Alert archive / Oklahoma / Flash Flood Warnings in 2017

Flash Flood Warning 45, NWS Norman, OK

May 20, 20174 counties in Oklahoma

NWS Norman, OK issued this flash flood warning at May 20, 2017, 12:29 AM CDT for 4 counties in Oklahoma. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 20, 2017, 12:29 AM CDT (05:29 UTC)
Expired: May 20, 2017, 3:30 AM CDT
In force: 3 hr
Issued by: NWS Norman, OK
Area: Storm-based polygon
Flood severity: None

Counties Bryan County, OK, Carter County, OK, Johnston County, OK, Marshall County, OK

The radar

The Norman radar (KTLX), 141 km from the middle of the area, began a volume at 05:32 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 5.5 hours before the alert went out and 158 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: 1629 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 1516 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 189 m²/s²
0-3 km storm-relative helicity: 338 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 20.6

Open this sounding in Storm Lab

The text

As transmitted.

302 
WGUS54 KOUN 200529
FFWOUN
OKC013-019-069-095-200830-
/O.NEW.KOUN.FF.W.0045.170520T0529Z-170520T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Norman OK
1229 AM CDT SAT MAY 20 2017

The National Weather Service in Norman has issued a

* Flash Flood Warning for...
  Southwestern Johnston County in southeastern Oklahoma...
  Northwestern Bryan County in southeastern Oklahoma...
  East central Carter County in southern Oklahoma...
  Northeastern Marshall County in southeastern Oklahoma...

* Until 330 AM CDT
  
* At 1228 AM CDT, a few showers continue over the area, but runoff 
  from very heavy rainfall from storms Friday night will continue to 
  cause extensive flash flooding over the area.

* Some locations that will experience flooding include...
  Madill, Tishomingo, Dickson, Mannsville, Ravia, Milburn, Gene
  Autry, Russett, Little City and Oakland.

LAT...LON 3411 9650 3401 9655 3401 9664 3426 9713
      3430 9694 3430 9658

$$

..speg.

What forecasters said that day

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

NWS Norman, OK wrote its last area forecast discussion before this flash flood warning went out at May 19, 6:54 PM CDT, 5 hours 35 minutes earlier.

Area forecast discussion, May 19, 6:54 PM CDT, 5 hours 35 minutes before

Area Forecast Discussion
National Weather Service Norman OK
654 PM CDT Fri May 19 2017

.AVIATION...
Strong to severe thunderstorms will continue across
western north Texas and southern Oklahoma through
at least the evening hours. Thunderstorms will mainly
impact LAW and SPS with IFR conditions possible in and
around thunderstorms.

A cold front over western Oklahoma will bring a wind shift to all
TAF sites by 6Z. Mainly VFR conditions are expected after 6-9Z at
all sites.

&&

.PREV DISCUSSION... /issued 319 PM CDT Fri May 19 2017/

DISCUSSION...
Strong to severe thunderstorms continue to develop across mainly
western north Texas this afternoon. Other widely scattered
showers and a few storms are developing mainly north of a cold
front in northwest Oklahoma. Anvil debris and other light
showers are keeping parts of central and southern Oklahoma
relatively cool this afternoon.

Part of an outflow boundary that pushed well into north Texas has
been lifting slowly northward this afternoon. This boundary may
lift slowly into far southern Oklahoma later this afternoon,
however, western north Texas convection may keep this boundary
just south of the Red River.

Overall the risk of strong to severe storms will continue into
the evening, perhaps overnight, before a cold front sweeps across
southern Oklahoma by early Saturday morning.

Will continue the current Flood Watch through early Saturday
morning. It does appear that western north Texas and southern
Oklahoma will have the best opportunity for widespread showers
and thunderstorms through late this evening/early Saturday
morning.

Overall most of the weekend will be dry with below average
temperatures.

