RSS Mesoscale Discussions from Storm Prediction Center
WW 524 SEVERE TSTM IL IN KY 280100Z - 280600Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 524
NWS Storm Prediction Center Norman OK
800 PM CDT Mon Jul 27 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast Illinois
Southwest Indiana
Western Kentucky
* Effective this Monday night and Tuesday morning from 800 PM
until 100 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated large hail events to 1.5 inches in diameter possible
A tornado or two possible
SUMMARY...A few severe thunderstorms will probably move southward
into the Watch area this evening. The stronger storms, including a
supercell or two, will pose a risk for severe gusts (60 to 75 mph),
isolated large hail, and perhaps a brief tornado.
The severe thunderstorm watch area is approximately along and 35
statute miles east and west of a line from 30 miles north of
Evansville IN to 15 miles southwest of Owensboro KY. 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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 521...WW 522...WW 523...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
35030.
...Smith
Read more
WW 523 SEVERE TSTM IN KY 272345Z - 280600Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 523
NWS Storm Prediction Center Norman OK
745 PM EDT Mon Jul 27 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southern Indiana
Central and Eastern Kentucky
* Effective this Monday night and Tuesday morning from 745 PM
until 200 AM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
SUMMARY...A couple of thunderstorm clusters will move south into the
Watch area this evening. The stronger thunderstorms will pose a
risk for strong to severe gusts capable of wind damage (55 to 70
mph). This activity will gradually diminish towards the early
overnight.
The severe thunderstorm watch area is approximately along and 40
statute miles north and south of a line from 65 miles west of
Louisville KY to 65 miles east of Lexington KY. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU3).
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 520...WW 521...WW 522...
AVIATION...A few severe thunderstorms with hail surface and aloft to
0.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
34030.
...Smith
Read more
WW 521 SEVERE TSTM IL IN 271840Z - 280100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 521
NWS Storm Prediction Center Norman OK
240 PM EDT Mon Jul 27 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
East Central Illinois
Central Indiana
* Effective this Monday afternoon and evening from 240 PM until
900 PM EDT.
* Primary threats include...
Widespread damaging winds and isolated significant gusts to 80
mph likely
Isolated very large hail events to 2 inches in diameter possible
A tornado or two possible
SUMMARY...An intensifying cluster of thunderstorms over northwest
Indiana will track southward this afternoon through a very moist and
unstable air mass. Severe wind gusts are expected along the leading
edge of the storms, along with some risk of large hail and a tornado
or two.
The severe thunderstorm watch area is approximately along and 70
statute miles east and west of a line from 15 miles north northeast
of Lafayette IN to 35 miles south of Bloomington IN. 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 519...WW 520...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
31035.
...Hart
Read more
WW 0524 Status Updates
STATUS FOR WATCH 0524 HAS NOT BEEN ISSUED YET
Read more
WW 0523 Status Updates
STATUS REPORT ON WW 523
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 N SDF TO
20 N SDF TO 40 WSW HTS.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1777
..SQUITIERI..07/28/26
ATTN...WFO...LMK...JKL...
STATUS REPORT FOR WS 523
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
INC025-037-043-061-117-123-175-280240-
IN
. INDIANA COUNTIES INCLUDED ARE
CRAWFORD DUBOIS FLOYD
HARRISON ORANGE PERRY
WASHINGTON
KYC005-011-017-021-027-029-045-049-065-067-073-079-091-093-111-
113-123-129-137-151-155-163-165-167-173-175-179-185-197-205-209-
211-215-229-237-239-280240-
KY
. KENTUCKY COUNTIES INCLUDED ARE
ANDERSON BATH BOURBON
BOYLE BRECKINRIDGE BULLITT
CASEY CLARK ESTILL
FAYETTE FRANKLIN GARRARD
HANCOCK HARDIN JEFFERSON
JESSAMINE LARUE LEE
Read more
WW 0522 Status Updates
PCO)
Read more
WW 0521 Status Updates
STATUS REPORT ON WW 521
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNE LAF
TO 15 WSW IND TO 50 WNW LUK.
..SQUITIERI..07/27/26
ATTN...WFO...ILX...IND...
STATUS REPORT FOR WS 521
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC019-023-029-033-035-041-045-079-101-159-183-280040-
IL
. ILLINOIS COUNTIES INCLUDED ARE
CHAMPAIGN CLARK COLES
CRAWFORD CUMBERLAND DOUGLAS
EDGAR JASPER LAWRENCE
RICHLAND VERMILION
INC005-013-021-027-031-045-055-071-079-081-083-093-101-105-107-
109-119-121-133-153-157-165-167-171-280040-
IN
. INDIANA COUNTIES INCLUDED ARE
BARTHOLOMEW BROWN CLAY
DAVIESS DECATUR FOUNTAIN
GREENE JACKSON JENNINGS
JOHNSON KNOX LAWRENCE
MARTIN MONROE MONTGOMERY
MORGAN OWEN PARKE
PUTNAM SULLIVAN TIPPECANOE
VERMILLION VIGO WARREN
Read more
WW 0520 Status Updates
STATUS REPORT ON WW 520
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NE MMO TO
25 S VPZ TO 15 NE LAF.
WW 520 WILL BE ALLOWED TO EXPIRE AT 280000Z.
