Alert archive / Nebraska / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 127, NWS North Platte, NE
NWS North Platte, NE issued this severe thunderstorm warning at Jul 21, 1997, 4:39 AM MDT for Sheridan County, Nebraska. It was in force for 66 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Jul 21, 1997, 4:39 AM MDT (10:39 UTC)
- Expired
- Jul 21, 1997, 5:45 AM MDT
- In force
- 66 min
- Issued by
- NWS North Platte, NE
- Area
- Whole counties
County Sheridan County, NE
The radar
The North Platte radar (KLNX), 163 km from the middle of the area, began a volume at 10:42 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.
The nearest sounding before it
Rapid City, SD (KUNR), launched 00:00Z, 10.7 hours before the alert went out and 178 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
- 1157 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 750 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 116 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KLBF 211041 RRA SVRLBF NEC161-211145- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE NORTH PLATTE NE 539 AM CDT (439 AM MDT) MON JUL 21 1997 THE NATIONAL WEATHER SERVICE IN NORTH PLATTE NE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 545 AM MDT (645 AM CDT) FOR PEOPLE IN THE FOLLOWING LOCATION... IN THE NEBRASKA PANHANDLE ...NORTHERN SHERIDAN COUNTY AT 438 AM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY NORTH PLATTE DOPPLER RADAR 16 MILES EAST NORTHEAST OF CHADRON OR 9 MILES WEST SOUTHWEST OF WHITE CLAY MOVING EAST AT 20 MPH. DAMAGING HAIL AND/OR DESTRUCTIVE WINDS CAN BE EXPECTED NEAR... WHITE CLAY BY 500 AM MDT SEVER6E THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH... DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. M. MUTCHLER
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 North Platte, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 1:41 AM MDT, 2 hours 58 minutes earlier.
Area forecast discussion, Jul 21, 1:41 AM MDT, 2 hours 58 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTH PLATTE NE 240 AM CDT MON JUL 21 1997 ONCE AGAIN...THUNDERSTORMS ARE THE MAIN FORECAST CHALLENGE WITH THIS MORNING'S ISSUANCE... NGM AND AVN ARE SIMILAR TO 48 HOURS WITH MOST FEATURES. HOWEVER...THE AVN IS CONSISTENT WITH THE PREVIOUS THREE RUNS. SO...WHEREVER THE NGM AND AVN DON'T AGREE...PREFER THE AVN BECAUSE OF ITS CONSISTENCY WITH THE PREVIOUS MODEL RUNS. TEMPERATURE OUTPUT FROM THE NGM HAS BEEN ON TARGET THE PAST THREE DAYS...BUT THE AIRMASS HAS CHANGED SIGNIFICANTLY SINCE LATE LAST WEEK. THUS THE RECORD MAY NOT CONTINUE. IN FACT...THE AVN 1000-500MB THICKNESS FORECASTS ARE 60M LOWER THAN THOSE FROM THE NGM. SINCE THE OVERALL PATTERN HAS CHANGED (TEMPORARILY ANYWAY)... PREFER THE MORE CONSERVATIVE AVN TEMPERATURES FOR THIS FORECAST. RETURNING TO THE THUNDERSTORM CHALLENGE...THE AVN KEEPS A THETA-E RIDGE AT 700MB IN WESTERN NEBRASKA INTO TONIGHT AS WELL AS INSTABILITY (SFC LI'S ARE FORECAST TO BE -2 TO -4 IN WESTERN NEBRASKA THIS EVENING AND ZERO TO -2 INTO TONIGHT. AT 07Z...ADAP SURFACE MOISTURE CONVERGENCE CHART POINTS TO THE INCREASING LOW LEVEL MOISTURE IN THE NEBRASKA PANHANDLE AND IN THE