Alert archive / Illinois / Mesoscale Discussions in 2013
Mesoscale Discussion 708
The Storm Prediction Center issued this mesoscale discussion at May 19, 2013, 6:08 PM CDT for 10 counties in Illinois. It was in force for 67 min.
The area
The outline as issued.
The facts
- Issued
- May 19, 2013, 6:08 PM CDT (23:08 UTC)
- Expired
- May 19, 2013, 7:15 PM CDT
- In force
- 67 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
Counties Bureau County, IL, Fulton County, IL, Knox County, IL, Lee County, IL, Marshall County, IL, Peoria County, IL, Putnam County, IL, Stark County, IL, Tazewell County, IL, Woodford County, IL
The radar
The Lincoln radar (KILX), 100 km from the middle of the area, began a volume at 23:10 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 11.1 hours before the alert went out and 97 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.
- Mixed-layer CAPE
- 905 J/kg
- Mixed-layer CIN
- -122 J/kg
- Mixed-layer LCL
- 846 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 102 m²/s²
- 0-3 km storm-relative helicity
- 93 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
348
ACUS11 KWNS 192309
SWOMCD
SPC MCD 192308
ILZ000-200015-
MESOSCALE DISCUSSION 0708
NWS STORM PREDICTION CENTER NORMAN OK
0608 PM CDT SUN MAY 19 2013
AREAS AFFECTED...CNTRL INTO NRN IL
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 192308Z - 200015Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...TSTMS INTENSIFYING ALONG THE MS RIVER BETWEEN MLI AND UIN
MAY MOVE OUT OF TORNADO WATCH 183 PRIOR TO 00Z. CONVECTIVE TRENDS
ARE BEING MONITORED FOR A POSSIBLE WW.
DISCUSSION...AS OF 2245Z...RADAR DATA INDICATED A CLUSTER OF
INTENSIFYING TSTMS FROM ROCK ISLAND AND MERCER COUNTIES TO HANCOCK
COUNTY IL. THE ANCHOR STORM OF THIS CLUSTER OVER HANCOCK COUNTY HAS
RECENTLY EXHIBITED RIGHTWARD PROPAGATION...SUGGESTING EVOLUTION INTO
A SUPERCELL. AREA VAD DATA AND MODEL-DERIVED FORECAST SOUNDINGS
INDICATE A ENVIRONMENT FOR UPDRAFT SUSTENANCE/ROTATION WITH A
MODERATELY UNSTABLE AIR MASS WHICH COINCIDES WITH A VERTICALLY
VEERING WIND PROFILE AND 40-45 KT OF DEEP-LAYER SHEAR. EXPECT
VERTICAL SHEAR TO FURTHER STRENGTHEN THROUGH THIS EVENING AS THE
EXIT REGION OF A 40-50 KT LLJ DEVELOPS NEWD INTO THE REGION. AS
SUCH...EXPECT THE POTENTIAL FOR ORGANIZED STORM MODES...INCLUDING
SUPERCELLS TO PERSIST THROUGH THIS EVENING AND POSSIBLY DEVELOP EAST
OF TORNADO WATCH 183 BY 00Z.
..MEAD/CORFIDI.. 05/19/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...ILX...DVN...
LAT...LON 40899030 41498963 41838940 41708887 41218890 40478936
40248995 40399033 40899030SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 19, 11:30 AM CDT | Mesoscale Discussion | SPC | Adams, Hancock, Henderson, Mercer, Pike | 90 min |
| May 19, 2:59 PM CDT | Tornado Watch | SPC | Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more | 8 hr |
| May 19, 6:25 PM CDT | Tornado Watch | SPC | Adams, Brown, Calhoun, Pike | 9 hr |
Nearby
Mesoscale Discussions in Illinois, 2013Every mesoscale discussion in 2013
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.