Another trough will approach the southern Plains around Monday of
next week. This will bring another opportunity for showers and
thunderstorms, especially across southern Oklahoma and western
north Texas.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  55  70  49  76 /  60  10   0   0
Hobart OK         51  72  48  78 /  40   0   0   0
Wichita Falls TX  57  74  51  81 /  80  10   0   0
Gage OK           46  67  46  77 /  20   0   0  10
Ponca City OK     53  67  45  75 /  50  10   0   0
Durant OK         65  75  53  80 /  90  50  10   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Saturday morning for OKZ006>008-011>013-
     017>020-023>032-037>048-050>052.

TX...Flood Watch through Saturday morning for TXZ085-086-088>090.

&&

Hazardous weather outlook, May 19, 9:10 PM CDT, 3 hours 19 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
910 PM CDT Fri May 19 2017

OKZ004>048-050>052-TXZ083>090-201100-
Harper-Woods-Alfalfa-Grant-Kay-Ellis-Woodward-Major-Garfield-
Noble-Roger Mills-Dewey-Custer-Blaine-Kingfisher-Logan-Payne-
Beckham-Washita-Caddo-Canadian-Oklahoma-Lincoln-Grady-McClain-
Cleveland-Pottawatomie-Seminole-Hughes-Harmon-Greer-Kiowa-Jackson-
Tillman-Comanche-Stephens-Garvin-Murray-Pontotoc-Coal-Cotton-
Jefferson-Carter-Johnston-Atoka-Love-Marshall-Bryan-Hardeman-
Foard-Wilbarger-Wichita-Knox-Baylor-Archer-Clay-
910 PM CDT Fri May 19 2017

This hazardous weather outlook is for portions of northern...
western...central...and southern Oklahoma...and western north
Texas.

.DAY ONE...Through tonight...

.THUNDERSTORMS...
There is a slight risk of severe thunderstorms through early
Saturday morning.

LOCATION...
The slight risk area is generally along and southeast of a line
from Shawnee to Duncan and Wichita Falls.

TIMING...
Through 2 am Saturday.

IMPACTS...
Hail up to the size of golf balls, winds to 80 mph will be
possible with the strongest storms, with the highest chances in
the slight risk area.

A few tornadoes are possible across southeast Oklahoma.

Very heavy rainfall will also result in flash flooding across
south central and southeast Oklahoma.

DISCUSSION...
Numerous showers and thunderstorms will continue to move across
south central and southeast Oklahoma and part of western north
Texas through early Saturday morning. A cold front will move
across the area overnight, ending the risk of severe
thunderstorms.

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...
Storm spotter groups and emergency management personnel should be
available for severe weather operations.

.Flooding...
Widespread heavy rainfall will be possible through tonight,
especially across south central and southeast Oklahoma.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday...

.THUNDERSTORMS...
Isolated thunderstorms will be possible in southeastern Oklahoma
Saturday morning before moving out of the area.

There will be chances of thunderstorms again Sunday night through
Tuesday.

Get graphics and more details at weather.gov/norman...and follow
our weather forecast office on Twitter and Facebook.

In the hours before

Local storm report, May 19, 11:28 PM CDT, 1 hour 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1128 PM CDT FRI MAY 19 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1127 PM     HAIL             CLARITA                 34.49N 96.44W
05/19/2017  E1.00 INCH       COAL               OK   EMERGENCY MNGR

&&

MAD

Local storm report, May 19, 11:45 PM CDT, 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1145 PM CDT FRI MAY 19 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1140 PM     FLASH FLOOD      CLARITA                 34.48N 96.43W
05/19/2017                   COAL               OK   EMERGENCY MNGR

            WATER FLOWING OVER COUNTY ROAD 1750.

&&

TLINDLEY

Local storm report, May 19, 11:47 PM CDT, 42 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1147 PM CDT FRI MAY 19 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1140 PM     FLASH FLOOD      1 ESE CLARITA           34.48N 96.42W
05/19/2017                   COAL               OK   EMERGENCY MNGR

            COUNTY ROAD 1750 NEAR CLARITA FLOODED.

