Severe Weather on November 16th, 2011 

Event Summary for Central Alabama

On Tuesday, November 15th, moisture began streaming northward from the Gulf of Mexico. The moisture surge was just ahead of an approaching upper level low.  Surface dew points climbed into the middle 60s and created increased atmospheric instability late Tuesday night.  As the upper low approached, deep layer shear increased and led to increased storm relative helicities (SRH) in the lowest levels of the atmosphere. This set the stage for supercell development in Central Alabama.  By 5 am Wednesday morning, dew points had increased into the upper 60s and 0-1km SRH of 300-400 m2/s2 across Sumter and Marengo Counties.  By 745 am, one supercell dropped 2 tornadoes in these counties.  Similiar severe weather parameters advected across Central Alabama through the morning hours and caused additional  supercell development near Montgomery, Auburn and Opelika.  The information below is the PRELIMINARY (subject to change) summaries of the tornadoes from this day:

Location/Clickable Detailed Summary Link
Damage Rating/Estimated Maximum Wind Speeds
Damage Path Length/Width
Starting Point/Time
Ending Point/Time
120 mph
1 Injury
1.5 miles
600 yards
707 am
32.3763/-88.0689   709 am
85 mph
2.75 miles
250 yards
732 am
736 am
90 mph
0.88 miles
75 yards
1108 am
1110 am
110 mph
EF-2 in Georgia
2 Injuries
33.39 miles
700 yards
1152 am
1235 pm

Pertinent Geographic Information Systems (GIS) Data from this Event

Preliminary Local Storm Reports

Severe Weather Episode Data 

Surface analysis 3 am
Surface Analysis
Nov 16 3 am
Surface Analysis 6 am
Surface Analysis
  Nov 16 6 am
Sfc Analysis 9 am
Surface Analysis
Nov 16 9 am
Surface Analysis 12 pm
Surface Analysis
Nov 16 12 pm
Day 1 Outlook 6 am
Day 1 Severe Weather Outlook
Issued Nov 16 at Midnight
Day 1 Outlook 7 am
Day 1 Severe Weather Outlook
Issued Nov 16 at 7 am
Storm Reports
Storm Reports 11/15/11
Storm Reports
Storm Reports 11/16/11
06z sounding from BMX
12am Upper Air Sounding from BMX on Nov 16
12z Sounding from BMX
6am Upper Air Sounding from BMX on Nov 16 is the U.S. government's official web portal to all federal, state and local government web resources and services.