Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 25, NWS Tampa Bay, FL

May 18, 2020Hillsborough County, Manatee County, Pinellas County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at May 18, 2020, 8:34 AM EDT for Hillsborough County, Manatee County, Pinellas County, Florida. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 18, 2020, 8:34 AM EDT (12:34 UTC)
Expired
May 18, 2020, 9:00 AM EDT
In force
26 min
Issued by
NWS Tampa Bay, FL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Hillsborough County, FL, Manatee County, FL, Pinellas County, FL

The radar

The Tampa radar (KTBW), 10 km from the middle of the area, began a volume at 12:33 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, 0.6 hours before the alert went out and 10 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 2020-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 647 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 2020-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 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
647 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
743 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
-20 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-0.5

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tampa Bay, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at May 18, 3:14 AM EDT, 5 hours 20 minutes earlier.

Area forecast discussion, May 18, 3:14 AM EDT, 5 hours 20 minutes before
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Hazardous weather outlook, May 18, 5:44 AM EDT, 2 hours 50 minutes before
Hazardous Weather Outlook
National Weather Service Tampa Bay Ruskin FL
544 AM EDT Mon May 18 2020

FLZ043-050-052-056-057-061-139-142-148-149-151-155-160-162-165-
239-242-248-249-251-255-260-262-265-182145-
Sumter-Pinellas-Polk-Hardee-Highlands-DeSoto-Coastal Levy-
Coastal Citrus-Coastal Hernando-Coastal Pasco-
Coastal Hillsborough-Coastal Manatee-Coastal Sarasota-
Coastal Charlotte-Coastal Lee-Inland Levy-Inland Citrus-
Inland Hernando-Inland Pasco-Inland Hillsborough-Inland Manatee-
Inland Sarasota-Inland Charlotte-Inland Lee-
544 AM EDT Mon May 18 2020

This Hazardous Weather Outlook is for West Central And Southwest
Florida.

.DAY ONE...Today and Tonight.

...THUNDERSTORM IMPACT...
Numerous thunderstorms are expected throughout the day today.
During the late morning through the afternoon and evening, there
is potential for some strong to severe storms capable of
producing strong gusty winds, small hail, locally heavy rains,
and frequent deadly lightning strikes.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

No significant hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

Fleming

In the hours before

Special weather statement, May 18, 8:29 AM EDT, 5 minutes before
Special Weather Statement
National Weather Service Tampa Bay Area Ruskin FL
829 AM EDT Mon May 18 2020

FLZ050-151-181315-
Coastal Hillsborough FL-Pinellas FL-
829 AM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN PINELLAS AND
NORTHWESTERN HILLSBOROUGH COUNTIES UNTIL 915 AM EDT...

At 829 AM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from 11 miles west of Palm Harbor to 8 miles
southwest of Harbor Bluffs. Movement was northeast at 25 mph.

Winds in excess of 40 mph will be possible with these storms.

Locations impacted include...
Tampa, Clearwater, Largo, Pinellas Park, Palm Harbor, South
Highpoint, East Lake, Harbor Bluffs, Feather Sound, Ridgecrest,
Keystone, Safety Harbor, Oldsmar, Belleair, Belleair Bluffs, Belleair
Beach, Indian Shores, Belleair Shore, Walsingham Park and Highpoint.

LAT...LON 2810 8288 2817 8264 2816 8262 2810 8259
      2793 8260 2783 8290 2787 8291
TIME...MOT...LOC 1229Z 234DEG 21KT 2805 8294 2785 8295

TBW

The office that day

Everything else NWS Tampa Bay, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 18, 6:25 AM EDTSpecial Marine WarningTBW65 min
May 18, 7:23 AM EDTSpecial Marine WarningTBW67 min
May 18, 8:05 AM EDTSpecial Marine WarningTBW55 min
May 18, 8:29 AM EDTSpecial Weather StatementTBWPinellas46 min
May 18, 8:46 AM EDTTornado WarningTBWPinellas14 min
May 18, 8:53 AM EDTSevere Thunderstorm WarningTBWHillsborough, Manatee, Pinellas37 min
May 18, 9:00 AM EDTSpecial Marine WarningTBW30 min
May 18, 9:12 AM EDTSpecial Marine WarningTBW33 min
May 18, 9:15 AM EDTSpecial Weather StatementTBWLee45 min
May 18, 9:23 AM EDTSevere Thunderstorm WarningTBWHillsborough, Pasco, Polk37 min
May 18, 9:41 AM EDTSpecial Weather StatementTBWPolk34 min
May 18, 10:15 AM EDTSpecial Weather StatementTBWPolk45 min
May 18, 11:23 AM EDTSpecial Weather StatementTBWCharlotte112 min

Nearby

Severe Thunderstorm Warnings in Florida, 2020Every severe thunderstorm warning in 2020

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.