WW 163 TORNADO IL 272140Z - 280200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 163
NWS Storm Prediction Center Norman OK
440 PM CDT Mon Apr 27 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Central Illinois
* Effective this Monday afternoon and evening from 440 PM until
900 PM CDT.
* Primary threats include...
Several tornadoes and a couple intense tornadoes likely
Widespread damaging winds likely with isolated significant gusts
to 75 mph possible
Scattered large hail likely with isolated very large hail events
to 2.5 inches in diameter possible
SUMMARY...A remnant boundary left over by overnight/early morning
storms will be an initial focus for intense storm development
including supercells, with additional storms developing later
afternoon across broader parts of the region. All severe weather
hazards all possible, including strong/intense tornadoes.
The tornado watch area is approximately along and 45 statute miles
north and south of a line from 50 miles west of Springfield IL to 25
miles south of Danville IL. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU3).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 159...WW 160...WW
161...WW 162...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2.5 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean
storm motion vector 28025.
...Mosier
WW 162 TORNADO AR IL IN KY MO TN 271945Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 162
NWS Storm Prediction Center Norman OK
245 PM CDT Mon Apr 27 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Northeast Arkansas
Southern Illinois
Southern Indiana
Western Kentucky
Southeast Missouri
Western Tennessee
* Effective this Monday afternoon and evening from 245 PM until
1100 PM CDT.
...THIS IS A PARTICULARLY DANGEROUS SITUATION...
* Primary threats include...
Several tornadoes and a few intense tornadoes likely
Scattered large hail likely with isolated very large hail events
to 2.5 inches in diameter possible
Scattered damaging wind gusts to 70 mph likely
SUMMARY...Intense supercell development is expected to occur through
late afternoon, with a multi-round of severe storms expected to
occur across much of the region through this evening. As
deep-layer/low-level winds continue to strengthen, this includes the
potential for tornadoes, such of which are likely to be
strong/intense (EF2+/EF3+). Large hail and damaging winds are also
expected.
The tornado watch area is approximately along and 80 statute miles
east and west of a line from 45 miles west northwest of Evansville
IN to 10 miles east of Memphis TN. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU2).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 158...WW 159...WW
160...WW 161...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean
storm motion vector 25025.
...Guyer
WW 161 SEVERE TSTM AR KS MO OK 271910Z - 280200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 161
NWS Storm Prediction Center Norman OK
210 PM CDT Mon Apr 27 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northwest Arkansas
Southeast Kansas
Western Missouri
Northeast Oklahoma
* Effective this Monday afternoon and evening from 210 PM until
900 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2.5
inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...At least isolated severe thunderstorms should further
develop across the region within a very unstable environment in the
presence of strong deep-layer winds.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 50 miles south
southwest of Chanute KS to 45 miles north northeast of Springfield
MO. For a complete depiction of the watch see the associated watch
outline update (WOUS64 KWNS WOU1).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 158...WW 159...WW 160...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
24025.
...Guyer
WW 160 TORNADO IL MO 271750Z - 280200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 160
NWS Storm Prediction Center Norman OK
1250 PM CDT Mon Apr 27 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Southern Illinois
Eastern and Southern Missouri
* Effective this Monday afternoon and evening from 1250 PM until
900 PM CDT.
* Primary threats include...
Several tornadoes and a couple intense tornadoes likely
Widespread damaging winds likely with isolated significant gusts
to 75 mph possible
Scattered large hail likely with isolated very large hail events
to 2.5 inches in diameter possible
SUMMARY...A remnant boundary left over by overnight/early morning
storms will be an initial focus for intense storm development
including supercells, with additional storms developing later
afternoon across broader parts of the region. All severe weather
hazards all possible, including strong/intense tornadoes.
The tornado watch area is approximately along and 65 statute miles
north and south of a line from 15 miles north of Springfield MO to
45 miles east of Salem IL. For a complete depiction of the watch see
the associated watch outline update (WOUS64 KWNS WOU0).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 158...WW 159...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2.5 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean
storm motion vector 28025.
...Guyer
WW 159 SEVERE TSTM IL IN KY 271610Z - 272300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 159
NWS Storm Prediction Center Norman OK
1110 AM CDT Mon Apr 27 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast Illinois
Southern and Central Indiana
Northern Kentucky
* Effective this Monday morning and evening from 1110 AM until
600 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Scattered large hail events to 1.5 inches in diameter possible
A tornado or two possible
SUMMARY...Elevated storms will spread generally eastward and
potentially pose a hail risk while damaging wind risk may increase
into western/southern Indiana as well as an upstream linear cluster
of storms moves into the region.