..SQUITIERI..07/27/26
ATTN...WFO...LOT...IWX...GRR...MKX...
STATUS REPORT FOR WS 520
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC075-091-197-280000-
IL
. ILLINOIS COUNTIES INCLUDED ARE
IROQUOIS KANKAKEE WILL
INC007-073-111-280000-
IN
. INDIANA COUNTIES INCLUDED ARE
BENTON JASPER NEWTON
LMZ849-280000-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
PENTWATER TO MANISTEE MI
Read more
MD 1777 CONCERNING SEVERE THUNDERSTORM WATCH 523... FOR PORTIONS OF EXTREME SOUTHERN INDIANA INTO CENTRAL AND EASTERN KENTUCKY
Mesoscale Discussion 1777
NWS Storm Prediction Center Norman OK
0829 PM CDT Mon Jul 27 2026
Areas affected...portions of extreme southern Indiana into central
and eastern Kentucky
Concerning...Severe Thunderstorm Watch 523...
Valid 280129Z - 280230Z
The severe weather threat for Severe Thunderstorm Watch 523
continues.
SUMMARY...A few damaging gusts may still occur with the stronger
storms before nocturnal cooling begins to limit the severe threat.
DISCUSSION...A loosely organized MCS, with a recent history of
producing a few damaging gusts, continues to track southward. While
nocturnal cooling will begin to stabilize the boundary layer and
limit the efficiency of downward momentum transport, surface
temperatures remain in the low 80s F just ahead of the storms. As
such, a few more damaging gusts are possible, at least in the next
1-2 hours.
..Squitieri.. 07/28/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JKL...ILN...LMK...
LAT...LON 38188670 38478585 38518463 38338374 37938341 37598345
37438405 37418473 37458530 37568597 37698647 38188670
MOST PROBABLE PEAK WIND GUST...55-70 MPH
Read more
MD 1776 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF WESTERN/CENTRAL NE INTO NORTHWEST KS
Mesoscale Discussion 1776
NWS Storm Prediction Center Norman OK
0802 PM CDT Mon Jul 27 2026
Areas affected...Parts of western/central NE into northwest KS
Concerning...Severe potential...Watch unlikely
Valid 280102Z - 280230Z
Probability of Watch Issuance...20 percent
SUMMARY...Strong to severe gusts and isolated hail remain possible
through dusk.
DISCUSSION...Strong to locally severe storms are ongoing this
evening from west-central NE into northwest KS, in advance of a
low-amplitude midlevel shortwave trough moving across the central
High Plains. Very rich low-level moisture is in place across the
region, with the 0-1 km mean mixing ratio of 19.8 on the 00Z LBF
sounding very near an all-time record for the site (per SPC's
sounding climatology). This moisture is resulting in strong to
extreme buoyancy (MLCAPE of 3000-5000 J/kg), despite rather warm
temperatures aloft. Effective shear of 30-40 kt is sufficient for at
least modest storm organization, with organized multicells and
perhaps a supercell or two possible through dusk. Large PW and
relatively favorable lapse rates will continue to support strong to
locally severe gusts, and isolated hail cannot be ruled out with the
strongest cells.
..Dean/Smith.. 07/28/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...LBF...GLD...
LAT...LON 39240103 41520057 42780091 42970071 42980003 42729973
41279885 40069859 39449885 39189983 39150031 39130072
39240103
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 1775 CONCERNING SEVERE THUNDERSTORM WATCH 521... FOR PORTIONS OF FAR EASTERN ILLINOIS INTO WESTERN INDIANA AND FAR NORTHWESTERN KENTUCKY
Mesoscale Discussion 1775
NWS Storm Prediction Center Norman OK
0709 PM CDT Mon Jul 27 2026
Areas affected...portions of far eastern Illinois into western
Indiana and far northwestern Kentucky
Concerning...Severe Thunderstorm Watch 521...
Valid 280009Z - 280145Z
The severe weather threat for Severe Thunderstorm Watch 521
continues.
SUMMARY...The severe threat should continue for several more hours,
with damaging gusts the main threat. Given that Severe Thunderstorm
Watch 521 is set to expire at 01Z, a WW time extension or a new
Severe Thunderstorm Watch issuance will be needed to cover the
longer-term threat.
DISCUSSION...Supercells continue to track southward along the
western flank of a broader region of convection. MRMS mosaic MESH
radar data shows severe hail falling with these storms, several of
which containing 30 dBZ echo tops exceeding 50 kft. These storms
continue to track southward amid an airmass characterized by 4000
J/kg MLCAPE and 50-60 kts of effective bulk shear. Given the highly
favorable ambient parameter space preceding these storms, severe
potential should continue for at least a few more hours, which
exceeds the expiration time of Severe Thunderstorm Watch 521.
Therefore, either a temporal extension of Severe Thunderstorm Watch
521 or a new Severe Thunderstorm Watch issuance will likely be
needed in the next hour or so.
..Squitieri/Smith.. 07/28/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LMK...IND...PAH...LOT...ILX...
