Alert archive / Florida / Mesoscale Discussions in 2003

Mesoscale Discussion 340

March 27, 200345 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Mar 27, 2003, 10:27 AM EST for 45 counties in Florida. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Mar 27, 2003, 10:27 AM EST (15:27 UTC)
Expired
Mar 27, 2003, 12:30 PM EST
In force
2 hr
Issued by
the Storm Prediction Center
All 45 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Brevard County, FL, Broward County, FL, Charlotte County, FL, Citrus County, FL, Clay County, FL, Collier County, FL, Columbia County, FL, DeSoto County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Glades County, FL, Hardee County, FL, Hendry County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lafayette County, FL, Lake County, FL, Lee County, FL, Levy County, FL, Manatee County, FL, Marion County, FL, Martin County, FL, Monroe County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Palm Beach County, FL, Pasco County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Saint Lucie County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Suwannee County, FL, Union County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 68 km from the middle of the area, began a volume at 15:27 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 3.5 hours before the alert went out and 68 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-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 2003-03-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 845 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2003-03-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 166 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
845 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
820 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
166 m²/s²
0-3 km storm-relative helicity
216 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

157 
ACUS11 KWNS 271528
SWOMCD
SPC MCD 271527 
FLZ000-GAZ000-271730-

MESOSCALE DISCUSSION 0340
NWS STORM PREDICTION CENTER NORMAN OK
0927 AM CST THU MAR 27 2003

AREAS AFFECTED...FL

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 271527Z - 271730Z

SCATTERED CONVECTION WILL GRADUALLY DEVELOP ACROSS FL THROUGH
17Z. AS CELLS ORGANIZE...THE THREAT FOR HAIL..DAMAGING WIND OR AN
ISOLATED TORNADO WILL INCREASE. A WEATHER WATCH MAY BE NECESSARY
FOR PORTIONS OF CNTRL AND NRN FL LATER THIS MORNING.



MOISTURE ADVECTION OVERNIGHT HAS TRANSPORTED DEWPOINTS INTO THE
MID TO UPPER 60S ACROSS THE FL PENINSULA PRODUCING MLCAPES TO
1500 J/KG. CONVECTION HAS DEVELOPED ALONG THE AXIS OF INSTABILITY
EXISTING ACROSS THE NERN GULF OF MEXICO AND NRN FL. AS SURFACE
TEMPERATURES HEAT INTO THE LOW 80S...THE ATMOSPHERE WILL FURTHER
DESTABILIZE CAUSING CONVECTIVE DEVELOPMENT OVER LAND. THE
MID/UPR-LEVEL JET ACROSS SRN FL HAS INCREASED DEEP LAYER SHEAR
ACROSS THE PENINSULA ENOUGH FOR ISOLATED SUPERCELL DEVELOPMENT. 
THE EXPECTED ACTIVITY WILL BE PRIMARILY HAIL WITH ISOLATED WIND
DAMAGE/BRIEF TORNADO. MOST FAVORABLE AREAS WILL BE VICINITY SEA
BREEZE/OUTFLOW BOUNDARIES. AREA IS BEING MONITORED AND A WW MAY
BE REQUIRED BY 17Z .	

..BROYLES.. 03/27/2003

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...MFL...MLB...TBW...JAX...TAE...

29498333 30208345 30568237 30308141 27788048 27368033
26068008 25208094 26388190 27068243 27778274 28998314
29498333

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 27, 11:00 AM ESTSevere Thunderstorm WatchSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 34 more6 hr
Mar 27, 1:36 PM ESTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 38 more84 min
Mar 27, 2:15 PM ESTTornado WatchSPCBroward, Collier, Hendry, Miami-Dade, Monroe, Palm Beach5 hr
Mar 27, 4:10 PM ESTMesoscale DiscussionSPCBroward, Collier, Hendry, Miami-Dade, Monroe, Palm Beach95 min

Nearby

Mesoscale Discussions in Florida, 2003Every mesoscale discussion in 2003

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.