SEVERECAST DAY 65 – 7 a.m., TUESDAY, MAY 4

…NO SEVERE THUNDERSTORMS EXPECTED… 

MODERATELY STRONG MID LEVEL FLOW WILL EXTEND FROM WEST TO EAST ACROSS MOST OF THE COUNTRY TODAY.  AT THE SURFACE… A COLD FRONT WILL PUSH THROUGH THE PANHANDLE AROUND MIDNIGHT – AND THROUGH CENTRAL OKLAHOMA BY DAYBREAK ON WEDNESDAY. 

THE ATMOSPHERE WILL REMAIN SEASONABLY DRY AND STABLE AND NO THUNDERSTORMS ARE EXPECTED. 

WHILE THERE WILL BE A COUPLE OF DRY FRONTAL PASSAGES DURING THE NEXT FEW DAYS… MOISTURE RETURN IS NOT EXPECTED TO FULLY KICK IN UNTIL LATE IN THE UPCOMING WEEKEND.  BY SUNDAY… THUNDERSTORM CHANCES WILL BE INCREASING WITH THE THREAT OF STORMS EXTENDING INTO THE FOLLOWING WEEK. 

ON THIS DATE IN 1960… SEVERE THUNDERSTORMS PRODUCED SEVERAL TORNADOES IN CENTRAL AND SOUTHERN OKLAHOMA.  TWO OF THE STRONGEST TORNADOES OCCURRED IN SEMINOLE AND CHOCTAW COUNTIES.  EVERYONE HAD TAKEN SHELTER NEAR KONAWA WHEN A TORNADO “COMPLETELY SWEPT AWAY” SOME FARM HOMES.  A NORTHWARD MOVING TORNADO DESTROYED OR DAMAGED UP TO 100 HOMES, OR ABOUT A THIRD OF THE TOWN OF SOPER.

SEVERECAST DAY 64 – 7 a.m., MONDAY, MAY 3

…A FEW STRONG THUNDERSTORMS POSSIBLE OVER SOUTHERN AND EASTERN OKLAHOMA THIS AFTERNOON AND EVENING… 

A SMALL AND FAIRLY STRONG MID LEVEL CIRCULATION HAS EVOLVED OUT OF THE BASE OF THE PLAINS TROUGH AND IS MOVING THROUGH WESTERN TEXAS.  THE MORNING NAM TAKES THIS FEATURE EAST INTO THE SOUTHERN MISSISSIPPI VALLEY BY TUESDAY MORNING.  ASSOCIATED LIFTING WILL BE SKIRTING SOUTH CENTRAL AND SOUTHEAST OKLAHOMA AT PEAK HEATING THIS AFTERNOON.  

THE COMBINATION OF THIS LIFT AND SURFACE HEATING WILL BE SUFFICIENT TO PRODUCE SCATTERED THUNDERSTORMS OVER MAINLY SOUTHERN AND EASTERN OKLAHOMA.  FAIRLY STEEP LAPSE RATES MAY ALLOW SOME OF THE STORMS TO BECOME QUITE STRONG WITH THE POTENTIAL FOR GUSTY WINDS AND SMALL HAIL.  HOWEVER… THE INSTABILITY DOES NOT APPEAR THAT IT WILL BE SUFFICIENT FOR ORGANIZED SEVERE STORMS.  

ON THIS DATE IN 1999… A DATE WHICH WILL ALWAYS BE REMEMBERED IN OKLAHOMA TORNADO LORE.  A MAJOR TORNADO OUTBREAK AFFECTED MAINLY CENTRAL OKLAHOMA AND EXTENDED INTO PORTIONS OF NORTH CENTRAL AND NORTHEAST OKLAHOMA.  THE OUTBREAK WILL BE REMEMBERED FOR PRODUCING AROUND 60 TORNADOES DURING THE LATE AFTERNOON AND EVENING… KILLING 40 PEOPLE AND GENERATING A VIOLENT, F5 TORNADO WHICH STRUCK THE OKLAHOMA CITY METRO AREA.  HOWEVER, THIS POST IS DEDICATED TO ONE OF THE “FORGOTTEN STORMS” OF THE DAY.

