Alert archive / Missouri / Mesoscale Discussions in 2011

Mesoscale Discussion 66

February 1, 20115 counties in Arkansas; 11 counties in Illinois; 28 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Feb 1, 2011, 6:54 AM CST for 5 counties in Arkansas; 11 counties in Illinois; 28 counties in Missouri. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Feb 1, 2011, 6:54 AM CST (12:54 UTC)
Expired
Feb 1, 2011, 11:30 AM CST
In force
5 hr
Issued by
the Storm Prediction Center
All 44 counties

Boone County, AR, Carroll County, AR, Madison County, AR, Marion County, AR, Washington County, AR, Bond County, IL, Clinton County, IL, Fayette County, IL, Jersey County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Christian County, MO, City of Saint Louis, MO, Crawford County, MO, Dent County, MO, Douglas County, MO, Franklin County, MO, Gasconade County, MO, Howell County, MO, Iron County, MO, Jefferson County, MO, Laclede County, MO, Madison County, MO, Maries County, MO, Ozark County, MO, Phelps County, MO, Pulaski County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shannon County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Washington County, MO, Webster County, MO, Wright County, MO

The radar

The St Louis radar (KLSX), 118 km from the middle of the area, began a volume at 12:53 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 nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 0.9 hours before the alert went out and 245 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-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2011-02-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 12:00Z on 2011-02-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 231 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
535 m above ground
0-6 km bulk shear
74 kt
0-1 km storm-relative helicity
231 m²/s²
0-3 km storm-relative helicity
308 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.

149 
ACUS11 KWNS 011254
SWOMCD
SPC MCD 011254 
ILZ000-MOZ000-ARZ000-011730-

MESOSCALE DISCUSSION 0066
NWS STORM PREDICTION CENTER NORMAN OK
0654 AM CST TUE FEB 01 2011

AREAS AFFECTED...NWRN AR...SRN/ERN MO...SWRN IL

CONCERNING...WINTER MIXED PRECIPITATION 

VALID 011254Z - 011730Z

A RELATIVELY NARROW CORRIDOR OF SLEET/FREEZING RAIN WILL PERSIST
BETWEEN BANDS OF HEAVY SNOW/BLIZZARD CONDITIONS TO THE NW /REF MCD
0064/ AND RAIN TO THE SE. LIQUID EQUIVALENT RATES AOA 0.10 IN/HR
WILL REMAIN LIKELY.

12Z SURFACE ANALYSIS PLACED A 999 MB CYCLONE IN FAR NERN TX WITH
QUASI-STATIONARY FRONT EXTENDING NEWD ACROSS CNTRL AR TOWARDS THE OH
VALLEY. WITH THE CYCLONE EXPECTED TO TRACK NEWD ALONG THE FRONT
THROUGH 18Z...LOW-LEVEL THERMAL STRUCTURE TO THE N/NE OF THE CYCLONE
FROM S-CNTRL MO INTO SWRN IL SHOULD SLOWLY COOL AS SWATHS OF
MODERATE PRECIPITATION CONTINUE TO SPREAD N/NEWD. 12Z SGF RAOB
SAMPLED A SMALL ABOVE-FREEZING WARM NOSE /AROUND 1 DEG C AT 825
MB/...SUPPORTIVE OF AROUND A 50 MILE CORRIDOR OF SLEET FROM SWRN
INTO E-CNTRL MO. THIS SLEET CORRIDOR SHOULD PIVOT INTO NWRN AR /PER
03Z SREF LIKELY PTYPE/...RELEGATING PREDOMINANT FREEZING RAIN TO
S-CNTRL MO INTO SRN IL.

..GRAMS.. 02/01/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PAH...ILX...LSX...LZK...SGF...TSA...

LAT...LON   36119438 37189336 38239202 38999068 39348957 39348912
            39178879 38958852 38668861 38428889 37609008 36269244
            35859349 35729409 36119438

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 31, 10:36 PM CSTMesoscale DiscussionSPCBenton, Washington5 hr
Feb 1, 6:46 AM CSTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 13 more119 min
Feb 1, 1:11 PM CSTMesoscale DiscussionSPCBenton4 hr
Feb 1, 10:36 AM CSTMesoscale DiscussionSPCAdams, Brown, Bureau, Calhoun, Cass, Fulton and 24 more6 hr
Feb 1, 11:42 AM CSTMesoscale DiscussionSPCBond, Champaign, Christian, Clark, Clay, Clinton and 27 more5 hr
Feb 1, 3:36 PM CSTMesoscale DiscussionSPCAdams, Boone, Brown, Bureau, Calhoun, Carroll and 49 more6 hr
Feb 1, 3:11 AM CSTMesoscale DiscussionSPCBarton, Bates, Benton, Boone, Camden, Cass and 22 more6 hr

Nearby

Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Illinois, 2011Mesoscale Discussions in Arkansas, 2011Every mesoscale discussion in 2011

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.