Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 267, NWS Tulsa, OK

May 18, 20174 counties in Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at May 18, 2017, 9:54 PM CDT for 4 counties in Oklahoma. It was in force for 36 min. 10 reports 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: May 18, 2017, 9:54 PM CDT (02:54 UTC)
Expired: May 18, 2017, 10:30 PM CDT
In force: 36 min
Issued by: NWS Tulsa, OK
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK

The radar

The Tulsa radar (KINX), 73 km from the middle of the area, began a volume at 02:55 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

Time	Report	Where	Remark
May 18, 9:55 PM CDT	TSTM WND DMG	3 Nne Vernon, OK	MCINTSOH COUNTY EM REPROTED A TRANSMISSION LINE DOWN ON HIGHWAY 9 BETWEEN THE INDIAN NATIONS TURNPIKE AND HIGHWAY 52. POWER OUTAGES THROUGHOUT MCINTOSH COUNTY WERE ALSO REPORTED.
May 18, 10:00 PM CDT	TORNADO	4 N Hanna, OK	A TORNADO DESTROYED A LARGE OUTBUILDING...DAMAGED A HOME...BLEW DOWN A METAL HIGH-VOLTAGE TRUSS TOWER...SNAPPED OR UPROOTED NUMEROUS TREES...AND SNAPPED WOODEN POWER POLES. BASED ON THIS DAMAGE...THE TORNADO WAS RATED EF-2.
May 18, 10:10 PM CDT	TSTM WND DMG	6 Nne Eufaula, OK	HIGH VOLTAGE TRANSMISSION LINES DOWN ON OLD HIGHWAY 69 SOUTH OF CHECOTAH, MAKING ROADWAY IMPASSABLE.
May 18, 10:10 PM CDT	TSTM WND DMG	Stidham, OK	MCINTOSH COUNTY EM REPORTING AT LEAST ONE HOME DESTROYED.
May 18, 10:12 PM CDT	TORNADO	1 S Stidham, OK	A TORNADO DESTROYED A MOBILE HOME...DAMAGED THE ROOFS OF SEVERAL OTHER HOMES...DESTROYED OUTBUILDINGS...SNAPPED OR UPROOTED NUMEROUS TREES...AND BLEW DOWN POWER POLES. BASED ON THIS DAMAGE...THE TORNADO WAS RATED EF-1.
May 18, 10:15 PM CDT	TSTM WND GST 66	4 Wnw Eufaula, OK
May 18, 10:15 PM CDT	TORNADO	2 Ene Stidham, OK	A TORNADO DESTROYED AN OUTBUILDING...DAMAGED A HOME...SNAPPED OR UPROOTED NUMEROUS TREES...AND BLEW DOWN POWER POLES. BASED ON THIS DAMAGE...THE TORNADO WAS RATED EF-1.
May 18, 10:20 PM CDT	TSTM WND DMG	Checotah, OK	POWER POLES DOWN.
May 18, 10:20 PM CDT	TSTM WND DMG	Checotah, OK	A STORAGE TANK AND BARN WERE DAMAGED IN THE CHECOTAH AREA, ALONG WITH DOWNED POWER LINES.
May 18, 10:30 PM CDT	TSTM WND GST 67	5 Sse Haskell, OK

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

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 7 storm reports to this severe thunderstorm warning; the first came 1 minutes after it went out.

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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 18, 6:02 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 2.9 hours before the alert went out and 234 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: 2055 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 1439 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 52 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

As transmitted.

211 
WUUS54 KTSA 190254
SVRTSA
OKC091-101-107-111-190330-
/O.NEW.KTSA.SV.W.0267.170519T0254Z-170519T0330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tulsa OK
954 PM CDT THU MAY 18 2017

The National Weather Service in Tulsa has issued a

* Severe Thunderstorm Warning for...
  McIntosh County in southeastern Oklahoma...
  Northwestern Muskogee County in east central Oklahoma...
  Central Okmulgee County in northeastern Oklahoma...
  Southeastern Okfuskee County in east central Oklahoma...

* Until 1030 PM CDT

* At 954 PM CDT, severe thunderstorms were located along a line
  extending from 3 miles south of Okmulgee State Park to 5 miles
  north of Dustin, moving northeast at 50 mph.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations in or near the path include...
  Okmulgee...                       Eufaula...
  Henryetta...                      Checotah...
  Morris...                         Dewar...
  Schulter...                       Taft...
  Boynton...                        Grayson...
  Council Hill...                   Hoffman...
  Stidham...                        Raiford...
  Vivian...                         Okmulgee State Park...
  Lake Eufaula State Park...        Wainwright...
  Hitchita...                       Bryant...

This includes Interstate 40 in Oklahoma between mile markers 231 and
265.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

A tornado watch remains in effect until midnight CDT for
southeastern, northeastern and east central Oklahoma.