SEVERECAST DAY 63 – 7 a.m., SUNDAY, MAY 2

…NO SEVERE THUNDERSTORMS EXPECTED… 

A LARGE – UPPER LEVEL – TROUGH OF LOW PRESSURE WILL REMAIN POSITIONED OVER THE CENTRAL U.S. THROUGH THE PERIOD.  BY MONDAY MORNING… IT APPEARS THAT A CLOSED LOW WILL TRY TO EVOLVE AT THE SOUTHERN END OF THIS TROUGH… OVER NEW MEXICO.  THE RESULT WILL BE CONTINUED SOUTHWEST FLOW ALOFT ACROSS THE STATE.  

THE LOW LEVEL BOUNDARY WHICH SEPARATES COOLER AND DRIER AIR FROM VERY MOIST AIR WILL REMAIN JUST EAST OF THE STATE.  A WEAK FRONT WILL BECOME ORGANIZED IN KANSAS THIS AFTERNOON AND SLIP SOUTHWARD TOWARD CENTRAL OKLAHOMA BY THE END OF THE PERIOD.  

THE ATMOSPHERE IS EXPECTED TO REMAIN TOO DRY AND STABLE TO SUPPORT SEVERE STORMS. 

ON THIS DATE IN 1979… LESS THAN A MONTH AFTER KILLER TORNADOES STRUCK WICHITA FALLS, TEXAS AND LAWTON… STRONG TORNADOES HIT PORTIONS OF CENTRAL AND NORTHERN OKLAHOMA.  THE LARGEST TORNADO… ABOUT 24 MILES LONG AND RATED F4… MOVED FROM 3 MILES NORTHEAST OF CLEO SPRINGS – EAST SOUTHEASTWARD – TO JUST NORTH OF RINGWOOD BEFORE STRIKING LAHOMA.  ONE PERSON WAS KILLED AND 25 INJURED.  OTHER STRONG TORNADOES FORMED NEAR ORIENTA AND FAIRVIEW… MARSHALL… MULHALL… AND PERKINS.

SEVERECAST DAY 62 – 7 a.m., SATURDAY, MAY 1

…NO SEVERE THUNDERSTORMS EXPECTED IN OKLAHOMA TODAY… 

A LARGE TROUGH OF LOW PRESSURE IN THE UPPER LEVELS WILL EXTEND FROM THE NORTHERN PLAINS TO THE SOUTHERN ROCKIES AND MAKE ONLY SLIGHT EASTWARD ADVANCEMENT THROUGH THE PERIOD.  STRONG JET STREAM LEVEL WINDS WILL BE BLOWING FROM WESTERN TEXAS TO THE UPPER MIDWEST.  

AT THE SURFACE… A COUPLE OF WEAK SURFACE BOUNDARIES OVER EASTERN OKLAHOMA WILL SHIFT EASTWARD INTO ARKANSAS.  DRIER AIR WHICH HAS ALREADY WORKED ITS WAY INTO CENTRAL AND WESTERN OKLAHOMA WILL PUSH EAST.  

WHILE SURFACE BASED INSTABILITY WILL LESSEN WITH TIME AS THE MAIN FRONT SHIFTS EAST… SOME ELEVATED INSTABILITY IS EXPECTED TO DEVELOP OVER MAINLY THE SOUTHEAST CORNER OF THE STATE.  THIS WILL HELP TO ENHANCE THUNDERSTORMS SOME IN THAT AREA WITH MARGINALLY SEVERE HAIL POSSIBLE FOR A TIME THIS AFTERNOON AND EVENING.  AN ORGANIZED SEVERE THREAT IS NOT EXPECTED TO DEVELOP. 

ON THIS DATE IN 1936… THERE WERE NOT MANY SIGNIFICANT SEVERE WEATHER EVENTS IN THE STATE… HOWEVER, WHAT MAY HAVE BEEN A VIOLENT TORNADO STRUCK NEAR ALBERT IN CADDO COUNTY.  THREE PEOPLE WERE KILLED AND 13 INJURED – ALL IN TWO FAMILIES – AS THEIR FARMS WERE SWEPT AWAY.  THE TORNADO MOVED FROM SOUTH TO NORTH AND WAS NEARLY 400 YARDS WIDE.

