Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 130, NWS Norman, OK

April 27, 2021Cotton County, Tillman County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 27, 2021, 8:10 PM CDT for Cotton County, Tillman County, Oklahoma. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Apr 27, 2021, 8:10 PM CDT (01:10 UTC)
Expired: Apr 27, 2021, 9:00 PM CDT
In force: 50 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Cotton County, OK, Tillman County, OK

The radar

The Altus AFB radar (KFDR), 37 km from the middle of the area, began a volume at 01:09 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 severe thunderstorm 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 watch it was issued in

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

Issued	Product	Office	Lasted
Apr 27, 1:57 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 1.2 hours before the alert went out and 160 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: 661 J/kg
Mixed-layer CIN: -196 J/kg
Mixed-layer LCL: 1104 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 228 m²/s²
0-3 km storm-relative helicity: 198 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.0

Open this sounding in Storm Lab

The text

As transmitted.

925 
WUUS54 KOUN 280110
SVROUN
OKC033-141-280200-
/O.NEW.KOUN.SV.W.0130.210428T0110Z-210428T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
810 PM CDT Tue Apr 27 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Western Cotton County in southwestern Oklahoma...
  Southeastern Tillman County in southwestern Oklahoma...

* Until 900 PM CDT.

* At 810 PM CDT, a severe thunderstorm was located 6 miles southwest
  of Grandfield, moving northeast at 20 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* Locations impacted include...
  Grandfield, Randlett, Devol, Cookietown and Taylor. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3412 9856 3413 9855 3415 9858 3417 9864
      3413 9869 3413 9874 3414 9880 3416 9881
      3415 9887 3421 9887 3442 9853 3442 9851
      3444 9850 3417 9832 3412 9855
TIME...MOT...LOC 0110Z 241DEG 19KT 3417 9877 

HAIL...1.50IN
WIND...60MPH
 
$$

..speg.

1 follow-up statement

073 
WWUS54 KOUN 280158
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
858 PM CDT Tue Apr 27 2021

OKC033-141-280208-
/O.EXP.KOUN.SV.W.0130.000000T0000Z-210428T0200Z/
Cotton OK-Tillman OK-
858 PM CDT Tue Apr 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN COTTON AND
SOUTHEASTERN TILLMAN COUNTIES WILL EXPIRE AT 900 PM CDT...
                 
The storm which prompted the warning has weakened below severe
limits, therefore the warning will be allowed to expire.  However
small hail and heavy rain are still possible with this thunderstorm.

LAT...LON 3412 9856 3413 9855 3415 9858 3417 9864
      3413 9869 3413 9874 3414 9880 3416 9881
      3415 9887 3421 9887 3442 9853 3442 9851
      3444 9850 3417 9832 3412 9855
TIME...MOT...LOC 0158Z 241DEG 19KT 3429 9851 

$$

03

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 Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 27, 6:36 PM CDT, 1 hour 34 minutes earlier.

Area forecast discussion, Apr 27, 6:36 PM CDT, 1 hour 34 minutes before

Area Forecast Discussion
National Weather Service Norman OK
636 PM CDT Tue Apr 27 2021

...New AVIATION, UPPER AIR...

.SHORT TERM...
(This evening through Wednesday)
Issued at 202 PM CDT Tue Apr 27 2021

Thunderstorm initiation has begun in west Texas and this activity
will spread and expand northeast this afternoon and this evening.
Clearing of the mid and high level clouds will allow
destabilization across the west this afternoon, so instability
will increase this afternoon in these area. It is still a little
more in question about how much destabilization we will get
farther northeast as to whether storms toward central Oklahoma
will be surface-based or more elevated. But with time overnight,
the threat will shift more from severe thunderstorm potential to
heavy rain potential as thunderstorm coverage increases. We issued
a Flood Watch already for this scenario as forecast precipitable
water amounts of 1.75" to 2" are quite extreme for late April.

