RSS Mesoscale Discussions from Storm Prediction Center
WW 459 SEVERE TSTM DE MD NJ NY PA CW 041930Z - 050300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 459
NWS Storm Prediction Center Norman OK
330 PM EDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Delaware
Eastern Maryland
New Jersey
Central and Southeast New York
Central and Eastern Pennsylvania
Coastal Waters
* Effective this Saturday afternoon and evening from 330 PM until
1100 PM EDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated large hail events to 1 inch in diameter possible
SUMMARY...Thunderstorms will increase in coverage through the
afternoon across the watch area, in a warm and unstable air mass.
Locally damaging wind gusts and some hail are likely with the more
intense cores.
The severe thunderstorm watch area is approximately along and 95
statute miles north and south of a line from 25 miles southwest of
Dubois PA to 35 miles southeast of Monticello NY. 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 454...WW 455...WW
456...WW 457...WW 458...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
28030.
...Hart
Read more
WW 458 SEVERE TSTM TX 041850Z - 050200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 458
NWS Storm Prediction Center Norman OK
150 PM CDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Texas Panhandle
* Effective this Saturday afternoon and evening from 150 PM until
900 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1 inch in diameter possible
SUMMARY...Thunderstorms will continue to develop in a hot and
unstable air mass. The strongest cells through the early evening
will pose a risk of damaging winds.
The severe thunderstorm watch area is approximately along and 40
statute miles north and south of a line from 100 miles southwest of
Amarillo TX to 100 miles east northeast of Amarillo TX. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU8).
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 454...WW 455...WW
456...WW 457...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
27020.
...Hart
Read more
WW 457 SEVERE TSTM DC MD VA WV CW 041815Z - 050200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 457
NWS Storm Prediction Center Norman OK
215 PM EDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
District Of Columbia
Maryland
Virginia
Eastern West Virginia
Coastal Waters
* Effective this Saturday afternoon and evening from 215 PM until
1000 PM EDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated large hail events to 1 inch in diameter possible
SUMMARY...Numerous thunderstorms will develop and spread across the
watch area through the afternoon and early evening, in and hot and
humid air mass. Damaging wind gusts are likely with the strongest
storm clusters.
The severe thunderstorm watch area is approximately along and 110
statute miles east and west of a line from 35 miles northeast of
Martinsburg WV to 55 miles south southeast of Roanoke VA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU7).
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 454...WW 455...WW 456...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
25030.
...Hart
Read more
WW 456 SEVERE TSTM OH PA WV 041800Z - 050100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 456
NWS Storm Prediction Center Norman OK
200 PM EDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and Eastern Ohio
Western Pennsylvania
Northern West Virginia
* Effective this Saturday afternoon and evening from 200 PM until
900 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
SUMMARY...Thunderstorms will develop across the watch area and
spread southeastward through the afternoon. Locally damaging wind
gusts may accompany the stronger storms.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 45 miles west of
Columbus OH to 15 miles north of Dubois PA. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU6).
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 454...WW 455...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.
...Hart
Read more
WW 455 SEVERE TSTM IL IN LM 041735Z - 050000Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 455
NWS Storm Prediction Center Norman OK
1235 PM CDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northern Illinois
Northwest Indiana
Lake Michigan
* Effective this Saturday afternoon and evening from 1235 PM
until 700 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
SUMMARY...Thunderstorms will develop across the watch area through
the afternoon in a relatively hot and humid air mass. The strongest
cells will pose a risk of locally damaging wind gusts.
The severe thunderstorm watch area is approximately along and 75
statute miles north and south of a line from 45 miles northwest of
Bloomington IL to 45 miles north northeast of Danville IL. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).
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 454...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.
...Hart
Read more
WW 454 SEVERE TSTM MO 041720Z - 050000Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 454
NWS Storm Prediction Center Norman OK
1220 PM CDT Sat Jul 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Western and Central Missouri
* Effective this Saturday afternoon and evening from 1220 PM
until 700 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...A cluster of thunderstorms will track eastward across the
watch area through the afternoon, posing a risk of locally damaging
wind gusts.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 65 miles southwest of
Knob Noster MO to 25 miles south of Jefferson City MO. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU4).