SEVERECAST DAY 60 – 7 a.m., THURSDAY, APRIL 29

…NO SEVERE THUNDERSTORMS EXPECTED IN OKLAHOMA…

A DEEP TROUGH OF LOW PRESSURE IS LOCATED OVER THE WESTERN U.S… WITH SEVERAL VORT MAXIMA FORECAST TO EJECT NORTHEASTWARD ACROSS THE CENTRAL AND NORTHERN PLAINS.

DEEP SURFACE LOW PRESSURE IS FOUND ACROSS MOST ALL OF THE PLAINS.  LATEST NAM SUGGESTS THAT 983 MB SURFACE LOW WILL TAKE SHAPE IN WESTERN KANSAS.  STRONG SOUTH WINDS WILL CONTINUE TO BLOW ACROSS OKLAHOMA.

BY AFTERNOON… A DRY LINE WILL START TO ADVANCE EASTWARD THROUGH THE PANHANDLE AND INTO WESTERN OKLAHOMA.  STRONG SURFACE HEATING AND A GRADUAL INCREASE IN MOISTURE WILL RESULT IN THE ATMOSPHERE BECOMING QUITE UNSTABLE.  DESPITE THIS… FORCING FROM ANY MECHANISM SHOULD BE MINIMAL.  COMBINED WITH A STRONG CAPPING INVERSION AND THE CHANCES OF STORM INITIATION LOOK VERY LOW.  STILL – THERE IS A VERY SLIGHT CHANCE AT A STORM BEING ABLE TO FORM ALONG THE DRY LINE.  IF THIS BECOMES MORE LIKELY… A RISK WILL NEED TO BE INCLUDED LATER TODAY.  STORMS THAT DO MANAGE TO FORM WILL HAVE THE POTENTIAL TO BE SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS.  TORNADO THREAT WILL LIKELY BE MINIMIZED BY FAIRLY HIGH TEMP/DEW POINT SPREADS – HIGHER CLOUD BASES.

ON THIS DATE IN 1954… A LONG TRACK TORNADO FORMED IN THE ANTELOPE HILLS IN NORTHERN ROGER MILLS COUNTY.  IT TRACKED FOR 33 MILES ACROSS PORTIONS OF ROGER MILLS, ELLIS AND DEWEY COUNTIES… STAYING IN RURAL AREAS.  FIVE FARMS WERE HIT SOUTH OF VICI, DESTROYING BARNS AND OUTBUILDINGS.  PAVEMENT WAS RIPPED OFF THE ROAD 17 MILES SOUTH OF ARNETT.  LATER, A SLOW MOVING TORNADO WAS REPORTED TO HAVE TRACKED ONLY FOUR MILES IN 15 MINUTES SOUTHEAST OF LOYAL IN KINGFISHER COUNTY.  AFFECTING FOUR FARMS… TWO PEOPLE WERE INJURED.

Active weather pattern produces at least 72 tornadoes over six days…

The weather pattern became an active one from April 20 to April 25 and produced at least 72 tornadoes from Colorado to North Carolina.

On the 20th… two tornadoes occurred in the Texas panhandle.  One of which looked rather large but got rated EF0 because it didn’t hit anything.

On the 21st… a weak tornado occurred in Colorado.

On the 22nd… many tornadoes occurred in Colorado, Kansas, Texas and Oklahoma.  The lone tornado in Oklahoma was a weak event in Beaver County.  Most of the tornadoes stayed in rural areas and none were rated greater than EF1.  It’s possible that as many as 27 tornadoes occurred.

On the 23rd… there may have been as many as 11 tornadoes scattered across Colorado, Missouri, Arkansas, Louisiana, Mississippi and Texas.