The severe thunderstorm watch area is approximately along and 35
statute miles east and west of a line from 15 miles east of
Lafayette IN to 20 miles west southwest of Owensboro KY. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 158...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
27025.
...Guyer
WW 0163 Status Updates
STATUS FOR WATCH 0163 HAS NOT BEEN ISSUED YET
WW 0162 Status Updates
STATUS FOR WATCH 0162 HAS NOT BEEN ISSUED YET
WW 0161 Status Updates
STATUS FOR WATCH 0161 HAS NOT BEEN ISSUED YET
WW 0160 Status Updates
STATUS REPORT ON WW 160
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..HART..04/27/26
ATTN...WFO...LSX...ILX...PAH...SGF...
STATUS REPORT FOR WT 160
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC005-013-025-027-033-047-049-051-055-065-077-079-081-083-101-
117-119-121-133-135-145-157-159-163-189-191-193-272040-
IL
. ILLINOIS COUNTIES INCLUDED ARE
BOND CALHOUN CLAY
CLINTON CRAWFORD EDWARDS
EFFINGHAM FAYETTE FRANKLIN
HAMILTON JACKSON JASPER
JEFFERSON JERSEY LAWRENCE
MACOUPIN MADISON MARION
MONROE MONTGOMERY PERRY
RANDOLPH RICHLAND ST. CLAIR
WASHINGTON WAYNE WHITE
MOC015-027-029-043-051-055-059-065-067-071-073-077-085-091-093-
099-105-113-123-125-131-135-139-141-149-151-153-157-161-167-169-
179-183-186-187-189-203-213-215-219-221-225-229-510-272040-
MO
. MISSOURI COUNTIES INCLUDED ARE
BENTON CALLAWAY CAMDEN
CHRISTIAN COLE CRAWFORD
WW 0159 Status Updates
STATUS REPORT ON WW 159
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 SW HUF TO
15 E HUF TO 25 NW IND TO 30 ENE IND.
..HART..04/27/26
ATTN...WFO...PAH...IND...LMK...
STATUS REPORT FOR WS 159
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC185-272040-
IL
. ILLINOIS COUNTIES INCLUDED ARE
WABASH
INC013-021-025-027-037-051-055-063-081-083-093-097-101-105-109-
117-119-123-125-129-133-147-153-163-173-272040-
IN
. INDIANA COUNTIES INCLUDED ARE
BROWN CLAY CRAWFORD
DAVIESS DUBOIS GIBSON
GREENE HENDRICKS JOHNSON
KNOX LAWRENCE MARION
MARTIN MONROE MORGAN
ORANGE OWEN PERRY
PIKE POSEY PUTNAM
SPENCER SULLIVAN VANDERBURGH
WARRICK
WW 0158 Status Updates
STATUS REPORT ON WW 158
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 E SLO TO
25 SSE MTO TO 20 SW HUF.
..HART..04/27/26
ATTN...WFO...LSX...ILX...DVN...
STATUS REPORT FOR WS 158
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC025-033-049-079-101-159-272040-
IL
. ILLINOIS COUNTIES INCLUDED ARE
CLAY CRAWFORD EFFINGHAM
JASPER LAWRENCE RICHLAND
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
MD 0575 CONCERNING TORNADO WATCH 162... FOR SOUTHERN IL...FAR WESTERN KY...AND FAR SOUTHWESTERN IN
Mesoscale Discussion 0575
NWS Storm Prediction Center Norman OK
0358 PM CDT Mon Apr 27 2026
Areas affected...Southern IL...far western KY...and far southwestern
IN
Concerning...Tornado Watch 162...
Valid 272058Z - 272230Z
The severe weather threat for Tornado Watch 162 continues.
SUMMARY...Monitoring for supercell development and the potential for
strong-intense tornadoes over the next couple hours.
DISCUSSION...Convection is gradually increasing across far southern
IL and vicinity, where boundary-layer dewpoints have increased to
near 70F -- resulting in a strongly unstable air mass. Additionally,
the PAH VWP and recent mesoanalysis data indicate a large
clockwise-curved hodograph, with effective SRH increasing to around
300 m2/s2. The strong buoyancy, enhanced low-level streamwise
vorticity, and expected discrete storm mode will favor an increasing
risk of supercells capable of producing strong-intense tornadoes and
very large hail/damaging winds over the next couple hours.
