Alert archive / Illinois / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 237, NWS St. Louis, MO

October 18, 2007Macoupin County, Montgomery County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Oct 18, 2007, 2:05 AM CDT for Macoupin County, Montgomery County, Illinois. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Oct 18, 2007, 2:05 AM CDT (07:05 UTC)
Expired: Oct 18, 2007, 2:45 AM CDT
In force: 40 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon

Counties Macoupin County, IL, Montgomery County, IL

The radar

The Lincoln radar (KILX), 104 km from the middle of the area, began a volume at 07:06 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

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
Oct 17, 11:40 PM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 7.1 hours before the alert went out and 137 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: 579 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 645 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 336 m²/s²
0-3 km storm-relative helicity: 386 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 7.2

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KLSX 180705
SVRLSX
ILC117-135-180745-
/O.NEW.KLSX.SV.W.0237.071018T0705Z-071018T0745Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
205 AM CDT THU OCT 18 2007

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MONTGOMERY COUNTY IN SOUTH CENTRAL ILLINOIS
  MACOUPIN COUNTY IN SOUTHWEST ILLINOIS

* UNTIL 245 AM CDT

* AT 203 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 8 MILES NORTHWEST OF PALMYRA TO 10 MILES SOUTHWEST OF 
  BUNKER HILL...AND MOVING EAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  SHIPMAN...
  PALMYRA...
  BUNKER HILL...
  WILSONVILLE...
  CARLINVILLE...
  GIRARD...
  GILLESPIE...
  BENLD...
  VIRDEN...
  MOUNT OLIVE...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. IF A TORNADO
IS SPOTTED... ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A STURDY
STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

LAT...LON 3901 9013 3954 9013 3953 8954 3935 8952
      3936 8926 3903 8927
TIME...MOT...LOC 0705Z 270DEG 40KT 3950 9009 3897 9009

$$

TRUETT

1 follow-up statement

000 
WWUS53 KLSX 180744
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
245 AM CDT THU OCT 18 2007

ILC117-135-180755-
/O.EXP.KLSX.SV.W.0237.000000T0000Z-071018T0745Z/
MONTGOMERY IL-MACOUPIN IL-
245 AM CDT THU OCT 18 2007

...THE SEVERE THUNDERSTORM WARNING FOR MACOUPIN AND MONTGOMERY
COUNTIES EXPIRED AT 245 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAD WEAKENED AND NO LONGER
APPEARED TO BE SEVERE.

HOWEVER...STRONG THUNDERSTORMS ARE STILL POSSIBLE...ESPECIALLY OVER 
MONTGOMERY COUNTY...AND A TORNADO WATCH REMAINS IN EFFECT UNTIL 6 AM.

LAT...LON 3901 9013 3954 9013 3953 8954 3935 8952
      3936 8926 3903 8927
TIME...MOT...LOC 0744Z 270DEG 40KT 3950 8953 3897 8953

$$

TRUETT

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 Oct 18, 12:09 AM CDT, 1 hour 56 minutes earlier.

Area forecast discussion, Oct 18, 12:09 AM CDT, 1 hour 56 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
1209 AM CDT THU OCT 18 2007

.UPDATE...
GOING CATEGORICAL FORECAST FOR TONIGHT STILL LOOKS ON TRACK AS
LARGE SCALE ASCENT WILL INCREASE IN ADVANCE OF NEGATIVELY TILTED
TROUGH AND JET STREAK CURRENTLY ROTATING OUT OF THE CENTRAL
PLAINS. LARGE AREA OF SHOWERS AND SCATTERED TSRA OVER SERN HALF OF
THE CWA IS IN RESPONSE TO STRONG 925-850MB MOISTURE CONVERGENCE
THAT IS PROGGED TO CONTINUE THROUGH 09Z.

