Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 2029

October 9, 2012Monroe County, Florida

The Storm Prediction Center issued this mesoscale discussion at Oct 9, 2012, 5:59 PM EDT for Monroe County, Florida. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Oct 9, 2012, 5:59 PM EDT (21:59 UTC)
Expired
Oct 9, 2012, 7:30 PM EDT
In force
91 min
Issued by
the Storm Prediction Center

County Monroe County, FL

The radar

The Miami radar (KAMX), 74 km from the middle of the area, began a volume at 22:02 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 12:00Z, 10.0 hours before the alert went out and 86 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, Miami, FL at 12:00Z on 2012-10-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1889 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Miami, FL at 12:00Z on 2012-10-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.193958Sfc1 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
1889 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
661 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
38 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.

332 
ACUS11 KWNS 092159
SWOMCD
SPC MCD 092159 
FLZ000-092330-

MESOSCALE DISCUSSION 2029
NWS STORM PREDICTION CENTER NORMAN OK
0459 PM CDT TUE OCT 09 2012

AREAS AFFECTED...SWRN FL PENINSULA

CONCERNING...HEAVY RAINFALL 

VALID 092159Z - 092330Z

SUMMARY...CLUSTERS OF THUNDERSTORMS OVER THE SWRN FL PENINSULA MAY
PRODUCE HEAVY RAINFALL WITH RATES TO 2 IN/HR THROUGH AROUND 23Z.

DISCUSSION...ONGOING CONVECTION THAT DEVELOPED ALONG THE WEST-COAST
SEA BREEZE CIRCULATION HAS REMAINED NEARLY STATIONARY FROM SRN
COLLIER COUNTY SWD INTO MAINLAND MONROE COUNTY AND INTO FAR SWRN
MIAMI-DADE COUNTY. MIAMI VWP DATA DEPICT WEAK MEAN FLOW THROUGH THE
CLOUD LAYER...WHICH WILL CONTINUE TO SUPPORT QUASI-STATIONARY
CONVECTION. AND...AS THE EAST-COAST SEA BREEZE BOUNDARY INTERACTS
WITH THIS CONVECTION WHILE MOVING WNWWD AROUND 10 KNOTS...SOME
INTENSIFICATION IS ANTICIPATED AMIDST A MODERATELY UNSTABLE AIR
MASS. HEAVY RAINFALL WILL BE SUPPORTED BY A WARM-CLOUD LAYER AROUND
4-4.5 KM DEEP...RELATIVELY LOW LCL HEIGHTS...AND A DEEP/NARROW CAPE
PROFILE PER MODIFIED KEY WEST AND MIAMI 12Z RAOBS. AND...WITH PW
VALUES AROUND 2-2.15 INCHES PER GPS PW DATA...RAINFALL RATES TO 2
IN/HR MAY OCCUR WITH THE CONVECTION DURING THE NEXT HOUR OR SO.
PRECIPITATION LOADING PROCESSES MAY ALSO SUPPORT WET MICROBURSTS
WITH OCCASIONALLY STRONG WIND GUSTS.

..COHEN.. 10/09/2012

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

ATTN...WFO...MFL...

LAT...LON   26128106 26118106 25808090 25608090 25278079 25218090
            25308100 25438111 25638124 25768133 25908154 25988157
            26118149 26128106

Nearby

Mesoscale Discussions in Florida, 2012Every mesoscale discussion in 2012

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.