Alert archive / Florida / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 100, NWS Melbourne, FL
NWS Melbourne, FL issued this severe thunderstorm warning at Jul 12, 1999, 5:12 PM EDT for Indian River County, Okeechobee County, Florida. It was in force for 48 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Jul 12, 1999, 5:12 PM EDT (21:12 UTC)
- Expired
- Jul 12, 1999, 6:00 PM EDT
- In force
- 48 min
- Issued by
- NWS Melbourne, FL
- Area
- Whole counties
Counties Indian River County, FL, Okeechobee County, FL
The radar
The Melbourne radar (KMLB), 64 km from the middle of the area, began a volume at 21:11 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 12, 5:17 PM EDT | Hail 0.75 | Basinger, FL | |
| Jul 12, 5:32 PM EDT | Hail 0.75 | Ft Drum, FL |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Tampa Bay, FL (KTBW), launched 12:00Z, 9.2 hours before the alert went out and 166 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
- 1027 J/kg
- Mixed-layer CIN
- -48 J/kg
- Mixed-layer LCL
- 1022 m above ground
- 0-6 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- -7 m²/s²
- 0-3 km storm-relative helicity
- 28 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Melbourne, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 12, 2:45 PM EDT, 2 hours 27 minutes earlier.
Area forecast discussion, Jul 12, 2:45 PM EDT, 2 hours 27 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 245 PM EDT MON JUL 12 1999 E TO W FRONTAL TROUGH OVER THE SE STATES WAS SINKING SLOWLY SWD. WLY WINDS SOUTH OF THIS TROUGH WERE INCREASING OVER N FL...INHIBITING ECSB DEVELOPMENT FROM VOLUSIA COUNTY NORTH...HOWEVER THE ACTIVE WEST COAST SEA BREEZE BOUNDARY WAS ALREADY CROSSING INTO LAKE COUNTY. STORM ACTIVITY WILL INCREASE WITH A MERGER THIS AFTERNOON OVER CENTRAL FL. RANDOM SHOWERS AND STORMS FROM ORLANDO AND THE CAPE SOUTH SHOULD INCREASE IN COVERAGE AS THE EAST COAST BREEZE MOVES INLAND. TONIGHT...EWD MOVING STORMS AND SHOWERS WILL CROSS THE BEACHES AND COASTAL WATERS FROM THE CAPE N AS ACTIVITY DIMINISHES RAPIDLY WITH NIGHTFALL. RIDGE AXIS SINKS A LITTLE SOUTH WITH LIGHT WIND AND PARTLY CLOUDY SKIES. TUESDAY-WEDNESDAY NIGHT...BROAD LOW-MID LEVEL RIDGE OVER CENTRAL FLORIDA WILL SINK TO SOUTHERNMOST CWA. SQUEEZE PLAY WILL BE ON AS SHORT WAVE AND ASSOCIATED SURFACE TROUGH STALL OVER THE SE STATES AND WEAK INVERTED TROUGH CROSSES EXTREME S FL WED. BOTH DISTURBANCES WILL TEND TO INCREASE MOISTURE LEVELS OVER THE PENINSULA...WITH DEEPEST MOISTURE LIKELY REMAINING OVER THE NORTHERN THIRD. WESTERLY STEERING REGIME...ALBEIT WEAK...WILL FAVOR INLAND CONVECTION DURING AFTERNOON AND EAST COAST CONVECTION LATE IN THE DAY. WILL INDICATE 50/40 POPS N/S TUE AND 50 ALL AREAS WED. MAX TEMPS WILL CONTINUE NEAR CLIMO INLAND AND A CATEGORY ABOVE ALONG COAST. THURSDAY-SATURDAY...BROAD RIDGE BECOMES RE-ESTABLISHED N OF CWA...ALLOWING RETURN TO DEEP E/SE FLOW OVER ENTIRE CWA. AT THIS POINT...BOUNDARY LAYER FLOW DOES NOT LOOK STRONG ENOUGH TO WARRANT NOCTURNAL RAIN CHANCES ALONG THE COAST. WILL CONTINUE EARLIER TREND OF MORNING/EARLY AFTERNOON STORMS EAST SIDE...AND AFTERNOON/EARLY EVENING CONVECTION INTERIOR. TEMPS NEAR CLIMO. MARINE...NO HIGHLIGHTS. WEAK SYNOPTIC SCALE S/SW FLOW WILL ALLOW FOR FORMATION OF AFTERNOON SEA BREEZES. SCATTERED CONVECTION OVER THE PENINSULA WILL MOVE OFFSHORE LATE AFTERNOON-EARLY EVENING HOURS. DAB BB 072/090 072/090 072 65353 MCO BB 074/093 073/092 073 65253 MLB BB 072/090 072/089 072 65253 .MLB...NONE. PENDERGRAST/SPRATT