..Weinman.. 04/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...LSX...
LAT...LON 36958876 37078929 37438966 37768967 38138940 38388889
38438843 38438790 38028755 37598768 37048836 36958876
MOST PROBABLE PEAK TORNADO INTENSITY...140-170 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
MD 0574 CONCERNING TORNADO WATCH 160... FOR SOUTH-CENTRAL THROUGH EAST-CENTRAL MISSOURI INTO SOUTHWEST ILLINOIS
Mesoscale Discussion 0574
NWS Storm Prediction Center Norman OK
0355 PM CDT Mon Apr 27 2026
Areas affected...south-central through east-central Missouri into
southwest Illinois
Concerning...Tornado Watch 160...
Valid 272055Z - 272300Z
The severe weather threat for Tornado Watch 160 continues.
SUMMARY...The threat for all severe-weather hazards --including the
potential for strong tornadoes-- is expected to increase late this
afternoon into evening.
DISCUSSION...Recent trends in surface observations and radar data
indicate the outflow boundary south of the St. Louis metropolitan
area stalling with the western extent of that feature lifting north
in the Columbia, MO vicinity. PBL warming and moistening to the
north of the modifying boundary is resulting in rapid air mass
recovery within a kinematic environment featuring locally backed
surface winds with As such, rapid air mass recovery is ongoing along
to the north of the retreating outflow, which is coincident with a
corridor of enhanced low-level shear with effective SRH of 200-300
M2/s2.
The supercell ongoing to the immediate north of the St. Louis metro
is within the eastern fringe of the stronger destabilization amidst
a kinematic environment featuring around 250 m2/s2 of effective SRH
and around 60 kt of effective bulk shear. As such, the potential for
tornadoes will exist with that storm, at least in the near-term. The
longer-term tornado threat with that storm will be contingent on
sufficient destabilization of the downstream air mass to the north
of the fresher segment of convective outflow.
At the same time, thunderstorms are increasing in areal coverage
along and ahead of a cold front moving through northwest and
west-central MO, where low-level winds have veered to southwesterly.
The leading edge of those storms will pose the greatest risk for
tornadoes as the continue northeast and encounter increasingly
stronger low-level shear near and to the north of the Columbia and
Mexico, MO vicinities.
In addition to the tornado threat, the potential for large to very
large hail will exist with any sustained supercells. Isolated
damaging wind gusts also remain possible.
..Mead.. 04/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ILX...LSX...SGF...
LAT...LON 37549338 38449280 39039228 39589173 39559093 39448977
39108902 38648892 38378953 37929032 37339128 36939162
36699225 36849270 37149328 37549338
MOST PROBABLE PEAK TORNADO INTENSITY...140-170 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
MD 0573 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR MUCH OF ARKANSAS INTO NORTHERN MISSISSIPPI
Mesoscale Discussion 0573
NWS Storm Prediction Center Norman OK
0324 PM CDT Mon Apr 27 2026
Areas affected...Much of Arkansas into northern Mississippi
Concerning...Severe potential...Tornado Watch likely
Valid 272024Z - 272300Z
Probability of Watch Issuance...80 percent
SUMMARY...Monitoring the area for increasing severe potential this
afternoon and evening. While timing is uncertain, one or more
Tornado Watches will likely be needed.
DISCUSSION...Boundary-layer cumulus is gradually deepening in
portions of southwestern AR and northern MS within a broad area of
low-level confluence. The SHV 18Z sounding sampled a strongly
unstable air mass (around 3400 J/kg SBCAPE), aided by steep midlevel
lapse rates atop a warm/moist boundary layer (lower 70s dewpoints).
While this buoyancy and 40-50 kt of effective shear (with
clockwise-curved low-level hodographs) will favor supercells capable
of producing very large hail, damaging winds, and tornadoes,
substantial capping at the base of the EML and nebulous forcing for
ascent cast uncertainty on timing of storm development.
Nevertheless, current thinking is that one or more Tornado Watches
will eventually be needed for the area, and convective/environmental
trends are being monitored.
..Weinman/Guyer.. 04/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MEG...JAN...LZK...SHV...TSA...