LAT...LON 3579 9564 3576 9559 3579 9553 3530 9549
      3524 9598 3529 9598 3529 9607 3561 9618
TIME...MOT...LOC 0254Z 236DEG 45KT 3557 9609 3535 9601 

HAIL...1.00IN
WIND...60MPH
 
$$

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 Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at May 18, 9:19 PM CDT, 35 minutes earlier.

Area forecast discussion, May 18, 9:19 PM CDT, 35 minutes before

Area Forecast Discussion
National Weather Service Tulsa OK
919 PM CDT Thu May 18 2017

...UPDATE...

.DISCUSSION...
Strong to severe thunderstorms continue this evening with heavy
rainfall occurring in the stronger clusters. A marginal wind/hail
threat will likely persist into the overnight hours as storms
progress eastward into instability axis. In addition, given the
rainfall rates, the threat for localized flash flooding will also
be possible.

A quick look at the latest 00Z NAM indicates another round of
severe thunderstorms late Friday afternoon into Friday night.
Flash flooding could become a major concern, especially given the
rainfall that is ongoing. Update out shortly given latest radar
trends.

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Flash Flood Watch through Saturday morning for OKZ054>067-070-
     071.

AR...None.
&&

SHORT TERM...12

Hazardous weather outlook, May 18, 4:55 PM CDT, 4 hours 59 minutes before

Hazardous Weather Outlook
National Weather Service Tulsa OK
455 PM CDT Thu May 18 2017

ARZ001-002-010-011-019-020-029-OKZ049-053>076-191145-
Adair OK-Benton AR-Carroll AR-Cherokee OK-Choctaw OK-Craig OK-
Crawford AR-Creek OK-Delaware OK-Franklin AR-Haskell OK-Latimer OK-
Le Flore OK-Madison AR-Mayes OK-McIntosh OK-Muskogee OK-Nowata OK-
Okfuskee OK-Okmulgee OK-Osage OK-Ottawa OK-Pawnee OK-Pittsburg OK-
Pushmataha OK-Rogers OK-Sebastian AR-Sequoyah OK-Tulsa OK-Wagoner OK-
Washington OK-Washington AR-
455 PM CDT Thu May 18 2017

...SEVERE STORM POTENTIAL INCREASES THIS EVENING AND CONTINUES
INTO FRIDAY...

This Outlook is for Northwest and West Central Arkansas as well as
much of Eastern Oklahoma.

.DAY ONE...This evening through Tonight.

TORNADO.
	RISK...Limited.
 	AREA...West of highway 75.
    ONSET...after 6 PM.

SEVERE THUNDERSTORM.
	RISK...Elevated.
	AREA...Eastern Oklahoma and to a lesser extent Northwest Arkansas.
	ONSET...after 6 PM.

FLASH FLOOD.
	RISK...Limited.
	AREA...Northeast Oklahoma.
	ONSET...after midnight.

HEAVY RAIN.
	RISK...Elevated.
	AREA...Northeast Oklahoma.
	ONSET...after 6 PM.

SIGNIFICANT WINDS.
	RISK...Limited.
	AREA...Eastern Oklahoma and Western Arkansas.
	ONSET...ongoing.

DISCUSSION...

An enhanced to moderate risk of severe storms is forecast by early
evening into tonight across Eastern Oklahoma. Very large hail, in
excess of 2 inches in diameter, damaging winds and isolated
tornadoes are possible, with the greatest risk northwest of Tulsa. A
slight risk of severe storms is forecast for Western Arkansas late
tonight. Damaging winds and marginally severe hail would be the main
threats, mainly after midnight.

Strong to severe storms have develop this afternoon over western and
central Oklahoma.  These storms are expected to move east into the
region early this evening. The best chance for discrete surface
based cells, and thus the highest tornado and largest hail threat,
will be to the west of highway 75 this evening.

Storms are expected to gradually grow into clusters or lines this
evening as they move deeper into Eastern Oklahoma. Damaging winds
and large hail would be the main threats. An isolated tornado could
occur with any bowing line segments.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
Activation of the Regional Spotter Network Expected.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
FRIDAY and SATURDAY...Severe Thunderstorm Potential...High Wind
                        Potential...Heavy Rain Potential.
SUNDAY...No Hazards.
MONDAY...Severe Thunderstorm Potential.
TUESDAY...Thunderstorm Potential.
WEDNESDAY...No Hazards.

EXTENDED DISCUSSION...

Another round of strong to severe storms are expected Friday into
early Saturday as upper level system approaches the region.
Storms will fire along the dryline and cold front, becoming more
numerous with time. All modes of severe will be possible,
especially early when storms are more discrete, with storms again
merging into a line as they move east. Severe threat will
transition to more of a wind and heavy rain/flooding threat as
the night goes on. Convection will linger into Saturday while
gradually weakening, across northwest Arkansas and southeast
Oklahoma.

