Alert archive / Florida / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 52, NWS Melbourne, FL

July 18, 2017Orange County, Seminole County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Jul 18, 2017, 6:10 PM EDT for Orange County, Seminole County, Florida. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 18, 2017, 6:10 PM EDT (22:10 UTC)
Expired: Jul 18, 2017, 6:36 PM EDT
In force: 26 min
Issued by: NWS Melbourne, FL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Orange County, FL, Seminole County, FL

The radar

The Melbourne radar (KMLB), 82 km from the middle of the area, began a volume at 22:12 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

Cape Canaveral, FL (KXMR), launched 12:00Z, 10.2 hours before the alert went out and 78 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1007 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 952 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: -15 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

643 
WUUS52 KMLB 182210
SVRMLB
FLC095-117-182300-
/O.NEW.KMLB.SV.W.0052.170718T2210Z-170718T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Melbourne FL
610 PM EDT TUE JUL 18 2017

The National Weather Service in Melbourne has issued a

* Severe Thunderstorm Warning for...
  Southern Seminole County in east central Florida...
  North Central Orange County in east central Florida...

* Until 700 PM EDT

* At 609 PM EDT, a severe thunderstorms were located over Winter 
  Park and near the University of Central Florida, moving northeast 
  at 15 mph.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  Orlando, Apopka, Altamonte Springs, Oviedo and Winter Springs. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with these storms, and may lead to 
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2855 8114 2853 8119 2853 8133 2855 8149
      2871 8146 2877 8141 2868 8108
TIME...MOT...LOC 2209Z 227DEG 15KT 2859 8134 

HAIL...1.00IN
WIND...60MPH
 
$$

Sedlock

2 follow-up statements

594 
WWUS52 KMLB 182228
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
628 PM EDT TUE JUL 18 2017

FLC095-117-182300-
/O.CON.KMLB.SV.W.0052.000000T0000Z-170718T2300Z/
Seminole FL-Orange FL-
628 PM EDT TUE JUL 18 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR SOUTHERN SEMINOLE AND CENTRAL ORANGE COUNTIES...

At 626 PM EDT, severe thunderstorms were located over Union Park, 
Azaela Park, Aloma and near the University Of Central Florida. 
Movement was chaotic. Strong winds from this cluster of storms was 
occurring into southern Seminole County.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Portions of Orlando, Apopka, Altamonte Springs, Oviedo and Winter 
Springs. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with these storms, and may lead to 
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2855 8114 2853 8119 2853 8133 2855 8149
      2871 8146 2877 8141 2868 8108
TIME...MOT...LOC 2226Z 276DEG 20KT 2857 8122 

HAIL...1.00IN
WIND...60MPH
 
$$

Sedlock

839 
WWUS52 KMLB 182236
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
636 PM EDT TUE JUL 18 2017

FLC095-117-182245-
/O.CAN.KMLB.SV.W.0052.000000T0000Z-170718T2300Z/
Seminole FL-Orange FL-
636 PM EDT TUE JUL 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN SEMINOLE AND CENTRAL
ORANGE COUNTIES IS CANCELLED...
                
The storms which prompted the warning have weakened below severe 
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.  However gusty winds and 
heavy rain, with minor nuisance flooding, are still possible with 
these thunderstorms.

LAT...LON 2855 8114 2853 8119 2853 8133 2855 8149
      2871 8146 2877 8141 2868 8108
TIME...MOT...LOC 2234Z 227DEG 15KT 2860 8119 

$$

Sedlock

The office that day

Everything else NWS Melbourne, FL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 12:35 PM EDT	Special Weather Statement	MLB	Saint Lucie	40 min
Jul 18, 1:20 PM EDT	Special Weather Statement	MLB	Indian River, Saint Lucie	55 min
Jul 18, 2:17 PM EDT	Special Weather Statement	MLB	Brevard	43 min
Jul 18, 3:46 PM EDT	Special Marine Warning	MLB		3 hr
Jul 18, 4:26 PM EDT	Special Weather Statement	MLB	Volusia	64 min
Jul 18, 5:02 PM EDT	Special Weather Statement	MLB	Seminole	58 min
Jul 18, 5:33 PM EDT	Special Weather Statement	MLB	Orange	42 min
Jul 18, 5:41 PM EDT	Severe Thunderstorm Warning	MLB	Orange	31 min
Jul 18, 5:47 PM EDT	Areal Flood Advisory	MLB	Seminole, Volusia	88 min
Jul 18, 5:55 PM EDT	Areal Flood Advisory	MLB	Orange	95 min
Jul 18, 6:01 PM EDT	Special Weather Statement	MLB	Seminole	59 min
Jul 18, 6:22 PM EDT	Areal Flood Advisory	MLB	Orange, Seminole	83 min
Jul 18, 6:24 PM EDT	Special Weather Statement	MLB	Orange	36 min
Jul 18, 6:29 PM EDT	Areal Flood Advisory	MLB	Osceola	91 min
Jul 18, 6:49 PM EDT	Special Weather Statement	MLB	Seminole	41 min

Nearby

Severe Thunderstorm Warnings in Florida, 2017 Every severe thunderstorm warning in 2017

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.