&&

MAD

Local storm report, May 19, 11:50 PM CDT, 39 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1150 PM CDT FRI MAY 19 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1147 PM     HAIL             2 SW CLARITA            34.47N 96.46W
05/19/2017  E0.75 INCH       COAL               OK   TRAINED SPOTTER

&&

MAD

Local storm report, May 20, 12:14 AM CDT, 15 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1214 AM CDT SAT MAY 20 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1057 PM     FLASH FLOOD      ADA                     34.77N 96.68W
05/19/2017                   PONTOTOC           OK   EMERGENCY MNGR

            PICKUP TRUCK STALLED IN FLOOD WATERS.

&&

TLINDLEY

Local storm report, May 20, 12:20 AM CDT, 9 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
1220 AM CDT SAT MAY 20 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1216 AM     FLASH FLOOD      PONTOTOC                34.49N 96.63W
05/20/2017                   JOHNSTON           OK   EMERGENCY MNGR

            HOUSE EVACUATED DUE TO FLOODING. HIGHWAY 377
            CLOSED DOWN TO ONE LANE AND HIGHWAY 7 CLOSED
            IN PLACES AS WELL.

&&

MAD

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 19, 7:10 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Murray	50 min
May 19, 7:11 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Lincoln, Pontotoc, Pottawatomie, Seminole	64 min
May 19, 7:23 PM CDT	Tornado Warning Tornado observed	OUN	Carter, Murray	37 min
May 19, 7:38 PM CDT	Flash Flood Warning	OUN	Carter, Garvin, Murray	4 hr
May 19, 7:49 PM CDT	River Flood Warning	OUN	Pottawatomie, Seminole	22 hr
May 19, 7:51 PM CDT	Severe Thunderstorm Warning	OUN	Jefferson, Stephens	39 min
May 19, 7:54 PM CDT	Flash Flood Warning	OUN	Garvin, Pontotoc	3 hr
May 19, 7:54 PM CDT	Tornado Warning	OUN	Johnston, Murray	36 min
May 19, 8:03 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, Murray, Pontotoc	27 min
May 19, 8:08 PM CDT	Flash Flood Warning	OUN	Hughes, Pontotoc, Pottawatomie, Seminole	3 hr
May 19, 8:10 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Pontotoc, Seminole	80 min
May 19, 8:13 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Murray	32 min
May 19, 8:28 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Johnston, Murray, Pontotoc	47 min
May 19, 8:38 PM CDT	Flash Flood Warning	OUN	Carter, Cotton, Jefferson, Stephens	3 hr
May 19, 8:42 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Johnston, Pontotoc	48 min
May 19, 8:44 PM CDT	Flash Flood Warning	OUN	Atoka, Carter, Coal, Hughes, Johnston, Murray and 2 more	6 hr
May 19, 8:48 PM CDT	Tornado Warning	OUN	Johnston	27 min
May 19, 9:09 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Marshall, Murray, Pontotoc	51 min
May 19, 9:10 PM CDT	River Flood Warning	OUN	Cotton	35 hr
May 19, 9:10 PM CDT	River Flood Warning	OUN	Jefferson	29 hr
May 19, 9:20 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Pontotoc, Seminole	85 min
May 19, 9:24 PM CDT	Flash Flood Warning	OUN	Carter, Johnston, Marshall	3 hr
May 19, 9:25 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Coal, Johnston, Marshall, Pontotoc	80 min
May 19, 9:28 PM CDT	Tornado Warning	OUN	Johnston	32 min
May 19, 9:43 PM CDT	Flash Flood Warning	OUN	Garvin, Stephens	3 hr