In the hours before
Special weather statement, Jul 12, 11:18 AM EDT, 5 hours 54 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-121800- EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MELBOURNE FL 1118 AM EDT MON JUL 12 1999 ...A FEW STRONG LIGHTNING STORMS POSSIBLE THIS AFTERNOON... THE EAST COAST SEA BREEZE WILL BEGIN TO MOVE INLAND BY NOON WITH A FEW SHOWERS AND LIGHTNING STORMS STORMS DEVELOPING ALONG IT MAINLY FROM JUPITER TO NEAR MELBOURNE. THE GREATEST COVERAGE OF SHOWERS AND STORMS IS EXPECTED DURING THE LATE AFTERNOON INTO THE EARLY EVENING AS EAST AND WEST COAST BOUNDARIES COLLIDE FROM INTERIOR VOLUSIA COUNTY AND NORTHERN LAKE COUNTIES TO SEMINOLE AND ORANGE COUNTY. FROM ORLANDO NORTH...DEVELOPING STORMS WILL MOVE EAST AT 10 TO 15 MPH. STORMS SOUTH OF ORLANDO WILL BE NEARLY STATIONARY...ALLOWING FOR LOCALLY HEAVY RAIN. ALL STORMS WILL BE CAPABLE OF DEADLY LIGHTNING. ALSO...THE STRONGER STORMS OVER CENTRAL FLORIDA MAY PRODUCE SMALL HAIL...GUSTY WINDS TO 45 MPH AND UP TO TWO INCHES OF RAIN. MOVE INDOORS AT THE FIRST SIGN OF THREATENING SKIES...SINCE LIGHTNING CAN STRIKE WELL IN ADVANCE OF THE RAINFALL AREA. MARINE...A FEW LIGHTNING STORMS SHOULD PUSH SLOWLY EAST ACROSS THE INTRACOASTAL AND NEARSHORE ATLANTIC WATERS MAINLY NORTH OF CAPE CANAVERAL DURING THE LATE AFTERNOON AND EARLY EVENING. PENDERGRAST
Special weather statement, Jul 12, 11:18 AM EDT, 5 hours 54 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-121800- EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MELBOURNE FL 1118 AM EDT MON JUL 12 1999 ...A FEW STRONG LIGHTNING STORMS POSSIBLE THIS AFTERNOON... THE EAST COAST SEA BREEZE WILL BEGIN TO MOVE INLAND BY NOON WITH A FEW SHOWERS AND LIGHTNING STORMS STORMS DEVELOPING ALONG IT MAINLY FROM JUPITER TO NEAR MELBOURNE. THE GREATEST COVERAGE OF SHOWERS AND STORMS IS EXPECTED DURING THE LATE AFTERNOON INTO THE EARLY EVENING AS EAST AND WEST COAST BOUNDARIES COLLIDE FROM INTERIOR VOLUSIA COUNTY AND NORTHERN LAKE COUNTIES TO SEMINOLE AND ORANGE COUNTY. FROM ORLANDO NORTH...DEVELOPING STORMS WILL MOVE EAST AT 10 TO 15 MPH. STORMS SOUTH OF ORLANDO WILL BE NEARLY STATIONARY...ALLOWING FOR LOCALLY HEAVY RAIN. ALL STORMS WILL BE CAPABLE OF DEADLY LIGHTNING. ALSO...THE STRONGER STORMS OVER CENTRAL FLORIDA MAY PRODUCE SMALL HAIL...GUSTY WINDS TO 45 MPH AND UP TO TWO INCHES OF RAIN. MOVE INDOORS AT THE FIRST SIGN OF THREATENING SKIES...SINCE LIGHTNING CAN STRIKE WELL IN ADVANCE OF THE RAINFALL AREA. MARINE...A FEW LIGHTNING STORMS SHOULD PUSH SLOWLY EAST ACROSS THE INTRACOASTAL AND NEARSHORE ATLANTIC WATERS MAINLY NORTH OF CAPE CANAVERAL DURING THE LATE AFTERNOON AND EARLY EVENING. PENDERGRAST
The office that day
Everything else NWS Melbourne, FL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 4:24 PM EDT | Severe Thunderstorm Warning | MLB | Osceola | 46 min |
Nearby
Severe Thunderstorm Warnings in Florida, 1999Every severe thunderstorm warning in 1999
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.