A system dropping through the region in northwest flow will bring
another round of storm potential Monday and Tuesday. A limited
risk for severe weather can be expected with this system.

weather.gov/tulsa Contains additional information.

In the hours before

Local storm report, May 18, 9:15 PM CDT, 39 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
915 PM CDT THU MAY 18 2017

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

0908 PM     TSTM WND GST     1 NW JENKS              36.03N 95.98W
05/18/2017  M60 MPH          TULSA              OK   ASOS

            MEASURED AT RIVERSIDE AIRPORT.

&&

KAH

Special weather statement, May 18, 9:35 PM CDT, 19 minutes before

Special Weather Statement
National Weather Service Tulsa OK
935 PM CDT THU MAY 18 2017

OKZ056-057-061-062-190300-
Craig OK-Rogers OK-Nowata OK-Mayes OK-
935 PM CDT THU MAY 18 2017

...SIGNIFICANT WEATHER ADVISORY FOR CRAIG...NORTHERN ROGERS...
NORTHERN MAYES AND EASTERN NOWATA COUNTIES UNTIL 1000 PM CDT...

At 935 PM CDT, a strong thunderstorm was located 5 miles northeast of
Chelsea, moving northeast at 45 mph.

Dime size hail and wind gusts up to 50 mph will be possible with this
storm.

Locations in or near the path include...
Vinita...                         Nowata...
Chelsea...                        Langley...
Adair...                          Welch...
Ketchum...                        Spavinaw...
Delaware...                       Foyil...
Bluejacket...                     Disney...
Lenapah...                        Talala...
Big Cabin...                      Pensacola...
New Alluwe...                     Hoot Owl...
Cherokee State Park...            Watova...

This includes Interstate 44 between mile markers 260 and 292.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A tornado watch remains in effect until midnight CDT for northeastern
Oklahoma.

LAT...LON 3699 9504 3697 9504 3695 9500 3634 9501
      3635 9539 3650 9574 3700 9558 3700 9501
TIME...MOT...LOC 0235Z 214DEG 37KT 3660 9539

69

Local storm report, May 18, 9:36 PM CDT, 18 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
936 PM CDT THU MAY 18 2017

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

0930 PM     TSTM WND GST     TULSA                   36.13N 95.92W
05/18/2017  E65 MPH          TULSA              OK   AMATEUR RADIO

            THUNDERSTORM WINDS ESTIMATED TO 65 MPH, TREE DAMAGED.

&&

JDS

Local storm report, May 18, 9:38 PM CDT, 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
938 PM CDT THU MAY 18 2017

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

0936 PM     TSTM WND GST     TULSA                   36.13N 95.92W
05/18/2017  E65 MPH          TULSA              OK   AMATEUR RADIO

            SHERIDAN AND 41ST

&&

JDS

Local storm report, May 18, 9:39 PM CDT, 15 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
939 PM CDT THU MAY 18 2017

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

0930 PM     TSTM WND GST     TULSA                   36.13N 95.92W
05/18/2017  E70 MPH          TULSA              OK   BROADCAST MEDIA

            TULSA HILLS

&&

JDS

Local storm report, May 18, 9:47 PM CDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
947 PM CDT THU MAY 18 2017

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

0939 PM     TSTM WND GST     4 NE TULSA              36.17N 95.87W
05/18/2017  M65 MPH          TULSA              OK   MESONET

