Alert archive / Missouri / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 20, NWS St. Louis, MO

April 7, 2015Franklin County, Jefferson County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 7, 2015, 9:18 AM CDT for Franklin County, Jefferson County, Missouri. It was in force for 42 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 7, 2015, 9:18 AM CDT (14:18 UTC)
Expired: Apr 7, 2015, 10:00 AM CDT
In force: 42 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.25 in
Wind: 50.0 mph

Counties Franklin County, MO, Jefferson County, MO

The radar

The St Louis radar (KLSX), 32 km from the middle of the area, began a volume at 14:17 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Apr 7, 9:45 AM CDT	HAIL 1	5 Ne St. Clair, MO	ON I44 NEAR MM245
Apr 7, 9:55 AM CDT	HAIL 2	4 E St. Clair, MO	DAMAGE TO CAR HOOD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 2 storm reports to this severe thunderstorm warning; the first came 27 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 7, 8:34 AM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 2.3 hours before the alert went out and 268 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 134 J/kg
Mixed-layer CIN: -199 J/kg
Mixed-layer LCL: 443 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 87 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

171 
WUUS53 KLSX 071418
SVRLSX
MOC071-099-071500-
/O.NEW.KLSX.SV.W.0020.150407T1418Z-150407T1500Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
918 AM CDT TUE APR 7 2015

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL FRANKLIN COUNTY IN EAST CENTRAL MISSOURI...
  NORTHWESTERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 1000 AM CDT

* AT 915 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR ST. CLAIR...
  AND MOVING EAST AT 40 MPH.

  HAZARD...HALF DOLLAR SIZE HAIL.

  SOURCE...RADAR INDICATED.

  IMPACT...DAMAGE TO VEHICLES IS EXPECTED.

* LOCATIONS IMPACTED INCLUDE...
  ST. CLAIR...VILLA RIDGE...PACIFIC...CEDAR HILL...BYRNES MILL...
  HILLSBORO...PARKWAY...LONEDELL...DITTMER...HOUSE SPRINGS...PINEY
  PARK...MOSELLE...ROBERTSVILLE...CATAWISSA...GRUBVILLE...OERMANN...
  MORSE MILL AND SCOTSDALE.

THIS WARNING INCLUDES ROBERTSVILLE STATE PARK.

THIS WARNING ALSO INCLUDES...
INTERSTATE 44 FROM EXIT 239 TO EXIT 253.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3832 9117 3850 9101 3848 9072 3846 9069
      3845 9069 3846 9068 3845 9068 3846 9066
      3847 9065 3846 9048 3819 9057
TIME...MOT...LOC 1418Z 277DEG 34KT 3838 9100

HAIL...1.25IN
WIND...<50MPH

$$

GLASS

2 follow-up statements

425 
WWUS53 KLSX 071439
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
939 AM CDT TUE APR 7 2015

MOC071-099-071500-
/O.CON.KLSX.SV.W.0020.000000T0000Z-150407T1500Z/
FRANKLIN MO-JEFFERSON MO-
939 AM CDT TUE APR 7 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHWESTERN
JEFFERSON AND EAST CENTRAL FRANKLIN COUNTIES UNTIL 1000 AM CDT...

AT 937 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR ST. CLAIR...
AND MOVING EAST AT 40 MPH.

HAZARD...PING PONG BALL SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...PEOPLE AND ANIMALS OUTDOORS WILL BE INJURED. EXPECT DAMAGE
         TO ROOFS...SIDING...WINDOWS AND VEHICLES.

LOCATIONS IMPACTED INCLUDE...
PACIFIC...CEDAR HILL...BYRNES MILL...HILLSBORO...LONEDELL...
DITTMER...HOUSE SPRINGS...ROBERTSVILLE...CATAWISSA...GRUBVILLE...
OERMANN...MORSE MILL AND SCOTSDALE.

THIS WARNING INCLUDES ROBERTSVILLE STATE PARK.

