Alert archive / Florida / Mesoscale Discussions in 2003

Mesoscale Discussion 2152

August 14, 200314 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Aug 14, 2003, 3:29 AM EDT for 14 counties in Florida. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Aug 14, 2003, 3:29 AM EDT (07:29 UTC)
Expired: Aug 14, 2003, 6:30 AM EDT
In force: 3 hr
Issued by: the Storm Prediction Center

Counties Broward County, FL, Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hendry County, FL, Highlands County, FL, Lee County, FL, Martin County, FL, Miami-Dade County, FL, Monroe County, FL, Okeechobee County, FL, Palm Beach County, FL, Saint Lucie County, FL

The radar

The Miami radar (KAMX), 101 km from the middle of the area, began a volume at 07:29 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

Miami, FL (KMFL), launched 00:00Z, 7.5 hours before the alert went out and 111 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: 2451 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 761 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 71 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

009 
ACUS11 KWNS 140730
SWOMCD
SPC MCD 140729 
FLZ000-141030-

MESOSCALE DISCUSSION 2152
NWS STORM PREDICTION CENTER NORMAN OK
0229 AM CDT THU AUG 14 2003

AREAS AFFECTED...S FL

CONCERNING...HEAVY RAINFALL 

VALID 140729Z - 141030Z

SCATTERED-NUMEROUS CONVECTION IN CLUSTERS WILL MOVE GENERALLY WWD
ACROSS MUCH OF S FL THROUGH AT LEAST 10Z.  EXPECT RAIN RATES 1.5-2.5
INCHES/HOUR...LOCALLY TOPPING 3 INCHES/HOUR.  POTENTIAL WILL
INCREASE WITH TIME OVER SW FL AND LOWER/MIDDLE KEYS WITH APPROACH OF
LOW-MIDLEVEL TROPICAL TROUGH...WHICH AS OF 7Z REMAINS JUST OFFSHORE
ATLANTIC COAST BASED ON BACKED SFC FLOW AND PRESSURE FALLS OVER SERN
FL.  REF NHC OUTLOOK UNDER WMO HEADER ABNT20 KNHC FOR FCST GUIDANCE
REGARDING THIS SYSTEM.

THOUGH LOCALLY INTENSE RAINFALL RATES ARE LIKELY WITH TSTM
CORES...MUCH OF THIS CONVECTION WILL BE CHARACTERIZED BY SPARSE
LIGHTNING AND WARM-CLOUD PRECIP PRODUCTION PROCESSES.  INSTABILITY
SHOULD BE LOWER THAN AT 00Z...RESULTING IN LESS THAN 00Z MUCAPE OF 
2500-4000 J/KG BECAUSE OF EXTENSIVE PRECIP.  HOWEVER...1500-2500
J/KG MUCAPE STILL IS POSSIBLE BASED ON MODIFIED RUC/ETA  SOUNDINGS. 
OBSERVED RAOBS AND FCST SOUNDINGS SUGGEST VERY RICH MOISTURE
AVAILABLE WITH PW EXCEEDING 2 INCHES AND 17-18 G/KG MEAN MIXING
RATIOS.  LOW LEVEL CONVERGENCE ASSOCIATED WITH TROUGH WILL AID IN
MAINTENANCE OF RELATIVELY DENSE CONVECTIVE COVERAGE...WITH EFFICIENT
PRECIP PRODUCTION.

00Z RAOBS...VWP DATA SINCE THEN...AND MODEL FCST SOUNDINGS ALL
INDICATE LOW LEVEL FLOW AND VERTICAL SHEAR WILL REMAIN QUITE WEAK
OVER MOST OF REGION THROUGH AROUND 8-9Z.  THEREAFTER...STRONGER
GRADIENT FLOW E OF TROUGH SHOULD MOVE OVER AREA WITH INCREASING LOW
LEVEL SHEAR...AND INCREASING POTENTIAL FOR STORMS TO ROTATE.  FOR
TIME BEING...MAIN HAZARD IS HEAVY RAIN...BUT WILL CONTINUE
MONITORING SEVERE POTENTIAL.

..EDWARDS.. 08/14/2003

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

ATTN...WFO...MFL...MLB...EYW...TBW...

27058248 27688042 26788001 25508019 24748087 24458187
24558214 24718155 25068074 25188118 25568124 25828144
25878171 26348187 26478220

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 14, 7:12 AM EDT	Mesoscale Discussion	SPC	Broward, Charlotte, Collier, DeSoto, Glades, Hendry and 8 more	3 hr

Nearby

Mesoscale Discussions in Florida, 2003 Every 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.