LAT...LON 37778793 40648786 40668755 40518712 40228676 40018665
39598665 39038681 38408692 37948693 37638703 37528718
37528756 37628779 37778793
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Mon Jul 27 2026
Valid 280100Z - 281200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY...
...SUMMARY...
Thunderstorms with severe wind gusts and hail are expected this
evening across parts of the Ohio Valley. Additional storms with
severe wind gusts are also expected from Lower Michigan southward
into Ohio. A few strong gusts will also be possible in parts of the
central Plains and in south-central Arizona.
...Ohio Valley/Great Lakes...
On water vapor imagery, a mid-level shortwave trough is moving
southward through the Ohio Valley. Ahead of this feature, a moist
and unstable airmass is in place with surface dewpoints in the 70s
and low 80s F. The RAP has a pocket of strong instability located
from western Kentucky into southern Indiana, where MLCAPE is
estimated in the 3500 to 4500 J/kg range. Scattered strong to severe
storms are ongoing along the northern edge of the stronger
instability, and the storms are being supported by large-scale
ascent associated with the shortwave trough. In addition, the
WSR-88D VWP at Louisville has 0-6 km shear of 30 to 35 knots
suggesting a potential for organized severe storms will continue
this evening. Severe wind gusts will be possible with supercells and
short bowing line segments. The greatest coverage of severe is
expected to be over southern Indiana and far northern Kentucky...see
MCD 1774.
Further north into Lower Michigan, scattered strong thunderstorms
are ongoing ahead a subtle shortwave trough evident on water vapor
imagery. Short-term model forecasts suggest these storms will expand
in coverage and move southward across Lower Michigan into Ohio
during the late evening and early overnight period. Along this
corridor, the RAP has MLCAPE in the 1000 to 1500 J/kg range with 40
to 50 knot of deep-layer shear. This should support a wind-damage
threat with organized short line segments.
...Central Plains...
At mid-levels, a subtle shortwave trough is currently moving over
the top of a ridge in the central High Plains. Ahead of the
shortwave trough, scattered strong thunderstorms are ongoing along
the western edge of a pocket of strong instability. The RAP
currently shows MLCAPE over central Nebraska in the 4000 to 5500
range. Even though forecast soundings near the instability maximum
have low to mid-level wind speeds generally less than 20 knots, the
instability combined with very steep low-level lapse rates may be
enough for isolated severe wind gusts for a few more hours this
evening.
...Arizona...
The latest surface analysis shows a sufficiently moist airmass in
place over the southern half of Arizona, where dewpoints are mostly
in the mid to upper 50s F. Within the moist air, the RAP has a
pocket of moderate instability with MLCAPE in the 1500 to 2500 J/kg
range. Thunderstorm have developed along the northern edge of the
stronger instability. These storms will move westward across
south-central Arizona this evening, and may pose a threat for severe
wind gusts due to very steep low to mid-level lapse rates...MCD
1772.
..Broyles.. 07/28/2026
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0438 PM CDT Mon Jul 27 2026
Valid 291200Z - 041200Z
...Synopsis...
Upper-level troughing is forecast across portions of the Pacific
Northwest through much of the workweek, with the main upper-level
low remaining offshore. Meanwhile, periodic mid-level shortwaves
will rotate through the base of the trough and over the area within
the southwest flow aloft. The strongest and most well-defined
shortwave is forecast Day 4/Thursday, potentially allowing a
thunderstorm threat to emerge. Thereafter, longer-range ensemble
guidance continues to suggest that the aforementioned upper-level
low may move onshore this weekend, yielding dry and breezy
conditions across the Northwest and Northern Rockies; though timing
details remain uncertain.
...Northwestern US...
Weaker flow aloft will limit a broader fire weather threat across
the Pacific Northwest through much of the week. Though, locally
elevated fire weather conditions appear likely most days due to
lingering dry and breezy conditions amid receptive fuels. Dry
thunderstorm chances may return on Day 4/Thursday as the
aforementioned shortwave trough impinges upon the region amid ample
instability, a dry boundary layer, and sufficient mid-level
moisture, supporting the introduction of 10% probabilities. A
persisting dry airmass and warm daytime temperatures are expected to
increase fuel receptivity, enhancing concerns for new lightning
ignitions. Longer range guidance continues to suggest dry and breezy
conditions should return to the Northwest sometime this weekend as
the offshore trough moves inland. As such, 40% Critical
probabilities have been introduced on Days 6-7/Saturday-Sunday where
ensemble RH/wind joint probabilities highlight increased
probabilities to overlap exceptionally dry fuels. The spatial extent
of drawn probabilities may be adjusted in future outlook cycles as
predictability increases.
...Southern High Plains...
Hot, dry, and breezy conditions are likely across portions of the
southern High Plains through much of the workweek; however, recent
fuel guidance suggests the fuelscape remains mostly mixed and winds
are forecast to generally remain at or below elevated thresholds.
Nevertheless, fuels are expected to continue drying due to the
multiple days of hot, dry, and breezy conditions, which may
necessitate fire weather highlights in later forecasts.
..Elizalde-Garcia.. 07/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
|