&&

JDS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 18, 7:17 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee	43 min
May 18, 7:43 PM CDT	Special Weather Statement	TSA	Osage	32 min
May 18, 8:00 PM CDT	Special Weather Statement	TSA	Creek, Tulsa	45 min
May 18, 8:06 PM CDT	Special Weather Statement	TSA	Okfuskee	24 min
May 18, 8:10 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Rogers, Tulsa	35 min
May 18, 8:33 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee	42 min
May 18, 8:42 PM CDT	Severe Thunderstorm Warning	TSA	Osage, Rogers, Tulsa, Wagoner, Washington	48 min
May 18, 9:05 PM CDT	Areal Flood Advisory	TSA	Creek, Okfuskee, Okmulgee, Tulsa	115 min
May 18, 9:06 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Osage, Pawnee, Tulsa, Wagoner	24 min
May 18, 9:12 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee, Okmulgee	48 min
May 18, 9:26 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Osage, Rogers, Tulsa, Wagoner and 1 more	49 min
May 18, 9:35 PM CDT	Special Weather Statement	TSA	Craig, Nowata	25 min
May 18, 9:40 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Pittsburg	65 min
May 18, 9:48 PM CDT	Tornado Warning	TSA	Pittsburg	42 min
May 18, 10:00 PM CDT	Tornado Warning	TSA	McIntosh	30 min
May 18, 10:18 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Haskell, Latimer, McIntosh, Muskogee, Pittsburg and 1 more	57 min
May 18, 10:22 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Mayes, Muskogee, Okmulgee, Rogers, Tulsa and 1 more	38 min
May 18, 10:23 PM CDT	Tornado Warning	TSA	Muskogee, Wagoner	37 min
May 18, 10:28 PM CDT	Tornado Warning	TSA	Cherokee, McIntosh, Muskogee, Sequoyah	47 min
May 18, 10:37 PM CDT	Tornado Warning	TSA	Cherokee, Mayes, Muskogee, Wagoner	38 min
May 18, 10:42 PM CDT	Areal Flood Advisory	TSA	Rogers	3 hr
May 18, 10:57 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee, Delaware, Haskell, LeFlore, Mayes and 3 more	48 min
May 18, 11:00 PM CDT	Tornado Warning	TSA	Adair, Cherokee	45 min
May 18, 11:01 PM CDT	Tornado Warning	TSA	Cherokee, Delaware, Mayes, Wagoner	44 min
May 18, 11:12 PM CDT	Severe Thunderstorm Warning	TSA	Craig, Delaware, Mayes, Ottawa, Rogers	48 min
May 18, 11:12 PM CDT	Severe Thunderstorm Warning	TSA	Haskell, Latimer, LeFlore, Pittsburg, Pushmataha	48 min
May 18, 11:31 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Delaware, Sequoyah	59 min
May 18, 11:32 PM CDT	Tornado Warning	TSA	Delaware	43 min
May 18, 11:34 PM CDT	Tornado Warning	TSA	Adair, Delaware	41 min
May 18, 11:42 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Pittsburg	48 min
May 18, 11:48 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore, Sequoyah	42 min
May 18, 11:58 PM CDT	Severe Thunderstorm Warning	TSA	Latimer, LeFlore, Pittsburg, Pushmataha	62 min
May 19, 2:16 AM CDT	Special Weather Statement	TSA	Pawnee	44 min
May 19, 3:26 AM CDT	Special Weather Statement	TSA	Tulsa	34 min
May 19, 3:58 AM CDT	Special Weather Statement	TSA	Tulsa	32 min
May 19, 8:46 AM CDT	River Flood Warning	TSA	Osage	23 hr
May 19, 8:46 AM CDT	River Flood Warning	TSA	Osage, Tulsa	62 hr
May 19, 8:46 AM CDT	River Flood Warning	TSA	Tulsa	71 hr
May 19, 8:46 AM CDT	River Flood Warning	TSA	Creek	38 hr
May 19, 8:56 AM CDT	River Flood Warning	TSA	Washington	71 hr
May 19, 8:56 AM CDT	River Flood Warning	TSA	Rogers, Tulsa	4 days
May 19, 8:56 AM CDT	River Flood Warning	TSA	Ottawa	5 days
May 19, 10:57 AM CDT	Special Weather Statement	TSA	Tulsa	33 min
May 19, 11:07 AM CDT	Special Weather Statement	TSA	Osage	23 min
May 19, 1:18 PM CDT	Special Weather Statement	TSA	Muskogee	27 min
May 19, 1:47 PM CDT	Special Weather Statement	TSA	Cherokee, Delaware, Mayes	43 min
May 19, 2:10 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee, Delaware, Mayes	26 min
May 19, 2:21 PM CDT	River Flood Advisory	TSA	Cherokee	3 days
May 19, 2:34 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Delaware	41 min
May 19, 3:46 PM CDT	Special Weather Statement	TSA	Adair	29 min
May 19, 4:03 PM CDT	Special Weather Statement	TSA	Okfuskee, Okmulgee	27 min
May 19, 4:18 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee, Okmulgee, Tulsa, Wagoner	42 min
May 19, 4:42 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee, Okmulgee	48 min
May 19, 5:01 PM CDT	Special Weather Statement	TSA	Wagoner	29 min
May 19, 5:15 PM CDT	Special Weather Statement	TSA	Mayes, Okmulgee, Wagoner	30 min
May 19, 5:16 PM CDT	Areal Flood Advisory	TSA	Creek, Mayes, Muskogee, Okfuskee, Okmulgee, Rogers and 2 more	119 min
May 19, 5:20 PM CDT	Severe Thunderstorm Warning	TSA	Delaware, Mayes	2 min
May 19, 5:24 PM CDT	Severe Thunderstorm Warning	TSA	Delaware, Mayes	51 min
May 19, 6:04 PM CDT	Flash Flood Warning	TSA	Creek, Okfuskee, Okmulgee	8 hr
May 19, 6:15 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Delaware, Mayes, Muskogee, Ottawa, Wagoner	60 min
May 19, 6:19 PM CDT	Special Weather Statement	TSA	Okfuskee	26 min
May 19, 6:28 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee, Okmulgee	62 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2017 Every severe thunderstorm 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.