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.
&&
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
27030.
...Hart
Read more
WW 0459 Status Updates
STATUS FOR WATCH 0459 HAS NOT BEEN ISSUED YET
Read more
WW 0458 Status Updates
STATUS REPORT ON WW 458
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..JEWELL..07/04/26
ATTN...WFO...AMA...LUB...
STATUS REPORT FOR WS 458
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC011-017-045-065-069-117-129-153-179-189-191-211-233-279-295-
369-375-381-393-437-483-042140-
TX
. TEXAS COUNTIES INCLUDED ARE
ARMSTRONG BAILEY BRISCOE
CARSON CASTRO DEAF SMITH
DONLEY FLOYD GRAY
HALE HALL HEMPHILL
HUTCHINSON LAMB LIPSCOMB
PARMER POTTER RANDALL
ROBERTS SWISHER WHEELER
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.
Read more
WW 0457 Status Updates
STATUS FOR WATCH 0457 HAS NOT BEEN ISSUED YET
Read more
WW 0456 Status Updates
STATUS FOR WATCH 0456 HAS NOT BEEN ISSUED YET
Read more
WW 0455 Status Updates
STATUS REPORT ON WW 455
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SW PIA TO
35 N PIA TO 25 NNW MMO TO 30 ESE RFD.
..JEWELL..07/04/26
ATTN...WFO...DVN...ILX...LOT...IND...
STATUS REPORT FOR WS 455
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC011-019-029-031-039-041-043-045-053-063-075-089-091-093-099-
105-107-113-115-123-139-143-147-155-175-179-183-197-203-
042040-
IL
. ILLINOIS COUNTIES INCLUDED ARE
BUREAU CHAMPAIGN COLES
COOK DE WITT DOUGLAS
DUPAGE EDGAR FORD
GRUNDY IROQUOIS KANE
KANKAKEE KENDALL LA SALLE
LIVINGSTON LOGAN MCLEAN
MACON MARSHALL MOULTRIE
PEORIA PIATT PUTNAM
STARK TAZEWELL VERMILION
WILL WOODFORD
INC007-045-073-089-111-121-127-165-171-042040-
IN
. INDIANA COUNTIES INCLUDED ARE
BENTON FOUNTAIN JASPER
Read more
WW 0454 Status Updates
STATUS REPORT ON WW 454
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SW TBN TO
5 ESE TBN TO 10 W VIH TO JEF TO 40 N COU.
..JEWELL..07/04/26
ATTN...WFO...EAX...SGF...LSX...
STATUS REPORT FOR WS 454
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC119-133-157-163-042140-
IL
. ILLINOIS COUNTIES INCLUDED ARE
MADISON MONROE RANDOLPH
ST. CLAIR
MOC027-055-071-073-099-125-139-151-161-169-183-186-187-189-219-
221-510-042140-
MO
. MISSOURI COUNTIES INCLUDED ARE
CALLAWAY CRAWFORD FRANKLIN
GASCONADE JEFFERSON MARIES
MONTGOMERY OSAGE PHELPS
PULASKI ST. CHARLES STE. GENEVIEVE
ST. FRANCOIS ST. LOUIS WARREN
WASHINGTON
MISSOURI INDEPENDENT CITIES INCLUDED ARE
Read more
MD 1498 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF NORTHEASTERN COLORADO INTO WESTERN AND CENTRAL NEBRASKA
Mesoscale Discussion 1498
NWS Storm Prediction Center Norman OK
0413 PM CDT Sat Jul 04 2026
Areas affected...portions of northeastern Colorado into western and
central Nebraska
Concerning...Severe potential...Watch possible
Valid 042113Z - 042215Z
Probability of Watch Issuance...60 percent
SUMMARY...Multiple instances of severe wind and hail will accompany
the stronger and longer lasting storms, especially during their
mature stage. A WW issuance may be needed pending greater storm
coverage.
DISCUSSION...Multiple multicells and transient supercells have
developed over the past couple of hours, with an instance of 2+ inch
diameter hail recently reported in Keith County, NE. These storms
are developing along a diffuse baroclinic boundary aligned from
western NE into far northeastern CO, amid appreciable buoyancy
(1500-3000 J/kg MLCAPE), but relatively poor vertical wind shear.
