pronounced increase in low-level winds
(upwards of 50-60 knots at 1 km AGL) within the developing warm
conveyor belt of the emerging cyclone. Concurrently, an increase in
precipitation is noted from southwest NE into southeast SD as the
strengthening low-level winds augment isentropic ascent as well as
low to mid-level frontogenesis.
In the coming hours, strong isentropic ascent and more focused lift
within the frontogenetical circulation between 850-700 mb will shift
east/northeast into southern MN and central WI as the surface
cyclone begins to migrate east/northeast. Ascent through a deep
layer, including through a somewhat shallow dendritic growth zone,
will support a broad swath of heavy snowfall rates in excess of 1
inch/hour.
A combination of focused ascent within a frontogenetical 700 mb
deformation zone and periodic convective augmentation (8.8 C/km
mid-level lapse rates were noted in an upstream 00z OAX sounding and
should be advecting into the southern flank of the deformation zone)
will likely result in a narrow corridor of snowfall rates between
2-3 inches/hour. Based on a consensus of recent guidance, this band
will most likely emerge across southern MN into central WI during
the 07-11 UTC time frame and will likely persist well into the
mid-morning hours.
..Moore.. 03/15/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MQT...GRB...DLH...ARX...MPX...DMX...FSD...
LAT...LON 45338876 45318807 45178757 45028729 44778720 44338741
44068759 44078813 44149025 44169073 44049130 43519322
43169443 43079499 43159547 43409578 43699585 43969558
44469481 44809414 45149324 45339221 45389097 45338876
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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1252 AM CDT Sun Mar 15 2026
Valid 151200Z - 161200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS
AFTERNOON THROUGH TONIGHT ACROSS PARTS OF THE MID SOUTH INTO LOWER
OHIO VALLEY AND ACROSS PARTS OF THE EASTERN GULF COAST STATES...
...SUMMARY...
Widespread strong to severe wind gusts may accompany a developing
squall line across and east of the middle into lower Mississippi
Valley late this afternoon into this evening. A couple of strong
tornadoes are also possible within and just ahead of this line
across parts of the lower Ohio Valley into Mid South, with a couple
of strong tornadic supercells also possible across parts of the
Florida Panhandle and southeastern Alabama into adjacent Georgia
late tonight.
...Discussion...
To the north of an expanding blocking mid-level high, centered off
the southern California coast, models indicate that large-scale
ridging will continue to build inland of the British Columbia/U.S.
Pacific coast, through the Canadian Rockies and U.S. Intermountain
West during this period. Downstream, a significant short wave
trough is forecast to continue amplifying southeastward across the
Great Plains and Mississippi Valley, preceded by building ridging
near and east of the Atlantic Seaboard.
Downstream of the digging short wave trough, a broad and deep
cyclone has already formed to the east of the Colorado Rockies, with
a plume of warm elevated mixed-layer air overspreading the central
and southern Great Plains toward the lower Mississippi Valley. The
center of the cyclone is forecast to redevelop east-northeast into
the St. Joseph MO vicinity by daybreak, before continuing to deepen
while migrating northeastward toward lower Michigan today through
tonight. It appears that the northeastern periphery of the elevated
mixed-layer plume will spread across the lower Missouri Valley
before becoming suppressed southeastward.
In the wake of a preceding surface cyclone and associated cold
frontal passage, Gulf boundary-layer moistening and inland return
flow remain limited at this time. Although it should improve some,
aside from a narrow corridor of better boundary-layer moisture
return across the southeastern Great Plains toward the lower Ohio
Valley, and broader corridors across the southern through middle
Atlantic Seaboard, as well as across the eastern Gulf Coast vicinity
by late tonight, warm sector dew points may not exceed lower/mid 50s
F. This may prove a limiting factor to the overall severe threat.
Nevertheless, guidance continues to indicate the development of a
fairly extensive squall line along much of the length of a cold
front advancing across and east of the Mississippi Valley toward the
Appalachians late this afternoon through tonight.
...Lower Mississippi Valley into Great Lakes...
Latest model output suggests that the stronger 850 mb jet core may
tend to shift ahead of the deepening surface cyclone, north of the
Ohio Valley into and through the lower Great Lakes region during the
afternoon. However, 40-50+ kt southerly flow may tend to trail back
ahead of the cold front to the southwest, at least as far as the Mid
South vicinity through late afternoon, as a narrow corridor of
better boundary-layer moisture return (characterized by lower 60s F
surface dew points) surges across northeastern Arkansas and
southeastern Missouri into southern Illinois, western Kentucky and
Tennessee.
