Alert archive / Florida / Mesoscale Discussions in 2014
Mesoscale Discussion 367
The Storm Prediction Center issued this mesoscale discussion at Apr 18, 2014, 7:11 PM EDT for Martin County, Palm Beach County, Saint Lucie County, Florida. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 18, 2014, 7:11 PM EDT (23:11 UTC)
- Expired
- Apr 18, 2014, 9:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
Counties Martin County, FL, Palm Beach County, FL, Saint Lucie County, FL
The radar
The Melbourne radar (KMLB), 128 km from the middle of the area, began a volume at 23:10 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, 11.2 hours before the alert went out and 129 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
- 1121 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 664 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 39 m²/s²
- 0-3 km storm-relative helicity
- 35 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
148
ACUS11 KWNS 182312
SWOMCD
SPC MCD 182311
FLZ000-190115-
MESOSCALE DISCUSSION 0367
NWS STORM PREDICTION CENTER NORMAN OK
0611 PM CDT FRI APR 18 2014
AREAS AFFECTED...PORTIONS OF SOUTHEAST FLORIDA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 182311Z - 190115Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THUNDERSTORMS APPROACHING THE ATLANTIC COAST OF SOUTHEAST
FLORIDA MAY BECOME LOCALLY SEVERE BEFORE MOVING OFFSHORE EARLY THIS
EVENING. THE ISSUANCE OF A WW IS UNLIKELY.
DISCUSSION...THUNDERSTORMS THAT DEVELOPED ALONG A N/S-ORIENTED
CONFLUENCE AXIS ANALYZED OVER INTERIOR SECTIONS OF THE PENINSULA
WILL CONTINUE TO BE STEERED TOWARD THE ATLANTIC COAST THIS EVENING
BY 40-50 KT MID-LEVEL SWLYS SAMPLED BY THE MLB VWP. THE DOWNSHEAR
ENVIRONMENT IS CHARACTERIZED BY MODERATE TO STRONG SFC-BASED
BUOYANCY...PARTLY OWING TO LOWER 80S SFC TEMPERATURES AMIDST UPPER
60S-LOWER 70S DEWPOINTS. UPDRAFTS AND DOWNDRAFTS COULD FURTHER
INTENSIFY AS THEY APPROACH THE COAST. MODERATE SHEAR CONTRIBUTED BY
THE ENHANCED MID-LEVEL FLOW MAY SUPPORT SOME PERSISTENCE AND
ORGANIZATION TO CONVECTIVE STRUCTURES. MARGINAL SUPERCELL STRUCTURES
COULD EVOLVE AS THIS ACTIVITY ENCOUNTERS RELATIVELY BACKED SELY SFC
WINDS OBSERVED ALONG THE COAST. THE RISK FOR ISOLATED DMGG
WINDS...SVR HAIL...AND POSSIBLY A TORNADO CANNOT BE RULED OUT.
HOWEVER...THIS ACTIVITY LIES WELL IN ADVANCE OF STRONGER DEEP-LAYER
FORCING FOR ASCENT IMPLIED BY WATER VAPOR IMAGERY...WHICH WILL
LIKELY BE A DETERRENT TO GREATER SVR TSTM COVERAGE.
..COHEN/MEAD.. 04/18/2014
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MFL...MLB...
LAT...LON 27078069 27648067 27728050 27588032 27228013 26558003
26228022 26218064 26428081 27078069SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 11:48 AM EDT | Mesoscale Discussion | SPC | Alachua, Charlotte, Citrus, DeSoto, Flagler, Hardee and 16 more | 117 min |
| Apr 18, 1:51 PM EDT | Severe Thunderstorm Watch | SPC | Citrus, DeSoto, Hardee, Hernando, Highlands, Hillsborough and 7 more | 4 hr |
| Apr 18, 3:57 PM EDT | Mesoscale Discussion | SPC | Highlands, Lake, Marion, Polk, Sumter | 93 min |
| Apr 18, 5:48 PM EDT | Mesoscale Discussion | SPC | Baker, Bradford, Clay, Columbia, Duval, Flagler and 6 more | 87 min |
Nearby
Mesoscale Discussions in Florida, 2014Every mesoscale discussion in 2014
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.