TORNADO WATCH #657

[NWIASpotter]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 657
NWS STORM PREDICTION CENTER NORMAN OK
240 PM CDT TUE JUL 20 2004


THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF


NORTHEAST NEBRASKA
SOUTHEAST SOUTH DAKOTA


EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 240 PM UNTIL 900
PM CDT.


TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.


THE TORNADO WATCH AREA IS ALONG AND 75 STATUTE MILES EAST AND WEST
OF A LINE FROM 25 MILES NORTHEAST OF HURON SOUTH DAKOTA TO 40
MILES WEST SOUTHWEST OF NORFOLK NEBRASKA.


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.


DISCUSSION...VERY UNSTABLE AIR MASS IN PLACE ACROSS WATCH AREA WITH
CAP BECOMING VERY WEAK WRN PORTION. RAPID DEVELOPMENT OF SEVERE
THUNDERSTORMS EXPECTED IN AREA OF BEST LOW LVL CONVERGENCE VICINITY
NEB/SD BORDER W OF YKN. VEERING SHEAR PROFILES SUPPORT SUPERCELLS
WHICH WILL ENHANCE POTENTIAL FOR VERY LARGE HAIL AND ISOLATED
TORNADOES.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600.
MEAN STORM MOTION VECTOR 27025.


...HALES

[Guest]

It misses the Omaha metro area by a couple of counties, but is close enough for me to keep an eye on.

[NWIASpotter]

The new SPC outlook that came out kept most of it the same. They stretched the tornado risk area a little further west, as well as the hatched area for hail. But here is the discussion for the area:


...NRN MS RIVER VALLEY INTO THE CENTRAL PLAINS...
LATEST MODEL GUIDANCE CONTINUES TO FAVOR INTENSE CONVECTIVE
DEVELOPMENT ALONG APPROACHING SURFACE FRONT OVER THE ERN
DAKOTAS/SWRN MN LATER THIS AFTERNOON. MID TO UPPER 70F SURFACE DEW
POINTS AND STRONG HEATING WILL CONTINUE TO DESTABILIZE AN ALREADY
UNSTABLE AIR MASS OVER THIS REGION. COMBINED EFFECTS OF FURTHER
HEATING AND LOW LEVEL CONVERGENCE SHOULD WEAKEN CAP AND ALLOW RAPID
THUNDERSTORMS DEVELOPMENT FROM S-CENTRAL SD/N-CENTRAL NEB INTO SWRN
MN BETWEEN 21-00Z. /REFERENCE SWOMCD 1740/. MID LEVEL LAPSE RATES
REMAIN QUITE STEEP WITH SUFFICIENT LOW AND DEEP LAYER SHEAR FOR
SUPERCELLS. THEREFORE EXPECT A THREAT OF VERY LARGE HAIL AND
ISOLATED TORNADOES...ESPECIALLY INTO ERN SD/NERN NEB/SWRN MN/NWRN IA
THROUGH THE MID EVENING. ACTIVITY MAY BUILD UPWARDS INTO AN MCS
LATER THIS EVENING AS BOUNDARY LAYER BECOMES CAPPED AND SWLY LLJ
INTENSIFIES.

[NWIASpotter]

Storms have begun to develop in North Central Nebraska. None of these storms have yet to become severe, but are being closely watched for the development of not only severe weather but also tornadoes. Latest Radar image puts a developing line of storms from O'niell southwestward into Loup county. Another line of storms west of those which are located in Rock county.

[ssom04]

The new SPC outlook that came out kept most of it the same. They stretched the tornado risk area a little further west, as well as the hatched area for hail. But here is the discussion for the area:


...NRN MS RIVER VALLEY INTO THE CENTRAL PLAINS...
LATEST MODEL GUIDANCE CONTINUES TO FAVOR INTENSE CONVECTIVE
DEVELOPMENT ALONG APPROACHING SURFACE FRONT OVER THE ERN
DAKOTAS/SWRN MN LATER THIS AFTERNOON. MID TO UPPER 70F SURFACE DEW
POINTS AND STRONG HEATING WILL CONTINUE TO DESTABILIZE AN ALREADY
UNSTABLE AIR MASS OVER THIS REGION. COMBINED EFFECTS OF FURTHER
HEATING AND LOW LEVEL CONVERGENCE SHOULD WEAKEN CAP AND ALLOW RAPID
THUNDERSTORMS DEVELOPMENT FROM S-CENTRAL SD/N-CENTRAL NEB INTO SWRN
MN BETWEEN 21-00Z. /REFERENCE SWOMCD 1740/. MID LEVEL LAPSE RATES
REMAIN QUITE STEEP WITH SUFFICIENT LOW AND DEEP LAYER SHEAR FOR
SUPERCELLS. THEREFORE EXPECT A THREAT OF VERY LARGE HAIL AND
ISOLATED TORNADOES...ESPECIALLY INTO ERN SD/NERN NEB/SWRN MN/NWRN IA
THROUGH THE MID EVENING. ACTIVITY MAY BUILD UPWARDS INTO AN MCS
LATER THIS EVENING AS BOUNDARY LAYER BECOMES CAPPED AND SWLY LLJ
INTENSIFIES.