LAT...LON 34129407 34839406 35679375 36159316 36329268 36419196
36259135 35919107 35139100 34949070 34948978 34888894
34608871 34178875 33788912 33468983 33189097 33049231
33059307 33199352 33449386 33829408 34129407
MOST PROBABLE PEAK TORNADO INTENSITY...120-145 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0752 AM CDT MON APR 27 2026
...Severe thunderstorms expected over parts of the mid Mississippi
Valley and Mid-South today and tonight...
* LOCATIONS...
Southern and Central Illinois
Central and Eastern Missouri
Western Kentucky
Western Indiana
Northern and Central Arkansas
Western Tennessee
* HAZARDS...
Several tornadoes, a couple intense
Widespread damaging winds
Scattered large hail, some baseball size
* SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF-3+), widespread severe/damaging wind gusts, and scattered
large to very large hail.
Preparedness actions...
Review your severe weather safety procedures for the possibility
of dangerous weather today. Stay tuned to NOAA Weather Radio,
weather.gov, or other media for watches and warnings. A tornado
watch means that conditions are favorable for tornadoes to form
during the next several hours. If a tornado warning is issued for
your area, move to a place of safety, ideally in a basement or
interior room on the lowest floor of a sturdy building.
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1150 AM CDT Mon Apr 27 2026
Valid 271630Z - 281200Z
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS
EAST/SOUTHEAST MISSOURI...SOUTHERN ILLINOIS...WESTERN KENTUCKY...AND
NORTHWEST TENNESSEE...
...SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF3+), widespread severe/damaging wind gusts, and scattered large
to very large hail.
...Mid Mississippi Valley/Midwest into the Mid-South/Lower
Mississippi Valley...
Forecast scenario largely unchanged in that a very active
severe-weather/tornado day is expected regionally, especially into
late afternoon and this evening. Initially, a relatively long-lived
linear cluster of convection persists at late morning across
east-central/south-central Illinois, with additional initially
elevated storms on its eastern/southern periphery, moving from
eastern Illinois into Indiana, with severe hail and damaging winds
persisting as early day hazards.
Over time, air mass will continue to moisten and rapidly destabilize
along/south of the MCS-associated outflow from central Missouri into
south-central Illinois. A mid/upper-level trough will eject
northeastward from the northern/central Plains into the Midwest and
middle Mississippi Valley through the period. Low-level mass
response will encourage the primary surface low to consolidate
across Minnesota/Wisconsin by this evening, with a warm front
effectively delineated by the morning convection.
Strengthening west-southwesterly flow aloft associated with a 50-70
kt mid-level jet will overspread much of the warm sector by peak
heating, and a 35-45 kt south-southwesterly low-level jet will both
provide ample low-level and deep-layer shear to support supercells.
Initially discrete surface-based development appears likely to occur
into mid-afternoon across the mid Mississippi Valley/Mid-South ahead
of the surface cold front, and perhaps along weak low-level
confluence zones in the open warm sector including generally near
the confluence of the Mississippi/Ohio Rivers southward into the
Mid-South.
These supercells will exist in a very favorable environment for
tornadoes through the afternoon and evening, and multiple strong to
intense tornadoes (EF2/3+) appear likely, especially from parts of
Missouri into Illinois along/near the effective front. This strong
tornado potential will also likely extend farther south within the
warm sector into the Mid-South.
By early evening, convection will probably tend to consolidate into
clusters of supercells and then more linear segments with some
increase in damaging wind potential aside from large hail and a
continued multi-mode tornado risk tonight.
...ArkLaTex into Texas...
While storm coverage may trend lesser with southwest extent, the
potential for at least isolated intense storms will exist across the
region. Supercells capable of producing large to very large hail and
occasional damaging winds are expected. Increasing low-level
warm/moist advection tonight could foster additional robust
thunderstorms along the retreating dryline and eventually the
southward-moving cold front.
..Guyer/Weinman.. 04/27/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Mon Apr 27 2026
Valid 272000Z - 281200Z
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS
EAST/SOUTHEAST MISSOURI...SOUTHERN ILLINOIS...WESTERN KENTUCKY...AND
NORTHWEST TENNESSEE...
...SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF3+), widespread severe/damaging wind gusts, and scattered large
to very large hail.
...20z Update...
Only minor adjustments were made to extend the Marginal Risk back
into southeastern Kansas/northeastern Oklahoma to account for storms
initiating over the last hour.
