EXAMPLE 1:  SEVERE THUNDERSTORM EVENT

1900 UTC 25 April 2001

This KMLB WSR-88D reflectivity image was taken 1-hour prior to a severe thunderstorm which developed over Palm Bay (just south of the KMLB radar site). The storm produced dime size hail between 2003 and 2031 UTC (see Table 1). The corresponding image from LDIS (below) depicts relatively high buoyancy (CAPE) along the Florida east coast south of Cape Canaveral, including the area where the severe cell later developed. LDIS also indicated a sea breeze convergence boundary over the central Florida interior from west of Orlando to west of Lake Okeechobee. This boundary was erroneously displaced too far inland, likely partially due to the fact that surface METAR observations are only available from the Atlantic and Gulf coastline within South Florida. Thus, LDIS typically indicates proper initial development of the Atlantic breeze boundary near the coast, but then "jumps" the convergence zone well inland over one analysis period (15 minutes), likely due to the lack of data over the interior southern peninsula.
 
 
 
 
 
 
 
 
 
 
 
 

2000 UTC 25 April 2001

This KMLB WSR-88D reflectivity image indicates the severe thunderstorm over Palm Bay (note the small >65 dBZ reflectivity core near Palm Bay). The corresponding LDIS depiction (below) is similar to the analysis at 1900 UTC. A swath of high buoyancy remains anchored along the Atlantic coast south of Cape Canaveral, with CAPE values slightly higher near Palm Bay than an hour earlier (now near 1400 J/kg). An easterly flow is shown along the east coast, with a continued erroneous placement of the sea breeze boundary too far inland.

The depiction of the higher CAPE toward the east coast was useful for assessing the near-storm environment and potential strong to severe convection.

Note: this LDIS event occurred prior to the ingestion of KMLB WSR-88D Level II reflectivity and radial velocity data & FAWN surface observations. Improvements to the placement of synoptic and mesoscale boundaries are expected once supplemental data sets are ingested.
 
 
 
 
 
 
 
 
 
 
 

Table 1. Local Storm Report detailing the severe weather reports associated with the storm over Palm Bay.

PRELIMINARY LOCAL STORM REPORT NATIONAL WEATHER SERVICE MELBOURNE FL 453 PM EDT WED APR 25 2001   TIME (EDT) .....CITY LOCATION..... ....COUNTY LOCATION.... STATE . ...EVENT/REMARKS... . 403 PM . . PALM BAY BREVARD . FL . . 1.00 INCH HAIL PUBLIC REPORT FROM THE ST JOHNS RIVER MGMT DIST 426 PM . . PALM BAY  BREVARD . FL . . 0.75 INCH HAIL PUBLIC REPORT FROM HARRIS CORP. (PALM BAY RD AND RJ  CONLAN BLVD). 431 PM . . PALM BAY BREVARD . FL . . 0.75 INCH HAIL PUBLIC REPORT ALONG U.S. ROUTE 1 IN NORTH PALM BAY.