On the 24th… a large outbreak of more significant tornadoes occurred.  The strongest tornadoes were in Mississippi and Alabama where two EF4’s were surveyed.  The long track supercell that produced one of the violent tornadoes (hitting Yazoo City and responsible for 10 deaths) was alive for more than seven hours.  Here is a radar composite of the storm:  http://www.okweatherwatch.com/2010/00.jpg

I’ve also listed a summary of the 29 tornadoes which occurred on the 24th here:  http://www.okweatherwatch.com/2010/042410sum.htm

On the 25th… two tornadoes occurred in South Carolina and North Carolina.  The South Carolina storm was rated EF2.

One of two tornadoes I observed southeast of Groom, TX on April 22nd.

One of two tornadoes I observed southeast of Groom, TX on April 22nd.

SEVERECAST DAY 59 – 7 a.m., WEDNESDAY, APRIL 28

…DRY, WINDY DAY EXPECTED IN OKLAHOMA…

AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL SHIFT EAST OUT OF THE PLAINS AND INTO THE MISSISSIPPI VALLEY DURING THE PERIOD.  WINDS WILL INCREASE IN STRENGTH OUT OF THE SOUTHWEST AS A LARGE AND STRONG TROUGH OF LOW PRESSURE CARVES ITS WAY INTO THE WESTERN U.S.

A VERY DEEP AREA OF SURFACE LOW PRESSURE WILL ORGANIZE NEAR THE KANSAS/COLORADO BORDER IN RESPONSE TO THE APPROACHING UPPER STORM.  WINDS WILL INCREASE OUT OF THE SOUTH AND OVER THE NORTHWEST HALF OF THE STATE WILL BE QUITE GUSTY.  GUSTS OVER 50 MPH WILL BE POSSIBLE.

DESPITE THE EVOLUTION OF A DRY LINE WHICH WILL MOVE THROUGH THE PANHANDLE… THE ATMOSPHERE IS EXPECTED TO REMAIN WELL CAPPED AND THUNDERSTORMS ARE NOT EXPECTED.

AS THE SYSTEM TO OUR WEST APPROACHES… SEVERE THUNDERSTORMS ARE A SLIGHT POSSIBILITY AFTER SUNSET IN WESTERN OKLAHOMA ON THURSDAY.  FRIDAY… THERE WILL BE A SLIGHT RISK OF SEVERE WEATHER IN THE EASTERN PART OF THE STATE.

ON THIS DATE IN 1960… TORNADOES BEGAN FORMING JUST SOUTHWEST OF OKLAHOMA CITY DURING THE EARLY EVENING HOURS.  ONE STORM PRODUCED A TORNADO NEARLY 10 MILES LONG WHICH MOVED THROUGH THE SOUTH SIDE OF OKLAHOMA CITY.  DAMAGE WAS WORST IN THE AREA AROUND SW 59 AND PENNSYLVANIA.  1500 HOMES WERE DAMAGED OR DESTROYED.  THE STORM FIRST AFFECTED THE “WEATHER BUREAU” AT WILL ROGERS WORLD AIRPORT KNOCKING GLASS OUT OF THE TOWER.  THE WEATHER OFFICE RECORDED 86 MPH WINDS.  NOBODY WAS KILLED IN THE EVENT… HOWEVER, 51 PEOPLE WERE INJURED.  IT WAS SAID THAT THERE WERE A LOT OF “CLOSE CALLS”.

SEVERECAST DAY 58 – 7 a.m., TUESDAY, APRIL 27

…NO SEVERE THUNDERSTORMS EXPECTED IN OKLAHOMA…

A RIDGE WILL BUILD OVER THE PLAINS TODAY AS A DEEP TROUGH SHIFTS TOWARD THE EASTERN COAST AND A STRONG UPPER JET SEGMENT SURGES ONSHORE WEST.

AT THE SURFACE… HIGH PRESSURE WILL MOVE SOUTHEAST OF OKLAHOMA… RETURNING WINDS TO THE SOUTH OVER MOST OF THE STATE BY DAYBREAK WEDNESDAY.

THE ATMOSPHERE WILL REMAIN DRY AND STABLE WITH NO THUNDERSTORMS EXPECTED.