The Moderate Risk remains unchanged with this update. The morning
MCS is now moving through eastern Illinois/southern Indiana. Further
west in Missouri and western Illinois, modifying remnant outflow
remains near the St. Louis Metro. Cumulus south of this boundary
across southeastern Missouri into southern Illinois, cumulus within
the warm sector is deepening. Increasing MLCAPE/steepening lapse
rates are nosing northward in southern central Missouri and
south-central Illinois.
Just to the west of the Mississippi River, radar shows occasional
attempts at initiation within the open warm sector. While the
details continue to evolve, it likely that a corridor of conditional
threat for strong-intense tornadoes will develop from the Missouri
Bootheel into southern Illinois/western Kentucky. Within this region
strong daytime heating has led to a volatile air mass, with moderate
to strong MLCAPE 2000-3000 J/kg and strong deep layer shear. VAD
profiles frm PAH (Paducah, KY) and LSX (St. Louis, MO) indicate a
rich SRH environment of around 200-300 m2/s2 in the 0-1 km layer. It
is likely that supercells capable of all hazards, including
strong-intense tornadoes, large to very large hail, and damaging
winds. Will develop across this region soon. See MCD571 for
additional information.
The conditional threat for strong tornadoes will extend as far south
as the Arklatex into portions of western Tennessee. Through time,
storm mode will shift to become linear with the southward moving
front, which will bring an increase into the evening of damaging
wind threat. Line embedded tornadoes, some of which may be strong,
will continue to be a threat into the evening.
..Thornton.. 04/27/2026
.PREV DISCUSSION... /ISSUED 1150 AM CDT Mon Apr 27 2026/
...Mid Mississippi Valley/Midwest into the Mid-South/Lower
Mississippi Valley...
Forecast scenario largely unchanged in that a very active
severe-weather/tornado day is expected regionally, especially into
late afternoon and this evening. Initially, a relatively long-lived
linear cluster of convection persists at late morning across
east-central/south-central Illinois, with additional initially
elevated storms on its eastern/southern periphery, moving from
eastern Illinois into Indiana, with severe hail and damaging winds
persisting as early day hazards.
Over time, air mass will continue to moisten and rapidly destabilize
along/south of the MCS-associated outflow from central Missouri into
south-central Illinois. A mid/upper-level trough will eject
northeastward from the northern/central Plains into the Midwest and
middle Mississippi Valley through the period. Low-level mass
response will encourage the primary surface low to consolidate
across Minnesota/Wisconsin by this evening, with a warm front
effectively delineated by the morning convection.
Strengthening west-southwesterly flow aloft associated with a 50-70
kt mid-level jet will overspread much of the warm sector by peak
heating, and a 35-45 kt south-southwesterly low-level jet will both
provide ample low-level and deep-layer shear to support supercells.
Initially discrete surface-based development appears likely to occur
into mid-afternoon across the mid Mississippi Valley/Mid-South ahead
of the surface cold front, and perhaps along weak low-level
confluence zones in the open warm sector including generally near
the confluence of the Mississippi/Ohio Rivers southward into the
Mid-South.
These supercells will exist in a very favorable environment for
tornadoes through the afternoon and evening, and multiple strong to
intense tornadoes (EF2/3+) appear likely, especially from parts of
Missouri into Illinois along/near the effective front. This strong
tornado potential will also likely extend farther south within the
warm sector into the Mid-South.
By early evening, convection will probably tend to consolidate into
clusters of supercells and then more linear segments with some
increase in damaging wind potential aside from large hail and a
continued multi-mode tornado risk tonight.
...ArkLaTex into Texas...
While storm coverage may trend lesser with southwest extent, the
potential for at least isolated intense storms will exist across the
region. Supercells capable of producing large to very large hail and
occasional damaging winds are expected. Increasing low-level
warm/moist advection tonight could foster additional robust
thunderstorms along the retreating dryline and eventually the
southward-moving cold front.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1244 PM CDT Mon Apr 27 2026
Valid 281200Z - 291200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR
NORTH-CENTRAL/NORTHEAST TEXAS...SOUTHEAST
OKLAHOMA...CENTRAL/SOUTHERN ARKANSAS...NORTHERN LOUISIANA...NORTHERN
MISSISSIPPI...
...SUMMARY...
Scattered strong to severe thunderstorm development is probable
across parts of the southeastern Great Plains through the lower
Mississippi and Tennessee Valleys Tuesday afternoon and evening.
