SEVERECAST DAY 34 – MIDNIGHT, SATURDAY, APRIL 3

…NO SEVERE THUNDERSTORMS EXPECTED IN OKLAHOMA SATURDAY…

A STRONG UPPER STORM SYSTEM LOCATED JUST EAST OF THE STATE WILL MOVE NORTHEASTWARD DURING THE PERIOD.  A GENERAL WEST OR SOUTHWEST UPPER LEVEL FLOW WILL PREVAIL TODAY… AND ANOTHER LARGE STORM SYSTEM WILL BE APPROACHING THE WEST COAST.

THE SURFACE COLD FRONT ASSOCIATED WITH THE PREVIOUS SYSTEM HAS NOT MADE MUCH SOUTHWARD PROGRESS AND IT DOESN’T APPEAR AS IF IT WILL ENTER MUCH OF THE GULF.  THIS FRONT WILL START TO BECOME DIFFUSE LATE THIS AFTERNOON AND SOUTH WINDS WILL RETURN TO OKLAHOMA.

THE ATMOSPHERE TODAY WILL BE DRY AND THERE WILL BE LITTLE IN THE WAY OF LIFTING ACROSS THE SOUTHERN PLAINS… NO THUNDERSTORMS ARE EXPECTED.

MOISTURE RETURN ON SUNDAY MAY LEAD TO THUNDERSTORM DEVELOPMENT LATE IN THE DAY – MAINLY OVER NORTHERN OKLAHOMA.  THE THREAT OF SEVERE WEATHER WILL NEED TO BE ADDRESSED.

THE ATMOSPHERE WILL BECOME INCREASINGLY MOIST AND UNSTABLE ON MONDAY.  A FAIRLY STRONG CAP MAY SERVE TO KEEP THE DRY LINE NEAR THE WESTERN BORDER QUIET.  HOWEVER… THE THREAT OF SEVERE WEATHER WILL NEED TO BE ADDRESSED ON THIS DAY AS WELL AS ANY STORMS THAT FORM WILL LIKELY BE SEVERE.

ON THIS DATE IN 1964… THE MAIN NEWS IN THE REGION WAS A LARGE TORNADO THAT MOVED THROUGH WICHITA FALLS, TEXAS.  LATER… TORNADOES WOULD CROSS THE RED RIVER HITTING AREAS NEAR LAKE TEXOMA LODGE… NEAR SUMMERFIELD IN LEFLORE COUNTY… AND NEAR MADILL.

SEVERECAST DAY 33 – MIDNIGHT, FRIDAY, APRIL 2

…SEVERE THUNDERSTORMS LIKELY IN EASTERN OKLAHOMA TODAY…

A DEEP TROUGH OF LOW PRESSURE IS SHIFTING EASTWARD INTO THE PLAINS… THERE ARE SEVERAL VORT CENTERS THAT ARE ROTATING THROUGH THE BASE OF THE TROUGH.  ONE SUCH CENTER – FORECAST TO BE VERY STRONG – WILL MOVE ACROSS NORTH TEXAS AND INTO ARKANSAS BY SATURDAY MORNING.

IN ADVANCE OF THE STORM… A SLOW BUT STEADY INCREASE IN LOW LEVEL MOISTURE HAS BEEN TAKING PLACE OVER THE LAST 24 HOURS.

SEVERE THUNDERSTORMS ARE LIKELY TO BE ONGOING AT THE BEGINNING OF THE PERIOD WHICH WILL CONTINUE TO SWEEP RAPIDLY EASTWARD INTO EASTERN OKLAHOMA DURING THE MORNING AND EARLY AFTERNOON HOURS.  SUFFICIENTLY STEEP LAPSE RATES AND IMPRESSIVE SHEAR PROFILES WILL SUPPORT MARGINALLY SEVERE HAIL AND A GOOD CHANCE OF WIND DAMAGE.  ISOLATED EMBEDDED CIRCULATIONS MAY BE ABLE TO PRODUCE WEAK TORNADO DAMAGE IN SOME CASES.

WHILE CHANCES ARE LOW – THERE IS SOME POTENTIAL FOR REDEVELOPMENT OF STORMS BEHIND THE INITIAL LINE – OVER EAST CENTRAL AND SOUTHEAST OKLAHOMA DURING THE LATE AFTERNOON.

