Alert archive / Florida / Flash Flood Warnings in 2017

Flash Flood Warning 21, NWS Jacksonville, FL

September 11, 20174 counties in Florida

NWS Jacksonville, FL issued this flash flood warning at Sep 11, 2017, 12:19 PM EDT for 4 counties in Florida. It was in force for 6 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 11, 2017, 12:19 PM EDT (16:19 UTC)
Expired
Sep 11, 2017, 6:15 PM EDT
In force
6 hr
Issued by
NWS Jacksonville, FL
Area
Storm-based polygon
Emergency
Flash flood emergency
Flood severity
None

Counties Clay County, FL, Duval County, FL, Putnam County, FL, Saint Johns County, FL

The radar

The Jacksonville radar (KJAX), 95 km from the middle of the area, began a volume at 16:20 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.

What was reported inside it

TimeReportWhereRemark
Sep 11, 2:58 PM EDTFLASH FLOOD2 Ssw Switzerland, FLMULTIPLE SWIFT WATER RESCUES EXECUTED BY LAW ENFORCEMENT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 4.3 hours before the alert went out and 226 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 2017-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2017-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -17 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3742 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

846 
WGUS52 KJAX 111619
FFWJAX
FLC019-031-107-109-112215-
/O.NEW.KJAX.FF.W.0021.170911T1619Z-170911T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Jacksonville FL
1219 PM EDT MON SEP 11 2017

...FLASH FLOOD EMERGENCY FOR ST. JOHNS RIVER BASIN FROM DOWNTOWN 
JACKSONVILLE SOUTHWARD THROUGH PUTNAM COUNTY...

The National Weather Service in Jacksonville has issued a

* Flash Flood Warning for...
  Western St. Johns County in northeastern Florida...
  Eastern Putnam County in northeastern Florida...
  Northeastern Clay County in northeastern Florida...
  South central Duval County in northeastern Florida...

* Until 615 PM EDT Monday

* At 1213 PM EDT, emergency management reported flash flooding, 
  including water rescues on the St. Johns River and its tributaries.

This is a FLASH FLOOD EMERGENCY for the St. Johns River basin from 
Downtown Jacksonville southward through Putnam County.

This is a PARTICULARLY DANGEROUS SITUATION. Go to the highest point 
in your house if a single story, or on the second story if possible. 
DO NOT GO INTO FLOOD WATERS as there may be electric current in the 
water. Water will continue to rise until around 2 pm in Downtown 
Jacksonville and will continue through the afternoon hours as the 
tide moves southward through the St. Johns River basin. Water levels 
may reach 4 to 6 ft above ground level on the immediate banks of the 
St. Johns and 2 to 4 ft elsewhere. 

* Some locations that will experience flooding include...
  Jacksonville, Palatka, Orange Park, Green Cove Springs, Pomona
  Park, Hastings, East Palatka, Mandarin, Fruit Cove and Ortega.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to the highest point in your house or at least the second 
story, if possible. This is an extremely dangerous and life-
threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

&&

LAT...LON 2950 8161 2935 8156 2932 8168 2934 8168
      2934 8166 2936 8166 2937 8171 2953 8180
      2977 8167 3005 8174 3030 8173 3035 8164
      2975 8145

$$

ARB
1 follow-up statement
485 
WGUS72 KJAX 112211
FFSJAX

Flash Flood Statement
National Weather Service Jacksonville FL
611 PM EDT MON SEP 11 2017

FLC019-031-107-109-112215-
/O.EXP.KJAX.FF.W.0021.000000T0000Z-170911T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
St. Johns FL-Putnam FL-Clay FL-Duval FL-
611 PM EDT MON SEP 11 2017

...THE FLASH FLOOD WARNING FOR WESTERN ST. JOHNS...EASTERN PUTNAM...
NORTHEASTERN CLAY AND SOUTH CENTRAL DUVAL COUNTIES WILL EXPIRE AT 615
PM EDT...

The storm surge flooding along the St. Johns River has not ended. 
Water levels will remain high for the next couple of days. Further 
details can be found in the Coastal Flood Warning which has been 
issued for the affected area.