&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 244 PM CDT Tue Apr 27 2021

The storm system over the southern Plains will be slow to move
away, so rain/thunderstorm chances will diminish only slowly
Wednesday night into Thursday. Rain will end gradually from
northwest to southeast, while drier air moves into the region from
the northwest.

The upper-level system responsible for the current rain/storms is
forecast to cut off over Texas. The various models have very
different ideas as to how the cutoff low will evolve, as is
commonly the case. This leads to rather low-confidence forecasts
from the weekend into early next week.

The most likely scenario is that the upper low will drift slowly
east, similar to, but a little faster than, the 12Z ECMWF outlook.
This would cause a bit of moisture return over our southeast this
weekend, leading to low chances for showers on Sunday. Beyond
that, there is no clear preference in outcomes, so the forecast is
basically a mix of the possibilities.

&&

.AVIATION...
(00Z TAFS)
Issued at 629 PM CDT Tue Apr 27 2021

Widespread TSRA are expected through the period. There will be
early breaks in the activity over southeast and northwest
Oklahoma, but rain and storms should fill in over most of the
region overnight and especially early Wednesday. Ceilings are
expected to be lowest within a few hours either side of sunrise
Wednesday, with slight improvement through the day.

CmS
&&

.UPPER AIR...
Issued at 629 PM CDT Tue Apr 27 2021

No upper air flights are currently planned for tonight.

&&

.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK  78  64  75  56 /  40  70  80  60
Hobart OK         82  62  78  53 /  30  70  70  40
Wichita Falls TX  83  67  79  57 /  30  70  80  50
Gage OK           82  56  75  48 /  20  30  40  40
Ponca City OK     81  64  77  55 /  20  70  80  60
Durant OK         76  67  79  61 /  40  50  80  90

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Thursday morning for OKZ008-013-019-020-
     023>032-038>048-050>052.

TX...Flood Watch through Thursday morning for TXZ086-089-090.

&&

SHORT TERM...26
LONG TERM....23
AVIATION...23

Hazardous weather outlook, Apr 27, 12:41 PM CDT, 7 hours 29 minutes before

Hazardous Weather Outlook
National Weather Service Norman OK
1241 PM CDT Tue Apr 27 2021

OKZ004>048-050>052-TXZ083>090-281130-
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-
1241 PM CDT Tue Apr 27 2021

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

.DAY ONE...This Afternoon and Tonight...

.Thunderstorms...
Severe thunderstorms are possible this afternoon into tonight. A
Slight Risk covers most of Oklahoma and all of western north
Texas. While large hail will be the primary hazard over the
larger area, all severe weather hazards are possible, especially
across western north Texas and southwest Oklahoma. The greatest
risk for severe weather will be late afternoon into the early
evening.

.Heavy Rainfall and Flooding...
Heavy rainfall with the potential for flooding is possible
tonight.

.Fire Weather...
Elevated fire weather conditions are possible across northwest
Oklahoma late morning into this afternoon.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday...

.Thunderstorms...
There is a Slight Risk of thunderstorms south of line from near
Woodward, to Enid, and to Stillwater. Thunderstorms are forecast
to exit to the east Wednesday morning with additional
thunderstorms expected to redevelop by the afternoon. While large
hail will be the primary hazard over the larger area, all severe
weather hazards are possible, especially across western north
Texas and southwest Oklahoma. Thunderstorms should exit the area
early Thursday morning.

.Heavy Rainfall and Flooding...
Heavy rainfall and flooding will continue to be a hazard on
Wednesday into early Thursday. During this period, the greatest
risk for flooding will be across southeast and south central
Oklahoma.