ON THIS DATE IN 1956… A LARGE AND POWERFUL TORNADO – ONE OF MANY TO STRIKE THE NORTHERN PORTION OF OKLAHOMA THAT DAY – HIT DRUMRIGHT.  FOUR PEOPLE WERE KILLED AND 12 WERE INJURED.  A TWO BLOCK WIDE AND ONE MILE LONG STRETCH FROM DOWNTOWN TO NORTHEAST RESIDENTIAL HOMES WAS DESTROYED.  ONE YEAR LATER… FIVE PEOPLE WERE KILLED BY TORNADOES IN SOUTHERN OKLAHOMA WHICH HIT NEAR DURANT… DAVIS AND LITTLE CITY.040210z

SEVERECAST DAY 32a – 9:03 p.m., THURSDAY, APRIL 1

…SEVERE THUNDERSTORMS A GOOD POSSIBILITY ACROSS OKLAHOMA BEFORE SUNRISE…

EVENING UPPER AIR SOUNDINGS SHOW THAT MOISTURE IS STILL FAIRLY LIMITED IN THE SOUTHERN PLAINS – DESPITE VERY STRONG SOUTH WINDS THAT HAVE BEEN OCCURRING OVER THE PAST COUPLE OF DAYS.  STILL… INCREASING LIFT ASSOCIATED WITH APPROACH OF STRONG UPPER STORM AND THE LOW LEVEL JET WILL BE ABLE TO TAKE ADVANTAGE OF WHAT MOISTURE IS AVAILABLE FOR THE DEVELOPMENT OF THUNDERSTORMS SOON NEAR THE WESTERN BORDER OF THE STATE.

LATEST SHORT RANGE AND HIGH-RESOLUTION MODEL DATA SUPPORTS THE SOLUTION OF STORMS FORMING… BECOMING QUITE STRONG AND THEN RACING NORTHEASTWARD TOWARD THE CENTRAL AND NORTH CENTRAL PORTION OF THE STATE BY MORNING.

VERY STEEP LOW AND MID LEVEL LAPSE RATES ARE STARTING TO SPREAD INTO WESTERN OKLAHOMA.  THAT COMBINED WITH IMPRESSIVE SHEAR PROFILES WILL SUPPORT SOME OF THE STORMS BEING ABLE TO BECOME SEVERE… WITH THE MAIN THREAT BEING MARGINALLY SEVERE HAIL AND TO A SLIGHTLY HIGHER DEGREE – WIND DAMAGE.

GIVEN THE DEGREE OF SHEAR IN BOTH THE LOW LEVELS AND DEEP LAYER… BOWING LINE SEGMENTS MAY BE ABLE TO SUPPORT VORTICES WHICH COULD TRANSLATE TO TORNADO EVENTS.

THE CHANGE IN FORECAST THINKING THIS EVENING TAKES INTO CONSIDERATION A HIGHER CHANCE OF WIND DAMAGE/ISOLATED TORNADO EVENTS… AND ALSO SHIFTS THE THREAT AREA SLIGHTLY NORTHEASTWARD TO ACCOUNT FOR THE THREAT OF SEVERE WEATHER LASTING LONGER.

IT SHOULD BE NOTED THAT NOCTURNAL TORNADO EVENTS IN OKLAHOMA ARE QUITE RARE… EVEN DURING THE PEAK OF THE SEVERE WEATHER SEASON AND WITH ADEQUATE MOISTURE/INSTABILITY.  THE TORNADO THREAT OVERNIGHT SHOULD BE CONSIDERED EXTREMELY “LOW-END”.

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SEVERECAST DAY 32 – MIDNIGHT, THURSDAY, APRIL 1

…SEVERE THREAT RETURNS TO THE STATE TO OPEN THE MONTH OF APRIL…

LATEST NAM SUGGESTS THAT A VERY STRONG UPPER STORM WILL BE MOVING THROUGH SOUTHERN CALIFORNIA THURSDAY MORNING.  THIS MODEL DATA ALSO SUPPORTS THE IDEA OF A PIECE OF THIS SYSTEM MOVING RAPIDLY NORTH NORTHEASTWARD TOWARD THE NORTHERN PLAINS – WHILE A STRONGER PORTION OF THE STORM CONTINUES TO DIG TOWARD THE TEXAS BIG BEND BY FRIDAY MORNING.

