We knew that April 8, 1998 was going to be a bad day. An upper level low was over Iowa. Strong upper level winds were moving eastward from the southern Plains. A strong southerly flow was pumping lots of warm, moist air northward from the Gulf of Mexico. Instability levels were on the increase throughout the day. By early afternoon, CAPE values were in the 1000-1500 j/kg range over Central Alabama. Those values would rise to nearly 2500 j/kg by early evening. Once storms formed, it was evident that they would quickly become supercells, because 0-3 km helicity values were over 400 m2s2. But the situation was not completely clear cut. A large area of low cloudiness kept some areas cooler through much of the day and a hazy sun did not break out until mid afternoon.
With the instability and shear over the Deep South, the Storm Prediction Center issued a high risk severe weather outlook for the northern half of Alabama, the northern half of Mississippi and northwestern Georgia. Hazardous weather outlooks during the day indicated that there was a threat of severe weather. Severe thunderstorms were mentioned in NWS forecast products issued during the day. Tornado watches were issued by 2 p.m.
A line of thunderstorms developed from Jackson, MS to Meridian to north of Tuscaloosa at early evening. The line progressed eastward and the storms rapidly intensified. A dew point boundary was evident from southern Mississippi into North Central Alabama. A supercell thunderstorm developed along this boundary in eastern Mississippi. The supercell would cross into Alabama’s Pickens County. Meanwhile, on radar, an outflow boundary was moving north over Central Alabama.
An F3 tornado touched down just south of Gordo at 7:02 p.m. It passed into Tuscaloosa County and moved to north of Tuscaloosa and Northport before it lifted at 7:32 p.m. The mesocyclone continued ENE. A second tornado would touch down ten minutes later over extreme eastern Tuscaloosa County. It crossed into Jefferson County, becoming extremely defined on Doppler radar.
It would be on the ground for 46 minutes. The 31 mile path was up to ¾ of a mile wide. The devastating F5 twister ripped through the communities of Oak Grove, Sylvan Springs, Rock Creek, MacDonald Chapel. It was headed right for the northern sections of downtown Birmingham when it lifted near US-78.
Thirty two people died in what is the seventh deadliest tornado in Alabama history. The mesocyclone crossed the Birmingham metro area but the next tornado would not touch down until the storm was over St. Clair. Two people died there.