LAT...LON 2950 8161 2935 8156 2932 8168 2934 8168
      2934 8166 2936 8166 2937 8171 2953 8180
      2977 8167 3005 8174 3030 8173 3035 8164
      2975 8145

$$

ARB

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 8:06 PM EDTAreal Flood WarningJAXDuval, Nassau, Saint Johns3 hr
Sep 10, 8:09 PM EDTAreal Flood WarningJAXClay, Duval, Flagler, Putnam, Saint Johns3 hr
Sep 10, 8:10 PM EDTTornado WarningJAXFlagler, Saint Johns35 min
Sep 10, 8:38 PM EDTAreal Flood WarningJAXAlachua, Baker, Bradford, Clay, Duval, Putnam and 2 more3 hr
Sep 10, 8:44 PM EDTAreal Flood WarningJAXDuval, Nassau3 hr
Sep 10, 10:23 PM EDTFlash Flood WarningJAXDuval, Nassau3 hr
Sep 10, 10:56 PM EDTAreal Flood WarningJAXClay, Duval, Nassau, Saint Johns6 hr
Sep 11, 12:26 AM EDTAreal Flood WarningJAXAlachua, Bradford, Clay, Flagler, Marion, Putnam and 1 more3 hr
Sep 11, 12:38 AM EDTAreal Flood WarningJAXNassau6 hr
Sep 11, 12:49 AM EDTFlash Flood WarningJAXFlagler, Marion, Putnam, Saint Johns5 hr
Sep 11, 1:35 AM EDTFlash Flood WarningJAXClay, Flagler, Putnam, Saint Johns3 hr
Sep 11, 2:02 AM EDTTornado WarningJAXNassau28 min
Sep 11, 2:10 AM EDTFlash Flood WarningJAXClay, Saint Johns3 hr
Sep 11, 2:31 AM EDTFlash Flood WarningJAXClay, Duval, Nassau, Saint Johns3 hr
Sep 11, 2:34 AM EDTTornado WarningJAXNassau6 min
Sep 11, 2:41 AM EDTFlash Flood WarningJAXClay, Duval, Saint Johns3 hr
Sep 11, 3:36 AM EDTTornado WarningJAXDuval24 min
Sep 11, 4:10 AM EDTFlash Flood WarningJAXDuval, Nassau3 hr
Sep 11, 4:22 AM EDTAreal Flood AdvisoryJAXMarion3 hr
Sep 11, 4:38 AM EDTAreal Flood AdvisoryJAXAlachua, Bradford, Clay, Putnam3 hr
Sep 11, 5:08 AM EDTAreal Flood WarningJAXAlachua, Baker, Bradford, Columbia, Gilchrist, Union3 hr
Sep 11, 5:14 AM EDTFlash Flood WarningJAXNassau3 hr
Sep 11, 5:34 AM EDTFlash Flood WarningJAXClay, Duval, Nassau, Saint Johns3 hr
Sep 11, 6:15 AM EDTFlash Flood WarningJAXBaker, Bradford, Clay, Columbia, Duval, Union3 hr
Sep 11, 6:37 AM EDTAreal Flood WarningJAXColumbia, Hamilton, Suwannee3 hr
Sep 11, 6:45 AM EDTFlash Flood Warning EmergencyJAXDuval6 hr
Sep 11, 8:23 AM EDTAreal Flood WarningJAXClay, Duval, Nassau, Saint Johns3 hr
Sep 11, 9:06 AM EDTAreal Flood WarningJAXBaker, Bradford, Clay, Columbia, Duval, Union3 hr
Sep 11, 9:48 AM EDTRiver Flood WarningJAXColumbia, Gilchrist, Suwannee18 days
Sep 11, 5:11 PM EDTWind AdvisoryJAXBaker, Bradford, Duval, Flagler, Gilchrist, Nassau and 2 more5 hr
Sep 11, 5:18 PM EDTCoastal Flood WarningJAXDuval, Flagler, Nassau3 days
Sep 11, 5:18 PM EDTRip Current StatementJAXDuval, Flagler, Nassau27 hr
Sep 11, 5:18 PM EDTHigh Surf AdvisoryJAXDuval, Flagler, Nassau10 hr
Sep 11, 5:26 PM EDTSmall Craft AdvisoryJAX28 hr

Nearby

Flash Flood Warnings in Florida, 2017Every flash flood warning in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.