Alert archive / Mississippi / Mesoscale Discussions in 2011
Mesoscale Discussion 87
The Storm Prediction Center issued this mesoscale discussion at Feb 4, 2011, 5:28 AM CST for 7 states. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 4, 2011, 5:28 AM CST (11:28 UTC)
- Expired
- Feb 4, 2011, 11:00 AM CST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 158 counties
Franklin County, AL, Lamar County, AL, Marion County, AL, Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jefferson County, AR, Lafayette County, AR, Lee County, AR, Lincoln County, AR, Little River County, AR, Lonoke County, AR, Miller County, AR, Monroe County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Pike County, AR, Polk County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Sevier County, AR, St. Francis County, AR, Union County, AR, Avoyelles Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Tensas Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Alcorn County, MS, Amite County, MS, Attala County, MS, Benton County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Claiborne County, MS, Clay County, MS, Coahoma County, MS, Copiah County, MS, DeSoto County, MS, Franklin County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Itawamba County, MS, Jefferson County, MS, Kemper County, MS, Lafayette County, MS, Lawrence County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Marshall County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Warren County, MS, Washington County, MS, Webster County, MS, Wilkinson County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS, Atoka County, OK, Choctaw County, OK, Latimer County, OK, LeFlore County, OK, McCurtain County, OK, Pushmataha County, OK, Shelby County, TN, Bowie County, TX, Camp County, TX, Cass County, TX, Delta County, TX, Fannin County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Hopkins County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Panola County, TX, Rains County, TX, Red River County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX
The radar
The Little Rock radar (KLZK), 144 km from the middle of the area, began a volume at 11:31 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
Shreveport, LA (KSHV), launched 00:00Z, 11.5 hours before the alert went out and 182 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 899 m above ground
- 0-6 km bulk shear
- 92 kt
- 0-1 km storm-relative helicity
- 172 m²/s²
- 0-3 km storm-relative helicity
- 222 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
597
ACUS11 KWNS 041128
SWOMCD
SPC MCD 041128
ALZ000-TNZ000-MSZ000-ARZ000-LAZ000-TXZ000-OKZ000-041700-
MESOSCALE DISCUSSION 0087
NWS STORM PREDICTION CENTER NORMAN OK
0528 AM CST FRI FEB 04 2011
AREAS AFFECTED...PORTIONS NE TX...SERN OK...CENTRAL/SRN
AR...CENTRAL/NRN LA...CENTRAL/NRN MS...EXTREME SWRN TN...EXTREME
NWRN AL.
CONCERNING...WINTER MIXED PRECIPITATION
VALID 041128Z - 041700Z
FREEZING RAIN WITH GEN .05-.10 INCH/HOUR RATES SHOULD CONTINUE OVER
BROAD SWATH FROM S-CENTRAL LA NEWD ACROSS W-CENTRAL
MS...MOVING/EXPANDING NEWD OVER MORE OF N-CENTRAL AND CENTRAL MS
THROUGH ABOUT 16Z. EMBEDDED CONVECTIVE BURSTS...SOME WITH
THUNDER...BRIEFLY WILL OFFER .10-.25 INCH/HOUR FREEZING RAIN RATES.
FREEZING RAIN WILL GRADE TO SNOW WWD ACROSS PORTIONS EXTREME
N-CENTRAL/NWRN LA AND S-CENTRAL/SERN AR. SNOW RATES MAY REACH 1
INCH/HOUR IN HEAVIEST EMBEDDED BANDS AND SWATHS WWD ACROSS RED RIVER
REGION OF NE TX AND SWRN OK...SWD TO NEAR I-20.
BROAD PLUME OF PRECIP RELATED TO ELEVATED WAA/ASCENT AND MOISTURE
TRANSPORT ALOFT IS EXPECTED TO EXPAND NEWD ACROSS ARKLATEX
RETION...AR...AND MS AT FASTER RATE THAN ITS GENESIS REGION SHIFTS
EWD ONLY VERY SLOWLY ACROSS LA AND E TX. LARGE-SCALE ASCENT RELATED
TO DCVA...IMMEDIATELY PRECEDING MID-UPPER CYCLONE THAT IS EJECTING
NEWD FROM W TX...ALSO WILL CONTRIBUTE TO ASCENT OVER WRN PORTIONS OF
DISCUSSION AREA. NET EFFECT SHOULD BE EXPANSION OF ONGOING PRECIP
PLUME...WHILE WET-BULB EFFECTS LEAD TO ADDITIONAL BOUNDARY-LAYER
COOLING OVER MUCH OF THIS AREA. MODIFIED RUC/ETA-KF FCST SOUNDINGS
INDICATE NEARLY 9 KFT DEEP SUPERFREEZING LAYER OVER PORTIONS SRN
MS...TRENDING TO AROUND 4-5 KFT OVER CENTRAL LA AND DISAPPEARING
OVER E TX AND NWRN LA...IN GOOD AGREEMENT WITH CURRENT TRANSITION
ZONE FROM FREEZING RAIN TO SNOW. THIS TRANSITION ZONE...WHICH ALSO
CORRESPONDS TO SATURATION/LIFT NEAR BASE OF DENDRITIC GROWTH LAYERS
ALOFT...SHOULD DRIFT EWD ACROSS NRN LA AND SRN AR. LTG DETECTION
EQUIPMENT ALSO HAS OBSERVED CG STROKES DURING PAST HOUR FROM MORE
DISCRETELY CELLULAR CONVECTION FORMING INVOF POE...AND MOVING
RAPIDLY NEWD BEFORE MERGING INTO BROADER PRECIP PLUME. MODIFIED
FCST SOUNDINGS SUGGEST THIS ACTIVITY IS ROOTED AROUND 650 MB --
ABOVE SUPERFREEZING LAYER BUT WELL WITHIN RANGE WHERE SUPERCOOLED
LIQUID DROPS ARE BEING PROCESSED THROUGH AN LFC...BENEATH MUCAPE
100-200 J/KG.
..EDWARDS.. 02/04/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...HUN...MEG...JAN...LIX...LZK...LCH...SHV...
TSA...FWD...OUN...
LAT...LON 34579602 35029543 34829232 35198986 35028819 34568769
33688801 32348877 31139048 30559238 32039445 32519580
33629628 34579602SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 3, 10:36 PM CST | Mesoscale Discussion | SPC | Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 23 more | 6 hr |
Nearby
Mesoscale Discussions in Mississippi, 2011Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Louisiana, 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.