ON THIS DATE IN 1942… A SOUTHEASTWARD MOVING STORM DROVE A STRONG TORNADO THROUGH THE CITY OF PRYOR IN NORTHEAST OKLAHOMA.  MANY VICTIMS IN THE BUSINESS DISTRICT WERE CAUGHT IN THEIR VEHICLES.  INITIAL REPORTS STATED THE FATALITIES WERE AS HIGH AS 100… HOWEVER THE FINAL TOLL WAS 52.  THIS STILL MAKES THIS TORNADO THE 4TH MOST DEADLY IN OKLAHOMA HISTORY.  ABOUT 350 PEOPLE WERE INJURED.

SEVERECAST DAY 57 – 7 a.m., MONDAY, APRIL 26

…NO SEVERE THUNDERSTORMS EXPECTED ON MONDAY IN OKLAHOMA…

NORTHWEST FLOW ALOFT WILL REMAIN OVER THE STATE THROUGH THE PERIOD.  A SHORT WAVE TROUGH WILL MOVE FROM THE CENTRAL HIGH PLAINS… SOUTHEASTWARD INTO KANSAS AND OKLAHOMA BY DAYBREAK TUESDAY.

AT THE SURFACE… A WEAK COLD FRONT WILL QUICKLY ADVANCE SOUTHEASTWARD ACROSS THE STATE DURING THE MORNING HOURS TODAY.  THE ATMOSPHERE ACROSS OKLAHOMA WILL REMAIN DRY AND QUITE STABLE… PREVENTING THUNDERSTORM DEVELOPMENT.

ON THIS DATE IN 1991… A LARGE OUTBREAK OF SEVERE THUNDERSTORMS AND TORNADOES OCCURRED ACROSS THE PLAINS.  IN OKLAHOMA… THE WORST SEVERE WEATHER WAS CONFINED TO NORTH CENTRAL AND NORTHEAST SECTIONS OF THE STATE.  THE LARGEST AND LIKELY THE MOST INTENSE TORNADO OF THE DAY WAS A 66 MILE LONG – ONE MILE WIDE – F4 – THAT TRACKED FROM JUST EAST OF GARBER TO JUST NORTHWEST OF PAWHUSKA.  THE TORNADO MANAGED TO REMAIN IN RURAL AREAS DURING ITS LIFE AND DESTROYED ONLY A HANDFUL OF STRUCTURES.

SEVERECAST DAY 56 – 7 a.m., SUNDAY, APRIL 25

…NO SEVERE THUNDERSTORMS EXPECTED SUNDAY…

A STRONG UPPER LOW PRESSURE AREA WILL SHIFT EASTWARD OUT OF ILLINOIS INTO OHIO DURING THE PERIOD.  WEAK SHORT WAVE RIDGING WILL BECOME ESTABLISHED OVER THE CENTRAL AND SOUTHERN PLAINS AS A SMALL BUT FAIRLY STRONG SHORT WAVE TROUGH MOVES SOUTHEASTWARD TOWARD NORTHEAST COLORADO/WESTERN NEBRASKA BY MONDAY MORNING.

AT THE SURFACE….WINDS WILL REMAIN DRY AND OUT OF THE WEST DURING THE DAY BEFORE A COLD FRONT SLIPS INTO THE NORTHWEST PART OF THE STATE BY MONDAY MORNING.  THIS WILL BRING COOLER AIR INTO THE PANHANDLE AND NORTHWEST ON NORTH WINDS.  THE ATMOSPHERE WILL REMAIN STABLE ENOUGH TO PREVENT THUNDERSTORMS.

ON THIS DATE IN 1957… LATE EVENING THUNDERSTORMS PRODUCED SEVERAL TORNADOES OVER EASTERN OKLAHOMA.  SHORTLY AFTER 10 P.M… A TORNADO FORMED OVER HOLDENVILLE.  THE TORNADO HAS BEEN RATED F2 AND CAUSED MOST OF ITS DAMAGE NEAR MAIN AND BROADWAY IN THE MIDDLE OF THE CITY.  THE PATH LENGTH WAS ABOUT TWO MILES LONG.

Okarche, Oklahoma