THIS WARNING ALSO INCLUDES...
INTERSTATE 44 FROM EXIT 239 TO EXIT 253.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3832 9116 3849 9092 3848 9072 3845 9068
      3847 9065 3846 9048 3819 9057
TIME...MOT...LOC 1439Z 277DEG 34KT 3837 9088

HAIL...1.50IN
WIND...<50MPH

$$

GLASS

359 
WWUS53 KLSX 071448
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
948 AM CDT TUE APR 7 2015

MOC071-099-071500-
/O.CON.KLSX.SV.W.0020.000000T0000Z-150407T1500Z/
FRANKLIN MO-JEFFERSON MO-
948 AM CDT TUE APR 7 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHWESTERN
JEFFERSON AND EAST CENTRAL FRANKLIN COUNTIES UNTIL 1000 AM CDT...

AT 946 AM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR LONEDELL...AND
MOVING EAST AT 40 MPH.

HAZARD...PING PONG BALL SIZE HAIL.

SOURCE...TRAINED WEATHER SPOTTERS. QUARTER SIZE HAIL WAS REPORTED 
         ALONG INTERSTATE 44 AROUND 5 MILES NORTHEAST OF ST. CLAIR.

IMPACT...PEOPLE AND ANIMALS OUTDOORS WILL BE INJURED. EXPECT DAMAGE
         TO ROOFS...SIDING...WINDOWS AND VEHICLES.

LOCATIONS IMPACTED INCLUDE...
PACIFIC...CEDAR HILL...BYRNES MILL...HILLSBORO...DITTMER...HOUSE
SPRINGS...GRUBVILLE...OERMANN...SCOTSDALE AND MORSE MILL.

THIS WARNING INCLUDES ROBERTSVILLE STATE PARK.

THIS WARNING ALSO INCLUDES...
INTERSTATE 44 FROM EXIT 239 TO EXIT 251.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. PREPARE IMMEDIATELY FOR LARGE DESTRUCTIVE
HAIL CAPABLE OF PRODUCING SIGNIFICANT DAMAGE. PEOPLE OUTSIDE SHOULD
MOVE TO A SHELTER...INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 3832 9116 3849 9092 3848 9072 3845 9068
      3847 9065 3846 9048 3819 9057
TIME...MOT...LOC 1448Z 277DEG 34KT 3836 9080

HAIL...1.50IN
WIND...<50MPH

$$

GLASS

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 7, 6:49 AM CDT, 2 hours 29 minutes earlier.

Area forecast discussion, Apr 7, 6:49 AM CDT, 2 hours 29 minutes before

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
649 AM CDT Tue Apr 7 2015

.SHORT TERM:  (Through Tonight)
Issued at 343 AM CDT Tue Apr 7 2015

Starting to sound like a broken record, but once again, focus will
be precip chances thru the period.

Expect precip over the ern portions of the CWA to continue moving
out of the area early this morning. Some isod SHRA, and perhaps TS,
will be possible. However, main focus is expected to be the ongoing
TSRA over wrn MO. Numerous mdl solns suggest this cluster of TSRA
will lift enewd into the area this morning and build sewd late this
morning, perhaps into the afternoon, as the LLJ veers. However, some
question remains how far E and S these storms will propagate before
dissipating as the LLJ weakens. As these storms dissipate, expect a
lull this afternoon into the evening before the next round arrives.
Some question remains as to where/when TSRA will initiate, but best
chances shud be along the sfc boundary across the nrn portions of
the CWA, tho any outflow boundaries may also help initiate storms.
Have kept PoPs for tonight in the change range due to questions in
boundary locations.

Given the amount of elevated CAPE and deep shear available, a severe
threat will exist with hail and winds as a primary threat.

Little change in temps for today and tonight with continued trends
twd warm guidance.

