Alert archive / Florida / Mesoscale Discussions in 2016

Mesoscale Discussion 334

April 2, 2016Hernando County, Pasco County, Pinellas County, Florida

The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2016, 8:42 AM EDT for Hernando County, Pasco County, Pinellas County, Florida. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Apr 2, 2016, 8:42 AM EDT (12:42 UTC)
Expired: Apr 2, 2016, 10:15 AM EDT
In force: 93 min
Issued by: the Storm Prediction Center

Counties Hernando County, FL, Pasco County, FL, Pinellas County, FL

The radar

The Tampa radar (KTBW), 73 km from the middle of the area, began a volume at 12:41 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

Tampa Bay, FL (KTBW), launched 12:00Z, 0.7 hours before the alert went out and 73 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: 626 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 728 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 270 m²/s²
Significant tornado parameter: 0.9
Supercell composite: 4.4

Open this sounding in Storm Lab

The text

As transmitted.

513 
ACUS11 KWNS 021243
SWOMCD
SPC MCD 021242 
FLZ000-021415-

MESOSCALE DISCUSSION 0334
NWS STORM PREDICTION CENTER NORMAN OK
0742 AM CDT SAT APR 02 2016

AREAS AFFECTED...W-CNTRL FL

CONCERNING...SEVERE THUNDERSTORM WATCH 77...

VALID 021242Z - 021415Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 77
CONTINUES.

SUMMARY...A CONDITIONAL RISK FOR LOCALIZED WIND DAMAGE WILL CONTINUE
THIS MORNING ACROSS THE N-CNTRL PART OF THE FL PENINSULA.  IT
APPEARS THE RELATIVELY HIGHEST RISK WILL OCCUR NEAR THE W COAST AS
STRONGER EMBEDDED CELLS WITHIN A LARGER CONVECTIVE LINE MOVE INTO
THE IMMEDIATE COASTAL AREAS.

DISCUSSION...RADAR MOSAIC THE PAST FEW HOURS HAS SHOWN THE
TRANSITION FROM A PARALLEL STRATIFORM ORIENTATION TSTM BAND TO A
LEAD-STRATIFORM CONFIGURATION ACROSS N FL.  THIS TRANSITION HAS
LIKELY LED TO DELETERIOUS POTENTIAL FOR DAMAGING WIND GUSTS OWING IN
PART TO SATURATED LOWER TROPOSPHERIC PROFILES /I.E. POOR LAPSE
RATES/.  DESPITE THESE FACTORS LIMITING CONVECTIVE WIND
POTENTIAL...WATER VAPOR IMAGERY SHOWS AN IMPULSE MOVING ACROSS THE
NERN GULF/N FL AND SRN GA VICINITY THIS MORNING.  LARGE-SCALE
SUPPORT FOR CONVECTIVE ORGANIZATION WITH THIS DISTURBANCE WILL AT
LEAST MAINTAIN POTENTIAL FOR LOCALIZED WIND DAMAGE.  THE 12Z TBW
RAOB SHOWED STRONG EFFECTIVE SHEAR /65 KT/ AND AMPLE BUOYANCY /1000
J PER KG MUCAPE/ FOR AT LEAST LOW TSTM WIND GUST POTENTIAL THIS
MORNING.  GIVEN THE DISTINCT DIFFERENCE IN CONVECTIVE CHARACTER WITH
THE TSTM ACTIVITY OVER THE ERN GULF COMPARED TO THE LEAD-STRATIFORM
CHARACTER OF THE STORMS OVER N FL --RESPONSIBLE FOR NO DAMAGING WIND
REPORTS SO FAR-- CURRENTLY THINKING A RELATIVELY HIGHER RISK FOR
STRONG TO LOCALLY SEVERE WIND GUSTS MAY ACCOMPANY THE ACTIVITY OVER
THE W COAST NEAR AND N OF TPA DURING THE NEXT FEW HOURS AS TEMPS
SLOWLY WARM AND LOW-LEVEL LAPSE RATES GRADUALLY STEEPEN.

..SMITH.. 04/02/2016

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

ATTN...WFO...MLB...TBW...

LAT...LON   28678269 28618219 28388189 27968224 27858306 28678269

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 1, 9:02 PM EDT	Tornado Watch	SPC	Alachua, Baker, Bay, Bradford, Calhoun, Clay and 21 more	9 hr
Apr 1, 11:39 PM EDT	Mesoscale Discussion	SPC	Baker, Bradford, Columbia, Franklin, Hamilton, Jefferson and 7 more	66 min
Apr 2, 2:19 AM EDT	Mesoscale Discussion	SPC	Dixie, Gilchrist, Lafayette, Taylor	56 min
Apr 2, 4:18 AM EDT	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Citrus, Clay, Columbia and 15 more	117 min
Apr 2, 6:00 AM EDT	Severe Thunderstorm Watch	SPC	Alachua, Bradford, Citrus, Clay, Flagler, Gilchrist and 12 more	7 hr
Apr 2, 12:01 PM EDT	Mesoscale Discussion	SPC	Hernando, Lake, Orange, Pasco, Seminole, Sumter and 1 more	59 min

Nearby

Mesoscale Discussions in Florida, 2016 Every mesoscale discussion in 2016

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.