North-northeast and east of this vicinity, toward the Great Lakes
and upper Ohio Valley, the narrow corridor of better pre-frontal
moisture is likely to be more modest and supportive of rather modest
to weak CAPE. And there is concern that deeper boundary-layer
warming and mixing in the drier pre-convective environment may
actually be more efficient at mixing down stronger momentum to the
surface than the thunderstorm activity.
However, based on the latest forecast soundings, there does still
appear potential for widespread potentially damaging wind gusts at
least approaching or exceeding 50 kts, with an evolving pre-frontal
squall line as it spreads across and east of the middle to lower
Mississippi Valley vicinity. Gusts exceeding 65 kts, and potential
for tornadoes, may tend to be confined to meso-vortices evolving
along the leading edge of the convective outflow, particularly
within the more moist environment across the lower Ohio Valley into
Mid South.
There may also be a late afternoon into early evening window of
opportunity, across this same corridor, for either initially
discrete supercell development or discrete supercell development
just ahead of the evolving eastward advancing line. If this occurs,
there will probably be at least somewhat greater potential for
strong tornadoes. However, this remains unclear, particularly given
the limited breadth of the moist sector, and the tendency for it to
be rather quickly overtaken by the cold front.
...Eastern Gulf Coast States...
Models continue to indicate a separate area of better low-level
moisture return across the eastern Gulf coast, which may include
surface dew points increasing through the lower/mid 60s across the
western Florida Panhandle, southeastern Alabama and adjacent Georgia
by late tonight. It appears that this will support a corridor of
boundary-layer destabilization characterized by CAPE in excess of
1000 J/kg. Coincident with enlarging, clockwise curved low-level
hodographs beneath 40-45 kt southwesterly 850 mb flow overspreading
the region, and in the presence of sufficient deep-layer shear,
there appears potential for the evolution of longer-lived supercells
which could become capable of producing strong tornadoes.
..Kerr/Thornton.. 03/15/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0107 AM CDT Sun Mar 15 2026
Valid 161200Z - 171200Z
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
SOUTH CAROLINA ACROSS NORTH CAROLINA AND INTO VIRGINIA AND
MARYLAND...
...SUMMARY...
Widespread severe storms are forecast on Monday for parts of the
Mid-Atlantic States and Southeast. Tornadoes, potentially strong,
and particularly damaging winds are most likely from South Carolina
into Maryland during the afternoon. Significant severe storm
potential overall will extend from eastern Georgia/Florida Panhandle
into Pennsylvania.
...Synopsis...
A large and deepening upper trough will pivot northeastward out of
the OH/TN Valleys, across the Appalachians and into the Mid Atlantic
on Monday, while a surface low deepens into southern Quebec. A sharp
pre-frontal trough will extend southward across NY, PA, and into the
Carolinas/GA by late afternoon, with a corridor of significant
pressure falls timed with the diurnal heating maximum. A cold front
will push rapidly east across GA and the FL Panhandle during the day
with a bit slower progress across the Piedmont and into PA. Gusty
south winds ahead of the cold front will maintain 60s F dewpoints
across the entire region, and as far north as southern PA, just
after warm front passage by late afternoon.
Just above the surface, southerly 850 mb winds will increase from 50
to 75 kt, resulting in extreme shear profiles over a large area.
Large-scale ascent and shear will increase coincident with the peak
heating hours, resulting in a potentially widespread severe weather
event during the afternoon.
...From Georgia and the Florida Panhandle...
Early day storms may be ongoing from the southern Appalachians
toward the FL Panhandle Monday morning, and the environment will
already be favorable for supercells including tornado potential.
Forecast soundings indicate substantial instability with mid to
perhaps upper 60s F along with ample shear. These storms may also
produce hail, as midlevel lapse rates approach 7 C/km.
...Carolinas into MD/PA and vicinity...
Areas of showers may occur early in the day especially but should
rapidly lift north, allowing areas of heating and gradual
destabilization over the entire area. As the surface trough deepens,
low-level wind will back and strengthen throughout the day.
Supercells producing tornadoes appear most likely ahead of the cold
front from SC into NC and southern VA. Models vary with degree of
instability, but strong tornadoes do appear possible with effective
SRH of at least 300-400 m2/s2. Fast storm motions over 50 kt suggest
a long tracked tornado will be possible.