Given the current shear profile, it is unclear how widespread and
long-lasting any severe threat will be. Nonetheless, 8+ C/km
mid-level lapse rates overspreading the central High Plains, where
storms are already present, suggests that a severe threat may
persist through the afternoon/evening. As such, a WW issuance is
possible if storms increase in coverage.
..Squitieri/Gleason.. 07/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...GLD...BOU...CYS...
LAT...LON 40990497 41230415 41280353 41410294 41910236 42360170
42710099 42710034 42380001 41979994 41410016 40870066
40470142 40210215 40120292 40080351 40060410 40250461
40990497
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
MD 1497 CONCERNING SEVERE THUNDERSTORM WATCH 455... FOR NORTHEAST ILLINOIS INTO WESTERN INDIANA
Mesoscale Discussion 1497
NWS Storm Prediction Center Norman OK
0351 PM CDT Sat Jul 04 2026
Areas affected...northeast Illinois into western Indiana
Concerning...Severe Thunderstorm Watch 455...
Valid 042051Z - 042215Z
The severe weather threat for Severe Thunderstorm Watch 455
continues.
SUMMARY...Locally damaging wind gusts remain possible from
east-central Illinois into western Indiana. A new watch may not be
needed depending on trends.
DISCUSSION...Convection increased ahead of the MCV moving out of IA,
but has generally moved slowly, producing heavy rain. The air mass
across the region continues to heat and destabilize, and remains
sufficient for at least localized severe wind gusts. Recent radar
trends have shown some bowing storms, which may be capable of
damaging gusts. Unless storms become better organized, an additional
watch may not be needed downstream.
..Jewell.. 07/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...IWX...IND...LOT...ILX...
LAT...LON 39958946 40708881 41388845 41738846 42038821 42078797
41698681 41108659 40168670 39828687 39528762 39428837
39718924 39958946
MOST PROBABLE PEAK WIND GUST...55-70 MPH
Read more
MD 1496 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PARTS OF SOUTHERN KANSAS AND NORTHERN OKLAHOMA
Mesoscale Discussion 1496
NWS Storm Prediction Center Norman OK
0349 PM CDT Sat Jul 04 2026
Areas affected...Parts of southern Kansas and northern Oklahoma
Concerning...Severe potential...Watch likely
Valid 042049Z - 042315Z
Probability of Watch Issuance...95 percent
SUMMARY...Severe thunderstorm development is expected between
22-00Z. The primary concerns will be severe wind gusts and large
hail.
DISCUSSION...The latest visible satellite imagery depicts an
increasingly agitated boundary-layer cumulus field evolving at the
nose of a robust heat axis extending into northwest OK. Additional
deepening cumulus is evident along a remnant outflow boundary in
south-central KS into northern OK. Over the next few hours,
continued diurnal heating should promote thunderstorm development in
these zones of mesoscale ascent.
The pre-convective environment is characterized by a warm/moist PBL
(lower 70s dewpoints) beneath steep midlevel lapse rates (sampled by
the DDC 18Z sounding). The resultant strong surface-based buoyancy
and around 40 kt of effective shear (with modest low-level hodograph
curvature) will initially promote semi-discrete supercells capable
of producing severe wind gusts and very large hail. While uncertain,
a tornado cannot be entirely ruled out with any boundary/storm
interactions. With time, increasing storm coverage and congealing
cold pools should promote upscale growth into organized clusters,
with an increasing risk for scattered severe/damaging gusts with
southward extent. A watch is likely this afternoon.
..Weinman/Hart.. 07/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TSA...ICT...OUN...DDC...
LAT...LON 35909567 35739628 35659703 35709801 35909890 36279943
36699957 36979945 37219919 37459835 37679589 37539539
37229511 36639504 36209520 35909567
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
MD 1495 CONCERNING SEVERE THUNDERSTORM WATCH 454... FOR CENTRAL INTO EASTERN MISSOURI AND FAR WEST-CENTRAL ILLINOIS
Mesoscale Discussion 1495
NWS Storm Prediction Center Norman OK
0236 PM CDT Sat Jul 04 2026
Areas affected...central into eastern Missouri and far west-central
Illinois
Concerning...Severe Thunderstorm Watch 454...
