Alert archive / North Dakota / Tornado Watches in 2007
Tornado Watch 245
The Storm Prediction Center issued this tornado watch at May 6, 2007, 1:07 PM CDT for 28 counties in North Dakota. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- May 6, 2007, 1:07 PM CDT (18:07 UTC)
- Expired
- May 6, 2007, 7:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 60 kt
All 28 counties
Barnes County, ND, Benson County, ND, Burleigh County, ND, Cavalier County, ND, Eddy County, ND, Emmons County, ND, Foster County, ND, Grant County, ND, Griggs County, ND, Kidder County, ND, LaMoure County, ND, Logan County, ND, McHenry County, ND, McIntosh County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Nelson County, ND, Oliver County, ND, Pierce County, ND, Ramsey County, ND, Rolette County, ND, Sheridan County, ND, Sioux County, ND, Stutsman County, ND, Towner County, ND, Ward County, ND, Wells County, ND
The radar
The Bismarck radar (KBIS), 43 km from the middle of the area, began a volume at 18:08 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 6, 1:15 PM CDT | Tornado Warning | BIS | Grant | 30 min |
| May 6, 1:46 PM CDT | Tornado Warning | BIS | Grant, Morton | 29 min |
| May 6, 4:38 PM CDT | Severe Thunderstorm Warning | BIS | Pierce | 21 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Bismarck Municip, ND (KBIS), launched 12:00Z, 6.1 hours before the alert went out and 41 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.
- Mixed-layer CAPE
- 659 J/kg
- Mixed-layer CIN
- -84 J/kg
- Mixed-layer LCL
- 562 m above ground
- 0-6 km bulk shear
- 67 kt
- 0-1 km storm-relative helicity
- 288 m²/s²
- 0-3 km storm-relative helicity
- 292 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 6.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 061807
SEL5
SPC WW 061807
NDZ000-070000-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 245
NWS STORM PREDICTION CENTER NORMAN OK
110 PM CDT SUN MAY 6 2007
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
LARGE PART OF NORTH DAKOTA
EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 110 PM UNTIL 700
PM CDT.
TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 60 MILES SOUTH OF BISMARCK
NORTH DAKOTA TO 60 MILES NORTH NORTHWEST OF DEVILS LAKE NORTH
DAKOTA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 243...WW 244...
DISCUSSION...THUNDERSTORMS INCREASING JUST AHEAD OF THE
SURFACE/UPPER LOW THAT IS TRACKING NEWD ACROSS CENTRAL ND. STRONG
DEEP LAYER SHEAR AHEAD OF LOW COUPLED WITH MLCAPES TO 1000 J/KG
SUPPORT BOTH SUPERCELLS AND SHORT LINE SEGMENTS. TORNADOES WILL BE
MOST LIKELY WITH ANY SUPERCELL THAT FORMS AS THE ACTIVITY DEVELOPS
NEWD THRU THE AFTERNOON.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 22035.
...HALESSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 5, 7:58 PM CDT | Mesoscale Discussion | SPC | Barnes, Burleigh, Cass, Dickey, Emmons, Foster and 10 more | 2 hr |
| May 6, 12:07 PM CDT | Mesoscale Discussion | SPC | Adams, Burleigh, Dunn, Grant, Hettinger, McHenry and 8 more | 113 min |
| May 6, 6:04 PM CDT | Mesoscale Discussion | SPC | Benson, Burleigh, Eddy, Foster, Kidder, Logan and 10 more | 56 min |
Nearby
Tornado Watches in North Dakota, 2007Every tornado watch in 2007
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.