AS EXPECTED...INSTABILITY IS NOT GREAT WITH MUCAPES ONLY RUNNING
BETWEEN 500-1000 J/KG...THOUGH DO NOT EXPECT IT TO FALL MUCH MORE
TONIGHT AS LOW LEVEL WINDS CONTINUE TO ADVECT MID-UPPER 60
DEWPOINTS INTO CWA.  IMPRESSIVE DEEP LAYER SHEAR (0-6KM SHEAR OF
40-60KTS) AND ASCENT FROM SHORTWAVE WILL AUGMENT MARGINAL
INSTABILITY TO KEEP RISK OF SEVERE WEATHER THROUGH THE NIGHT.
LATEST SWODY1 MOVED MDT RISK INTO THE SWRN QUARTER OF THE CWA.
THERE WILL CONTINUE TO BE A THREAT OF TORNADOES THROUGH THE NIGHT
GIVEN THE IMPRESSIVE 250-400 M2/S2 0-1KM SRH VALUES. WILL ALSO
MENTION OF LOCALLY HEAVY RAINFALL IN THE HWO AS VSBY AT OBS SITES
HAVE BEEN FALLING WITH +RA...AND PRECIP H20 VALUES ARE NEAR 2
INCHES OVER THE ERN PART OF THE CWA.

STILL QUESTIONS ABOUT TIMING OF FRONT TOMORROW. NEW 00Z RUN OF NAM
HOLDS FRONT AND INSTABILITY FARTHER WEST OVER THE REGION THROUGH
21Z TOMORROW...SO WILL GO AHEAD AND INCREASE POPS OVER IL COUNTIES
THROUGH TOMORROW AFTN.

BRITT
&&

.DISCUSSION...
A SURFACE LOW PRESSURE SYSTEM WAS LOCATED OVER NORTHWESTERN KS
THIS AFTERNOON. A WARM FRONT EXTENDED FROM THE LOW ACROSS
NORTHWEST INTO SOUTHEAST MO. LOW AND TRAILING COLD FRONT WILL MOVE
NORTHEASTWARD TONIGHT AND ON THURSDAY. BY THURSDAY EVENING, LOW IS
FORECAST TO BE CENTERED OVER SOUTHEAST MN WITH THE COLD FRONT
EXTENDING FROM NORTHEAST IL ACROSS SOUTHEAST MO.

SIGNIFICANT LOW LEVEL MOISTURE WAS BEING ADVECTED NORTHWARD ACROSS
THE LOWER MS VALLEY/SOUTHERN GREAT PLAINS. 850 DEWPOINTS WERE IN THE
MID TEENS C THIS MORNING ACROSS THAT REGION WITH A 40+ KT JET
EXTENDING FROM OK INTO SOUTHWEST IA. THE GFS AND UKMET ARE FAIRLY
SIMILAR FOR THIS EVENING WITH TREMENDOUS MOISTURE
ADVECTION/CONVERENCE FORECAST ACROSS INTO THE AREA. MOST OF THE
FORECAST AREA IS RAIN FREE NOW.

UPPER SHORT WAVE WAS LOCATED OVER THE SOUTHERN ROCKIES/HIGH PLAINS
OF OK AND TX THIS MORNING. MODELS ARE SIMILAR IN AMPLIFYING SYSTEM
AND CLOSING OFF AN UPPER LOW OVER EASTERN NEB ON THURSDAY MORNING
WITH A 140-160 METER HEIGHT FALL CENTER OVER NORTHEAST MO. VIGOROUS
LOW WILL LIFT INTO THE UPPER MIDWEST BY FRIDAY MORNING.  SURFACE LOW
WILL DEEPEN DRAMATICALLY OVERNIGHT AND ON THURSDAY AS A RESULT.