Large to very large hail, swaths of damaging wind, and a few
tornadoes are possible.
...Southeastern Great Plains into the Tennessee Valley...
Within broad southwesterly flow aloft, a mid/upper-level shortwave
trough is forecast to move from the south-central Rockies toward the
mid MS Valley on Tuesday. Other low-amplitude vorticity maxima may
move from TX toward the TN Valley and Southeast, to the south of the
primary shortwave trough. These features will impinge upon a
reservoir of strong instability extending from the southern Plains
into the lower MS Valley, resulting in a potentially active severe
weather episode Tuesday afternoon into Tuesday night.
Elevated convection will likely be ongoing across parts of the
region Tuesday morning, which could pose a threat for large hail and
locally gusty winds, especially within the more favorable lapse
rate/buoyancy environment across the southern Plains into the
ArkLaTex. Strong diurnal destabilization will be possible by Tuesday
afternoon, to the east of a dryline across TX, and along and to the
warm side of an outflow-influenced front extending from southeast OK
toward the mid MS Valley. Evolution of storm development remains
uncertain, but initiation will be possible along the dryline/front
and any other outflow boundaries in place by afternoon.
Strong buoyancy (MLCAPE of 3000-4000 J/kg across TX, and 2000 J/kg
as far east as the ArkLaMiss) and favorable deep-layer shear will
support supercell development, with an attendant threat of very
large hail initially. Modestly enhanced low-level flow from east TX
into the ArkLaMiss will also support some tornado potential, with
some conditional risk of a strong tornado with any sustained
supercell. An increase in storm coverage should lead to development
of storm clusters and potentially an MCS that would spread eastward
into the evening, with one or more swaths of damaging wind possible.
Storms should eventually weaken late in the period as they encounter
weaker instability with eastward extent, but the severe threat could
persist through much of the night with any organized storm
structures.
..Dean.. 04/27/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Mon Apr 27 2026
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
ALLEGHENY PLATEAU TO THE MID ATLANTIC...AND ALSO FROM PARTS OF TEXAS
TO THE CENTRAL GULF COAST REGION...
...SUMMARY...
Strong to locally severe storms are possible across parts of the
Allegheny Plateau into Mid Atlantic, as well as from west-central
Texas to the central Gulf Coast, mainly Wednesday afternoon and
evening.
...West-central TX into the Southeast/Central Gulf Coast...
A substantial buoyancy reservoir is expected to persist from parts
of central/south TX toward the lower MS Valley on Wednesday. Due to
substantial early-week convection, considerable uncertainty remains
regarding the potential for an ongoing isolated severe threat in the
morning, and the location of the composite front/outflow and
potential redevelopment during the afternoon and evening.
With favorable instability and deep-layer shear, the environment
will be conditionally favorable for organized convection, including
potential for large hail and locally damaging wind. Large-scale
ascent is likely to be displaced north of the primary surface
boundary and strongest instability, so storm coverage remains
uncertain, but isolated supercells and/or small clusters will be
possible along/south of the front. An increase in severe
probabilities may eventually be needed across parts of this region,
depending on observational and guidance trends regarding boundary
placement and anticipated storm coverage.
...Allegheny Plateau to the Mid Atlantic...
A vigorous mid/upper-level shortwave trough is forecast to move from
the Midwest toward the Mid Atlantic on Wednesday. An attendant
surface low will move from the upper OH Valley toward the Delmarva
region, with trailing front extending southwestward into parts of
the Southeast, Carolinas, and Virginia by afternoon. The expectation
for substantial early-day cloudiness and precipitation continues to
result in uncertainty regarding potential for appreciable
destabilization during the afternoon. If sufficient destabilization
can occur, then favorable large-scale ascent and deep-layer shear
related to the approaching shortwave trough could support organized
storms, with a threat of damaging wind and possibly some hail.
Due to the lingering uncertainties regarding destabilization, a
broad Level 1/Marginal Risk is maintained with this outlook. An
eventual increase in severe probabilities will be possible for parts
of the region, depending on how the uncertainties are resolved.
..Dean.. 04/27/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Mon Apr 27 2026
Valid 281200Z - 291200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO AND
WESTERN TEXAS...
...Southern Plains...