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, Apr 27, 4:39 PM CDT, 3 hours 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
439 PM CDT TUE APR 27 2021

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

0437 PM     HAIL             3 WNW GRAYBACK          34.01N 99.22W
04/27/2021  E1.00 INCH       WILBARGER          TX   TRAINED SPOTTER

&&

RCB

Special weather statement, Apr 27, 5:50 PM CDT, 2 hours 20 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
550 PM CDT Tue Apr 27 2021

OKZ037-TXZ083>085-272315-
Tillman OK-Foard TX-Wilbarger TX-Hardeman TX-
550 PM CDT Tue Apr 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR western Tillman...east central
Foard...northwestern Wilbarger and southeastern Hardeman Counties
Until 615 PM CDT...

AT 549 PM CDT, a strong thunderstorm was located near Lockett, moving
northeast at 60 MPH.

HAZARDS INCLUDE...
Hail up to the size of nickels...
Wind gusts to 50 MPH...

LAT...LON 3438 9927 3437 9924 3434 9923 3434 9919
      3437 9920 3437 9922 3439 9921 3439 9923
      3441 9924 3458 9905 3440 9881 3401 9938
      3394 9957 3406 9963
TIME...MOT...LOC 2249Z 223DEG 51KT 3413 9935

JT

Special weather statement, Apr 27, 6:24 PM CDT, 1 hour 46 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
624 PM CDT Tue Apr 27 2021

OKZ036-037-TXZ083>085-087-088-280000-
Tillman OK-Jackson OK-Foard TX-Knox TX-Wilbarger TX-Baylor TX-
Hardeman TX-
624 PM CDT Tue Apr 27 2021

...SIGNIFICANT WEATHER ADVISORY FOR western Tillman...southeastern
Jackson...southeastern Foard...northeastern Knox...Wilbarger...
northwestern Baylor and southeastern Hardeman Counties Until 700 PM
CDT...

AT 622 PM CDT, strong thunderstorms were along a line extending from
3 miles northwest of Odell to 7 miles southeast of Medicine Mound to
10 miles south of Thalia, moving northeast at 55 MPH.

HAZARDS INCLUDE...
Hail up to the size of nickels...
Wind gusts to 50 MPH...

LAT...LON 3358 9967 3441 9959 3464 9910 3464 9908
      3393 9903
TIME...MOT...LOC 2322Z 232DEG 47KT 3437 9947 3413 9949 3383 9950

JT

Local storm report, Apr 27, 7:21 PM CDT, 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
721 PM CDT TUE APR 27 2021

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

0717 PM     FUNNEL CLOUD     6 SW LOVELAND           34.24N 98.85W
04/27/2021                   TILLMAN            OK   TRAINED SPOTTER

&&

RCB

Local storm report, Apr 27, 7:43 PM CDT, 27 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
743 PM CDT TUE APR 27 2021

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

0735 PM     TSTM WND GST     3 W GRANDFIELD          34.23N 98.74W
04/27/2021  M63 MPH          TILLMAN            OK   MESONET

&&

RCB

Local storm report, Apr 27, 8:10 PM CDT, 0 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
810 PM CDT TUE APR 27 2021

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

0807 PM     HAIL             ELECTRA                 34.03N 98.91W
04/27/2021  E1.25 INCH       WICHITA            TX   TRAINED SPOTTER

            REPORT FROM MPING: HALF DOLLAR (1.25 IN.).