THE EUROPEAN IS STRONGER WITH THE NEXT SHORT WAVE LATER IN THE
WEEKEND. THE MODEL FORECASTS A CLOSED LOW DEVELOPING OVER CO BY
SUNDAY MORNING WHILE THE GFS IS MUCH WEAKER WITH SYSTEM. SIGNIFICANT
DIFFERENCES APPEAR EARLY NEXT WEEK BETWEEN THE GFS AND EUROPEAN
MODELS. THE EUROPEAN KEEPS A CLOSED LOW OVER THE SOUTHERN
PLAINS/SOUTHERN ROCKIES WHILE THE GFS HAS CLOSED LOW OVER THE
APPLACHIANS.

TPS
&&

.AVIATION...
FOR THE 06Z TAFS...
A LINE OF STRONG TO SEVERE THUNDERSTORMS IS NOW MOVING ACROSS THE
FORECAST AREA. THE POTENTIAL STILL EXISTS FOR SEVERE CONVECTION WITH
WINDS IN EXCESS OF 50 KTS...AND POSSIBLY TORNADOES AS WELL...
ESPECIALLY FOR KSTL AND KSUS. PCPN SHOULD COME TO AN END FROM WEST
TO EAST BETWEEN 09Z AND 13Z. OTHWERWISE...SURFACE WINDS WILL BE
QUITE GUSTY BY DAYBREAK AS THE STORM SYSTEM CONTINUES TO DEEPEN AND
MOVE NORTHEAST. CURRENT INDICATIONS ARE THAT THE WINDS COULD GUST TO
MORE THAN 30 KTS IN SOME PLACES. AS FOR CIGS...MVFR CIGS TO IMPROVE
BY MID MORNING...THEN LOWER BACK DOWN TO LOW MVFR AFTER 01Z AS WRAP
AROUND CLOUDS MOVE IN ON BACK SIDE OF SYSTEM.

BYRD
&&

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

WFO LSX

Hazardous weather outlook, Oct 17, 10:05 PM CDT, 4 hours before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
1005 PM CDT WED OCT 17 2007

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-181215-
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-LEWIS-
SHELBY-MARION-MONROE-RALLS-PIKE-BOONE-AUDRAIN-MONITEAU-COLE-OSAGE-
CALLAWAY-MONTGOMERY-LINCOLN-GASCONADE-WARREN-ST. CHARLES-FRANKLIN-
ST. LOUIS-ST. LOUIS CITY-JEFFERSON-CRAWFORD-WASHINGTON-
ST. FRANCOIS-STE. GENEVIEVE-IRON-MADISON-REYNOLDS-
1005 PM CDT WED OCT 17 2007

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

.DAY ONE...TONIGHT
OCCASIONAL THUNDERSTORMS ARE EXPECTED TO CONTINUE THE REST OF THE
NIGHT. A FEW OF THESE STORMS WILL BE SEVERE...CAPABLE OF PRODUCING
TORNADOES...LARGE HAIL AND DAMAGING WIND GUSTS TO 70 MPH. THE
GREATEST RISK FOR SEVERE WEATHER WILL BE SOUTH OF INTERSTATE 70
IN MISSOURI AND SOUTH OF INTERSTATE 64 IN ILLINOIS. LOCALLY HEAVY
RAINFALL IS ALSO POSSIBLE WITH THESE STORMS.

INFORMATION ON CONVECTIVE WATCHES...PLEASE REFER TO THE STORM
PREDICTION CENTER WEBPAGE AT (ALL LOWERCASE)...
HTTP://WWW.SPC.NOAA.GOV/PRODUCTS/WATCH.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TO THE EAST OF THE
MISSISSIPPI RIVER ON THURSDAY.

SOUTHWEST WINDS WILL GUST TO 30 TO 40 MPH ON THURSDAY.

THERE IS ANOTHER CHANCE OF THUNDERSTORMS FROM SUNDAY NIGHT
THROUGH MONDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY.