Valid 041936Z - 042130Z
The severe weather threat for Severe Thunderstorm Watch 454
continues.
SUMMARY...A small but long-lived storm/bow may continue to produce
damaging winds from central Missouri toward the St. Louis vicinity
this afternoon.
DISCUSSION...An eastward-moving storm complex persists this
afternoon, producing areas of wind damage from west-central into
central MO. This bow is now moving along a confluence zone which can
be seen in surface obs and also by virtue of an east-west corridor
of enhanced CU and isolated leading convection. The environment
remains quite unstable from MO into southern IL, and daytime heating
continues. The bow has fluctuated in intensity at times, as outflow
pushes ahead of the system. However, portions of this system may
regenerate and continue to produce periodic wind damage as the
outflow surge continues east.
..Jewell.. 07/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LSX...SGF...EAX...
LAT...LON 37849095 37959289 38289272 38759299 39059039 38908985
38618967 38068976 37909002 37849095
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 1494 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF SOUTHERN NY...NORTH-CENTRAL/NORTHEAST PA...AND NORTHERN NJ
Mesoscale Discussion 1494
NWS Storm Prediction Center Norman OK
0205 PM CDT Sat Jul 04 2026
Areas affected...Portions of southern NY...north-central/northeast
PA...and northern NJ
Concerning...Severe potential...Watch likely
Valid 041905Z - 042130Z
Probability of Watch Issuance...80 percent
SUMMARY...The area is being monitored for an increasing risk of
severe thunderstorms this afternoon. The primary concern is damaging
wind gusts. A watch is likely.
DISCUSSION...The latest visible satellite imagery indicates an
east/west-oriented band of deepening boundary-layer cumulus across
northern PA -- within a zone of broadly confluent low-level flow.
Thunderstorms should continue increasing in coverage and intensity
within this zone over the next few hours, given ample diurnal
heating/destabilization of a moist air mass (upper 60s to lower 70s
dewpoints). Steepening low-level lapse rates and around 30-40 kt of
unidirectional shear should promote several organized clusters
capable of producing scattered damaging wind gusts through the
afternoon. An additional focus for severe thunderstorms is evident
downstream of Lake Ontario, where an MCV and related thunderstorms
will continue eastward into the diurnally destabilizing air mass.
These storms will also pose a risk of damaging wind gusts as they
intercept the unstable air.
..Weinman/Hart.. 07/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 42977639 42777539 42467446 42187406 41587395 40947431
40367544 40567693 40847778 41257819 41787840 42167828
42557787 42847717 42977639
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0248 PM CDT Sat Jul 04 2026
Valid 042000Z - 051200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE SOUTHERN PLAINS AND MID ATLANTIC...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE CENTRAL HIGH PLAINS AND FROM THE SOUTHERN HIGH PLAINS TO
SOUTHERN NEW ENGLAND...
...SUMMARY...
Clusters of storms will continue to move across parts of the
Allegheny Plateau into the Mid-Atlantic, with potential for numerous
damaging wind gusts. Additional severe thunderstorms are still
expected across the Great Plains this afternoon and evening, posing
a risk for severe wind gusts and large hail.
...20Z Update...
A cold-pool-driven MCS, with a history of measured 50+ kt gusts and
wind damage, continues to rapidly propagate eastward across central
MO. While deep-layer shear is quite modest over the Ozarks, a
pronounced baroclinic boundary is draped across central MO into the
St. Louis Metropolitan area. The MCS has likely maintained its
intensity thus far by riding this boundary and ingesting some
vorticity for bookend vortex and rear-inflow jet maintenance. It is
unclear how long this MCS will remain strong/organized given the
lack of ambient deep-layer shear. However. surface temperatures on
the warm side of the boundary exceeding 90 F, amid mid 70s F
dewpoints, is yielding a gradient of 2500-4500 J/kg SBCAPE, which
should support some severe gust threat for this MCS for at least the
next few hours. As such, 30 percent wind probabilities have been
added ahead of the MCS.