Deep layer westerly flow under a mid-level jet over the Southwest
and Southern Plains aided by enhanced downslope drying is still
expected to promote a broad fire weather threat across much of NM,
south-central CO and west TX Tuesday. Widespread west to southwest
winds of around 15 mph coupled with RH falling to 10-20% amid dry
fuels will increase fire spread potential amid receptive fuels. More
intense wind belts of 20-25 mph aligning with RH reductions close to
10% will yield critical fire weather conditions across east-central
and southeastern NM into adjacent portions of TX. Minor adjustments
to Critical and surrounding Elevated Highlights were made given
latest forecast guidance.
...Upstate New York and Western Vermont...
Increasing low-level southerly flow ahead of surface trough and cold
front will evolve across the Northeast Tuesday. Mid and upper-level
cloud cover from convection across the Midwest/Ohio River Valley
today will overspread the region tonight into Tuesday. Despite the
cloud cover, tightening surface pressure gradients will support a
modest southerly wind of 10-15 mph, with localized/terrain enhanced
20 mph corridors likely. The stronger southerly winds along with RH
reductions of 25-35% (locally 20%) are expected by early afternoon.
These dry and breezy conditions will align with receptive fuels to
promote an enhanced fire weather concern across upstate NY and
western VT, where Elevated Highlights have been introduced.
..Williams.. 04/27/2026
.PREV DISCUSSION... /ISSUED 0146 AM CDT Mon Apr 27 2026/
...Synopsis...
Critical fire weather conditions will continue into Tuesday across
parts of eastern NM and western TX. Early-morning water-vapor
imagery depicts a low-amplitude upper wave over central CA. This
feature will quickly progress eastward into the Southwest over the
next 48 hours, which will result in surface pressure falls and
increasing westerly gradient winds across the southern High Plains
Tuesday afternoon.
Latest forecast consensus is that wind speeds will generally
increase into the 15-20 mph range for most of the region. Given an
antecedent dry air mass and several preceding days of dry/windy
conditions, fuels will remain stressed through Tuesday and should
support some degree of fire spread. Additionally, increasing
downslope flow will maintain dry conditions with RH minimums in the
10-20% range likely. Critical fire weather conditions appear most
probable in the lee of the more prominent southern Rockies mountain
ranges where terrain enhancement of flow under the upper jet will
promote sustained winds closer to 20-25 mph.
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0413 PM CDT Mon Apr 27 2026
Valid 291200Z - 051200Z
...Synopsis...
Upper-level troughing moves into the eastern U.S. for the latter
part of the week while a cold front a parent surface low shifts off
the Eastern Seaboard by Day 4/Thursday. Dry westerly flow south of
the advancing cold front should bring a fire weather threat to
portions of southern GA and northern FL on Day 3/Wednesday where
fuels remain dry, although some rainfall is expected to temporarily
alleviate fire weather concerns on Day 4/Thursday. Farther west, a
Pacific upper-level trough advances towards Baja CA midweek. Robust
mid-level flow ahead of this trough will bolster a downslope regime,
allowing for continued fire weather concerns across portions of the
Southwest on Day 3/Wednesday. Widespread wetting rains are expected
across much of the Southern Plains as the Pacific trough moves into
the Southwest on Day 5/Thursday. Most of the eastern U.S. is
expected to receive rainfall through the week, reducing overall fire
weather concerns, although remaining dry pockets and thus receptive
fuels could remain particularly across central and northern Plains
and portions of the Southeast.
...Day 3/Wednesday...
...Southwest...
Enhanced mid-level flow will continue over the Southwest region
while a surface lee trough develops across the southern High Plains.
A modified, post frontal air mass filtering into OK, TX and eastern
NM will limit fire weather concerns across the southern High Plains,
with dry and breezy conditions impacting areas mainly along and west
of the central NM mountain ranges. 40% critical probabilities were
introduced across much of central and western NM into far eastern
AZ.
...Southeast...
Increasing west/southwest winds of 10-15 mph, south of a surface
trough migrating into the upper OH River Valley, should evolve
across portions of the Southeast on Day 3/Wednesday. Delayed Gulf
moisture return amid an existing dry boundary layer should support
minimum RH reductions of 20-30% across portions of southern GA into
northern FL by Wednesday afternoon. Fuels remain quite receptive
with ongoing active fires in the region. The dry and breezy
conditions along with a receptive fuel environment should yield
enhanced fire weather threat across southern GA and northern FL,
where 40% critical probabilities have been added.
..Williams.. 04/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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