EVENING SOUNDINGS SHOW THAT ANY MOISTURE RETURN HAS BEEN SLOW TO OCCUR THUS FAR.  THE ONLY NOTICEABLE DEPTH IS NOTED ALONG THE TEXAS COAST.

AS THE LONG WAVE TROUGH APPROACHES THE PLAINS… AN ALREADY STRONG LOW LEVEL JET WILL STRENGTHEN AND A RAPID RETURN OF MODEST MOISTURE WILL OCCUR BY EVENING.  RETURN SHOULD BE SUFFICIENT TO ALLOW THE ATMOSPHERE TO BECOME MODERATELY UNSTABLE BY AFTERNOON ALONG AND EAST OF A DRY LINE WHICH WILL EXTEND FROM CENTRAL NEBRASKA SOUTHWARD TO NEAR THE OKLAHOMA/TEXAS PANHANDLE BORDER.

FORECAST SOUNDINGS SHOW THAT THE ATMOSPHERE WILL REMAIN CAPPED DURING THE DAYLIGHT HOURS.  HOWEVER… INCREASING LIFTING ASSOCIATED WITH THE APPROACH OF THE UPPER LEVEL TROUGH AND INCREASING LOW LEVEL JET SHOULD BE SUFFICIENT FOR THUNDERSTORM DEVELOPMENT BETWEEN SUNSET AND MIDNIGHT OVER PORTIONS OF WESTERN OKLAHOMA.  THESE STORMS – WHILE MOSTLY ELEVATED – WILL HAVE ENOUGH MOISTURE/INSTABILITY AND SHEAR AVAILABLE TO SUPPORT VIGOROUS – SOMETIMES ROTATING UPDRAFTS.  THIS WILL HELP LEAD TO LARGE HAIL PRODUCTION AND DAMAGING WINDS WITH THE STRONGER STORMS.  THE SOMEWHAT LIMITED MOISTURE AND ELEVATED NATURE OF THE STORMS SHOULD LIMIT TORNADO POTENTIAL.

ON THIS DATE IN 2006… SEVERE THUNDERSTORMS PRODUCED LARGE HAIL AND WIND DAMAGE ACROSS A LARGE PORTION OF OKLAHOMA.  THE ONLY TORNADO REPORTED FORMED NEAR THE TULSA INTERNATIONAL AIRPORT WHICH CAUSED EXTENSIVE DAMAGE AT A HOTEL… INJURING SEVEN PEOPLE.  75 CARS WERE ALSO DAMAGED.

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March Severe Weather Summary

Severe weather in March in Oklahoma was limited.  If it were not for a high profile tornado event on the 8th… most people wouldn’t even know that there was severe weather in the state.

A cluster of severe storms formed in western Oklahoma on the afternoon of the 8th.  One of the storms organized into a long-lived supercell which produced a tornado that lasted for 40 minutes.  The tornado moved into the southeast side of Hammon and produced EF2 damage.  Most of the life of this tornado was caught by local media which carried the event live.  About 15 minutes after the tornado dissipated… another brief tornado occurred with the storm about 7 miles north of Butler.  (Information is based from data compiled by Doug Speheger – National Weather Service Norman, OK)  Again… had it not been for this single – highly visible and long-lived tornado – this severe weather day would not be considered significant.

The second day of severe reports brought marginally severe hail to the Ponca City area on the 10th.

The third and final day with severe weather produced an isolated occurrence of wind damage just southeast of Pocola in Le Flore County.

Overall… the start of the severe weather season in Oklahoma was a quiet one (except for the folks in Hammon).  Three days with severe weather and one day with tornadoes for the month of March.  I am going to stick to my forecast of this being a season with above normal tornado days and above normal tornadoes… despite the slow start.

SEVERECAST DAY 31 – MIDNIGHT, WEDNESDAY, MARCH 31

…NO THUNDERSTORMS EXPECTED WEDNESDAY…

A VERY STRONG SEGMENT OF THE MID/UPPER LEVEL JET WILL DIVE SOUTHEASTWARD ALONG THE WEST COAST ON WEDNESDAY… HELPING TO CARVE OUT A DEEP LONG WAVE TROUGH THROUGH THE WESTERN U.S.  THE SOUTHERN PLAINS WILL BENEFIT WITH LOWERING SURFACE PRESSURES AND STRONG SOUTH WINDS WHICH WILL HELP PUSH AFTERNOON HIGHS ABOVE SEASONAL NORMAL’S. MOISTURE WILL STILL BE LIMITED THIS PERIOD AND THUNDERSTORMS ARE NOT EXPECTED.