Guidance consensus, including early depictions from WoFS output,
suggests that an MCS will quickly surge southeastward across
portions of the southern Plains after initiating along the KS/OK
border late this afternoon. The farther southeast initiation (given
the current position of the surface outflow boundary left behind
from the previous MCS), and southeastward surging potential, it
appears that the greatest wind threat will exist into east-central
OK. 30 percent/CIG1 wind probabilities have been extended into this
region.
Five percent hail probabilities have been added across portions of
the lower Hudson Valley. Here, MRMS mosaic MESH data suggests that
marginally severe hail may already be falling with the more robust
storms over northern PA. Furthermore, stronger mid-level flow is
grazing the lower Hudson Valley, contributing to 30-40 kts of
effective bulk shear amid 1000+ J/kg MLCAPE, which should be
adequate to support a continued hail threat.
Otherwise, the previous forecast remains on track, including the
potential for numerous damaging to occasionally severe gusts
expected across portions of the Mid Atlantic into southern New
England through the afternoon and evening hours. Mostly minor
adjustments have been made to the remainder of the outlook to
account for guidance consensus and observations.
..Squitieri.. 07/04/2026
.PREV DISCUSSION... /ISSUED 1101 AM CDT Sat Jul 04 2026/
...Mid Atlantic...
A hot summer day is forecast across the Mid Atlantic region today
with temperatures well into the 90s and dewpoints ranging from the
mid 60-lower 70s F. Full sun will result in steep low-level lapse
rates and high CAPE values beneath moderately strong northwest
mid-level flow. Scattered thunderstorms are expected to develop
along/east of the Blue Ridge and spread eastward across parts of
PA/VA/NJ/DE through the late afternoon and evening. Parameters
remain favorable for downburst winds in these clusters of storms.
...PA/NY into southern New England...
A weak shortwave trough and associated mid level speed max is
rotating southeastward out of Ontario/Quebec into the northeast US.
Ample low-level moisture and pockets of moderate CAPE will result in
widely scattered afternoon thunderstorm development from northern PA
into central NY. These storms will spread southeastward into
southern New England by early evening. The strongest cells will
pose a risk of damaging wind gusts.
..IL/IN...
A remnant MCV from overnight convection is analyzed over eastern IA,
with a surface boundary extending eastward just south of CHI. The
air mass to the south of the boundary across IL will become very
unstable by mid-afternoon, leading to scattered thunderstorms.
Favorable thermodynamic parameters suggest a risk of damaging winds
as these storms organize and track into IN by evening.
...KS/MO...
An ongoing cluster of strong/severe storms is affecting eastern KS.
Given the moist and unstable air mass to the east and sufficient
mesoscale organization, it is probable that this cluster will
persist into the afternoon. Storms will track into western MO with
a continued risk of locally damaging wind gusts.
...KS/OK/AR...
In the wake of the aforementioned cluster of storms, new development
is likely later this afternoon along the remnant outflow boundary
across southern KS and northern OK. High CAPE values to the south
of the boundary will promote the ENH risk of damaging winds and some
hail as storms build southeastward across central/eastern OK and
into western AR this evening.
...TX Panhandle...
A weak surface boundary will be the focus for scattered late
afternoon thunderstorms over the southern/eastern TX Panhandle. The
strongest cells may produce damaging wind gusts and large hail for a
few hours.
...Northeast CO...
Southerly low level winds will maintain dewpoints in at least the
40s over parts of eastern CO this afternoon despite strong
heating/mixing. This will be sufficient to allow scattered
thunderstorms to form along the foothills and DCVZ. A few severe
cells are possible with large hail being the main risk.
...MN/SD...
Similar to yesterday, a few afternoon and early evening
thunderstorms are expected to develop ahead of a weak shortwave
trough. The strongest cells might produce large hail or gusty
winds.
Read more
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1203 PM CDT Sat Jul 04 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
MID-ATLANTIC SUNDAY AFTERNOON AND EVENING...
...SUMMARY...