EASTERN THIRD OF NEBRASKA. THESE ARE THE AREAS THAT THE AVN IS BUILDING LOBES OF THE 700MB THETA-E RIDGE. OF COURSE...WITHOUT SUFFICIENT LIFT...NONE OF THE ABOVE REALLY MATTERS. QUASI-G FORCING IS EXPECTED BY THE AVN TO BE WEAK ON THE HIGH PLAINS. HOWEVER...THE CIRCULATION AROUND THE SURFACE LOW PRESSURE IN NORTHEAST COLORADO WILL PROVIDE SOME FORCING UPSLOPE. ALSO THE WEAK SURFACE FRONT IN SOUTHWEST NEBRASKA AND NORTHWEST KANSAS WILL HELP FOCUS CONVECTION IN THAT AREA AS WELL. THE NEXT QUESTION IS TEMPERATURES. AVN THICKNESS PROGS PROVIDE NO CHANGE TODAY OR TUESDAY FROM YESTERDAY. SO TEMPERATURE VARIATIONS WILL DEPEND EXCLUSIVELY ON THE AMOUNT OF CLOUD COVER. A LACK OF LIFT IN THE NORTH CENTRAL ZONES SHOULD KEEP CLOUDS OUT OF THAT AREA. HOWEVER...IN THE SOUTHWEST ALONG THE SURFACE FRONT...CLOUDS WILL PROBABLY DOMINATE. SO TEMPERATURES TODAY IN THE SOUTHWEST ZONES WILL PROBABLY HAVE SOME DIFFICULTY REACHING THE UPPER 80S THAT WERE OBSERVED YESTERDAY. IN THE NORTH CENTRAL ZONES...HOWEVER...HIGHS NEAR 90 WOULD NOT BE A BIG SURPRISE. WITH A LITTLE LESS CLOUDINESS ON TUESDAY...UPPER 80S TO LOWER 90S SHOULD FIT OVER NEARLY ALL OF THE NORTH PLATTE AREA. RECOMMENDED FORECAST NEZ005-022>025-212115- CHERRY-GRANT-HOOKER-THOMAS- INCLUDING THE COMMUNITIES OF VALENTINE...MULLEN 400 AM CDT MON JUL 21 1997 .TODAY...MOSTLY SUNNY. HIGH 85 TO 90. NORTH WIND 5 TO 10 MPH. .TONIGHT...PARTLY CLOUDY WITH A 20 PERCENT CHANCE OF THUNDERSTORMS. LOW IN THE UPPER 50S. WIND BECOMING NEARLY CALM. .TUESDAY...MOSTLY SUNNY. HIGH AROUND 90. EAST WIND 5 TO 15 MPH. NEZ006>010-026-029-038-212115- KEYA PAHA-BOYD-BROWN-ROCK-HOLT-BLAINE-LOUP-GARFIELD-WHEELER-CUSTER- INCLUDING THE COMMUNITIES OF AINSWORTH...O NEILL...BURWELL...BROKEN BOW 400 AM CDT MON JUL 21 1997 .TODAY...MOSTLY SUNNY. HIGH 85 TO 90. NORTHEAST WIND 5 TO 10 MPH. .TONIGHT...MOSTLY CLEAR. LOW IN THE LOWER 60S. WIND BECOMING NEARLY CALM. TUESDAY...MOSTLY SUNNY. HIGH 85 TO 90. EAST WIND 5 TO 15 MPH. NEZ004-022-056-212115- SHERIDAN-GARDEN-DEUEL- INCLUDING THE COMMUNITIES OF GORDON...OSHKOSH...CHAPPEL 400 AM CDT MON JUL 21 1997 .TODAY...MOSTLY SUNNY. HIGH 85 TO 90. NORTH WIND 5 TO 10 MPH. .TONIGHT...PARTLY CLOUDY WITH A 30 PERCENT CHANCE OF THUNDERSTORMS. LOW IN THE MID 50S. WIND ECOMING NEARLY CALM. .TUESDAY...MOSTLY SUNNY. HIGH AROUND 90. NORTHEAST WIND 5 TO 15 MPH. NEZ035>037-056>059-069>071-212115- ARTHUR-MCPHERSON-LOGAN-DEUEL-KEITH-PERKINS-LINCOLN-CHASE-HAYES-FRONTIER- INCLUDING THE CITIES OF OGALLALA...NORTH PLATTE...IMPERIAL 400 AM CDT MON JUL 21 1997 .TODAY...PARTLY CLOUDY. HIGH IN THE MID 80S. NORTHEAST WIND 5 TO 10 MPH. .TONIGHT...PARTLY CLOUDY WITH A 30 PERCENT CHANCE OF THUNDERSTORMS. LOW 55 TO 60. WIND BECOMING NEARLY CALM. .TUESDAY...MOSTLY SUNNY. HIGH 85 TO 90. NORTHEAST WIND 5 TO 15 MPH. VTN UU 087/057 091/058 091 49020 ANW UU 087/062 088/060 090 49000 ONL UU 086/063 088/062 088 49000 BBW UU 085/061 088/059 090 49010 LBF BU 086/056 089/0|58 090 49030 OGA BU 085/057 089/060 091 49030 IML BU 086/058 090/061 092 49030 SPRINGER
Nearby
Severe Thunderstorm Warnings in Nebraska, 1997Every severe thunderstorm warning in 1997
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.