ON THIS DATE IN 1914… A MID-AFTERNOON TORNADO FORMED IN SOUTHEAST ENID AND MOVED TO JUST SOUTH OF BRECKENRIDGE.  FOUR HOMES WERE DESTROYED AND 20 WERE DAMAGED.

SEVERECAST DAY 30 – MIDNIGHT, TUESDAY, MARCH 30

…NO THUNDERSTORMS EXPECTED TUESDAY…

NORTHEAST TO SOUTHWEST RIDGE OF HIGH PRESSURE WILL SHIFT EAST TODAY AS LARGE TROUGH BEGINS TO BECOME ESTABLISHED OVER THE WESTERN U.S.  INCREASING SOUTHWEST FLOW ALOFT WILL SPREAD OVER THE STATE BY DAYBREAK WEDNESDAY.

IN RESPONSE… SURFACE PRESSURES WILL BEGIN FALLING AND STRONG SOUTH WINDS WILL BE FELT ACROSS ALL OF THE STATE TODAY.  HOWEVER, MOISTURE WILL BE SLOW TO RETURN AND INCREASED STORM CHANCES STILL LOOK TO BE SEVERAL DAYS AWAY.

INDICATIONS ARE THAT A SEVERE THREAT MAY FORM IN OKLAHOMA ON FRIDAY.

ON THIS DATE IN 1949… THREE WERE KILLED, 23 INJURED AND $500,000 WORTH OF PROPERTY WAS DAMAGED OR DESTROYED AS A COUPLE OF TORNADOES TRACKED ACROSS NORTHWEST OKLAHOMA JUST AFTER MIDNIGHT.  THE WORST DAMAGE WAS NEAR HOMESTEAD AND ISABELLA, NORTHEAST OF CANTON.

SEVERECAST DAY 29 – MIDNIGHT, MONDAY, MARCH 29

..NO THUNDERSTORMS EXPECTED TODAY…

NORTHEAST TO SOUTHWEST ORIENTED UPPER RIDGE OVER THE PLAINS WILL BEGIN TO FLATTEN SOME DURING THE PERIOD AS POWERFUL JET STREAM WINDS BEGIN TO SPREAD INTO THE WESTERN U.S.  WHILE SURFACE WINDS WILL RETURN TO THE SOUTH TODAY… THE ATMOSPHERE WILL REMAIN DRY.

ON THIS DATE IN 1945… IT’S HARD TO FIND INFORMATION ON SEVERE WEATHER DURING WORLD WAR II.  TUCKED BETWEEN HEADLINES SUCH AS “1ST GAINS 55 MILES IN ONE-DAY SWEEP AROUND NAZI FORCE” AND “SOVIET FORCES REACH AUSTRIA” – THE DAILY OKLAHOMAN REPORTED THAT THE TOWNS OF POLLARD, REDLAND AND SHULTS IN EXTREME SOUTHEAST OKLAHOMA WERE HEAVILY DAMAGED BY A TORNADO.

SEVERECAST DAY 28 – MIDNIGHT, SUNDAY, MARCH 28

…NO THUNDERSTORMS EXPECTED SUNDAY IN OKLAHOMA…

UPPER TROUGH THAT EXTENDS FROM THE OHIO VALLEY INTO TEXAS WILL SWING SOUTHEASTWARD THROUGH THE DAY… WHILE A LARGE UPPER RIDGE BEGINS TO BUILD FROM THE SOUTHWEST U.S. INTO THE NORTHERN PLAINS.

THIS WILL BE THE FIRST DAY OF AN EXTENDED PERIOD OF WARMER AND DRIER WEATHER WITH THE NEXT SIGNIFICANT CHANCE OF STORMS NOT LIKELY UNTIL AFTER THE 1ST OF APRIL.

ON THIS DATE IN 1924… NUMEROUS SEVERE THUNDERSTORMS INFLICTED DAMAGE ACROSS THE SOUTHERN AND EASTERN PORTIONS OF OKLAHOMA.  SHAWNEE WAS HIT BY A TORNADO THAT WAS REPORTED TO BE TWO BLOCKS WIDE.  200 HOMES WERE DESTROYED AND AT LEAST EIGHT PEOPLE WERE KILLED.

Okarche, Oklahoma