Scattered wind damage is possible with thunderstorms across the
Mid-Atlantic Sunday afternoon and evening. Isolated strong storms
also are possible across Montana and western North Dakota, and
portions of the southern Plains to the Tennessee Valley.
...Mid-Atlantic...
A weak surface low is forecast to move west to east along a sagging
cold front/baroclinic zone draped across PA into northern
NJ/southeast NY on Sunday/Sunday evening. Meanwhile, lee troughing
will develop across VA. A hot and very moist airmass will reside
near and south of these boundaries, which will serve as a focus for
severe storm development during the afternoon and into evening.
Southwesterly flow aloft will weaken through the day as an upper
shortwave impulse lifts northeast of the region, but around 20-30 kt
mid/upper-level flow will persist. Moderate to strong
destabilization is expected and thunderstorm clusters are expected
by early to mid-afternoon. Sufficient clustering could occur along
the southward-sagging cold front and one or more forward propagating
clusters will be possible from northern VA into southeast PA until
storms move offshore the Mid-Atlantic coast during the evening.
Sufficient consistency among deterministic/CAMs and AI/ML guidance
exists regarding storm coverage to warrant an upgrade to 30 percent
wind probabilities for portions of the region.
...Southern Plains to TN Valley...
An remnant/weakening MCS is expected to be located over OK or AR
Sunday morning. An MCV related to this feature will progress
eastward toward the Lower MS and TN Valley vicinity through the day.
Further south and west near the Red River Valley/North Texas into
the southern High Plains, outflow associated with the late-Day
1/Saturday into early Day 2/Sunday MCS may arc across this region.
Differential heating could occur along this boundary, providing
support for redevelopment during the afternoon/evening. Boundary
layer moisture will be modest with westward extent into the High
Plains, but steep lapse rates aloft, and increasing moisture with
eastward extent into the Lower MS Valley will support a corridor of
moderate instability in the vicinity of the surface boundary.
Northwesterly flow aloft will also modestly strengthen through the
day, fostering weak, but perhaps sufficient vertical shear for
transient organized cells/clusters along the boundary.
Further east, the MCV will locally enhance vertical shear amid a
very moist and moderately unstable airmass. This could foster
potential for one or more forward propagating storm clusters, and
some risk for damaging gusts from wet microbursts, leading to a
broad expansion of the Marginal (level 1 of 5) risk across parts of
the Lower MS/TN Valley vicinity.
...Northern Rockies into North Dakota...
West/southwest flow aloft will strengthen across MT into ND as an
upper shortwave trough moving across western Canada glances northern
portions of the U.S. A plume of steep midlevel lapse rates will
stretch from the northern Great Basin through southern/eastern MT
into the western Dakotas. Low-level moisture will not be impressive,
but the steep lapse rates aloft will support a corridor of modest
destabilization across MT, and somewhat greater across western ND
where boundary-layer moisture will be marginally better along a
surface trough. Vertically veering wind profiles, with increasing
speeds above 700 mb will support effective shear magnitudes greater
than 30 kt, and organized storms are possible. Strong gusts and
isolated hail will be the main hazards with these storms during the
afternoon into evening.
..Leitman.. 07/04/2026
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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0155 PM CDT Sat Jul 04 2026
Valid 061200Z - 071200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS INTO MINNESOTA...AND THE SOUTHERN
MID-ATLANTIC...
...SUMMARY...
Strong to severe thunderstorms are possible Monday afternoon and
evening across portions of the southern Mid-Atlantic and the
northern Plains.
...VA/NC vicinity...
Upper troughing over the Midwest will continue to slowly shift east
toward the Appalachians on Monday. Modest deep-layer southwesterly
flow will overspread the central Appalachians to the Mid-Atlantic
vicinity as a surface low develops in the vicinity of WV. A surface
boundary/cold front will sag southward across PA while surface
troughing develops in the lee of the VA/NC mountains. A very moist
airmass will persist and moderate destabilization is forecast.
Thunderstorm clusters will once again develop and pose a risk for
sporadic wind damage Monday afternoon into early evening.
...Northern Plains into northwest MN...