&&

RCB

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 27, 7:15 PM CDT	Severe Thunderstorm Warning	OUN	Tillman	45 min
Apr 27, 7:19 PM CDT	Tornado Warning	OUN	Tillman	41 min
Apr 27, 7:53 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Tillman	52 min
Apr 27, 8:46 PM CDT	Special Weather Statement	OUN	Comanche	29 min
Apr 27, 9:01 PM CDT	Special Weather Statement	OUN	Cotton	29 min
Apr 27, 9:55 PM CDT	Special Weather Statement	OUN	Stephens	50 min
Apr 27, 10:35 PM CDT	Special Weather Statement	OUN	Pottawatomie	25 min
Apr 27, 10:43 PM CDT	Special Weather Statement	OUN	Tillman	32 min
Apr 27, 10:46 PM CDT	Special Weather Statement	OUN	McClain	44 min
Apr 27, 11:05 PM CDT	Special Weather Statement	OUN	Pottawatomie, Seminole	25 min
Apr 27, 11:24 PM CDT	Special Weather Statement	OUN	Cleveland, Garvin, McClain	36 min
Apr 27, 11:41 PM CDT	Special Weather Statement	OUN	Seminole	34 min
Apr 27, 11:42 PM CDT	Special Weather Statement	OUN	Cotton	33 min
Apr 27, 11:49 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Murray	26 min
Apr 27, 11:58 PM CDT	Tornado Warning	OUN	Garvin, McClain	17 min
Apr 28, 12:13 AM CDT	Tornado Warning Tornado observed	OUN	Cleveland, Garvin, McClain, Pottawatomie	32 min
Apr 28, 12:27 AM CDT	Areal Flood Advisory	OUN	Carter, Garvin, McClain, Murray, Stephens	3 hr
Apr 28, 12:47 AM CDT	Flash Flood Warning	OUN	Garvin	8 hr
Apr 28, 12:59 AM CDT	Areal Flood Advisory	OUN	Cleveland, Pottawatomie, Seminole	4 hr
Apr 28, 1:31 AM CDT	Special Weather Statement	OUN	Pottawatomie	29 min
Apr 28, 1:40 AM CDT	Areal Flood Advisory	OUN	Pontotoc, Pottawatomie, Seminole	3 hr
Apr 28, 1:43 AM CDT	Special Weather Statement	OUN	Seminole	32 min
Apr 28, 3:11 AM CDT	Flash Flood Warning	OUN	Carter, Cotton, Jefferson, Murray, Stephens	6 hr
Apr 28, 3:28 AM CDT	Special Weather Statement	OUN	Garvin	32 min
Apr 28, 3:56 AM CDT	Special Weather Statement	OUN	Murray	34 min
Apr 28, 4:09 AM CDT	Special Weather Statement	OUN	Garvin	36 min
Apr 28, 4:25 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, McClain, Stephens	35 min
Apr 28, 4:27 AM CDT	Special Weather Statement	OUN	Pontotoc	33 min
Apr 28, 5:05 AM CDT	Special Weather Statement	OUN	Hughes	25 min
Apr 28, 5:09 AM CDT	Areal Flood Advisory	OUN	Hughes, Pontotoc, Pottawatomie, Seminole	4 hr
Apr 28, 5:24 AM CDT	River Flood Warning	OUN	Pottawatomie, Seminole	18 hr
Apr 28, 6:19 AM CDT	River Flood Advisory	OUN	Carter, Garvin, Murray	4 hr
Apr 28, 6:33 AM CDT	Flash Flood Warning	OUN	Garvin, Hughes, McClain, Murray, Pontotoc, Pottawatomie and 1 more	4 hr
Apr 28, 8:02 AM CDT	Special Weather Statement	OUN	Murray	28 min
Apr 28, 8:15 AM CDT	Special Weather Statement	OUN	Pontotoc	30 min
Apr 28, 8:33 AM CDT	Severe Thunderstorm Warning	OUN	Hughes, Pontotoc	27 min
Apr 28, 8:47 AM CDT	Special Weather Statement	OUN	Pontotoc	28 min
Apr 28, 8:48 AM CDT	Areal Flood Advisory	OUN	Coal, Hughes, Johnston, Pontotoc	3 hr
Apr 28, 8:56 AM CDT	Special Weather Statement	OUN	Hughes	34 min