Looks all three of us are under the gun!! 25% for wind hatched for hail 5% tornadoes looks I'm gonna catch myself a tornado today.........looks like I'm gonna go out in maybe 30 minutes and play the waiting game with my dad

[ssom04]

Oh damn this sucks, for the maybe 9th week in a row it seems like the storms will form in Nebraska and go east north east.......source:





Once storms develop in Eastern South Dakota ..I'll be happy because O'neill is like 8 hours away

[Aquawind]

Well they haven't exploded yet but they will..Dewpoints along the NE/SD Missouri river boarder are near 80 with temps in the 90s and full sun...that will change dramatically when the supercells get started..Yankton, SD to Sioux City, IA heads up!

http://www.rap.ucar.edu/weather/surface ... r&nplots=1

[NWIASpotter]

It has cleard off in Terril, up to 87 degrees, dew point is 73!! It is steamy outside, heat index is up there in the mid to upper 90s. Clouds are really forming nice over in Nebraska. If you make it into NW Iowa or extreme SW Minnesota and wanna change from listenin to NOAA radio, you can tune into 107.7 or 1240 AM. Thats the radio station that I'll prolly be at workin the radar, give you auto updates whenever theres a new warning and give you up to the second radar plots, haha. BUT still no warnings for NE!!

[NWIASpotter]

These storms should be ready to break anytime, check out the latest radar from North Platte.

http://weather.cod.edu/analysis/paulradar.pl?LNX

[ssom04]

It has cleard off in Terril, up to 87 degrees, dew point is 73!! It is steamy outside, heat index is up there in the mid to upper 90s. Clouds are really forming nice over in Nebraska. If you make it into NW Iowa or extreme SW Minnesota and wanna change from listenin to NOAA radio, you can tune into 107.7 or 1240 AM. Thats the radio station that I'll prolly be at workin the radar, give you auto updates whenever theres a new warning and give you up to the second radar plots, haha. BUT still no warnings for NE!!

Do you think I can get this in pipestone, MN......oh yeah. 85 and a cool 75 dew point lol

[NWIASpotter]

You might get AM but its not going to help you out weather wise. The area that they cover is Jackson, Nobles, and Rock. Then all of NW Iowa, but if you do get down here its good to listen too. On June 11 we were on the air for 3 hours straight.

[NWIASpotter]

There is still no warnings in NE!!! Radar has two storms having an 80 POSH(probabiliy of severe hail). One at 2 inches another at 2.5 inches. Several other storms are at 1/2 inch hail, but are my websites just not working or there is truly no warnings??

[Aquawind]

It' just getting started..

http://www.crh.noaa.gov/radar/loop/DS.p ... kfsd.shtml


SEVERE THUNDERSTORM WARNING
NEC071-115-202245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
443 PM CDT TUE JUL 20 2004

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
GARFIELD COUNTY IN NORTH CENTRAL NEBRASKA
LOUP COUNTY IN NORTH CENTRAL NEBRASKA

* UNTIL 545 PM CDT

* AT 440 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A SEVERE THUNDERSTORM. THIS STORM WAS LOCATED 13 MILES NORTH
NORTHWEST OF BURWELL...AND MOVING EAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL NORTH CENTRAL GARFIELD COUNTY AROUND 500 PM CDT
RURAL NORTHEASTERN GARFIELD COUNTY AROUND 530 PM CDT

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. IF A TORNADO
IS SPOTTED... ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A STURDY
STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

LAT...LON 4204 9962 4178 9961 4176 9881 4207 9878

$$

BUTTLER

[NWIASpotter]

Another new warning for Holt county, the storms are spreading up into South Dakota, it looks like they are going to take around an hour to get severe, the two earliest cells have become severe. I think that they should become more of some bow echos as they move towards the missouri valley. But for this moment I wouldn't be surprised to get a tornado warning or two out of these cells while they are still individual supercells.

[ssom04]

The storms are a craping out....very very un-organized

Now we wait for some new development farther NW into SW Minnesota And NW Iowa..........I also like the cell towards Spencer Nebraska