Meanwhile, a robust line of storms will develop as the cold front
pushes east, stretching from the Carolinas to southern NY. With a
moist air mass and large-scale support, this line is expected to
produce particularly damaging winds, along with QLCS tornadoes
across the remainder of SC/NC, VA, MD, and much of southern PA. This
will likely peak during the late afternoon hours. The activity may
eventually interact with cool trajectories off the Atlantic during
the evening.
..Jewell.. 03/15/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1252 AM CDT Sun Mar 15 2026
Valid 151200Z - 161200Z
...CRITICAL FIRE WEATHER AREA FOR MUCH OF NEW MEXICO...WESTERN TEXAS
AND SOUTHWESTERN OKLAHOMA...
...Synopsis...
A strengthening and dynamic low pressure system will move eastward
through the Missouri/Ohio Valley into the Great Lakes today. On the
backside of this low, strong westerly gradients will support
enhancement of westerly surface flow ahead of a southward moving
cold front across the southern High Plains. Behind the front, a
shift to strong north to northwesterly flow is likely. Multiple
periods of Elevated to Critical fire weather conditions will be
possible across much of New Mexico into western and southwestern
Oklahoma.
...New Mexico, Western Texas and Far Southwestern Oklahoma...
Overnight recoveries across New Mexico and western Texas are
expected to be poor. As of 05z, observed relative humidity is in the
single digits to teens, with temperatures in the mid to upper 60s
and continued gusty winds. Forecast maximum overnight relative
humidity through the morning ranges around 25-30%. It is likely that
Elevated to Critical conditions will be ongoing at the start of the
new D1 period this morning. Through the afternoon ahead of the cold
front across New Mexico and southwest/west Texas, increasing
west-northwest winds at 20-30 mph will overlap relative humidity
reductions to around 10-15%. Localized Extremely Critical fire
weather conditions are possible across portions of central New
Mexico along and east of the Sandia Manzano Range under a 80-90 knot
mid-level jet max at the base of an advancing trough. The resultant
enhanced downslope regime where west-northwest winds of 30-40 mph
with higher gusts coincide with relative humidity falling to around
10% should align with receptive fuels (ERC in the 80-90th percentile
range) to support this localized Extremely Critical threat, although
uncertainty in cloud cover and coverage precludes introduction of
Extremely Critical Highlights for this update.
Behind the cold front passage across the Texas Panhandle into
southwestern Oklahoma, temperatures cool and relative humidity will
briefly improve with a shift in the winds from westerly to
northerly. Deteriorating fire weather conditions will reemerge a few
hours later as surface dewpoints fall close to 0 F across the
southern High Plains. This will result in 15% or lower relative
humidity by peak afternoon heating amid 25-35 mph north/northwest
winds. This could have a considerable impact on active wildfires in
receptive fuels should they occur, particularly across Northwest TX
where the driest post-frontal conditions and higher winds align. The
overall fire weather threat shifts into Southern TX/Lower Rio Grande
Valley region Sunday evening, potentially lingering into the
overnight hours.
..Thornton.. 03/15/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Sun Mar 15 2026
Valid 161200Z - 171200Z
...Synopsis...
Post frontal northerly flow will shift into southern/central Texas
for D2/Monday, with Elevated fire weather conditions expected. Dry
return flow will bring Elevated fire weather concerns across eastern
New Mexico into western Texas as a high builds across the southern
Plains and moves into the lower Mississippi River Valley.
...Eastern New Mexico into west Texas...
Across eastern New Mexico into western Texas, south to southeast
winds 10-15 mph will overlap relative humidity reductions to around
15-20%. An Elevated was maintained with this outlook to support this
threat. Fuels in this region are expected to be critically dry after
multiple days of dry/wind conditions.
...Southern/Central Texas...
Behind the southward advancing cold front, relative humidity
reductions to around 15-25% (locally around 10% in south Texas) will
overlap sustained north winds at 10-20 mph across portions of the
south Texas Brush Country to the Rio Grande Valley and across the
Middle Texas Coast. The D3 40 percent was maintained and expanded
across the coast with this update. Fuels across the south Texas
Brush Country are critically dry, with ERCs forecast to be around
the 75-90th percentile. Fuels across the middle Texas coast region
are more marginal but are forecast to be around the 50-75th
percentile by D2/Monday.
..Thornton.. 03/15/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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