Tilly

.LONG TERM:  (Wednesday through Monday)
Issued at 414 AM CDT Tue Apr 7 2015

Not many changes from the prev forecast. Still a number of
questions exist with upcoming system. A severe threat still exists
on Wed during the late afternoon and overnight period. The greater
threat still exists on Thurs as the cdfnt pushes thru the region.
Mdl solns have changed slightly from yesterday. Mdls have sped up
timing of fropa slightly, with bulk of precip expected to be E of
the CWA by 06z Fri. Mdls now have upper trof remaining neutral as
it approaches the region. Still, enuf CAPE and deep shear will
exist to pose a severe threat. Please see the latest SPC day 2 and
day 3 outlooks for the latest info as local thinking agrees with
SPC.

Mdl solns differ regarding timing of the next system Sat into Sun.
Have low PoPs early to account for the GFS soln and trended twd
higher PoPs where/when mdls are in better agreement.

Otherwise, have continued warm trend thru Thurs despite the ample
cloud cover expected. Cooler, but seasonal avg, temps are expected
this weekend as a large sfc ridge settles into the area.

Tilly

&&

.AVIATION:  (For the 12z TAFs through 12z Wednesday Morning)
Issued at 632 AM CDT Tue Apr 7 2015

Busy fcst prd over the next 24 hrs. Warm front currently lifting
north thru cntrl MO and sthrn IL with a significant TSTM rolling
east along the bndry. This storm has a history of producing 1-2
inch hail and should arrive in the wrn STL metro area around 13Z.
CIGs have been sporadic with VFR and LIFR conditions from west to
east across the STL metro area. Model guidance indicates plenty of
IFR/MVFR conditions thru the fcst prd but lack of verification
compared to current obs makes the CIG fcst low confidence. Think
the general trend will be for CIGs to slowly rise today as the
warm front lifts north only to build back down tonight. Pattern is
conducive for scttrd convection just about anytime...but think the
best chances will be tied to the warm front and should be confined
to area along and north of I70.

Specifics for KSTL:

Sporadic CIGs this mrng are expected to rise as a warm front
lifts north...though the CIG fcst is low confidence due to poor
model performance compared to currently obs. A significant TSTM is
riding east along the bndry and should be near the terminal around
14Z. This storm has a history of producing 1-2 inch hail. The
overall pattern is such that SHRA/TSTMs are possible just about
anywhere at anytime but think the best chances this prd should be
tied to the warm front. With that bndry lifting north this
mrng...chances should decrease after this mrngs activity.

2%

&&

.PRELIMINARY POINT TEMPS/POPS:
Saint Louis     80  64  81  68 /  60  40  50  70
Quincy          74  60  77  62 /  60  40  60  80
Columbia        79  62  80  64 /  60  40  60  70
Jefferson City  80  63  81  65 /  50  40  60  70
Salem           77  62  79  66 /  50  40  30  70
Farmington      78  62  81  65 /  40  30  30  60

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

WFO LSX

Hazardous weather outlook, Apr 7, 4:13 AM CDT, 5 hours 5 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
413 AM CDT TUE APR 7 2015

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-081200-
GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL-
MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL-
CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX MO-
LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO-
AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO-
LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO-
ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO-
WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO-
MADISON MO-REYNOLDS MO-
413 AM CDT TUE APR 7 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND
CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE LIKELY THIS MORNING ACROSS PORTIONS OF CENTRAL
AND EASTERN MISSOURI AS WELL AS NORTH CENTRAL AND SOUTHWEST
ILLINOIS. THERE IS A CHANCE FOR THUNDERSTORMS ACROSS THE AREA TONIGHT.
A FEW OF THE STORMS MAY BECOME STRONG TO SEVERE..WITH LARGE HAIL
BEING THE PRIMARY SEVERE WEATHER THREAT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THUNDERSTORMS ARE LIKELY OVER MUCH OF THE AREA FROM WEDNESDAY
AFTERNOON...THURSDAY...AND INTO THURSDAY NIGHT. SOME OF THE THUNDERSTORMS
MAY BE SEVERE WEDNESDAY NIGHT...AND AGAIN ON THURSDAY AND INTO
THURSDAY NIGHT.

THE CHANCE FOR THUNDERSTORMS RETURNS SUNDAY THROUGH MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE REQUESTED TO REPORT ANY HAIL THAT THEY OBSERVE
THROUGH TONIGHT.