Apr 28, 9:03 AM CDT	Flash Flood Warning	OUN	Carter, Garvin, Jefferson, McClain, Murray, Stephens	117 min
Apr 28, 9:14 AM CDT	Flash Flood Warning Considerable damage threat	OUN	Coal, Hughes, Pontotoc, Seminole	3 hr
Apr 28, 9:16 AM CDT	Flash Flood Warning Considerable damage threat	OUN	Coal, Hughes, Pontotoc, Seminole	3 hr
Apr 28, 9:53 AM CDT	River Flood Warning	OUN	Hughes, Seminole	35 hr
Apr 28, 9:56 AM CDT	River Flood Warning	OUN	Carter, Garvin, Murray	13 hr
Apr 28, 9:59 AM CDT	Areal Flood Advisory	OUN	Carter, Jefferson, Johnston, Love, Marshall, Murray	3 hr
Apr 28, 10:46 AM CDT	Flash Flood Warning	OUN	Carter, Johnston, Love, Marshall	4 hr
Apr 28, 11:01 AM CDT	Areal Flood Warning	OUN	Carter, Garvin, Hughes, McClain, Murray, Pontotoc and 2 more	3 hr
Apr 28, 11:39 AM CDT	River Flood Advisory	OUN	Hughes	2 hr
Apr 28, 11:43 AM CDT	Special Weather Statement	OUN	Kay	47 min
Apr 28, 11:59 AM CDT	Special Weather Statement	OUN	Garfield, Kingfisher	31 min
Apr 28, 12:16 PM CDT	Areal Flood Warning	OUN	Coal, Hughes, Pontotoc, Seminole	4 hr
Apr 28, 1:20 PM CDT	Areal Flood Advisory	OUN	Bryan, Marshall	3 hr
Apr 28, 1:31 PM CDT	Areal Flood Advisory	OUN	Cleveland, Grady, McClain, Oklahoma	4 hr
Apr 28, 1:31 PM CDT	Special Weather Statement	OUN	Garfield	29 min
Apr 28, 1:45 PM CDT	Special Weather Statement	OUN	Garfield	30 min
Apr 28, 2:07 PM CDT	River Flood Warning	OUN	Hughes	9 hr
Apr 28, 2:22 PM CDT	Special Weather Statement	OUN	Love	23 min
Apr 28, 2:38 PM CDT	Special Weather Statement	OUN	Canadian	22 min
Apr 28, 2:46 PM CDT	Areal Flood Advisory	OUN	Carter, Johnston, Love, Marshall	3 hr
Apr 28, 3:17 PM CDT	Areal Flood Advisory	OUN	Caddo, Canadian, Grady, Kingfisher, Logan, Oklahoma	3 hr
Apr 28, 3:22 PM CDT	Special Weather Statement	OUN	Logan	23 min
Apr 28, 3:52 PM CDT	Special Weather Statement	OUN	Caddo	23 min
Apr 28, 3:54 PM CDT	River Flood Warning	OUN	Carter, Johnston, Murray	31 hr
Apr 28, 3:56 PM CDT	Areal Flood Advisory	OUN	Caddo, Comanche	3 hr
Apr 28, 4:19 PM CDT	Special Weather Statement	OUN	Lincoln	26 min
Apr 28, 4:21 PM CDT	Special Weather Statement	OUN	Caddo	24 min
Apr 28, 4:23 PM CDT	Special Weather Statement	OUN	Logan, Noble	37 min
Apr 28, 4:48 PM CDT	Special Weather Statement	OUN	Grady	42 min
Apr 28, 4:56 PM CDT	Areal Flood Advisory	OUN	Noble	3 hr
Apr 28, 5:01 PM CDT	Special Weather Statement	OUN	Noble	44 min
Apr 28, 5:23 PM CDT	Special Weather Statement	OUN	Johnston	37 min
Apr 28, 5:36 PM CDT	Severe Thunderstorm Warning	OUN	Atoka, Johnston	24 min
Apr 28, 5:40 PM CDT	Special Weather Statement	OUN	Oklahoma	35 min
Apr 28, 6:02 PM CDT	Special Weather Statement	OUN	Atoka	28 min
Apr 28, 6:26 PM CDT	Special Weather Statement	OUN	Washita	49 min
Apr 28, 6:59 PM CDT	Special Weather Statement	OUN	Caddo	46 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2021 Every severe thunderstorm warning in 2021

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.