&&

FOR A GRAPHICAL VERSION OF THIS INFORMATION SEE OUR
WEBPAGE AT (LOWERCASE)... HTTP://WWW.WEATHER.GOV/LSX/?N=HWO1

BRITT

In the hours before

Local storm report, Oct 18, 1:09 AM CDT, 56 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
109 AM CDT THU OCT 18 2007

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

1250 AM     TSTM WND DMG     BOWLING GREEN           39.34N 91.20W
10/18/2007                   PIKE               MO   LAW ENFORCEMENT

            POWER LINES DOWN

&&

BRITT

Local storm report, Oct 18, 1:10 AM CDT, 55 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE ST LOUIS MO
110 AM CDT THU OCT 18 2007

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

1250 AM     TSTM WND DMG     BOWLING GREEN           39.34N 91.20W
10/18/2007                   PIKE               MO   LAW ENFORCEMENT

            POWER LINES DOWN

&&

BRITT

Local storm report, Oct 18, 1:21 AM CDT, 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
121 AM CDT THU OCT 18 2007

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

0100 AM     TSTM WND DMG     HILLSBORO               38.23N 90.57W
10/18/2007                   JEFFERSON          MO   LAW ENFORCEMENT

            TOP OF TREE TAKEN DOWN ALONG HIGHWAY A.

&&

BRITT

Local storm report, Oct 18, 1:24 AM CDT, 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
124 AM CDT THU OCT 18 2007

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

0100 AM     TSTM WND DMG     1 S WARRENTON           38.81N 91.14W
10/18/2007                   WARREN             MO   TRAINED SPOTTER

            POWER LINE DOWN AND TREE ACROSS HIGHWAY F.

&&

BRITT

Local storm report, Oct 18, 1:33 AM CDT, 32 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
133 AM CDT THU OCT 18 2007

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

0110 AM     TSTM WND DMG     NEW CANTON              39.64N 91.10W
10/18/2007                   PIKE               IL   LAW ENFORCEMENT

            TREE DOWN ACROSS ROAD.

&&

BRITT

Local storm report, Oct 18, 2:02 AM CDT, 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
202 AM CDT THU OCT 18 2007

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

1200 AM     TSTM WND DMG     FULTON                  38.85N 91.95W
10/18/2007                   CALLAWAY           MO   FIRE DEPT/RESCUE

            CONCENTRATED DAMAGE PATH ABOUT A QUARTER OF MILE WIDE
            FROM FULTON TO CALWOOD ALONG HIGHWAY Z. NUMEROUS
            TREES...TREE LIMBS AND POWER LINES DOWN.

1200 AM     TSTM WND DMG     3 NW KINGDOM CITY       38.98N 91.98W
10/18/2007                   CALLAWAY           MO   LAW ENFORCEMENT

            TREES BLOWN OVER ON HOUSES ALONG COUNTY ROAD 254 NEAR
            HEREFORD. TIME ESTIMATED.

0130 AM     TSTM WND DMG     1 W FIELDON             39.11N 90.52W
10/18/2007                   JERSEY             IL   LAW ENFORCEMENT

            TREE UPROOTED BLOCKING HIGHWAY 16.

&&

BRITT

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 18, 12:30 AM CDT	Severe Thunderstorm Warning	LSX	Adams, Calhoun, Pike	45 min
Oct 18, 1:12 AM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Pike	63 min
Oct 18, 1:14 AM CDT	Severe Thunderstorm Warning	LSX	Madison, Monroe, Saint Clair	61 min
Oct 18, 4:23 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Madison, Saint Clair	37 min
Oct 18, 4:55 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Fayette, Madison, Montgomery	50 min
Oct 18, 5:05 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Fayette, Madison, Marion, Saint Clair	40 min
Oct 18, 5:06 PM CDT	Severe Thunderstorm Warning	LSX	Randolph, Washington	24 min
Oct 18, 5:11 PM CDT	Severe Thunderstorm Warning	LSX	Randolph	19 min
Oct 18, 5:22 PM CDT	Tornado Warning	LSX	Bond, Fayette	38 min
Oct 18, 5:31 PM CDT	Tornado Warning	LSX	Bond, Clinton, Fayette, Marion	44 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2007 Every severe thunderstorm warning in 2007

Sources

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