TILLY

In the hours before

Local storm report, Apr 7, 9:05 AM CDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
905 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0856 AM     HAIL             6 SSW WRIGHT CITY       38.75N  91.07W
04/07/2015  E1.75 INCH       WARREN             MO   PUBLIC

            ESTIMATED SIZE FROM TWITTER POST IN THE INNSBROOK AREA.

&&

FUCHS

Local storm report, Apr 7, 9:08 AM CDT, 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
908 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0902 AM     HAIL             6 E AUGUSTA             38.57N  90.77W
04/07/2015  E1.25 INCH       FRANKLIN           MO   TRAINED SPOTTER

&&

FUCHS

Local storm report, Apr 7, 9:11 AM CDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
911 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0911 AM     HAIL             UNION                   38.45N  91.01W
04/07/2015  E0.25 INCH       FRANKLIN           MO   TRAINED SPOTTER

&&

TRUETT

Local storm report, Apr 7, 9:12 AM CDT, 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
912 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0853 AM     HAIL             2 SW LAKE ST. LOUIS     38.77N  90.81W
04/07/2015  E0.50 INCH       ST. CHARLES        MO   TRAINED SPOTTER

            PARKGATE DRIVE.

&&

FUCHS

Local storm report, Apr 7, 9:14 AM CDT, 4 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
914 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0900 AM     TSTM WND DMG     6 E AUGUSTA             38.57N  90.77W
04/07/2015                   FRANKLIN           MO   TRAINED SPOTTER

            2-INCH OR BIGGER TREE LIMBS AND BRANCHES BLOWN DOWN.

&&

FUCHS

Local storm report, Apr 7, 9:16 AM CDT, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
916 AM CDT TUE APR 07 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 AM     HAIL             POTOSI                  37.94N  90.78W
04/07/2015  E0.25 INCH       WASHINGTON         MO   TRAINED SPOTTER

            HAIL WAS BETWEEN DESOTO AND POTOSI MISSOURI.

&&

DYE

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 7, 4:59 AM CDT	Severe Thunderstorm Warning	LSX	Boone	46 min
Apr 7, 5:34 AM CDT	Severe Thunderstorm Warning	LSX	Audrain, Callaway	56 min
Apr 7, 6:23 AM CDT	Severe Thunderstorm Warning	LSX	Callaway, Montgomery	67 min
Apr 7, 7:06 AM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Montgomery, Warren	54 min
Apr 7, 7:56 AM CDT	Severe Thunderstorm Warning	LSX	Franklin, Saint Charles, Saint Louis, Warren	49 min
Apr 7, 8:42 AM CDT	Severe Thunderstorm Warning	LSX	Franklin, Jefferson, Saint Charles, Saint Louis	48 min
Apr 7, 9:26 AM CDT	Severe Thunderstorm Warning	LSX	Jefferson, Saint Louis, City of Saint Louis	49 min
Apr 7, 9:42 AM CDT	Flash Flood Warning	LSX	Franklin, Jefferson, Saint Charles, Saint Louis, Warren	8 hr
Apr 7, 9:58 AM CDT	Severe Thunderstorm Warning	LSX	Franklin, Jefferson	47 min
Apr 7, 10:03 AM CDT	Severe Thunderstorm Warning	LSX	Saint Louis, City of Saint Louis	42 min
Apr 7, 10:43 AM CDT	Areal Flood Advisory	LSX	Saint Louis, City of Saint Louis	4 hr
Apr 7, 10:53 AM CDT	Flash Flood Warning	LSX	Crawford, Franklin, Jefferson, Washington	4 hr
Apr 7, 12:42 PM CDT	River Flood Warning	LSX	Saint Charles	35 hr
Apr 7, 12:47 PM CDT	Flash Flood Warning	LSX	Jefferson, Sainte Genevieve, Saint Francois, Washington	6 hr

Nearby

Severe Thunderstorm Warnings in Missouri, 2015 Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.