May 19, 9:43 PM CDT	Flash Flood Warning	OUN	Cotton	3 hr
May 19, 9:44 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Marshall, Murray, Pontotoc	61 min
May 19, 9:57 PM CDT	Special Weather Statement	OUN	Jefferson	33 min
May 19, 9:58 PM CDT	Tornado Warning	OUN	Coal, Johnston, Pontotoc	32 min
May 19, 10:12 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Jefferson, Murray, Stephens	48 min
May 19, 10:17 PM CDT	Tornado Warning	OUN	Carter, Jefferson	28 min
May 19, 10:22 PM CDT	Tornado Warning	OUN	Coal	38 min
May 19, 10:34 PM CDT	Flash Flood Warning	OUN	Bryan, Johnston, Marshall	116 min
May 19, 10:34 PM CDT	River Flood Warning	OUN	Comanche, Cotton	11 hr
May 19, 10:39 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Coal, Hughes, Johnston, Marshall, Pontotoc	96 min
May 19, 10:39 PM CDT	Tornado Warning	OUN	Carter	14 min
May 19, 10:51 PM CDT	Flash Flood Warning Emergency	OUN	Carter, Johnston, Murray	3 hr
May 19, 10:55 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, Murray, Pontotoc	35 min
May 19, 10:56 PM CDT	River Flood Warning	OUN	Hughes, Seminole	58 hr
May 19, 10:58 PM CDT	Tornado Warning	OUN	Murray, Pontotoc	20 min
May 19, 11:04 PM CDT	Flash Flood Warning	OUN	Garvin, Pontotoc	3 hr
May 19, 11:13 PM CDT	Flash Flood Warning	OUN	Hughes, Pontotoc, Pottawatomie, Seminole	3 hr
May 19, 11:25 PM CDT	Tornado Warning	OUN	Atoka, Coal	35 min
May 19, 11:28 PM CDT	Flash Flood Warning	OUN	Carter, Garvin, Murray	3 hr
May 19, 11:29 PM CDT	Severe Thunderstorm Warning	OUN	Johnston, Murray, Pontotoc	34 min
May 19, 11:29 PM CDT	Tornado Warning	OUN	Coal, Johnston, Pontotoc	15 min
May 19, 11:42 PM CDT	Areal Flood Warning	OUN	Carter, Comanche, Cotton, Jefferson, Stephens	6 hr
May 19, 11:49 PM CDT	Severe Thunderstorm Warning	OUN	Bryan, Marshall	26 min
May 20, 12:08 AM CDT	Severe Thunderstorm Warning	OUN	Atoka, Bryan, Coal, Johnston, Marshall	82 min
May 20, 12:23 AM CDT	Tornado Warning	OUN	Bryan	37 min
May 20, 12:29 AM CDT	Areal Flood Warning	OUN	Garvin, Stephens	5 hr
May 20, 12:53 AM CDT	Tornado Warning	OUN	Atoka, Bryan	12 min
May 20, 1:20 AM CDT	Areal Flood Advisory	OUN	Atoka, Bryan, Coal, Johnston	3 hr
May 20, 1:28 AM CDT	Severe Thunderstorm Warning	OUN	Atoka, Bryan	51 min
May 20, 1:42 AM CDT	Areal Flood Warning	OUN	Carter, Garvin, Hughes, Murray, Pontotoc, Pottawatomie and 1 more	4 hr
May 20, 1:50 AM CDT	Flash Flood Warning	OUN	Atoka, Bryan, Coal, Johnston	3 hr
May 20, 2:11 AM CDT	River Flood Warning	OUN	Carter, Garvin, Murray	18 hr
May 20, 2:40 AM CDT	Areal Flood Warning	OUN	Atoka, Bryan, Coal, Hughes, Johnston, Marshall and 2 more	3 hr
May 20, 4:42 AM CDT	Areal Flood Warning	OUN	Atoka, Bryan, Coal, Johnston	3 hr
May 20, 5:40 AM CDT	Areal Flood Warning	OUN	Carter, Comanche, Cotton, Garvin, Jefferson, Murray and 1 more	9 hr
May 20, 5:43 AM CDT	Areal Flood Warning	OUN	Coal, Hughes, Johnston, Marshall, Pontotoc, Pottawatomie and 1 more	9 hr
May 20, 7:57 AM CDT	Areal Flood Warning	OUN	Atoka, Bryan	7 hr
May 20, 8:58 AM CDT	River Flood Warning	OUN	Carter, Johnston, Murray	35 hr
May 20, 10:00 AM CDT	River Flood Warning	OUN	Bryan	29 hr
May 20, 10:02 AM CDT	River Flood Warning	OUN	Atoka	5 days

Nearby

Flash Flood Warnings in Oklahoma, 2017 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.