An upper shortwave trough will move east across the Canadian
Prairies, glancing the U.S. northern Plains vicinity. This will
bring a band of enhance mid/upper westerly flow across the region
while a surface cold front develops southeast through the afternoon
and nighttime hours. Southerly low-level flow will transport 60s
dewpoints northward ahead of the front beneath modestly steep
midlevel lapse rates. This will support moderate to strong
destabilization. It is uncertain how far south convection may
develop as large-scale ascent weakens into South Dakota and capping
increases. However, supercell wind profiles are evident in forecast
soundings, and where storms do develop, an accompanying risk for
severe gusts and large hail is possible. An upgrade to Slight risk
(level 2 of 5) may be needed in subsequent outlooks if confidence in
storm coverage increases.
..Leitman.. 07/04/2026
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0203 PM CDT Sat Jul 04 2026
Valid 051200Z - 061200Z
The IsoDryT area was expanded across portions of northeast
California, northwest Nevada, and into southwest Idaho. An
upper-level shortwave trough, currently off the coast of southern
California, is forecast to track northward across California and
into the northwest Great Basin over the next 36 hours. This will
bring moisture and forcing for ascent aloft, which will help develop
isolated to scattered mixed wet/dry thunderstorms across portions of
northern California, northwest Nevada, southern/eastern Oregon, and
southwest Idaho. High-based shallow convective showers will track
north across central/northern California and northwest Nevada during
the day, with thunderstorm development likely starting in the
afternoon and continuing through the evening and possibly overnight.
ERCs are generally below average for this time of year, but field
reports indicate increasing fuel receptiveness and initial attack.
Isolated to perhaps scattered mixed wet/dry thunderstorms are
possible across portions of central/southern Colorado, most likely
along and east of the southern Front Range and Sangre de Cristo
Mountains. There is potential for thunderstorms to develop west of
the Sangre de Cristo Mountains and along the eastern San Juans into
the Sawatch Range. An IsoDryT area was not introduced given the
potential limited corridor of drier storms and uncertainty regarding
development and coverage. However, any storm that does develop west
of the I-25 corridor, will be over near to record dry fuels.
Additionally, deep pyroconvection over active large wildfires in the
vicinity of this area is possible.
..Nauslar.. 07/04/2026
.PREV DISCUSSION... /ISSUED 0144 AM CDT Sat Jul 04 2026/
...Synopsis...
Fire weather concerns will primarily be driven by dry thunderstorm
potential on Sunday. While confidence in dry thunderstorms is
greatest across portions of the Pacific Northwest, more isolated
concerns may emerge across eastern Arizona into southwest New
Mexico.
...Pacific Northwest...
Upper-level ridging will continue to build across the Southwest/Four
Corners region through the weekend. Guidance continues to show
fairly good agreement in the northward propagation of a shortwave
trough across northern CA into southern OR on the western periphery
of the upper ridge through the day. A subtle influx of Pacific
moisture ahead of the wave coupled with mid-level ascent/cooling
will likely support isolated thunderstorms from northern CA into
southeast OR and perhaps far northwest NV. Slow storm motions may
allow for pockets of wetting rainfall, but fairly dry low-level
conditions and PWAT values between 0.5 to 0.75 inches will support
dry lightning strikes, especially away from the heavier cores. Based
on information from local offices, fuels across the region are
generally receptive and should support lightning ignitions. Dry
thunderstorm highlights were introduced to address this concern.
...Eastern Arizona/Southwest New Mexico...
A modest influx of mid-level moisture from the Gulf of California
into eastern AZ/western NM is anticipated through the day Sunday.
Some recent model solutions hint that this moisture will provide
sufficient buoyancy for very weak convection by late afternoon when
boundary-layer mixing will be maximized. Very weak forcing for
ascent under the upper ridge suggests that any thunderstorm
potential will most likely be tied to orographic ascent along the
eastern Mogollon Rim and within the Gila region. While confidence in
thunderstorm development is limited based on the synoptic regime and
somewhat limited signal in CAM guidance, the potential for dry
thunderstorms over a receptive fuel landscape is highlighted.
...Please see www.spc.noaa.gov/fire for graphic product...
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